BE1025598A1 - METHOD, DEVICE AND COMPUTER PROGRAM FOR OVERLAYING A GRAPHIC IMAGE - Google Patents

Abstract

A computer-implemented method (5000) for overlaying a graphic image in a computing device, the method comprising the steps of: a) providing a semi-transparent overlay window with an alpha transparency value α in the range of 1% to 99% and comprising a first bitmap; repeatedly performing the following steps: b) taking a screenshot, thereby obtaining a second bitmap; c) determining at least one feature of the second bitmap; e) adjusting the alpha transparency value of the overlay window and / or adjusting one or more pixel values of the first bitmap, based on the at least one determined characteristic. The overlay method may further comprise a vertical blade to define different areas that can be adjusted individually depending on the image content among the areas.

Description

METHOD, DEVICE AND COMPUTER PROGRAM FOR OVERLAYING A GRAPHIC IMAGE

Domain of the invention

The present invention relates generally to the field of graphic overlay in a computer system. More specifically, the present invention relates to a computer-implemented method for providing a graphic overlay in a computer device or in a display device. The present invention also relates to a computer device configured to perform such a method, and to a computer program product for performing such a method in a computer device or in a display device. The present invention also relates to a portable computing device and to a display device.

BACKGROUND OF THE INVENTION

FIG. 1 shows a schematic block diagram of a classical computer system 100 comprising a computer device 101 (e.g. a desktop computer), with a keyboard input connected to a keyboard 102, and a mouse input connected to a mouse device 103, and a video output connected to a display or monitor or screen 104. The computer device 101 comprises a central processing unit CPU on which runs a multi-tasking operating system O / S with a graphical user interface GUI, and one or more software applications such as e.g. a text viewer or a text editor. Input from the keyboard 102 and mouse device 103 is usually handled by device drivers (device drivers) that receive information from one or more input port (s). Such computer systems and application programs are known in the art.

In the specific example of FIG. 1, the computer device 101 generates a graphic image that is displayed on the display 104 as indicated by the rectangular area 109 (shown with rounded corners and slightly offset with respect to the display edges for illustrative purposes). The graphic image 109 of FIG. 1 includes image portions related to a desktop window (visible on the left side of the screen 104), and related to an application window showing a text document (visible on the right side of the screen 104).

About two or three decades ago, when the internet was still in its infancy, many people preferred to read (or study) textual information printed on paper rather than directly from a screen, which at the time was usually a cathode ray tube. (CRT, Cathode Ray Tube) screen. At that time, most information, for example technical information, data sheets, product catalogs, manuals, computer magazines, etc., was primarily distributed in printed form and less information was available in electronic form.

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In contrast, nowadays (in 2017) very large amounts of information are provided or made available in electronic form, and many readers prefer to read directly from a screen, instead of first printing the information on paper and then read the paper version. This change is probably due to the advent of LCD screens (stable image, high resolution), the growth and speed of the internet, the increasing amount of information that is available electronically, the growing awareness to save trees by reducing printing , the availability of electronic document management tools (eg scanning, editing, annotating, searching), the increasing size of storage devices (eg hard disk, memory stick), the ability and speed to search electronically, the trend towards a paperless office, and the arrival of portable devices (such as smartphones, tablets, etc).

Technology has evolved considerably in the last few decades. On the one hand, printing has become easier, and with the advent of laser printers and inkjet printers, printer speed and printer quality have been considerably increased (compared to a matrix printer, for example). On the other hand, display quality is also considerably increased, and high-resolution LCD panels (eg with 1920 x 1080 pixels or even 3840 x 2160 at 60 Hz frame rate) are ubiquitous. Computers have become faster, with multiple processor cores operating at high speed (eg at 2 GHz), with more RAM (eg at least 4 or at least 8 Gigabytes of RAM), allowing multiple applications to run simultaneously.

The same trend is visible for portable devices, in particular smartphones: high screen resolution (for example 1920 x 1080 pixels, or 2560 x 1440 pixels, or 3840 x 2160 or 4096 x 2160 pixels are very common), multiple processor cores working at high clock speed (eg 1.5 GHz or more), large memory size (eg 4 Gigabytes of RAM and 32 Gigabytes of flash), etc. But printing from these devices is also very simple, eg using a wireless connection (eg Wi-Fi) instead of cables.

So people still have a choice between reading on the screen versus printing and reading on paper. However, this technological advancement may make it harder for people to read information on a screen.

While a higher image resolution usually means a sharper image, it usually also means that the font size is smaller, and that more text can be displayed on the screen. Smaller letters and more information in itself do not always make it easier to actually read that information, and can rather increase the difficulty of reading information.

A first problem encountered when reading textual information on a screen is that many people find it difficult to stay focused when it is required to read large amounts of text carefully (eg study), especially when the text is not contains a lot of formatting (such as bold or underlined characters, titles, different colors, different ones)

BE2018 / 5041 fonts, blank lines, etc.). This is, for example, the case when reading or studying published patent documents.

This first problem is recognized in the prior art, and is addressed, for example, by a tool (tool) known as LineReader, which is commercially available on the internet at the time of writing this document. This tool provides a graphic overlay window 483 with a semi-transparent (partially transparent) line 310 following the mouse pointer 399, as schematically illustrated in FIG. 3. In FIG. 3, the line 310 is colored gray because patent documents still have to be deposited in black and white, but in reality the line 310 can be colored red or blue, for example, which is more striking and easier to distinguish than the original (native) mouse pointer or mouse cursor 399 typically provided by an operating system (such as, for example, Mac O / S from Apple Inc. with headquarters in Cupertino, or Windows from Microsoft Corporation, Redmond), especially on high-resolution screens. People can use this tool to underline textual information that they are reading on the screen. The line can increase a user's ability to stay focused and focused.

However, as far as known to the inventors, no tool is available on the market that makes it easier for a user to find, edit, or verify data in a table or worksheet, or to locate a particular cell. Although there are literally hundreds of millions of people who have been using spreadsheets and worksheets daily for at least two decades, no obvious solution has been found.

Another problem encountered when reading or studying documents on the screen, or in general, when spending many hours a day on a computer screen, is that many people experience eye fatigue, especially when reading large amounts of text on a computer screen. clear background (eg when reading black text on a white background). Unfortunately, many programs (eg PDF viewers, text editors, etc.) and many web pages provide a clear, white background, probably because these programs are designed to display the information in the way it will be printed (such as the acronym WYSIWYG, that stands for what you see is what you get and that what you see is what you get means). Screens that display images with relatively large portions of black text on a white background send relatively large amounts of light energy to the eyes, which is very uncomfortable for many people. This inconvenience usually increases as people spend more hours in front of a computer screen, as the screen size increases, as the distance to the screen decreases, or combinations thereof, and is usually worse in a poorly lit room.

This problem is also recognized in the prior art, and one of the tools available in the market to address this problem is known as F.Lux, which provides a screen-filling semi-transparent graphic overlay, schematically shown in FIG. 5. This

BE2018 / 5041 tool can also be used to dynamically change the so-called color temperature during the course of the day. Relevant to the present invention is that tools (tools) such as F.Lux can reduce the brightness of the graphic image generated by the computer device, and thereby reduce eye fatigue. However, the decoration is not ideal, among other things because the overlay does not take into account the actual brightness of underlying windows, and / or because a user can no longer take a screen shot (screenshot) without the yellowish color that strongly colors the original images distorts, and / or because the adornment does not make it possible to underline or highlight textual information.

U.S. Patent No. 6,333,753, issued December 21, 2005, discloses a technique for implementing an on-demand display widget through controlled blurring (fading) initiated by user contact with a touch sensitive input device. The document describes a semi-transparent Tool Glass, optionally using a graphic accelerator. Fading in and fading out can be achieved by dynamically changing an alpha transparency value. This document is incorporated herein by reference in its entirety, especially FIG. 8 thereof, together with the accompanying description.

U.S. Patent No. 5,798,752, issued August 25, 1998, discloses a technique in which a user can move a semi-transparent overlay window containing a so-called workpiece with the non-dominant hand, and move the mouse pointer with the dominant hand.

Many people read books on an eReader device, but it's hard to stay focused. Some people use their finger to underline the text they are reading, but when the device is set aside, the location is lost. There is a need for a more practical way to stay focused.

Summary of the invention

It is an object of the present invention to provide a computer-implemented method for overlaying a graphic image generated by a computer device with an overlay image.

It is an object of certain embodiments of the present invention to provide an overlay window that includes at least one semi-transparent visible object that covers only a minority portion of the underlying graphic image, and that is movable in accordance with movements of an input device connected is with the computer device.

It is an object of certain embodiments of the present invention to provide such a method that is extremely suitable for assisting a user in reading textual information on a screen.

It is an object of certain embodiments of the present invention to provide such a method which is extremely suitable for assisting a user in

BE2018 / 5041 extracting information from a table or spreadsheet, or when editing a table or spreadsheet.

It is an object of certain embodiments of the present invention to provide such a method wherein the overlay image further comprises at least a second semi-transparent object covering a majority portion of the underlying graphic image.

It is an object of certain embodiments of the present invention to provide such a method with at least a first and a second semi-transparent object, wherein the second semi-transparent object has a higher transparency than the first semi-transparent object.

It is an object of certain embodiments of the present invention to provide such a method wherein the transparency of the first movable object is sufficiently low, so that this object can be easily distinguished from the background, and wherein the transparency of the second object is sufficiently is high, so that the underlying textual or alphanumeric information retains good readability.

It is an object of certain embodiments of the present invention to provide such a method which further comprises at least a third semi-transparent object, which is also movable in accordance with movements of the input device.

It is an object of certain embodiments of the present invention to provide such a method in which a substantially monochrome background color of an underlying image is transformed into a background with a texture pattern, preferably without significantly impairing the readability of the original textual information, and / or preferably with an aesthetically more attractive background.

It is also an object of the present invention to provide a computer device adapted to perform the said method.

It is also an object of the present invention to provide a computer program product for providing a graphic overlay, which computer program product, when executed on at least one processing unit of said computer device, performs said overlay method.

It is also an object of the present invention to provide a portable computing device that provides an overlay image.

It is also an object of the present invention to provide a display device that provides an overlay method.

It is also an object of embodiments of the present invention to provide a method of overlay that dynamically adjusts itself, depending on visible features of underlying windows.

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It is an object of specific embodiments of the present invention to provide an overlay method for darkening the screen that dynamically adjusts itself depending on the brightness of the underlying windows.

It is also an object of embodiments of the present invention to provide an overlay method that allows a screenshot of the underlying windows to be taken (as if the overlay were not there), but without deactivating the overlay application.

These and other objects are achieved by a method and a computer device and a computer program product and a computer system and a portable computing device and a display device according to embodiments of the present invention.

In a 1st aspect, the present invention provides a computer-implemented method for overlaying a graphic image in a computing device, the method comprising the steps of: a) providing an overlay window; b) providing at least one visible object in said overlay window, the at least one visible object comprising a bitmap with: a first plurality of pixels that are fully transparent pixels, and a second plurality of pixels that are opaque pixels or semi-transparent pixels to be; wherein the first plurality of pixels and the second plurality of pixels are alternately positioned (interleaved); c) configuring the overlay window in click-through mode.

The overlay window can be configured as an opaque window, which means that this window can contain non-transparent pixels or fully transparent pixels, but not semi-transparent pixels. (The same visual effect would be obtained with a semi-transparent window with an alpha transparency of 100%).

Alternatively, the overlay window can be configured as a semi-transparent window with an alpha transparency a in the range of 1% to 99% or from 2% to 98% or from 5% to 95%, meaning that this window is completely transparent pixels or semi-transparent can contain transparent pixels, but no opaque pixels.

The bitmap with the fully transparent pixels interspersed with opaque or semi-transparent pixels is referred to herein as a perforated bitmap (by analogy with a perforated plate where one can see through the openings).

By graphic image is meant the image formed by the underlying layers of associated applications. The graphic image can comprise or be composed of a layered stack of partial images, at least some of which are provided by an application window associated with a computer application, such as a text editor, a PDF document viewer, an internet browser, a spreadsheet, etc. image (so-called desktop image) can be generated by an operating system,

BE2018 / 5041 the optional other images of the stack can be generated by applications such as a text editor, PDF document viewer or editor, a web browser, a spreadsheet, a drawing program, etc.

Preferably, the overlay window extends substantially over the entire graphics area, for example (in a Windows environment) it can extend over the so-called work area (work area), which is the entire desktop area (minus the area occupied) by a so-called taskbar (taskbar).

The term fully transparent pixel is well known in the art. In practice, it is usually implemented by assigning a predefined pseudo color value to these pixels.

The bitmap may contain at least one row and / or at least one column containing at least one fully transparent pixel that is located between two opaque or between two semi-transparent pixels, preferably at least two rows and at least two columns.

The bitmap may contain at least one row and / or at least one column containing at least one opaque or semi-transparent pixel that is located between two fully transparent pixels, preferably at least two rows, more preferably each row.

The bitmap may contain at least one row and / or at least one column containing a plurality of odd and even-numbered sets of pixels, an odd-numbered set being composed of only one or at least one fully transparent pixel, and in which an even-numbered set is composed of only one or at least one opaque or semi-transparent pixel.

In one embodiment, the at least one visible object comprising the bitmap occupies a majority portion of the area of the graphic image to be overlayed, e.g. at least 75%, or at least 80% or at least 85% or at least 90% of the graphic image.

Expressed in simple terms, the semi-transparent object in this embodiment can, for example, form a film layer over the graphic image, which can be used to change the average color and / or the average light intensity of the graphic image.

The at least one visible object can be substantially stationary, in the sense that it does not move in accordance with movements of an input device.

In one embodiment, the method further comprises step d) wherein at least a second visible object is provided which is movable in accordance with movements of at least one pointing device, and which occupies only a minority part of the area of the graphic image to be overlaid.

In one embodiment, the at least one visible object comprising the bitmap is movable in accordance with movements of a pointing device and takes only one

BE2018 / 5041 minority portion of the area of the graphic image to be overlayed in, for example, at most 25%, often at most 20%, often at most 15%, often at most 10% or at most 5%.

Expressed in simple terms, the semi-transparent object in this embodiment can form a relatively small object, such as a small line, or a large line (which extends the full width of the screen), or a small cross, or a large cross (which extends over the full width and the full height of the screen), which moves in accordance with movements of a pointing device, for example a mouse device, a trackball, a touch pad, etc. Such an object is extremely suitable for marking or underline textual information in a text document, or alphanumeric information in a worksheet.

In one embodiment, the method further comprises the steps of: repeatedly performing the following step: f) obtaining position information (X, Y) related to a position of a mouse pointer or mouse cursor; or obtaining motion information (dx, dy) related to a motion of the at least one pointing device; and repeatedly performing the following step: g) adjusting a position of the at least one object that is movable and / or of the at least one second object that is movable, using said obtained position information or using said motion information.

For example, configuring the overlay window in click-through mode can be implemented (in an MS Windows environment) using one of the following function calls, or equivalent function calls:

SetWindowLong (Handle, GWL_EXSTYLE, WS_EX_TRANSPARENT or WS_EX_LAYERED);

SetWindowLong (Handle, GWL_EXSTYLE, GetWindowLong (Handle, GWL_EXSTYLE) or

WS_EX_TRANSPARENT);

As an example, obtaining position information may include querying the operating system and GUI which is the position of the native mouse cursor, for example (in an MS Windows environment) using the GetCursorPos () function.

As an example, obtaining motion information may include: configuring the O / S to send raw input messages, e.g., by registering the application with the O / S to receive raw input data, e.g., in the form of input messages known as WMJNPUT messages, for example by using the WinAPI function RegisterRawinputDevices (). It is noted that applications do not automatically receive raw input messages.

Step f) is preferably performed each time a new message arrives. Step g) may be based on a timer, for example with a period in the range of 1 ms to 100 ms, preferably in the range of 1 ms to 60 ms. Step g) therefore does not have to be performed with the same frequency as step f).

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In one embodiment, the at least one object that is movable and / or the at least one second object that is movable has an elongated shape.

For example a substantially rectangular shape, for example a rectangle with sharp edges, or a rectangle with truncated edges, or a rectangle with rounded edges, or a rectangle with rounded corners. Such a visible object can easily be generated or modified (size and / or color) on the fly (along the way), and is (by choosing a suitable height and width) ideal for underlining text without distracting a user.

In one embodiment, the at least one second movable object comprises a first movable element with an elongated, horizontally oriented shape, and a second movable element with an elongated, vertically oriented shape; and wherein step g) comprises adjusting a position of the first movable element and adjusting a position of the second movable element.

Or in simple terms: the first movable element and the second movable element form a cross. It is an advantage of overlaying with a cross that it can clearly indicate a particular cell in a spreadsheet or table.

In one embodiment the first movable element extends over a whole width of the overlay window, and the second movable element extends over a whole height of the overlay window.

It is an advantage of overlaying with a cross that extends over the entire width and height of the screen, that not only the desired cell is clearly indicated, but also the corresponding row header and column header ( column header) of the selected cell is clearly indicated.

In one embodiment, the first plurality of pixels and the second plurality of pixels of the bitmap are organized in a pseudo-random pattern.

In one embodiment, the first plurality of pixels and the second plurality of pixels of the bitmap are organized in a regular pattern.

In one embodiment, the first plurality of pixels and the second plurality of pixels of the bitmap are organized in a regular pattern according to one of the following options:

i) the regular pattern is a 2x2 pattern, and exactly one of four pixels is completely transparent;

ii) the regular pattern is a 2x2 pattern and exactly two of the four pixels are completely transparent, the two fully transparent pixels preferably being diagonally opposite each other;

iii) the regular pattern is a 2x2 pattern and exactly three of the four pixels are completely transparent.

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It is an advantage of using a 2x2 pattern that it is small relative to the entire screen size, and that the human eye tends to integrate the color and intensity of the four pixel values. Depending on how many pixels of the pattern are completely transparent (1 or 2 or 3 of the four), the overall intensity (or getting dark) can be roughly adjusted. If the second group of pixels is alpha-blended (English: alpha-blended value), then both the color of these pixels as well as the alpha blending value (English: alpha-blending value) can be used to fine tune the overall intensity (or getting dark) .

In one embodiment, the method further comprises the step of: repeatedly adjusting a position of the object containing the bitmap or of the bitmap such that pixels of the underlying graphic image are overlayed (covered) by a fully transparent pixel of the first plurality pixels at a first time point, and being overlayed by an opaque or semi-transparent pixel of the second plurality of pixels at a second and optionally third and fourth time points.

Preferably, the adjustment is made for every frame (e.g. at 60 Hz), or every two frames (e.g. at 30 Hz) or every 3 frames (e.g. at 20 Hz), or every 4 frames (e.g. at 15 Hz ). For example, the adjustment can be as simple as moving the second object or the entire overlay window by 1 pixel to the right or to the left or up or down. This can be seen as a kind of time multiplex.

In an alternative embodiment, a second bitmap is provided that is offset from the first bitmap of the object, and the method further comprises overlaying with the first bitmap at a first time, and overlaying with the second bitmap at a second and optional third and fourth time.

In one embodiment, step b) comprises: providing a bitmap wherein the second group of pixels are extracted or derived from a texture bitmap.

The texture bitmap can be a predefined bitmap or a selectable bitmap, or a modification thereof.

In the context of the present invention, a texture bitmap is preferably a bitmap that does not contain a graphic representation of easily recognizable letters or numbers, but rather contains a regular or irregular or pseudo-random pattern, an example of which is shown in FIG. 27; Another example is an image of a misty sky.

The texture bitmap can be much smaller than the bitmap of the at least one object in the overlay window, in which case it is repeated and / or tiled at least once and / or mirrored and / or rotated. Extracting pixel values from a smaller texture bitmap offers the advantage of saving memory. The use of non-constant values for the second group of pixels can give the user a paper-like appearance, which is more pleasant to read than a clear-white plastic-like view.

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In one embodiment, the overlay window is configured as a semi-transparent window with an alpha transparency (ot) in the range of 1% to 99% or from 2% to 98% or from 5% to 95%, and the method further comprises the step of of: adjusting pixel values of the second plurality of pixels extracted or derived from said texture bitmap, as a function of an alpha transparency value of the overlay window.

Preferably, the adjustment is made such that a contrast level of the texture remains substantially the same, despite variations in the alpha transparency value.

In one embodiment, the pixel values comprise three color components, for example, Red, Green and Blue, and each pixel value is adjusted using a linear expression of the respective color component itself, and optionally limiting the result of that linear expression to the range of 0 to 255.

As an example, the Red component can be adjusted according to the following formula, or an equivalent formula: R: = round ((R-Ravg) * Fcontrast + newR; limited to [0..255], where R is the original red value is of a pixel extracted from the texture bitmap, and Fcontrast is a predefined or selectable contrast factor (a floating point number) .This value preferably changes as a second-order function (e.g. as the square) of the transparency level T, where T = 100% -ct, newR is a desired or selected average value for the red components of the overlay image, which may be different from the average red value of the stored texture bitmap.

It is an advantage if each component value (eg Red) is calculated solely as a function of the original component value (in the example Red) and not of the other component values of that pixel (in the example: Blue and Green), because this calculates time saves, and can be implemented through a one-dimensional look-up table.

In one embodiment, the graphic image is generated as a layered composition of a desktop image and one or more images associated with said one or more applications; and the semi-transparent overlay window is created by an overlay application.

The at least one processor would typically further run an operating system (O / S) with a graphical user interface (GUI) that provides only a single mouse pointer, and one or more applications selected from the group consisting of: a web browser application, a spreadsheet application application, a PDF document viewer, a PDF document editor, a text viewer and a text editor.

In a 2nd aspect, the present invention also provides a computer-implemented method for overlaying a graphic image in a computing device, the method comprising the steps of: a) providing an overlay window; b) providing at least a first visible object in the overlay window, the first object having an elongated shape, being horizontally oriented, and a minority portion of the

BE2018 / 5041 takes overlay window; c) providing at least a second visible object in the overlay window, the second object having an elongated shape, being vertically oriented, and occupying a minority portion of the overlay window; d) configuring the overlay window in click-through mode; repeatedly performing the following step: f) obtaining position information (X, Y) related to a position of a mouse pointer or mouse cursor; or obtaining motion information (dx, dy) related to a motion of the at least one pointing device; and repeatedly performing the following step: g) adjusting a position of the first visible object and adjusting a position of the second visible object based on the obtained position information or using the motion information.

The first and second object together form a cross. Such an overlay is particularly useful when extracting data from a table, or when editing a spreadsheet.

In one embodiment, the first object extends over at least 80% of a width of the overlay window; and the second object extends at least 80% of a height of the overlay window.

Preferably, the overlay window extends substantially over the entire screen, or over the entire working area of the screen (in the context of a Windows environment, this means the entire area minus the area occupied by the taskbar).

Preferably, the first object has a rectangular shape with a width of at least 80% or at least 85% or at least 90% or at least 95% or equal to 100% of the width of the screen.

Preferably, the second object has a rectangular shape with a height of at least 80% or at least 85% or at least 90% or at least 95% or equal to 100% of the height of the screen.

The height of the horizontal object and the width of the vertical object are preferably equal.

In one embodiment, the method further comprises step b) of: configuring the overlay window as a semi-transparent overlay window with an alpha transparency in the range of 5% to 95% or of 10% to 90% or from 20% to 80%.

In an alternative embodiment, the method further comprises step b) of: configuring the overlay window as a non-semi-transparent window, also referred to herein as an opaque window.

In one embodiment, the first and second objects comprise a monochrome bitmap of pixels.

In one embodiment, the first and second objects comprise a bitmap with: a first plurality of pixels that are fully transparent pixels, and a second plurality of pixels that are opaque

BE2018 / 5041 or which are semi-transparent pixels to be alpha blended with pixels of windows that lie below the overlay window; wherein the first plurality of pixels and the second plurality of pixels are alternately positioned.

The first and second plurality of pixels can be arranged in a checkerboard pattern.

According to a 3rd aspect, the present invention also provides a computer-implemented method for overlaying a graphic image in a computing device, the method comprising the steps of: a) providing a semi-transparent overlay window; with an alpha transparency in the range of 5% to 95% or from 10% to 90% or from 20% to 80%; b) providing at least one bitmap in the overlay window, the bitmap at least 50% or at least 60% or at least 70% or at least 80% or at least 90% or approximately equal to 100% of the area of occupies the overlay window, the bitmap containing a texture bitmap; c) configuring the overlay window in click-through mode.

The use of a texture bitmap transforms a shiny or glossy, eg plastic-like, white background into a matte, eg paper-like background, whereby a nice aesthetic effect can be created that makes reading a document on a screen more pleasant.

In a 4th aspect, the present invention also provides a computer-implemented method for overlaying a graphic image in a computing device, the method comprising the steps of: a) providing an overlay window; b) providing a first visible object in the form of a vertical line; c) providing a second visible object in the form of a horizontal line segment that is located either on the left side or on the right side of the vertical line; wherein the second visible object is movable in accordance with movements of a pointing device; * repeatedly performing the following steps: d) obtaining position information from a mouse pointer or mouse cursor; e) testing whether the mouse cursor or pointer is on or above the vertical line, and if the result of the test is true, proceed to step f), otherwise proceed to step h); f) if the overlay window is not already configured in non-click-through mode, configuring the overlay window in non-click-through mode; g) testing whether a mouse button has been pressed, and if the result of this test is true, dragging the vertical line; and go to step d); h) if the overlay window is not already configured in click-through mode, configuring the overlay window in click-through mode; i) adjusting a position of the horizontal line segment based on the position information of the mouse pointer or mouse cursor.

This embodiment provides a line segment that freezes when the mouse cursor is on the right side of the vertical line or moves there, and that moves together with the mouse cursor when the mouse cursor is on the left side of the vertical line, or vice versa.

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Moreover, this embodiment makes it possible to drag the vertical line in a very intuitive way. This embodiment is particularly suitable for translators and proofreaders.

In one embodiment, step i) comprises: testing whether the mouse pointer or mouse cursor is on the same side of the vertical line as the horizontal line segment, and if the outcome of this test is true, adjusting a vertical position of the horizontal line segment in corresponding to a vertical position of the mouse pointer or mouse cursor, and if the result of this test is false, maintaining a position of the horizontal line.

In one embodiment, the horizontal line segment comprises a bitmap comprising: * a first plurality of pixels that are fully transparent pixels, and a second plurality of pixels that are opaque pixels or semi-transparent pixels; wherein the first plurality of pixels and the second plurality of pixels are interleaved (alternately positioned).

In one embodiment, the first plurality of pixels and the second plurality of pixels of the bitmap are organized in a pseudo-random pattern; or the first plurality of pixels and the second plurality of pixels of the bitmap are organized in a regular pattern.

In one embodiment, the first plurality of pixels and the second plurality of pixels of the bitmap are organized in a regular pattern according to one of the following options: i) the regular pattern is a 2x2 pattern, and exactly one of four pixels is completely transparent; ii) the regular pattern is a 2x2 pattern and exactly two of the four pixels are completely transparent, the two fully transparent pixels preferably being diagonally opposite each other; iii) the regular pattern is a 2x2 pattern and exactly three of the four pixels are completely transparent.

According to a 5th aspect, the present invention also provides a computer-implemented method for overlaying a graphic image in a computing device, the method comprising the steps of: a) providing a semi-transparent overlay window with an alpha transparency value in the range of 1% up to 99% or in the range of 5% to 95% or in the range of 10% to 90%, and comprising a first bitmap; repeatedly performing the following steps: b) taking a screenshot, thereby obtaining a second bitmap; d) determining at least one feature of the second bitmap; e) adjusting the alpha transparency value of the overlay window and / or adjusting one or more pixel values of the first bitmap based on the at least one particular characteristic.

It is an advantage of this method (where steps b) to e) are repeatedly performed) that the overlay can be dynamically adjusted based on actual characteristics of the underlying image (s), rather than being based solely on the time of day and the geographical location where the calculator is located (as seems to be the case for F.Lux). This is particularly useful for users who experience eye fatigue.

Thanks to this method, users suffering from eye fatigue do not have to manually overlay the parameters (for example alpha transparency and / or darkness of the overlay bitmap)

BE2018 / 5041, but this is handled automatically using the actual image content. For example, if the underlying images are clear images (eg with a white background such as in MS Word or MS Paint or MS Powerpoint), then more darkening can be used, while in the case that the underlying image (s) are less clear (eg certain web pages), less darkening can be used.

The loop can be repeated periodically, for example based on a timer that has a period in the range of 0.25 s to 10 s, or in the range of 0.5 s to 5 s, e.g. equal to about 1 second or about 2 seconds. The smaller this period, the higher the responsiveness of the calculator but the more computing power is required. The longer this period, the slower the system responds, but the less computing power is required. The skilled person who implements this function can find a suitable compromise. Optionally this period can be chosen by a user.

The first bitmap does not only consist of fully transparent pixels, so the first bitmap contains at least one semi-transparent pixel, typically about 50% semi-transparent pixels in case the first bitmap is perforated, or typically about 100 % from semi-transparent pixels in case the first bitmap is not perforated.

In one embodiment, the first bitmap is a monochrome bitmap, which can be a perforated monochrome bitmap or a non-perforated monochrome bitmap.

It is an advantage that such a bitmap can easily be generated from a single color value (e.g. with three color components R, G, B).

In a specific embodiment, the first bitmap contains only black pixels, or only grayscale pixels with (R, G, B) values equal to (χ, χ, χ), where x is a value less than 93, or less than 65, or less than 49, or less than 33, or less than 17. Such images are ideally suited for darkening the screen without changing the hue.

In other embodiments, the first bitmap contains a monochrome color bitmap with pixels having (R, G, B) values equal to (x, y, z), each of x, y, z being less than 93 or less than 65 , or less than 49, or less than 33, or less than 17. Such images are very well suited for darkening the screen, with a change in hue.

In another embodiment, the first bitmap contains a color gradient, for example a horizontal color gradient, or a vertical color gradient, or a diagonal color gradient.

The color gradient can be based on just two colors, for example a left and right color, an upper and lower color, a top left color and a bottom right color. It is an advantage that such a bitmap can easily be generated starting from only two color values (each with, for example, three color components R, G, B).

In one embodiment, the characteristic is determined using an under-sampled image, for example, by considering only 1 pixel from every 2x2 = 4 pixels, or by

BE2018 / 5041 by considering only 1 pixel from every 4x4 = 16 pixels, or by considering only 1 pixel from each 8x8 = 64 pixels, or by considering only 1 pixel from every 16x16 = 256 pixels. In this way the calculation time can be considerably reduced, while the effect is largely the same in most cases.

In one embodiment, step c) comprises: determining an average intensity and / or a maximum intensity and / or an intensity histogram of the pixels of the second bitmap; and includes step e): adjusting the alpha transparency level such that the average intensity or the maximum intensity or the intensity histogram meets a predetermined criterion.

The criterion may be, for example, that the average or maximum intensity should be less than a certain threshold value. The threshold value can be a predetermined value, or can be selectable by the user.

It is an advantage that in this way, the average or maximum intensity can be forced to be smaller than a certain threshold value.

It is an advantage of this method that only a single value (namely the transparency value) needs to be adjusted, which does not require a high CPU load. The target transparency value that meets the predetermined criterion can be calculated in one go, or can be approximated gradually over several iterations. The latter may cause less flicker.

In one embodiment, step c) comprises determining average color component values

Ravg, Gavg, Bavg and / or color component histograms of the pixels of the second bitmap; and includes step e): adjusting one or more pixel values of the first image (e.g., about 50% of the pixel values in the case that the bitmap is perforated, or about 100% of the pixel values in the case that the bitmap is not perforated) is) such that the average color component or color component histogram meets a predetermined criterion.

The target pixel values can be calculated in one go, or can be approximated gradually. The latter may cause less flicker. It is an advantage of adjusting the pixel values of the first bitmap that there is much more flexibility, because, for example, any of the color component values, or all component values, can be adjusted.

In one embodiment, the method further comprises step d) of determining a brightness value as an indication of a brightness in a room; and the adjustment of step e) further takes into account the brightness value.

In one embodiment, the brightness value can be determined using a light sensor, or using a webcam. It is an advantage of this embodiment that a poorly lit room can be overlayed differently than a bright room, even for the same underlying images.

BE2018 / 5041

In one embodiment, step a) further comprises: providing at least one vertical line or bar in the first bitmap for defining at least two regions including a first region and a second region; and step c) comprises determining at least a first feature of the first area and a second feature of the second area; and includes step e): adjusting one or more pixel values of the first region such that the first characteristic meets a first predetermined criterion, and adjusting one or more pixel values of the second region such that the second characteristic meets a second criterion.

It is an advantage of this embodiment that it allows the screen to be split into two areas, allowing a first application (e.g., a web browser) to be located in the first area (e.g., to the left of the vertical line or bar) and it is made possible for a second application (e.g. a word processor) to be in the second area (e.g. on the right side of the vertical line). The overlay application will automatically adjust a first feature of the first area (e.g., a first brightness and / or a first color), depending on the graphical information present on the left side of the vertical line, which is mainly based on the visited web page , and the overlay application will adjust a second feature of the second area, which may be the same feature or a different feature as the first feature, e.g., a second brightness and / or a second color, depending on the graphic information present on the right side of the vertical line, which in this example is mainly dependent on the background color of the word processor). In the case that a rather dark web page is visited, while the text document has a clear white background color, darker pixels can be assigned to the right side of the first bitmap than to the left of the first bitmap.

Or in other words: It is an advantage of this embodiment that the overlay bit map can be adjusted with various areas that can be made darker independently. This makes many more advanced screen adjustments possible, which is especially useful in a multi-tasking environment.

In one embodiment, one of the regions contains completely black pixels with (R, G, B) = (0,0,0), while the other bitmap is monochrome and contains grayscale pixels with (R, G, B) = (x, x, x), whereby the value of x is dynamically adjusted. The first and / or the second area can be perforated. Since the first and second regions are in the same overlay window, they have the same alpha mix value.

In one embodiment, the alpha mix value is predetermined (e.g., about 50% or about 60% or about 70% or about 80%), and the gray scale of the pixels of the second region is dynamically adjusted, or vice versa, or both the alpha mix value if the gray scale level x is both adjusted.

BE2018 / 5041

According to a 6th aspect, the present invention also provides a computer-implemented method for overlaying a graphic image in a computing device, comprising the steps of: a) providing a semi-transparent overlay window that has an alpha transparency value a in the range of 1 % to 99%, and a first bitmap; b) taking a screenshot, whereby a second bitmap is obtained; c) calculating a third bitmap to compensate for the effect of the graphic overlay based on the first bitmap and the second bitmap and the alpha transparency value.

Step b) can be initiated by clicking a button with a mouse pointer or by pressing a key on the keyboard.

It is an advantage of this method that it allows a realistic screenshot of the underlying windows to be taken, as if the overlay were not there, and without deactivating the overlay.

The inventors surprisingly realized that it is possible to recalculate the underlying image because they realized that the recorded image is in fact an alpha-mixed image of the stack of underlying images associated with the underlying applications and the bitmap of the overlay window, taking into account the alpha transparency of the overlay window, both of which are known within the overlay application.

It is an advantage of providing an overlay application with a built-in print-screen function, because the overlay application is able to compensate for the alpha mixing due to the semi-transparent overlay. This offers the user the very great advantage that a screenshot of the underlying applications can be taken without temporarily deactivating the overlay application, thus typically avoiding a light flash that typically occurs when a darkening overlay is temporarily deactivated. This flash can cause temporary blindness and / or eye fatigue.

In one embodiment, the method further comprises step d) of: storing the third bitmap in a non-volatile memory or in a storage device, optionally after format conversion and / or after image compression.

It is an advantage that the overlay application makes it possible to save the screenshot thus taken in a storage device, for example by merely clicking a button. In preferred embodiments, the third image is stored as a compressed image file, for example, as a JPEG file. The overlay application can make it possible for the user to choose the folder location and / or the compression ratio. The overlay application can assign an automatically generated file name, for example based on a counter value, or based on time and date. All this is extremely useful for a user.

BE2018 / 5041

Preferably, the overlay application also allows the user to choose whether or not to include the entire screen, or only the work area (thus omitting the taskbar).

In one embodiment, the method further comprises step e) of: copying the third bitmap to a clipboard of an operating system running on the computing device.

This is comparable to the print-screen button that can be found on many keyboards, but with the important difference that the image is compensated for alpha mixing with the overlay bitmap. The bitmap in the clipboard can then be used in the ways known in the art, for example to be processed in a graphical application (e.g. Paint.Net) or to be pasted in a PowerPoint document, etc.

In one embodiment, step c) comprises using the following set of formulas, or an equivalent set of formulas: T = 1-ct, and R3 [x, y] = [R2 [x, y] - R1 [x, y] * (1T) j / T, and G3 [x, y] = [G2 [x, y] - G1 [x, y] * (1T)] / T, and B3 [x, y] = [B2 [x , y] - B1 [x, y] * (1T)] / T, where (R1, G1, B1) are color components of a pixel at a location (x, y) of the first bitmap to be overlayed, and where ( R2, G2, B2) are color components of a pixel at the corresponding location (x, y) of the second bitmap taken as a screenshot, and where (R1, G1, B1) are color components of a pixel at the corresponding location (x , y) of the third bitmap, and where a is the alpha transparency value, and T is a transparency value.

According to a 7th aspect, the present invention provides a method that combines the characteristics of a method according to one of the 1st to 4th aspect with the characteristics of a method according to the 5th aspect.

According to an 8th aspect, the present invention provides a method that combines the characteristics of a method according to one of the 1st to 4th aspect with the characteristics of a method according to the 6th aspect.

According to a 9th aspect, the present invention provides a computer device, comprising: at least one central processing unit, and a first memory connected to the at least one central processing unit for storing therein computer-executable instructions; computer-executable instructions comprising code fragments for performing an overlay method according to one of the 1st to the 8th aspect.

The computer-executable instructions may further comprise computer-executable instructions configured to generate a graphic image in response to the operating system and / or one or more applications.

The computer-executable instructions may further comprise an operating system (O / S) with a graphical user interface (GUI) that provides only a single mouse pointer, and one or more applications selected from the group consisting of: a web browser application, a worksheet20

BE2018 / 5041 application, a PDF document viewer, a PDF document editor, a text viewer and a word processor.

By computer device is not only meant a personal computer or a desktop computer or a laptop or a tablet computer, but also portable devices, such as a PDA or a smartphone or an eReader device.

In one embodiment, the computer device further comprises a graphic processing unit (GPU) with alpha mixing functionality, and a second memory connected to the graphic processing unit for storing graphic information therein; and wherein the overlay code fragments are configured to use the graphics processor to perform at least alpha blending, and optionally also time multiplexing.

According to a 10th aspect, the present invention also provides a computer system comprising: a computer device according to the 9th aspect; at least one pointing device connected to the computer device, the pointing device being movable by a user, the computer-executable instructions being further configured to receive input data indicative of movements of the pointing device; at least one display device connected to an output of the computer device, for displaying the graphic image mixed with the overlay image.

The pointing device can be, for example, a mouse device, or a trackball or a touchpad.

Preferably, the display device has a screen resolution of at least 1920 x 1080 pixels, or at least 2560 x 1440 pixels, or at least 3840 x 2160 pixels.

The executable instructions for receiving mouse input data are usually referred to as a mouse device driver.

According to an 11th aspect, the present invention also relates to a computer program product for performing a method according to one of the 1st to the 8th aspect on a computer device according to the 9th aspect or a computer system according to the 10th aspect.

Or in other words, according to the 11th aspect, the present invention also provides a computer program product for providing a graphic overlay, the computer program product including executable instructions which, when executed on at least one central processing unit (CPU) of a computer device according to the 9th aspect, or a computer system according to the 10th aspect, cause the computer device to perform a method according to the 1st to the 8th aspect.

According to a 12th aspect, the present invention also provides a portable computing device comprising: a touch screen; at least one central processing unit, and a first memory connected to the at least one central processing unit for storing therein

BE2018 / 5041 save computer-executable instructions; wherein the computer-executable instructions are configured to generate a graphic image containing textual information and to display that graphic image on the touch screen; wherein the computer-executable instructions are further configured to generate a line or an elongated object (e.g., a rectangular object with sharp or rounded edges or with sharp or rounded corners) that covers said textual information; wherein the line or the elongated object contains a plurality of semi-transparent pixels with a transparency level in the range of 1% to 99% or from 2% to 98% or from 5% to 95%, or wherein the line or the elongated object comprises a first plurality contains fully transparent pixels and a second plurality of opaque or semi-transparent pixels that are interleaved (alternately positioned); wherein the computer-executable instructions are further configured to detect a contact position on the touch screen, and to adjust a position of the line or the elongated object in accordance with the detected position.

The device can be, for example, an eReader or a smartphone device.

In one embodiment, the first plurality of pixels and the second plurality of pixels of the bitmap are organized in a pseudo-random pattern, or the first plurality of pixels and the second plurality of pixels of the bitmap are organized in a regular pattern.

In one embodiment, the first plurality of pixels and the second plurality of pixels of the bitmap are organized in a regular pattern according to one of the following options: i) the regular pattern is a 2x2 pattern, and exactly one of four pixels is completely transparent; ii) the regular pattern is a 2x2 pattern and exactly two of the four pixels are completely transparent, the two fully transparent pixels preferably being diagonally opposite each other; iii) the regular pattern is a 2x2 pattern and exactly three of the four pixels are completely transparent.

According to a 13th aspect, the present invention also provides a display device for displaying a graphic image provided by a computer device, the display device comprising: a display panel for generating a visible image; an input port (e.g., a video input port) for receiving the graphic image data from the computer device; an input buffer for storing the graphic image received at the input port, and a texture buffer for storing a texture bitmap, and a frame buffer for storing image data to be displayed on the display panel; a processor adapted to generate the image data to be displayed on the display panel; wherein the texture bitmap comprises a first plurality of pixels that are fully transparent pixels, and a second plurality of pixels that are semi-transparent pixels, preferably with a transparency level of 1% to 99% or 2% to 98% or from 5% to 95 %, wherein the first plurality of pixels and the second plurality of pixels are alternately arranged (interleaved), the processor being adapted to generate the image data to be displayed by copying image data from the input buffer in the case that the corresponding pixel of the

BE2018 / 5041 texture bitmap is a fully transparent pixel, and by alpha mixing image data from the input buffer in the case that the corresponding pixel of the texture bitmap is a semi-transparent pixel.

Preferably the display device is an LCD device or an LCD monitor.

In one embodiment, the first plurality of pixels and the second plurality of pixels of the bitmap are organized in a regular pattern according to one of the following options: i) the regular pattern is a 2x2 pattern, and exactly one of four pixels is completely transparent; ii) the regular pattern is a 2x2 pattern and exactly two of the four pixels are completely transparent, the two fully transparent pixels preferably being diagonally opposite each other; iii) the regular pattern is a 2x2 pattern and exactly three of the four pixels are completely transparent.

In one embodiment, the processor is further adapted to repeatedly adjust a position of the texture bitmap such that pixels of the underlying graphic image are covered (overlayed) by a fully transparent pixel of the first plurality of pixels at a first time, and are covered by a semi-transparent pixel of the second plurality of pixels at a second and optionally third and fourth time points.

According to a 14th aspect, the present invention also provides a display device for displaying a graphic image provided by a computer device, the display device comprising: a display panel for generating a visible image; an input port for receiving said graphic image data from the computer device; an input buffer for storing the graphic image received at the input port, and a texture buffer for storing a texture bitmap, and a frame buffer for storing image data to be displayed on the display panel; a processor adapted to generate the image data to be displayed on the display panel; the processor being adapted to generate said image data as follows: i) copying computer image data from the input buffer at even times at pixel locations for which the sum of the row index and column index is odd, and by alpha mixing computer image data from the input buffer with corresponding pixel data from the texture bitmap at pixel locations for which the sum of the row index and the column index is even; and ii) copying computer image data from the input buffer at pixel locations for which the sum of the row index and column index is even at odd points in time and by mixing computer image data from the input buffer with corresponding pixel data from the texture bitmap at pixel locations for which the sum of the row index and the column index is odd.

Specific and preferred aspects of the invention are included in the appended independent and dependent claims. Features of the dependent claims can be combined with features of the independent claims and with features

BE2018 / 5041 of other dependent claims as indicated and not only as explicitly stated in the claims.

These and other aspects of the invention will become apparent from and clarified with reference to the embodiments described below.

Brief description of the drawings

FIG. 1 shows a schematic block diagram of a classical computer system.

FIG. 2 is a schematic representation of a so-called Z-order of three windows or image planes that can be used in the computer system of FIG. 1.

FIG. 3 shows a schematic block diagram of a computer system similar to that of FIG. 1, when executing an operating system and two applications: a text editor and a specific overlay application, known in the art as LineReader, the latter showing a semi-transparent line across the text editor window, which line can be moved by the user to underline text fragments.

FIG. 4 is a schematic representation of a so-called Z-order of four windows or image planes that can be used in the computer system of FIG. 3.

FIG. 5 shows a schematic block diagram of a computer system similar to that of FIG. 1, when running an operating system and two applications: a text editor and a specific overlay application known in the art as F.Lux, the latter showing a semi-transparent screen-filling overlay image over the desktop window and the text editor window.

FIG. 6 is a schematic representation of a so-called Z-order of four windows or image planes that can be used in the computer system of FIG. 5.

FIG. 7 shows a schematic block diagram of an embodiment of a computer system according to the present invention. The computer system of FIG. 7 contains a specific overlay application for implementing a specific overlay method. The overlay application, when executed in the computer system of FIG. 7, shows a semi-transparent overlay comprising at least two semi-transparent elements: (i) a horizontal line or beam that extends over substantially the entire width of the screen, and (ii) a vertical line or beam that extends over substantially the extends the height of the screen. The horizontal and vertical lines are movable in accordance with movements of the input device.

FIG. 8 is a schematic representation of a Z order of four windows or image planes that can be used in the computer system of FIG. 7.

FIG. 9 shows a schematic block diagram of another computer system according to an embodiment of the present invention. The computer system of FIG. 9 contains a specific overlay application configured to overlay at least two semi-transparent

BE2018 / 5041 elements: i) a line, and ii) a so-called perforated bitmap. The line is movable in accordance with movements of the input device.

FIG. 10 is a schematic representation of a Z order of four windows or image planes that can be used in the computer system of FIG. 9.

FIG. 11 shows a variant of the computer system of FIG. 9.

FIG. 12 is a schematic representation of a Z order of four windows or image planes that can be used in the computer system of FIG. 11.

FIG. 13 shows a plurality of exemplary screenshots (screen recordings). Each row shows a series of five images corresponding to an alpha transparency or alpha blend value a of 100%, 80%, 60%, 40% and 20%, respectively. Each of these images contains a text fragment that is overlayed (covered) by two lines and / or a monochrome bitmap. Two lines are used for illustrative purposes, to show both marking and underlining of text in the same drawing.

In FIG. 13 (a), each text fragment is overlayed by two red lines with (R, G, B) = (255.0.0). The rest of the overlay window is completely transparent.

In FIG. 13 (b), each text fragment is overlayed by a bitmap that contains light gray pixels with (R, G, B) = (192,192,192).

In FIG. 13 (c), each text fragment is overlayed by a bitmap containing dark gray pixels with (R, G, B) = (64, 64, 64).

In FIG. 13 (d), each text fragment is overlayed by a mere combination of the two red lines as in FIG. 13 (a) and through a light gray bitmap as in FIG. 13 (b).

In FIG. 13 (e), each text fragment is overlayed by a mere combination of the two red lines as in FIG. 13 (a) and through a dark gray bitmap as in FIG. 13 (c).

In FIG. 13 (f) to FIG. 13 (i), each text fragment is covered by two red lines as in FIG. 13 (a) and the remaining area is covered by a so-called perforated bitmap as illustrated in FIG. 12, wherein 50% of the pixels are fully transparent pixels arranged in a checkerboard pattern, and the other 50% of the pixels are light gray pixels with (R, G, B) = (192,192,192), as can be provided by overlay methods according to embodiments of the present invention.

In FIG. 13 (g), each text fragment is overlayed by two red lines as in FIG. 13 (a) and through a so-called perforated bitmap as illustrated in FIG. 12, wherein 50% of the pixels are fully transparent pixels arranged in a checkerboard pattern, and the other 50% of the pixels are dark gray pixels with (R, G, B) = (64, 64, 64) as may be provided by overlay methods according to embodiments of the present invention.

In FIG. 13 (h), each text fragment is overlayed by two red lines as in FIG. 13 (a) and through a so-called perforated bitmap as illustrated in FIG. 12, where 50% of the pixels

BE2018 / 5041 are fully transparent pixels arranged in a checkerboard pattern, and the other 50% of the pixels are black pixels with (R, G, B) = (0, 0, 0), as can be provided by overlay methods according to embodiments of the present invention.

In FIG. 13 (i), each text fragment is overlayed by two red lines as in FIG. 13 (a) and through a so-called perforated bitmap as illustrated in FIG. 12, wherein 50% of the pixels are fully transparent pixels arranged in a checkerboard pattern, and the other 50% of the pixels are white pixels with (R, G, B) = (255, 255, 255) as may be provided by overlay methods according to embodiments of the present invention.

FIG. 14 (a) schematically illustrates what happens to text information composed of originally black text pixels and originally white background pixels when these pixels are overlayed by a bitmap containing 100% black pixels with (R, G, B) = (0, 0, 0) ), for three different alpha values.

FIG. 14 (b) schematically illustrates what happens to text information composed of originally black text pixels and originally white background pixels, when these pixels are overlayed by a bitmap containing 100% white pixels with (R, G, B) = (255, 255, 255 ), for three different alpha values.

FIG. 15 (a) schematically illustrates what happens to text information composed of originally black text pixels and originally white background pixels, when these pixels are overlayed by a bitmap containing 50% fully transparent pixels and 50% black pixels with (R, G, B ) = (0, 0, 0), arranged in a checkerboard pattern, for three different alpha values.

FIG. 15 (b) schematically illustrates what happens to text information composed of originally black text pixels and originally white background pixels, when these pixels are overlayed by a bitmap containing 50% fully transparent pixels and 50% white pixels with (R, G, B ) = (255, 255, 255) arranged in a checkerboard pattern for three different alpha values.

FIG. 16 to FIG. 19 show four examples of a larger text fragment.

FIG. 16 shows the text fragment containing black text on a white background as can be represented by a classical PDF viewer.

FIG. 17 shows the text fragment of FIG. 16, overlayed by a blue line segment containing pixels with the color (R, G, B) = (0.0.255), and with the transparency level of the overlay window set to 50%.

FIG. 18 shows the text fragment of FIG. 16, overlayed in a manner as described in FIG. 9 and FIG. 10, in particular, using a perforated bitmap with 50% fully transparent pixels, and 50% gray pixels with color value (128, 128, 128) arranged in a checkerboard pattern.

BE2018 / 5041

FIG. 19 shows a schematic block diagram of another computer system according to an embodiment of the present invention, wherein the computer system comprises a specific overlay application that provides an overlay window comprising at least two semi-transparent elements: i) a line, and ii) a so-called perforated texture bitmap . The line is movable in accordance with movements of an input device.

FIG. 20 is a schematic representation of a Z order of four windows or image planes that can be used in the computer system of FIG. 19.

FIG. 21 shows a schematic block diagram of another computer system according to an embodiment of the present invention, wherein the computer system includes a specific overlay application that provides an overlay window comprising at least one semi-transparent object in the form of a so-called perforated texture bitmap.

FIG. 22 is a schematic representation of a Z order of four windows or image planes that can be used in the computer system of FIG. 21.

FIG. 23 shows a schematic block diagram of another computer system according to an embodiment of the present invention, wherein the computer system includes a specific overlay application that provides an overlay window that includes at least one semi-transparent object in the form of a so-called texture bitmap.

FIG. 24 is a schematic representation of a Z order of four windows or image planes that can be used in the computer system of FIG. 23.

FIG. 25 shows the text fragment of FIG. 16, overlayed in a manner as described in FIG. 19 and FIG. 20, using a perforated bitmap with 50% fully transparent pixels, and 50% gray pixels obtained from a texture bitmap, chosen such that the resulting overlayed image has a background with an average color value of approximately (128, 128, 128) for comparison possible with FIG. 16 (the contrast of the texture is adjustable, and can be somewhat exaggerated for illustrative purposes).

FIG. 26 shows the text fragment of FIG. 16, overlayed in a manner as described in FIG. 19 and FIG. 20, wherein a semi-transparent blue line with color (0.0.255) has been added and using a perforated bitmap with 50% fully transparent pixels and 50% gray pixels organized in a checkerboard pattern, the gray pixels being obtained from a texture bitmap.

FIG. 27 shows the exemplary texture bitmap used to display the image of FIG. 25 and FIG. 26, before perforation, before optional color adjustment and before optional contrast adjustment.

FIG. 28 schematically illustrates how overlaying with a perforated bitmap that is shifted back and forth over a single pixel can be used for time multiplexing or time averaging.

BE2018 / 5041

FIG. 29 (a) to (c) show examples of an image fragment obtained by overlaying a graphic image containing black text on a white background, using a method of the present invention displayed on a display device with native (original) resolution of 3840 x 2160 configured to a resolution of 2560 x 1440, with a scaling factor for text and applications of 100%.

FIG. 29 (a) shows a portion of the image of FIG. 18, viewed from a relatively large distance where the human eye does not distinguish individual pixels.

FIG. 29 (b) shows the same image zoomed in by a factor of approximately 350%.

FIG. 29 (c) shows a portion of the same image, further zoomed in by a factor of about 200%.

FIG. 30 (a) to FIG. 30 (c) show substantially the same images as those of FIG. 29 (a) to FIG. 29 (c), displayed on the same display device, again configured with a resolution of 2560 x 1440, but configured with 125% scaling for text and applications.

FIG. 30 (a) shows what the resulting image fragment looks like when viewed from a relatively large distance where the human eye does not distinguish individual pixels.

FIG. 30 (b) shows the same image zoomed in by a factor of approximately 350%.

FIG. 30 (c) shows the same image, further zoomed in by a factor of about 200%.

FIG. 31 shows a flow diagram of overlay methods according to embodiments of the present invention.

FIG. 32 shows a flow diagram of overlay methods according to embodiments of the present invention.

FIG. 33 shows a flow diagram of overlay methods according to embodiments of the present invention.

FIG. 34 shows a simplified high level block diagram of software components and hardware components, located in a computer system, that typically cooperate in performing a method according to the present invention.

FIG. 35 shows an exemplary user interface window as can be used by an overlay application according to the present invention.

FIG. 36 shows a schematic block diagram of another computer system according to an embodiment of the present invention, with a specific overlay application that provides an overlay window with a movable object having a so-called perforated bitmap. The line is movable in accordance with movements of the input device.

FIG. 37 is a schematic representation of a Z order of four windows or image planes that can be used in the computer system of FIG. 36.

FIG. 38 shows a schematic block diagram of another computer system according to an embodiment of the present invention, with an overlay application having an overlay window

BE2018 / 5041 provided with a movable object in the form of a perforated cross, movable in accordance with movements of the input device.

FIG. 39 is a schematic representation of a Z order of four windows or image planes that can be used in the computer system of FIG. 38.

FIG. 40 shows a schematic block diagram of another computer system according to an embodiment of the present invention, with an overlay application that provides an overlay window with a movable object in the form of a horizontal line extending the entire width of the screen, and which is movable in accordance with movements of the input device.

FIG. 41 is a schematic representation of a Z order of four windows or image planes that can be used in the computer system of FIG. 40.

FIG. 42 shows a schematic block diagram of another computer system according to an embodiment of the present invention, with an overlay application providing an overlay window with a vertical line defining a left area and a right area of the screen, and with a horizontal line extending extends over the width of the left area, and which is vertically movable in accordance with movements of the input device when the mouse cursor is in the left area, and which freezes when the mouse cursor is in the right area.

FIG. 43 is a schematic representation of a Z order of four windows or image planes that can be used in the computer system of FIG. 42.

FIG. 44 shows a flow diagram of another overlay method according to embodiments of the present invention.

FIG. 45 shows a schematic block diagram of a portable device such as, for example, an eReader or a smartphone adapted to display textual information overlayed by a semi-transparent line, according to an embodiment of the present invention.

FIG. 46 shows a schematic block diagram of another computer system according to an embodiment of the present invention, which can be seen as a variant of FIG. 21, wherein the computer system provides a graphic overlay image in the form of a so-called perforated texture bitmap overlayed by the display device.

FIG. 47 is a schematic representation of a Z order of three windows or image planes that can be used in the computer system of FIG. 46, and above that a fourth semi-transparent overlay window provided by the display device.

FIG. 48 shows a schematic block diagram of another computer system according to an embodiment of the present invention, which can be seen as a variant of FIG. 46, wherein the computer system provides a graphic overlay image in the form of an unperforated texture bitmap that is overlayed by the display device.

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FIG. 49 is a schematic representation of a Z order of three windows or image planes that can be used in the computer system of FIG. 48, and above a fourth semi-transparent overlay window provided by the display device.

FIG. 50 shows a flow diagram of another computer-implemented method according to an embodiment of the present invention.

FIG. 51 shows a flow diagram of another computer-implemented method according to an embodiment of the present invention.

Detailed description of illustrative embodiments

The present invention will be described with respect to particular embodiments and with reference to certain drawings, however, the invention is not limited thereto but is only limited by the claims. The figures are only schematic and non-limiting. In the drawings, the size of certain elements may be exaggerated and not drawn to scale for illustrative purposes. The dimensions and the relative dimensions sometimes do not correspond to the current practical embodiment of the invention.

Furthermore, the terms first, second and the like in the description and in the claims are used to distinguish similar elements and not necessarily for describing a sequence, neither in time, nor spatially, nor in ranking, or in any other way. It is to be understood that the terms used in such a manner are suitable under interchangeable conditions and that the embodiments of the invention described herein are capable of operating in a different order than described or depicted herein.

It is to be noted that the term comprising, as used in the claims, is not to be interpreted as being limited to the means described thereafter; this term does not exclude other elements or steps. It can therefore be interpreted as specifying the presence of the listed characteristics, values, steps or components referred to, but does not exclude the presence or addition of one or more other characteristics, values, steps or components, or groups thereof. Thus, the scope of the term a device comprising means A and B should not be limited to devices that consist only of components A and B. It means that with respect to the present invention, A and B are the only relevant components of the device.

Reference throughout this specification to one embodiment or an embodiment means that a specific feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, occurrence of the expressions in one embodiment or in an embodiment at various places throughout this specification may not necessarily all refer to the same embodiment, but may do so. Furthermore, the specific characteristics, structures or

BE2018 / 5041 characteristics can be combined in any suitable manner, as would be apparent to a person skilled in the art based on this disclosure, in one or more embodiments.

Similarly, it should be appreciated that in the description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together into a single embodiment, figure, or description thereof for the purpose of streamlining disclosure and assisting in understanding one or several of the various inventive aspects. In any case, this method of disclosure should not be interpreted as a reflection of an intention that the invention requires more features than explicitly mentioned in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all the features of a single prior disclosed embodiment. Thus, the claims following the detailed description are hereby explicitly included in this detailed description, with each independent claim as a separate embodiment of the present invention.

Furthermore, while some embodiments described herein include some, but not other, features included in other embodiments, combinations of features of different embodiments are intended to be within the scope of the invention, and constitute different embodiments, as would be understood by those skilled in the art . For example, in the following claims, any of the described embodiments can be used in any combination.

Numerous specific details are set forth in the description provided here. It is, however, understood that embodiments of the invention can be practiced without these specific details. In other cases, well-known methods, structures and techniques have not been shown in detail to keep this description clear.

In this document the terms alpha mixing or mixing or mixing (of images or bitmaps) are used as synonyms. In the context of graphic overlay, there is a higher-lying image (with a higher Z-order) and a lower-lying image (with a lower Z-order). The mixing can be done in hardware and / or software, and is based on a parameter called alpha mixing value a, which refers to the level of mixing of the two images, where a = 0% means that the original image is not mixed with the overlay image (or that the overlay image is completely transparent), and where ct = 100% means that the resulting pixel value is that of the overlay image (or that the overlay image is completely opaque) except for fully transparent pixels. The alpha-mixing value can be expressed on a scale from 0 to 255, where ct = 255 corresponds to a = 100% and a = 0 corresponds to a = 0%. For example, alpha mixing can be used to fade in or fade out a graphic image. In the context of the

BE2018 / 5041, the present invention is also a second parameter involved in mixing, designated by the term TransparentColorValue. If a pixel of the overlay image has this predefined (false color or pseudo-color) value, then this pixel is treated as completely transparent. Fully transparent pixels are typically used, for example, when displaying a rectangular image with rounded edges and / or with rounded corners. Alpha blending and fully transparent pixels are both well known in the art.

When reference is made in the present invention to a color of a pixel, not only the hue is meant (e.g., red or blue or green or yellow), but also its intensity or brightness, unless otherwise specified or clear from the context.

When reference is made in the present invention to a color expressed in R, G, B values, a color value is meant that can be represented by a set of color components, for example by a set of (R, G, B) values representative of a red , a green and a blue color component value, each with a value in the range of 0 to 255. Pure black is represented by (0, 0, 0) and pure white is represented by (255, 255, 255). The Ren G and B values for a gray-scale pixel are the same.

By pixel intensity or brightness or luminance of a pixel represented by a set of (R, G, B) values, is meant a value L that is approximately equal to L = R * 0.3 + G * 0.6 + B * 0, 1 or approximately equal to R * 3/8 + G * 5/8 + B * 1/8, or other formulas known in the art.

Where in the present invention reference is made to a black, gray or white pixel, it is meant a pixel having a color whose R value and G value and B value are equal when the color is expressed in R, G , B values, For example, a black pixel has RGB values (0, 0, 0), a white pixel has RGB values (255, 255, 255), assuming an 8-bit representation has been used.

In this document, the term color of a pixel or value of a pixel refers to the set of color components, for example, a combination of an R, G, and B value. A black or white or gray pixel has equal values for its R, G and B components, and can therefore be represented by the color values (χ, χ, χ). For these pixels, the single number x is also called the value of the pixel.

In this document the expression with color (R, G, B) means the same as with a color that can be expressed in terms of Red, Green and Blue color components, with red = R, green = G, blue = B, each on a scale from 0 to 255.

In this document, the terms display and monitor and screen are used as synonyms, unless explicitly stated, or unless the context clearly indicates otherwise. In the context of the present invention, the display is usually a single physical device.

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In this document, the terms checkerboard pattern and checkerboard pattern are used as synonyms.

In this document, the term perforated bitmap means a bitmap that contains a first plurality of fully transparent pixels and a second plurality of other pixels. In practice, the first plurality of pixels has a predefined pseudo-color value that is recognized by a mixing unit (e.g., a software mixer or a graphics processor) to treat these pixels as completely transparent. The other pixels of the bitmap may all have the same color (monochrome), or may have different colors (e.g., extracted from a texture bitmap or may form a color gradient). The first and second plurality of pixels are preferably arranged in a pattern, e.g. in a checkerboard pattern, such as illustrated in FIG. 10 and FIG. 12 and FIG. 22 and FIG. 37.

By average is meant by averaging spatially or by averaging time, or both averaging spatially as well as by averaging time.

In this document, the size, width, or height of the screen may refer to (i) the size, width, and height of the pixel matrix of the screen (not the border around the pixel matrix), or may refer to (ii) the size, width. and height of the so-called work area, which is the same area as (i) minus the area occupied by the so-called task bar (task bar). The work area is also the area that is usually taken up by an application when it is maximized.

In this document, the terms line or bar are used as synonyms. They can refer to a (relatively small) line segment or block or to a rectangular area that extends over almost the full width or the full height of the screen, or over the full width or the full height of the work area of the screen.

In this document, the terms word processor or text editor should not be interpreted too narrowly, because many so-called word processors (such as, for example, Microsoft Word) also have drawing options. Similarly, the term spreadsheet or worksheet should not be interpreted too narrowly, because many so-called worksheet applications, such as Microsoft Excel, also have graphic options.

In this document the expression means the overlay window is configured in click-through mode (click-through mode) or the overlay window is configured in pass-through mode (pass-through mode) that the overlay window is configured in such a way that events (events) of input devices (such as eg a mouse, keyboard, touchpad, etc.) are sent by the operating system to one or more underlying application windows or to objects thereof, despite the higher Z-order of the overlay application. This applies inter alia to events caused by a button press (button-press) or a button release (button-release) or a button click (button-click) or a scroll event of a mouse wheel, and

BE2018 / 5041 on movements. In the context of the present invention, the overlay application typically comprises one window configured in click-through mode, but preferably also a second, substantially opaque window (optionally with fully transparent pixels), with user interface elements.

In this document, the expression the overlay window is configured in non-click mode that the overlay window is not configured in click-through mode.

In this document, the term work area refers to a portion of the pixel area of a screen, namely, the area that will be occupied by the application 705 when it is maximized. In a Microsoft Windows environment, the work area means the entire pixel area except the so-called taskbar (taskbar), which is usually located at the bottom of the screen, but which can also be located elsewhere.

In this document, the expression a bitmap contains semi-transparent pixels usually means that the bitmap does not only consist of fully transparent pixels (ie contains at least one color pixel and optionally one or more fully transparent pixels), and is located in a window that is configured to be semi-transparent with an alpha transparency in the range of 1% to 99%, but other ways of providing a bitmap with semi-transparent pixels can also be used.

The present invention relates to a method for providing a graphic overlay, and to a computer program product adapted to perform such a method when executed on a computer system, and to a computer system comprising such a computer program product.

The present invention will be explained in more detail for the example of a Microsoft Windows desktop PC running a version of Microsoft Windows as the O / S (e.g., Windows XP or Windows NT or Windows 10 or Windows 12 or later Windows versions that have the same or similar functionality with respect to functions relevant to the present invention, such as alpha gene and overlay), and run on one or more applications selected from the group consisting of: a web browser application, a spreadsheet application, a PDF document viewer , a PDF document editor, a text viewer and a text editor; but the invention is not limited thereto, and can also be used on other computing devices, such as, for example, an Apple computer, or on portable devices such as smartphones, on which respective operating systems and applications run.

Referring to the figures,

FIG. 1 shows a schematic block diagram of a classical computer system 100 comprising a computer device 101 connected to a keyboard 102 and a mouse 103 as

BE2018 / 5041 input devices, and with a monitor or display or screen 104 as the output device. The computer device 101 further typically comprises storage components (e.g., in the form of flash memory or one or more hard disks) that store software (executable machine instructions), in particular, an operating system, device drivers, and one or more applications. The computer device 101 further comprises at least one central processing unit CPU configured to execute program instructions from a multitasking operating system with a graphical user interface GUI (e.g., MICROSOFT WINDOWS 10 available from Microsoft Corporation of Redmond, Wash, US), and one or more software applications such as a text viewer or text editor (eg Microsoft Word or Notepad (Notepad) or WordPad) and / or a PDF document viewer (eg Adobe Acrobat Reader) and / or a PDF document editor (eg Nuance Power PDF), and / or an internet browser (eg Microsoft Internet Explorer or Mozilla FireFox or Google Chrome), and / or other applications.

Inputs from the keyboard 102 and the mouse device 103 are typically handled by device drivers configured to receive information via respective input ports (e.g., a serial port or parallel port or USB port). Such computer systems and application programs and device drivers are known in the art.

In the specific example of FIG. 1, the computer device 101 generates a graphic image that is displayed on the display 104 as indicated by the rectangular area 109 (slightly offset from the display edge shown for illustrative purposes). The graphic image comprises image parts related to a so-called desktop window (in this example visible on the left-hand side of the screen 104), and related to an application window (e.g. MS Word) that shows a text document (in this example on the right-hand side of the screen 104) ). In the specific example of FIG. 1, the desktop window includes an image of a car 107 and three icons 108, each icon representing an application, but this is only an example. Also shown is a so-called mouse pointer 199 or mouse cursor that can take various forms, and which moves in accordance with movements of the mouse device 103, under control of the control system.

FIG. 2 is a schematic representation of a possible Z-order of three windows or image planes 281, 282, 283 that can be used in the computer system of FIG. 1, to obtain the combined image 109 shown on the display 104 of FIG. 1. The first window 281 with the lowest Z-order Z1 is called the desktop window, and is usually generated by the operating system. The second window 282 with a second Z-order Z2 higher than Z1 is associated with application 105, (in the example MS Word), and displays alphanumeric or textual information 106. The third window 283 with a Z-order Z3 higher than Z2 is referred to herein as the mouse bitmap 199. In the example, the mouse bitmap 199 is represented by a relatively small one

BE2018 / 5041 window 283, e.g. with a rectangular shape of about 18x22 pixels, or a square shape of 32x32 pixels, comprising a plurality of first pixels PI showing a white arrow with a black border surrounded or partially surrounded by a plurality of second pixels P2 that are completely transparent pixels. The desktop image 281 and the application image 282 are generally opaque images. The three image planes 281, 282, 283 are combined in known ways, resulting in the combined image shown on the display 104. This combined image can be captured, for example, using a well-known print screen function.

FIG. 3 shows a schematic block diagram of a computer system 300 that may have the same hardware configuration as the system 100 of FIG. 1. The system 300 has storage components that store executable instructions from an operating system with a graphical user interface (e.g., Windows 10) and a text editor application (e.g., MS Word), and with a specific overlay application known in the art. as a LineReader (which can be downloaded from http://www.iconico.com/lineReader/ at the time of writing this document). The overlay application shows a semi-transparent line 310 that follows movements of the mouse pointer 399. The line 310 can be used by a user to underline text fragments 306. In fact, LineReader also comes with a user interface, but that aspect is not relevant to the present invention and is therefore not shown or discussed further.

FIG. 4 is a schematic representation of a possible Z-order of four windows or image planes 481-484 as may be used in the computer system 300 of FIG. 3, to obtain the combined image 309 shown on the display 304 of FIG. 3. As far as the inventors are aware, FIG. 4 is not publicly available in the state of the art, but is a probable implementation.

The first window 481 on Z1 is called the desktop window. The second window 482 on Z2 is associated with application 305 (in the example MS Word) and displays alphanumeric or textual information 306. A third window 483 is associated with the LineReader application and has Z-order Z3 higher than Z2 of the text editor application 305. The mouse bitmap or mouse image plane 399 is located in window 484 with Z-order Z4 higher than Z3.

The desktop image 481 and the application image 482 are generally opaque images. The window 483 contains a small line or bar 310, and is configured in click-through mode and in semi-transparent mode with a configurable alpha-mix value that makes it possible to change the transparency level of the line or bar 310. As in FIG. 2, the mouse image plane 484 has first pixels P1 showing a white arrow with a black border, at least partially surrounded by a plurality of second pixels P2 that are fully transparent pixels. The four image planes 481-484

BE2018 / 5041 are combined in known ways, resulting in the combined image 309 shown on the display 304. A portion of the bar is shown enlarged to show that all the pixels P3 of the line 310 are of the same color, e.g. red or blue.

FIG. 5 shows a schematic block diagram of a computer system 500 similar to that of FIG. 1 when it is running an operating system O / S and two applications: a text editor and a specific overlay application known in the art as F.Lux, (which can be downloaded from https at the time of writing this document : //www.microsoft.eom/en-us/store/p/flux/9n9kdphv91jt), which shows a semi-transparent screen-filling overlay window, and which, according to the same website, was created in 2008, which is almost a decade ago.

FIG. 6 is a schematic representation of a possible Z-order of four windows or image planes 681-684 that can be used in the computer system of FIG. 5, to obtain the combined image 509 shown on the display 504 of FIG. 5. As far as the inventors are aware, FIG. 5 is not publicly available in the state of the art, but is a suspected implementation.

The first window 681 on Z1 is called the desktop window. The second window 682 on Z2 is associated with application 505 (in the example MS Word) and displays alphanumeric or textual information 506. A third window 683 at height Z3 is associated with the F.Lux application and has Z-order Z3 higher than Z2 of the text editor application 505. The mouse bitmap or mouse image plane 599 is located in window 684 with Z-order Z4 higher than Z3.

The desktop image 681 and the application image 682 are generally opaque images. As far as known to the inventors of the present invention, the window 683 contains a monochrome bitmap with pixels P4 which all have the same color. The window 683 is configured in click-through mode (ie, it sends all mouse events to child layers, in this example: to the desktop window 681 or to the text editor window 682, depending on the position of the mouse cursor) and is configured in semi -transparent mode with a configurable alpha mix value. As in FIG. 2, the mouse image plane 684 has first pixels P1 that show a white arrow with a black border, at least partially surrounded by a plurality of second pixels P2 that are fully transparent pixels. The four image planes 681-684 are combined in known ways, resulting in the combined image 509 shown on the display 504.

The computer system of FIG. 3 (with the LineReader application) can be helpful for a user when reading textual information on the screen, but is not ideal when extracting information from tables, or when editing a worksheet.

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FIG. 7 shows a schematic block diagram of a computer system 700 according to an embodiment of the present invention. The computer system comprises a computer device 701, and a keyboard 702 and a pointing device or position device 703 (e.g., a mouse device or a touch pad or a joystick) and a display 704 connected to said computer device 701.

The computer device 701 includes a storage or memory device (not shown) that contains an operating system O / S with a graphical user interface GUI (e.g., Windows XP or Windows NT or Windows 10 or Windows 12 or later versions of Windows), and at least one application selected from the group consisting of: a web browser application, a spreadsheet application, a PDF document viewer, a PDF document editor, a text viewer and a text editor.

The computer device 701 further comprises an overlay application showing a semi-transparent overlay window 883 that comprises at least two semi-transparent elements: i) a horizontal line 721 or beam, and ii) a vertical line 722 or beam. The horizontal line 721 preferably extends over substantially the entire width Wo of the overlay window 883, which is preferably equal to the width Wd of the pixel area or the working area of the screen. The vertical line 722 or beam preferably extends over substantially the entire height Ho of the overlay window 883, which is preferably equal to the height Hd of the pixel area or the working area of the screen, irrespective of the actual size of one or other underlying application window 705 (e.g. MS Excel). The overlay application, even though it is configured in click-through mode, ensures that the horizontal line

721 and the vertical line 722 move in accordance with movements of the input device 703, or more specifically, that the horizontal line 721 moves in accordance with the Y coordinate of the mouse pointer 799 and that the vertical line 722 in accordance with the X coordinate of the mouse pointer 799. Preferably, the horizontal line 721 and the vertical line 722 are positioned such that the mouse pointer 799 is at least partially on both the horizontal line 721 and the vertical line 722, for example such that the pointed end of the mouse pointer 799 is in or near the center of the rectangular intersection of the horizontal line 721 and the vertical line

722. Expressed in simple terms, this embodiment provides an overlay application with a semi-transparent cross that moves with the mouse pointer 799.

FIG. 8 is a schematic representation of a possible Z-order of four windows or image planes 881-884 that can be used in the computer system 700 of FIG. 7, to obtain the combined image 709 shown on the display 704 of FIG. 7.

The first window 881 at height Z1 is called the desktop window. The second window 882 on Z2, larger than Z1, is associated with application 705 (in the example MS Excel), which usually presents alphanumeric and / or textual information organized in rows and columns. A third window 883 is associated with an overlay application according to an embodiment of the

BE2018 / 5041, and has a Z-order Z3 higher than Z2 of the spreadsheet application 705. The mouse bitmap or mouse image plane 799 provided by the O / S with graphical user interface GUI is located in window 884 at Z4, higher than Z3 .

The desktop image 881 and the application image 882 are generally opaque images. The window 883 provides a substantially screen-filling overlay, configured in click-through mode and also configured in semi-transparent mode with a configurable alpha blend value α (also called alpha transparency) in the range of 5% to 95%, or from 10% to 90% or from 20% to 80%, or from 30% to 70%, where ct = O% means that the line is completely transparent, and ct = 100% means that the line is completely opaque. The value of a should not be too low, because otherwise the cross is almost invisible and hard to find. The value of a should not be too high, because otherwise the cross is almost opaque, and the information under the cross obscures. The person skilled in the art and / or the user can find suitable values.

Preferably, the overlay application also has another window (not shown in FIG. 7 and FIG. 8, but see, for example, FIG. 35 for an example) as a user interface. This user interface window is then preferably higher than Z3 of the click-through window 883. Preferably, this user interface window makes it possible to select various characteristics of the cross, such as for example: color, width of the lines forming the cross and transparency level .

Referring back to FIG. 8, is a majority portion of the semi-transparent window

883 occupied by fully transparent pixels P5. A minority portion of the semi-transparent window 883 is occupied by the movable horizontal line 721 and the movable vertical line 722. The lines 721, 722 can be implemented as purely rectangular areas, with or without an edge (e.g. a black edge), and with or without rounded edges, and with or without other features. The lines 721, 722 may include monochrome pixels, or may include a color gradient. The color of both lines is preferably the same, and adjustable or selectable. In preferred embodiments, the height hh of the horizontal line 721, and the width ww of the vertical line 722 are adjustable. The values of hh and ww are preferably the same (which simplifies user settings), but that is not absolutely required. As in FIG. 2, the mouse image plane 884 has first pixels P1 showing a white arrow with a black border, at least partially surrounded by a plurality of second pixels P2 that are fully transparent pixels. The accumulation of four image planes 881 to 884 is combined in known ways, resulting in the combined image 709 shown on the display 704.

This overlay application is extremely suitable for finding a correct cell, because the horizontal line 721 and the vertical line 722 extend above the respective row and column headings. This allows a user to immediately see whether or not the mouse pointer is positioned on or above the correct cell, without any column headings and / or row39

BE2018 / 5041 headings. This overlay application can be seen as an extremely useful add-on for spreadsheet applications, but can also be used when extracting information from tables presented on web pages. The tool (tool) is especially useful on high resolution screens (with a resolution of at least 1920 x 1080 pixels).

The tool can drastically reduce the cognitive burden of a user trying to find a particular cell located at the intersection of a certain row (with a certain row header) and a specific column (with a specific column header). Without the overlay tool with the semi-transparent cross, many users first provisionally click on a cell in the vicinity of where they think the target cell is likely to be, and then verify that the correct cell was selected by starting from the selected cell (which after the click is highlighted), and then move his or her eyes horizontally to the row headings while trying to stay in the same row as the selected cell, and if the row is not correct, on the cell higher or lower than the click the selected cell, and repeat the process, and then perform a similar check to verify that the selected cell is in the correct column by starting again from the selected cell, and raising his or her eyes, to the column headings, and if the column appears to be incorrect, select a cell to the left or right of the selected cell, and optionally the final selected double-check the cell. This takes time and is very error prone. It is of course possible to use other manners, for example by panning, or by selecting a specific column by clicking on the column heading, or by using freeze panes (a function in Excel around a certain number of rows and / or block columns), but this also takes time, and introduces the risk of inadvertently changing the height of a row, or the width of a column, etc. By contrast, with the overlay tool presented in FIG. 7, the user can simply move the cross to be positioned above the correct row header and column header, and then click to directly select the correct cell. Moreover, the tool makes it possible to quickly double-check the selected position by moving his or her eyes immediately to the row and column headings, without having to try to stay in the same row or column.

Although no objective evaluation tests have been performed, it is expected that the overlay tool can help improve performance and / or concentration for people who frequently work with spreadsheets, and / or that the risk of extracting or inserting information from / into an incorrect cell is drastically is reduced.

The inventors of the present invention are of the opinion that it is not obvious or trivial to arrive at this solution if one takes proper account of the fact that more than 100 million people use daily for almost two decades

BE2018 / 5041 spreadsheets. If the solution proposed herein were obvious, it would have been widely available for many years.

Instead of providing a window 883 with fully transparent pixels P5 and two movable objects in the form of a horizontal line 721 and a vertical line 722, the same visual effect can also be implemented in other ways, for example by providing a window surface 883 with a screen-filling bitmap with pixels with the color of the cross (e.g. red), and by placing on top of this screen-filling bitmap four other bitmaps, each extending from one of the four corners and having fully transparent pixels, and by adjusting the width and height of each of these four rectangles in accordance with the cursor position 799, or in accordance with movements of the pointing device 703, so as to emulate the cross as the area not overlaid by the four rectangular bitmaps; or in other suitable ways.

The computer system of FIG. 3 (with the LineReader application) can help with reading textual information, but does not help to reduce eye fatigue caused by, for example, a clear white background. The computer system of FIG. 5 (with the F.Lux overlay application) can help to reduce eye fatigue, but does not provide a line or bar to underline text. It would be useful to have a single overlay application that offers both functions at the same time.

As far as known to the inventors, there is currently no computer application tool available on the market that provides an overlay that simultaneously (1) allows to reduce the brightness of a bright (e.g. white) background, and ( 2) showing a semi-transparent line or a semi-transparent cross that follows mouse movements. Initial experiments have shown that a mere combination of the overlay surfaces shown in FIG. 4 and in FIG. 6 does not produce acceptable results, as can be understood from FIG. 13 (d) to FIG. 13 (e), due to conflicting requirements. Indeed, for the text information of the underlying document to be easily legible (e.g., by maintaining sufficient contrast), the transparency level of the third window 883 must be sufficiently high (e.g., T> = 80% or ct <= 20% in FIG. 13 (d) to FIG. 13 (e)). At the same time, for the line to be easily recognizable and the text below the line to be readable, the transparency level of the third window 883 must be sufficiently low (e.g., T in the range of 30% to 70%). The exact figures can be discussed, but the expert reader will agree (after implementing the method described above on a computer) that no acceptable or attractive combination can be found, or at least that such a solution is a serious compromise is.

There is a need for a method to simultaneously reduce the brightness of a clear background and to show a semi-transparent line or a semi-transparent cross that follows mouse movements. The combination should be realized in such a way that (1)

BE2018 / 5041 text information retains good readability, both text information that is overlaid by the line and text information that is not overlaid by the line, and that (2) the semi-transparent line can be easily distinguished from the background, but which is still sufficiently transparent to maintain the readability of the text below the line.

The present invention meets this need by providing both a high level of transparency (high T, low ct) for the (e.g., screen-filling) bitmap, and at the same time providing a low level of transparency (low T, high ct) for the line , by perforating the bitmap, for example as illustrated in FIG. 10 and FIG. 29. A perforated bitmap is understood to mean a bitmap with a first plurality of pixels P6 that are completely transparent (e.g., have a pseudo-color value), and with a second plurality of pixels P7 that have one or more true color values. The pixels P7 will be alpha mixed with underlying layers. As can be understood from FIG. 13 (f) to FIG. 13 (i) this combination provides functional results for almost all transparency levels from 5% to 95% and almost every color or intensity of the pixels P7, but a preferred result is obtained for transparency levels of about 30% to about 70%. Depending on the intended use, a user can configure the transparency level to a more preferred level.

The combination of the two properties semi-transparent line to underline textual information to reduce cognitive burden and the semi-transparent bitmap to change the color temperature to reduce eye fatigue, when combined, create a technical challenge related to how a semi -transparent bitmap and a semi-transparent line can be combined such that the transparency level of the bitmap is higher than the transparency level of the line. This presents a technical problem related to image overlay, image blending, semi-transparency, and alpha mixing, which is a problem rooted in computer technology, and the solution proposed by the present invention (using a perforated bitmap) is also rooted in computer technology. This technology can be used to easily read textual information on a screen with less eye strain.

It is further noted that it is not the overlay application that generates or displays textual or alphanumeric information, but the one or more underlying application (s), eg a text editor, a spreadsheet, a web browser etc. The overlay method therefore presents no information.

Even though the overlay application can be run on a standard computer with a standard O / S (e.g., Windows 10 from Microsoft Corporation), the solution proposed herein provides a technical effect related to two different levels of transparency in a single semi-transparent window, which effect is anything but standard, and goes far beyond mere electrons flowing through a transistor. Furthermore, at least part of the functionality can

BE2018 / 5041 can be implemented in software on the central processing unit or units of the computer system, or at least part of the functionality can be implemented in a graphic processing unit (GPU), if present in the computing device, in particular the alpha mixing operation, and / or the time multiplexing as will be further described when discussing FIG. 28.

FIG. 9 shows a schematic block diagram of a computer system 900 according to an embodiment of the present invention. The computer system 900 includes a computer device 901, and a keyboard 902 and a pointing device or position device 903 (e.g., a mouse or a touch pad or a joystick or a stylus) and a display 904 connected to the computer device 901.

The computer device 901 includes a storage device (not shown) or a memory device (not shown) that includes an operating system O / S with a graphical user interface GUI (e.g., Windows XP or Windows NT or Windows 10), and at least one application selected from the group consisting of: a web browser application, a spreadsheet application, a PDF document viewer, a PDF document editor, a text viewer and a text editor. Instead of being stored in the computer device itself, the O / S and / or the at least one application can be downloadable from a server, e.g. via a network interface. (this also applies to other embodiments of the present invention).

The computer device 901 further comprises an overlay application showing a semi-transparent overlay window 1083 comprising at least two semi-transparent elements: i) a so-called perforated bitmap 930 occupying a majority portion of the overlay window 1083, and ii) a block or a line 910 which occupies only a minority portion of the overlay window 1083. The line 910 is movable in accordance with movements of the input device 903. Instead of being stored in the computer device itself, the overlay application can be downloadable from a server, e.g. via a network interface.

The overlay window 1083 is configured in click-through mode and in semi-transparent mode with a predefined or adjustable alpha mix value a.

The bitmap 930 contains a first plurality of pixels P6 that are completely transparent, and a second plurality of pixels P7 with a color value that will be alpha mixed with the graphic image formed by the accumulation of underlying windows (in the example windows 1081 and 1082). In preferred embodiments, the first plurality of pixels P6 are alternately positioned (interleaved) with the second plurality of pixels P7, in a checkerboard pattern, as shown in FIG. 10 (see also FIG. 29). So preferably 50% of the pixels are completely transparent, while the others are 50% semi-transparent. The effect of using this perforated bitmap is that the spatially average color of the bitmap has a seemingly higher level of transparency than the

BE2018 / 5041 case without the perforation. In this way, the apparent transparency of the bitmap 930 is made higher than that of the line 910, despite the fact that both are associated with the same window 1083 which has only a single alpha merge value a.

As was the case for the overlay application of FIG. 7, the overlay application of FIG. 9 usually with a user interface, which is shown in a second, opaque window (not shown in FIG. 10 but see, for example, FIG. 35). In the embodiment of FIG. 10, the user interface will typically allow a user to change the size (height and / or width) of the line 910, the transparency level a, the color of the pixels P3 of the line 910, the color of the second plurality of pixels P7, can adjust.

The overlay application, even though one of its windows 1083 is configured in click-through mode, causes the line 910 to move in accordance with movements of the input device 903. This can be realized, for example, by repeatedly requesting the position of the native mouse pointer 999 to the operating system (eg based on a timer, or based on polling).

Preferably, the line 910 is positioned such that the mouse pointer 999 is near the center of the line, but this is not absolutely required, and the mouse pointer may be slightly offset from this position, e.g. above the line or below the line positioned. Alternatively, the mouse pointer may also be positioned at or near the left end of the line, or at or near the right end of the line. In any case, the overlay application provides a semi-transparent line 910 that moves with the mouse pointer 999, both of which are visible.

FIG. 10 is a schematic representation of a possible Z-order of four windows or image planes 1081-1084 that can be used in the computer system 900 of FIG. 9, to obtain the combined image 909 shown on the display 904 of FIG. 9.

The first window 1081 on Z1 is called the desktop window. The second window 1082 on Z2 is associated with application 905 (in the example a text editor application, e.g. MS Word), and displays alphanumeric or textual information 906. A third window 1083 is associated with an overlay application according to an embodiment of the present invention and has a Z-order Z3 higher than Z2 of the text editor application 905. The mouse bitmap 999 or the mouse image plane is located in window 1084 at Z4, higher then Z3.

The desktop image in the first window 1081 and the application image in the second window 1082 are usually opaque images. The window 1083 provides a substantially screen-filling overlay configured in click-through mode and also configured in semi-transparent mode with a configurable alpha blend value a. A minority portion of the overlay window 1083 is occupied by pixels P3 with the line color (e.g., red), a majority portion is occupied through the perforated bitmap, in the example a bitmap

BE2018 / 5041 with a first plurality of pixels P6 that are fully transparent pixels, and a second plurality of pixels P7 with a predefined constant color. It is noted that such a perforated bitmap can be efficiently implemented by, for example, first generating a small bitmap of for example 64 x 64 pixels (or 100 x 100 pixels or any other suitable size), and then copying or tiling this small bitmap ( tiling) in the substantially screen-filling bitmap 1083, but other ways can also be used. In an alternative embodiment, this functionality can be implemented as a functionality in GPU chips, thus requiring only minimal load on the central CPU of the computing device.

The line 910 can be implemented as a purely rectangular area, with or without a border (e.g., a black border), and with or without rounded edges, and with or without rounded corners, and with or without other features (e.g., with a color gradient).

The overlay application of the computer system 900 is extremely suitable for reading large amounts of text on the screen. In particular, the overlay application can be used to change the color (or color temperature) of the underlying graphic image, and / or its brightness, which can help reduce eye fatigue, and provides a movable line 910 that a user can use to highlight or underline text displayed in one or more underlying windows.

In certain embodiments, the color temperature can be changed to reduce the amount of blue light. In other embodiments, the color temperature can be changed to increase the amount of blue light.

Although the same alpha mixing value a is used for the line 910 as for the bitmap 930, the bitmap 930 is more transparent than the line, viewed from a distance at which the eye does not distinguish individual pixels, but averages pixel information spatially.

For the sake of completeness, it is noted that other perforation patterns were tested (for example, where 4 of the 16 pixels are fully transparent, or 12 of the 16 pixels are fully transparent), but the checkerboard pattern with 50% fully transparent pixels may be preferred as it appears to be the best results to provide in terms of least noticeable artifacts.

FIG. 11 shows a variant of the computer system of FIG. 9, wherein the semi-transparent line 1120 of the overlay application extends over substantially the full width of the screen (e.g., the full width of the pixel area or the full width of the working area of the screen). This implies that the line 1120 only has to follow vertical movements of the input device 1103, not horizontal movements.

BE2018 / 5041

In the example shown, two applications show textual information, for example a PDF document viewer on the left side of the screen, and a text editor window on the right side of the screen. This can be used, for example, when comparing two documents side by side, for example when proofreading a translation, where the source text is in the PDF document and the target text is in the text document. In the example, the window presents

1282 up-to-date Z2 information associated with the text editor application, and presents the window

1283 up to date Z3 information associated with the PDF document viewer.

FIG. 12 is a schematic representation of a possible Z order of four windows or image planes 1281 - 1284 as may be used in the computer system 1100 of FIG. 11, to obtain the combined image 1109 shown on the display 1104 of FIG. 11. The area for the mouse cursor is not shown, and the area for the user interface window of the overlay application (if present) is not shown, so as not to overload the drawings. Preferably, however, the color of the pixels P3 and of the pixels P7, and the transparency level a, and the height of the line 1120 is adjustable via a user interface, for example a user interface similar to the exemplary user interface of FIG. 35 without a slider for selecting the width of the line.

FIG. 13 shows a plurality of exemplary screenshots (screen recordings). Each row shows a series of five images corresponding to an alpha mix value a of 100%, 80%, 60%, 40% and 20%, respectively, corresponding to a transparency value T of the overlay window of 20%, 40%, 60%, respectively 80% and 100%, where ct = 100% or T = 0% means that the overlay image is completely opaque (except for fully transparent pixels), and ct = O% or T = 100% means that the overlay image is completely transparent, and values from 1% to 99% or from 2% to 98% or from 5% to 95% mean that the overlay image is semi-transparent, meaning that the pixels of the overlay image are proportionally mixed with the underlying image (except for full transparent pixels).

Each of the images shown in FIG. 13 (a) to FIG. 13 (e) contains a text fragment overlayed with two red lines with color (R, G, B) = (255, 0, 0). Two lines are used for illustrative purposes, to show both marking and underlining of text in the same drawing.

In FIG. 13 (a) each text fragment is overlayed by two red lines with (R, G, B) = (255, 0, 0). The rest of the overlay window is completely transparent. This series of images shows results that are similar to what would be obtained by the overlay application of FIG. 3. As can be understood, to provide a line that is well suited for marking and / or underlining underlying textual information without obscuring it, the level of transparency should

BE2018 / 5041 preferably in the range of about 30% to about 75%. For lower values of T, the text becomes unreadable. The line is hardly visible for higher values of T. (It is noted that a proper evaluation should be performed on a screen rather than on paper, but the paper version allows understanding of the principles of the present invention).

In FIG. 13 (b), each text fragment is covered (overlayed) with a semi-transparent bitmap containing only light gray pixels with (R, G, B) = (192, 192, 192), and in FIG. 13 (c) each text fragment is covered (overlayed) with a semi-transparent bitmap that only contains dark gray pixels with (R, G, B) = (64, 64, 64). This series of images shows results similar to what would be obtained by the overlay application of FIG. 5. In order to maintain good readability of the underlying text, the transparency level T should preferably be at least about 85% (or ct <= 15%).

In FIG. 13 (d), each text fragment is overlayed (covered) by a mere combination of the two red lines as in FIG. 13 (a) and through a light gray bitmap as in FIG. 13 (b), and in FIG. 13 (e), each text fragment is overlayed (covered) by a mere combination of the two red lines as in FIG. 13 (a) and through a dark gray bitmap as in FIG. 13 (c).

As described above, when the transparency level T is very low (e.g. <30%), the line is not sufficiently transparent and text underneath is concealed; if the transparency level T is mediocre (e.g. from about 30% to about 70% or about 75%), then the line is well visible and sufficiently transparent, but the text is not easily readable; and if the transparency level T is too high (for example, T> 85%), then the text is easy to read, but the line is almost invisible. None of these combinations therefore provide a good solution for both the line and the bitmap.

In FIG. 13 (f), each text fragment is overlayed by two red lines as in FIG. 13 (a) and by a so-called perforated bitmap as described above, wherein 50% of the pixels are fully transparent pixels P6 arranged in a checkerboard pattern, and the other 50% of the pixels are light gray pixels P7, with (R, G, B) = (192, 192, 192). As can be understood from the drawings (but of course this should be evaluated on a real screen), very acceptable results for both the line and the bitmap are obtained for transparency levels T of about 30% to about 75%.

In FIG. 13 (g), each text fragment is covered (overlayed) by two red lines as in FIG. 13 (a) and by a so-called perforated bitmap as described above, wherein 50% of the pixels are fully transparent pixels P6 arranged in a checkerboard pattern, and the other 50% of the pixels are dark gray pixels P7, with (R, G, B) = (64, 64, 64). Once again be very acceptable

BE2018 / 5041 results for both the line and the bitmap obtained for transparency levels T from about 30% to about 75%.

In FIG. 13 (h), each text fragment is overlayed by two red lines as in FIG. 13 (a) and by a so-called perforated bitmap as described above, wherein 50% of the pixels are fully transparent pixels P6 arranged in a checkerboard pattern, and the other 50% of the pixels are black pixels P7, with (R, G, B) = (0, 0, 0). As can be understood, the text overlayed by the perforated bitmap remains surprisingly very well legible, despite the fact that 50% of the bitmap pixels are pure black, thanks to the perforation.

In FIG. 13 (i), each text fragment is overlayed by two red lines as in FIG. 13 (a) and through a so-called perforated bitmap as described above, wherein 50% of the pixels are fully transparent pixels P6 arranged in a checkerboard pattern, and the other 50% of the pixels are white pixels P7, with (R, G, B) = (255, 255, 255). As can be understood, the text overlayed by the perforated bitmap remains surprisingly very well legible, despite the fact that 50% of the bitmap pixels are pure white thanks to the perforation.

As can be understood from all screenshots in FIG. 13 (f) to FIG. 13 (i), it can be understood that the color of the non-fully transparent pixels P7 of the perforated bitmap can be varied over a wide range (from pure black to pure white), and that it is not critical to the readability of the underlying textual information.

Although the inventors do not wish to be bound by any theory, FIG. 14 and FIG. 15 help to better understand the difference between mixing with a monochrome bitmap versus mixing with a perforated bitmap that contains 50% fully transparent pixels. The intensity (I) is shown on the vertical axis, the horizontal axis is transparency T or alpha transparency a, where a + T = 100%.

FIG. 14 (a) illustrates what happens to a graphic image containing text information with Original Text pixels OT (black) with color (0, 0, 0) and Original Background pixels OB (white) with color (255, 255, 255) when this image is overlayed (mixed) with a monochrome bitmap (as in FIG. 6) containing 100% black pixels with color (0, 0, 0), for different values of the transparency T or alpha mix value a.

In general, the result of overlaying or mixing two bitmaps is a color with the following color components:

(Rm, Gm, Bm) = (R1, G1, B1) x (1-T) + (R2, G2, B2) xT [1]

BE2018 / 5041 where Rm, Gm, Bm are the color components of pixels of the resulting image (the mixed image), T is the transparency level, (R1, G1, B1) is the color of a pixel of the first (overlay) bitmap, and (R2, G2, B2) is the color of a pixel of the second (underlying) bitmap.

When mixing with a black monochrome bitmap, then (R1, G1, B1) = (O, 0, 0).

If T = 100%, then originally white background pixels OB (255, 255, 255) and originally black text pixels OT (0.0, 0) remain unchanged after mixing.

If T = 50%, originally white background pixels OB (255, 255, 255) gray pixels MB (127, 127, 127) are omitted from rounding errors, and originally black text pixels remain black MT (0, 0, 0).

If T = 0%, then originally white background pixels OB (255, 255, 255) and originally black text pixels OT (0.0, 0) both become black (0, 0, 0).

This is more or less visualized by the series of FIG. 13 (c), except that in FIG. 13 (c) the monochrome bitmap has pixels P4 with color (64, 64, 64) instead of (0.0, 0).

FIG. 14 (b) illustrates what happens to a graphic image containing text information with Original Text pixels OT (black) with color (0, 0, 0) and Original Background pixels OB (white) with color (255, 255, 255) when this image is overlayed (mixed) with a monochrome bitmap (as in FIG. 6) that contains 100% white pixels with color (255, 255, 255), for different values of the transparency T or alpha mix value a.

The same mixing formula [1] applies, but now (R1, G1, B1) = (255, 255, 255).

If T = 100%, then white pixels (255, 255, 255) and black pixels (0, 0, 0) remain unchanged after mixing.

If T = 50%, then white pixels (255, 255, 255) remain white (255, 255, 255), and black pixels (0,

0, 0) become gray pixels (127,127,127), except for rounding errors.

If T = 0%, then white pixels (255, 255, 255) and black pixels (0, 0, 0) become both (255, 255, 255).

This is more or less visualized by the series of FIG. 13 (b), except that in FIG. 13 (b) the monochrome bitmap has pixels P4 with color (192,192,192) instead of (255, 255, 255).

FIG. 15 (a) illustrates what happens to a graphic image containing text information with Original Text pixels OT (black) with color (0, 0, 0) and Original Background pixels OB (white) with color (255, 255, 255) when this image is overlayed (mixed) with a perforated bitmap (such as in FIG. 10 or FIG. 12) containing 50% fully transparent pixels P6, and 50% black pixels P7 with color (0.0, 0), for different values of the transparency T (or alpha value ct).

In general, the result of overlaying or mixing with a perforated bitmap with 50% fully transparent pixels P6:

BE2018 / 5041 (Rm, Gm, Bm) = (R1, G1, B1) x (1T) + (R2, G2, B2) xT [2] if the overlay pixel is not completely transparent, which is the case for the pixels P7 , (Rm, Gm, Bm) = (R2, G2, B2) [3] if the overlay pixel is completely transparent, which is the case for the pixels P6, so on average (if the number of pixels P6, P7 is each 50%) :

(Rm, Gm, Bm) = 50% * [(R1, G1, B1) x (1T) + (R2, G2, B2) xT] + 50% * (R2, G2, B2) [4] where Rm , Gm, Bm are the color components of pixels of the resulting image (the mixed image), T is the transparency level, (R1, G1, B1) is the color of a pixel of the first (overlay) bitmap, and (R2, G2 , B2) is the color of a pixel of the second (underlying) bitmap.

Specifically, when blending with a perforated black bitmap with 50% fully transparent pixels P6 and 50% black pixels P7, then (R1, G1, B1) = (0, 0.0).

If T = 100%, then white pixels (255, 255, 255) and black pixels (0, 0.0) remain unchanged.

If T = 50%, then white pixels (255, 255, 255) average become gray pixels (191,191,191), and black pixels remain black (0,0, 0).

If T = 0%, then white pixels (255, 255, 255) on average become gray pixels (127,127,127), and black pixels (0, 0, 0) remain black (0, 0, 0).

This is more or less visualized by the series of FIG. 13 (h), if the two lines are omitted.

FIG. 15 (b) illustrates what happens to a graphic image containing text information with Original Text pixels OT (black) with color (0, 0, 0) and Original Background pixels OB (white) with color (255, 255, 255) when this image is overlayed (mixed) with a perforated bitmap (as in FIG. 10) containing 50% fully transparent pixels P6, and 50% white pixels with color (255, 255, 255), for different values of the transparency T or alphamix value a .

The same formulas [2] to [4] apply.

When mixing with a perforated white bitmap with 50% fully transparent pixels P6 and 50% white pixels P7, then (R1, G1, B1) = (255, 255, 255).

If T = 100%, then white pixels (255, 255, 255) and black pixels (0,0,0) remain unchanged.

If T = 50%, then white pixels (255, 255, 255) remain white, and black pixels become average (64, 64, 64).

If T = 0%, then white pixels (255, 255, 255) remain white, and black pixels on average become gray pixels (127,127,127).

This is more or less visualized by the series of FIG. 13 (i), if the two lines are omitted.

BE2018 / 5041

Thus FIG. 14 can help to understand what happens to black text on a white background when it is overlayed by a monochrome (non-perforated) bitmap, as is the case for the movable object, and FIG. 15 can help to understand what happens to black text on a white background when it is overlayed by a perforated bitmap.

The following section explains what happens to black text on a white background when it is overlayed by a red line. The same formula [1] applies, but now it holds that (R1, G1, B1) is (255.0.0).

FIRST EXAMPLE:

As a first example, the colors of the image fragment of FIG. 13 (e) for T = 80% calculated. The original image includes: black text (0, 0, 0) on a white background (255, 255, 255).

The overlay window includes a (non-perforated) monochrome bitmap with black pixels (0.0, 0), and a line with red pixels (255.0.0), and mixing is done with T set to 80%. Using formula [1], it can be calculated that:

- white background pixels overlayed by the black overlay bitmap: (204, 204, 204),

- black text pixels overlayed by the black overlay bitmap: (0, 0, 0),

- white background pixels overlayed by the red line are: 80% * (255, 255, 255) +20% * (255, 0, 0) = (255, 204, 204), which is very difficult to distinguish from (204, 204, 204),

-the black text pixels overlayed by the red line are: 80% * (0, 0, 0) +20% * (255, 0, 0) = (51, 0, 0).

SECOND EXAMPLE:

As a second example, the colors of the image fragment of FIG. 13 (h) for

T = 60% calculated.

The original image includes: black text (0, 0, 0) on a white background (255, 255, 255).

The overlay includes a perforated bitmap with 50% fully transparent pixels P6 and 50% black pixels P7 (0, 0, 0), and a line with red pixels (255, 0, 0), and mixing is done with T set to 60 %. Using formulas [1] to [5], it can be calculated that:

white background pixels overlayed by the perforated bitmap averaged (204, 204, 204), namely (255, 255, 255) for pixels overlayed by fully transparent pixels P6, and (153,153,153) for the pixels overlaid by a black pixel P7;

- black text pixels overlayed by the black overlay bitmap: (0, 0, 0),

- white background pixels overlayed by the red line are: 60% * (255, 255, 255) +40% * (255, 0, 0) = (255,153,153), which is easily distinguishable from (204, 204, 204),

BE2018 / 5041

-the black text pixels overlayed by the red line are: 60% * (0, 0, 0) +40% * (255, 0, 0) = (102, 0, 0).

Comparison of the first and second example (or the sample of FIG. 13 (e) for T = 80% and the sample of FIG. 13 (h) for T = 60%) teaches that:

- in both cases, black text on a white background (0, 0, 0) becomes an average background color of (204, 204, 204);

- in the case of a non-perforated bitmap, text is overlayed by the red line (51, 0, 0) on (255, 204, 204), which text is legible, but the line is very difficult to distinguish from the background from (204, 204, 204), and therefore not very helpful to underline, while in the case of the perforated bitmap text is overlayed by the red line (102, 0, 0) at (255, 153,153), which text is still is very easy to read, but moreover the line can easily be distinguished from the average background of (204, 204, 204).

Tests have shown that (for the settings of FIG. 13 (h), which means: a perforated bitmap with 50% fully transparent pixels and 50% pure black pixels arranged in a checkerboard pattern), very good results are also obtained for many other line colors in addition to pure red, for example a black line with color (0, 0, 0), a blue line with color (0, 0, 255), a dark red line with color (128, 0, 0), a dark blue line with color (0, 0, 128), a dark green line with color (0, 50, 0), a dark teal line with color (0, 51, 102), a green line with color (0, 128, 0 ), etc., in fact for most relatively dark lines, but also for most relatively bright lines, eg a yellow line with color (255, 255, 0), a bright green line with color (0, 255, 0 ), a turquoise line with color (0, 255, 255), a light gray line of (192, 192, 192) etc. Preferably, the line color can be selected by the user via a user interface which enables the user to select from a variety of suitable colors that produce good results.

While the examples in FIG. 13 are provided for an overlay bitmap (perforated or non-perforated) with black, dark gray, light gray or white pixels, the invention is not limited thereto, and the invention also works when these pixels are not grayscale pixels, but are, for example, bluish pixels or yellowish pixels ( e.g. with color (81, 69, 44) or (83, 69, 40) or (86, 69, 35) etc.) or reddish pixels, or basically any other color. In this way the originally white background color can be transformed into a bluish or yellowish or reddish ... background, which can be more pleasant to read. In particular, yellowish pixels tend to provide a paper-like appearance, especially in combination with a texture bitmap (see below), and bluish pixels tend to provide a sky-like or day-like appearance, etc., for both the perforated bitmap and the non-perforated bitmap. This technique can for example also be used to reduce the blue light content

BE2018 / 5041 is transmitted by a display, which according to some sources may influence the sleep of the user.

FIG. 16 to FIG. 18 show three examples of a slightly larger text fragment, allowing a better understanding of how a reader would view the textual information on a screen.

FIG. 16 is a screenshot (screen capture) of a text fragment extracted from US6333753B1, presented by a PDF viewer called Nuance PDF Reader, where the document is scaled to 200% in the PDF viewer, displayed on a display with a native resolution of 3840 x 2160 pixels, configured with a resolution of 2560 x 1440 pixels, and where the text and applications are scaled to 100% in Windows screen settings. FIG. 17 to FIG. 18 is a screenshot of the same text fragment, but overlayed by an overlay application according to the present invention.

FIG. 16 shows an exemplary text fragment that contains black text on a white background. In fact, many applications do not display textual information as pure black pixels, but also use grayscale pixels, especially near the edges of alphanumeric characters. This aspect is known, but is not particularly relevant to the present invention.

FIG. 17 shows the text fragment of FIG. 16, overlayed by an overlay window containing a blue line segment containing pixels with the color (R, G, B) = (0, 0, 255), and with the transparency level T of the overlay window set to 50%. The transparency level T only affects the transparency of the line, not the fully transparent overlay pixels. Such an image can probably also be obtained with the LineReader application, as discussed in FIG. 3 and FIG. 4.

FIG. 18 shows the text fragment of FIG. 16, overlayed by a method according to the present invention, as described in FIG. 9 and FIG. 10. The alpha mixing value is 50%, a minority portion of the overlay image is occupied by a blue line segment with color value before mixing (R, G, B) = (0, 0, 255), a majority portion of the overlay window is occupied by a perforated bitmap, this bitmap having 50% pure transparent pixels P6 and 50% gray pixels P7 with color value before mixing (R, G, B) = (128, 128, 128) arranged in a checkerboard pattern. As can be understood from FIG. 18, the resulting textual information is easy to read, the line can help the user to stay focused, and the line can be easily distinguished from the background.

However, the inventors went one step further, and also experimented with overlaying textures (perforated or non-perforated). Tests have shown that overlaying with certain textures can transform a pure white background (which appears shiny) into a matte

BE2018 / 5041 background, which can be much more pleasant to read. In one experiment, an image was made of a misty sky, a sub-image was extracted, a horizontal and vertical gradient was removed, the average color was adjusted, the contrast between the brightest pixels and the darkest pixels was adjusted, and the sub-image was adjusted as a semi-transparent overlay tiled over the screen, yielding surprisingly good results, in particular because it apparently removes the gleaming white background of most text documents and replaces it with a matte background, while the text remains surprisingly easy to read.

If no semi-transparent line or cross is added in the overlay (eg for underlining text to be read, or for indicating the position of a cell in a table or spreadsheet), good results can be obtained by a relative high transparency value (e.g. T in the range of about 80% to 99% for a non-perforated bitmap, or T in the range of about 60% to 99% for a perforated bitmap).

If a line or cross is added in the overlay window, it may be better to perforate the bitmap as described above. Surprisingly, the texture pattern can even be made very visible with a perforation of 50%, and aesthetically attractive results can be obtained. However, tests have shown that a single texture bitmap may not be suitable for all transparency levels unless some modification of the pixel values is made. In both cases (perforated or not), the contrast of the texture bitmap must be adjusted or adjusted as a function of the transparency level T or alpha-transparency level a of the overlay window.

In preferred embodiments, the transparency level T of the overlay window is selectable or adjustable by the user, and the contrast level of the texture bitmap is automatically adjusted as a first or second order polynomial of the transparency level T. The value of the contrast itself is not critical (this may typically range from about 0.5 times an optimum value to about 2.0 times the optimum value), but it is important that this value is not fixed, but can be adjusted when the transparency of the overlay window is varied, otherwise the texture is too pronounced and disturbing to the reader, or almost invisible and looks almost the same as a monochrome color overlay. Of course it is also possible to use multiple texture bitmaps in the overlay application, but that consumes more memory space, and can be avoided.

The inventors have found that good results, e.g. near-optimal results, are obtained when the contrast is adjusted so that the texture or pattern is hardly visible, or is slightly visible above. If the contrast level below this ideal value range is chosen, a white background is converted into a shiny (eg shiny plastic-like) background without the texture or pattern being noticeable. In the event that

BE2018 / 5041 If the contrast level above this ideal value range is chosen, the pattern or texture becomes dominant and can distract the user. However, if the contrast level is chosen within the ideal value range, the pattern or texture will cause a slight variation of the background color, which is perceived or experienced as a texture or a pattern or a matte color, and this even appears to be the sharpness of the text characters increase below that. The ideal value range can be different for each pattern bitmap, and is preferably also tunable by the user, in addition to the automatic adjustment related to the transparency value T.

FIG. 19 shows a schematic block diagram of a computer system 1900 according to an embodiment of the present invention, which can be seen as a variant of the computer system of FIG. 10 and the computer system of FIG. 12. Most of what has been described above also applies here, except that the overlay image of the computer system 1900 of FIG. 19 comprises at least two semi-transparent elements: i) a (non-perforated) line 1910, and ii) a perforated texture bitmap 1930. The line 1910 is movable in accordance with movements of the input device 1903.

The perforated texture bitmap can be derived from a predefined texture bitmap (see, for example, FIG. 27) by assigning a pseudo-color value corresponding to a predefined full transparency value to half of the pixel locations, that is, the pixels P6, and by optionally changing the average color of the other pixels P8, optionally adjusting the contrast of the pixels P8, and optionally tiling said bitmap to fill the area of the overlay window 2083.

FIG. 20 is a schematic representation of a Z order of four windows or image planes 2081-2084 that can be used in the computer system of FIG. 19.

FIG. 21 shows a schematic block diagram of another computer system 2100 according to an embodiment of the present invention, which computer system comprises an overlay application for providing an overlay window comprising at least one semi-transparent object in the form of a so-called perforated texture bitmap with a first plurality of fully transparent pixels P6 and a second plurality of opaque or semi-transparent pixels P8. This embodiment is a variant of the embodiment of FIG. 21, the line 1910 being omitted.

FIG. 22 is a schematic representation of a Z order of four windows or image planes 2281-2284 that can be used in the computer system of FIG. 21. As described above, the overlay application may also have a second, opaque user interface window (not shown) where a user can select an average color of the pixels P8, and / or the

BE2018 / 5041 alpha transparency value and can reorder, and / or manually adjust a contrast of the texture bitmap, and / or select a texture bitmap from a list of texture bitmaps.

FIG. 23 shows a schematic block diagram of another computer system 2300 according to an embodiment of the present invention, which computer system comprises an overlay application for providing an overlay window comprising at least one semi-transparent object in the form of a so-called non-perforated texture bitmap consisting of a plurality of semi-transparent pixels P8. This embodiment is a variant of the embodiment of FIG. 23, wherein the perforated pixels P6 are omitted.

FIG. 24 is a schematic representation of a Z order of four windows or image planes 2481-2484 that can be used in the computer system 2300 of FIG. 23.

As can be understood from FIG. 14 and FIG. 15, provide embodiments with an overlay application with a perforated texture bitmap (illustrated in FIG. 21 and FIG. 22) for a transparency level T in the range of 0% to 100% on the one hand, and embodiments with an overlay application with a non-perforated texture bitmap (illustrated in FIG. 23 and FIG. 24) for a transparency level T in the range of 50% to 100% on the other hand, (spatial average) comparable results. These embodiments are extremely useful for converting a glossy (e.g., plastic-like) background surface to a matte (e.g., paper-like) background surface, which is more pleasant to read.

FIG. 25 shows the text fragment of FIG. 16, overlayed (covered) by an overlay image using a transparency level T of 50% (or an alpha value of 50%), wherein a minority portion of the overlay image is occupied by a blue line segment (as in FIG. 16) and a majority portion of the Overlay window includes a perforated texture bitmap, the bitmap having 50% fully transparent pixels and the other 50% pixels forming a texture bitmap with an average color value of (R, G, B) = (128, 128, 128). The resulting overlayed image thus has an average color of approximately (224, 224, 224). Comparison of FIG. 25 and FIG. 18 provides an example of the difference between an overlay with a perforated monochrome bitmap, and an overlay with a perforated texture bitmap. This overlay image can be created by the computer system 1900 of FIG. 19.

FIG. 26 shows an example of an overlay image as can be generated by the computer system of FIG. 23, using a non-perforated texture bitmap with an average color of about (61, 61, 61) and using a transparency level of

BE2018 / 5041

T = 80%, resulting in an average background color of the overlayed image of approximately (216, 216, 216). Comparison of FIG. 26 and FIG. 25 demonstrates that the use of a perforated bitmap does not, or does not significantly, impair the image quality, and therefore the readability of the textual information.

FIG. 27 shows the exemplary texture bitmap used to display the image of FIG. 25, before color adjustment, contrast adjustment and perforation. In this example, the texture bitmap was a grayscale image, but the invention is not limited thereto, and colored texture images can also be used.

Experiments have shown that the texture bitmap can easily be transformed into another texture bitmap with a desired color (Rnew, Gnew, Bnew) by treating each of the color components separately, for example using the following formulas or equivalent formulas:

Rnew [x, y] = minmax (0, CF x (Rorig [x, y] -Ravg) + Rnew, 255); [6]

Gnew [x, y] = minmax (0, CF x (Gorig [x, y] -Gavg) + Gnew, 255); [7]

Bnew [x, y] = minmax (0, CF x (Borig [x, y] -Bavg) + Bnew, 255); [8] where Rnew [x, y] is the Red component of the pixel of the new texture bitmap at position (x, y); and Rorig [x, y] is the Red component of the pixel of the original texture bitmap at position (x, y); and CF is the contrast factor (CF = 1 means no contrast increase, CF <1 means reducing the contrast, CF> 1 means increasing the contrast); Ravg is the average Red color component, Gavg is the average Green color component, and Bavg is the average Blue color component of the original texture bitmap; and where minmax (a, b, c) is a function that provides the result b limited to the range of a to c, thus returning the value b unless b <a in which case a is returned, or unless b> c in which case c is returned. CF is a floating point number, but the result of each formula is converted to an integer from 0 to 255 (also called a byte).

CF can be calculated using one of the following formulas, or an equivalent formula:

CF = K + LxT; [9] or

CF = M + N xT + Qx (TxT) [10] where K, L, M, N, Q are predefined constants that may depend on the specifically selected texture bitmap, and T is the transparency level of the overlay window.

Expressed in simple terms, these formulas can be used to shift a histogram of the pixel values of the texture bitmap up or down (e.g. from Ravg to Rnew), and which can broaden or narrow the width of the histogram characteristic.

BE2018 / 5041

FIG. 28 schematically illustrates how overlaying with a perforated bitmap, e.g., a perforated monochrome bitmap or a perforated texture bitmap, which is repeatedly shifted back and forth over a single pixel distance, can be used for time multiplexing or time averaging, in addition to the spatial means.

FIG. 28 (at time t1) shows a pattern consisting of four pixels, two of these pixels being fully transparent pixels P6, the other two pixels being color pixels that are opaque or that will be alpha blended. This 2x2 pixel pattern is typically repeated (tiled) over the entire overlay bitmap.

FIG. 28 (at time t2) shows a pattern similar to that of FIG. 28 (on time tl), but where other pixel locations are completely transparent.

It is interesting to note that the pattern of FIG. 28 (at t2) can be obtained by merely shifting the bitmap of FIG. 28 (on tl) with 1 pixel up, or 1 pixel to the left, or 1 pixel to the right or 1 pixel down. So if the overlay bitmap is deliberately chosen 1 pixel wider and / or 1 pixel higher than the width W and the height H of the overlay window, and if the overlay bitmap is shifted back and forth every frame with 1 pixel position, or every two frames, or every three frames, then the underlying image is overlayed in a time-multiplexed manner. If the multiplexing frequency is sufficiently high (for example, at least 15 Hz or at least 20 Hz or at least 25 Hz or at least 30 Hz), time-multiplexing can reduce visual artifacts caused by overlaying with the perforated bitmap. If the multiplexing frequency is low (for example, less than 10 Hz), pixels on edges may seem to swirl.

It is also possible to use two separate bitmaps, each of W x H size, and to alternately alpha mix with one or the other bitmap, but such an implementation would require more memory and more time to create the two bitmaps, and is therefore not preferred.

FIG. 29 and FIG. 30 have been added for the sake of completeness to show that the principles described above still work, despite further image processing outside the overlay application itself. Experiments have shown that the screen resolution and the scale factor or zoom factor for text and applications selected in the calculator also influence how the final image will look. Two specific examples are shown here, in FIG. 29 (a) - (c) on the one hand and FIG. 30 (a) - (c) on the other hand.

FIG. 29 (a) shows a screenshot of the same image as used in FIG. 18 (with a perforated monochrome bitmap overlay), but with 2 lines, displayed on a display device with a native resolution of 3840 x 2160, configured at a resolution of 2560 x 1440,

BE2018 / 5041 with a scaling factor (or zoom factor) for text and applications of 100%, such as can be selected in the screen resolution dialog in case of the Windows 10 operating system.

FIG. 29 (b) shows the image of FIG. 29 (a), zoomed in by a factor of approximately 350%. Individual pixels can be distinguished in this image. The checkerboard pattern becomes visible but the text remains very legible.

FIG. 29 (c) shows a portion of the image of FIG. 29 (b), further zoomed in by a factor of around 200%, so zoomed in total by a factor of around 700%. In this image the effect of overlaying with a perforated bitmap with 50% fully transparent pixels and 50% semi-transparent pixels is clearly visible. It was very surprising to the inventors that the individual pixels are not, or not significantly, noticeable in FIG. 29 (a), even if they are actually present.

FIG. 30 (a) shows the same image as FIG. 29 (a) displayed on a display device with a native resolution of 3840 x 2160, configured at a resolution of 2560 x 1440, but with a scaling factor (or zoom factor) for text and applications of 125%, as can be selected, for example in the screen resolution dialog in case of the Windows 10 operating system.

FIG. 30 (b) shows the image of FIG. 30 (a), zoomed in by a factor of approximately 350%. Individual pixels can be distinguished in this image, but the checkerboard pattern is less pronounced.

FIG. 30 (c) shows a portion of the image of FIG. 30 (b), further zoomed in by a factor of around 200%, so zoomed in total by a factor of around 700%. In this image, the effect of overlaying with a perforated bitmap with 50% fully transparent pixels and 50% semi-transparent pixels is no longer clearly visible, but instead a 5 by 5 pixel pattern appears to have been added to the image , probably due to filtering related to zooming, performed outside the overlay application, but within the computer device, since a screenshot can be made.

Again, the individual pixels are not, or not significantly, noticeable in FIG. 30 (a), even if they are actually present. The text of FIG. 30 (a) is very easy to read, and the line is easily distinguishable from the background.

It seems to be a matter of taste which of the two images, that of FIG. 29 (a) or that of FIG. 30 (a) is the best. The image of FIG. 29 (a) appears somewhat sharper, that of FIG. (A) appears to exhibit some wrinkle or pattern due to the combined effect of the perforation followed by filtering, which is also aesthetically appealing, as it gives the impression of a matte background. In any case, both images provide text that is easy to read, both text in the background and text below the line, and in both cases the line is easy to read.

BE2018 / 5041 different from the background, and in both cases the average brightness of the white background is reduced, which can lead to less eye fatigue.

Experiments with other scaling factors for text and applications (in particular 150%, 175%, 225%, 250%, 350%) show results similar to those of FIG. 30 (a) to FIG. 30 (c), while scale factors of 200% or 300% appear to yield results similar to those of FIG. 29 (a) to FIG. 29 (c).

FIG. 31 shows a flow diagram of a computer-implemented method according to some embodiments of the present invention. This method is performed by a computer system of FIG. 9, FIG. 11, FIG. 19, FIG. 21, FIG. 36 and FIG. 38.

An overlay window is provided in step 3101.

The overlay window can be configured as an opaque window, which means that this window can have non-transparent pixels and / or fully transparent pixels, but no semi-transparent pixels.

Alternatively, the overlay window can be configured as a semi-transparent window with an alpha transparency a in the range of 1% to 99% or from 2% to 98% or from 5% to 95%, which means that this window is completely transparent pixels and / or semi-transparent pixels, but not completely opaque pixels.

At step 3102, at least one visible object is provided in said overlay window, the at least one visible object comprising a bitmap with a first plurality of pixels P6 that are fully transparent pixels, and a second plurality of pixels P7, P8 that are opaque pixels or semi -transparent pixels (so not completely transparent pixels); and wherein the first plurality of pixels P6 and the second plurality of pixels P7, P8 are interleaved (arranged alternately), for example arranged according to a checkerboard pattern.

In step 3103, the overlay window is configured in click-through mode.

Step 3103 can be performed before step 3102.

In one embodiment, the overlay window is configured as an opaque window, and the second plurality of pixels are P7, P8, opaque pixels.

In another embodiment, the overlay window is configured as a semi-transparent window, and the second plurality of pixels are semi-transparent pixels.

With configured in click-through mode it is meant that the operating system O / S has been informed that input messages (eg caused by mouse and keyboard events) must be sent to one or more applications that are being overlayed, or to components thereof, instead of to the overlay application itself. Or more correctly, if for example the overlay application contains two windows, one user interface window that is not configured in click-through mode and another window that is configured in click-through mode, then the O / S

BE2018 / 5041 send mouse events to the user interface window when the mouse is above this Ul window, and to the one or more underlying applications if the mouse is above the click-through window, but not above the user interface window.

FIG. 32 shows a flow diagram of a more specific method 3200 according to a preferred embodiment of the present invention. This method is performed by a computer system of FIG. 9, FIG. 11, FIG. 19, FIG. 36 and FIG. 38.

In step 3201, an overlay window is provided, and configured as a semi-transparent window with an alpha transparency a in the range of 1% to 99% or from 2% to 98% or from 5% to 95% or from 10% to 90% or from 20% to 80% or from 30% to 70%.

At step 3202, at least one visible object (e.g., a horizontal line) is provided in the overlay window that occupies only a minority portion (e.g., less than 20% or less than 10%) of the area of the overlay window. For example, if the overlay window has a width W and a height H, then the first object can be, for example, a short horizontal line with a length smaller than W / 2 and a height smaller than H / 10, and thus occupy an area that is smaller then WxH / 20; or may be, for example, a horizontal line extending over the entire width W of the overlay window, and having a height smaller than H / 10, thus occupying an area smaller than W x H / 10.

In step 3203, a bitmap, or an object with a bitmap, is provided, which bitmap has a first plurality of pixels P6 that are fully transparent, and a second plurality of pixels P7, P8 with a color value to be mixed with pixels of one or more underlying windows. The second plurality of pixels P7 can all have the same color (perforated monochrome bitmap), or they can have different colors. The colors can form a color gradient, or can form a texture bitmap. The first and second plurality of pixels are interleaved (alternately positioned), e.g. according to a fixed pattern, e.g. a checkerboard pattern. The bitmap can be above the visible object.

In step 3204, the overlay window is configured as a so-called click-through window. The operating system will send input events such as mouse clicks and mouse movements to one or more underlying windows (or to the desktop window).

In step 3205, position information X, Y is obtained from a so-called mouse pointer or mouse cursor, for example in the form of screen coordinates. The mouse cursor position can, for example, be requested from the operating system, for example in the case of the Windows O / S by using the GetCursorPos function. It is an advantage to use these coordinates because this makes it possible to align or position the at least first visible object relative to the mouse cursor. Alternatively, motion information or motion information dx, dy can be obtained from the control system in the form of raw

BE2018 / 5041 input messages, for example by configuring the operating system to send raw input messages, and by configuring the overlay application to receive and process raw input messages. This aspect is explained in more detail in patent application BE2017 / 5895, filed by the same applicant on December 4, 2017, entitled METHOD AND DEVICE AND SYSTEM FOR PROVIDING DUAL MOUSE SUPPORT, or Dutch title: METHOD AND DEVICE AND SYSTEM FOR PROVIDING DOUBLE MOUSE SUPPORT, which document is incorporated herein by reference in its entirety, and to which will be further referred to herein as the co-pending double mouse application. In the event of inconsistencies between the present application and the pending application, the present document prevails.

In step 3206, a position of the at least one visible object (e.g., the X and Y position of a short horizontal line, or the Y position of a large horizontal line) is adjusted in accordance with the obtained mouse cursor position X, Y or in accordance with the motion or displacement information dx, dy.

In the case of a small or large cross, the mouse cursor position is preferably at or near the intersection of the horizontal and vertical line. In the case of a small horizontal line, the mouse cursor may be at the left end or the right end or at the center of the horizontal line, or in any other suitable position.

Steps 3205 and 3206 are repeated, for example triggered by a timer event with a period in the range of 1 ms to 200 ms, e.g. in the range of 2 ms to 100 ms, e.g. equal to about 5 ms or about 10 ms or about 16.7 ms (60 Hz), or about 20 ms or about 25 ms or about 30 ms or about 40 ms or about 50 ms or about 100 ms or about 150 ms. This value is not critical. The smaller this value, the faster the overlay application responds to mouse movements, but the more computing power is required, among other things, for drawing the at least one object at intermediate positions during movement of the input device. The skilled person can find a suitable compromise between fast response time and a reasonable amount of computing power. The overlay application can make it possible for the user to select from at least two predefined values.

FIG. 33 shows a flow diagram of another method 3300 according to an embodiment of the present invention. This method is performed by the computer system of FIG. 7 and the computer system of FIG. 38.

An overlay window is provided in step 3301.

The overlay window can have a bitmap that essentially fills the entire area of the window with fully transparent pixels (as shown in FIG. 7 and in FIG. 38), or can be a

BE2018 / 5041 comprise perforated bitmap (as in FIG. 10 or FIG. 12) or a perforated texture bitmap (as in FIG. 20 and FIG. 22) or a non-perforated texture bitmap (as in FIG. 24).

In case the window comprises fully transparent pixels (as shown in FIG. 7 and FIG. 38), the overlay window 883, 3983 can be configured as opaque or semi-transparent. In case the window comprises a perforated bitmap, the overlay window 883, 3983 is preferably configured as semi-transparent. Preferably the alpha transparency of the semi-transparent window is a value ct in the range of 1% to 99% or from 2% to 98% or from 5% to 95% or from 10% to 90% or from 20% to 80 % or from 30% to 70%.

In step 3302, a first visible and movable object is provided in the overlay window that is in the form of a horizontal line 721, 3821 that occupies only a minority portion (e.g., less than 20% or less than 10%) of the area of the overlay window. The horizontal line preferably extends over the entire width of the overlay window, which preferably extends itself over the entire pixel area of the screen, or over the entire working area of the screen.

In step 3303, a second visible and movable object is provided in the overlay window that is in the form of a vertical line 722, 3822 that occupies only a minority portion (e.g., less than 20% or less than 10%) of the area of the overlay window. The vertical line preferably extends over the entire height of the overlay window, which preferably extends itself over the entire pixel area of the screen, or over the entire working area of the screen.

Together the horizontal line and the vertical line form a cross. If the window comprises a bitmap, the lines are positioned above the said bitmap so that they are visible. In the embodiment of FIG. 7, the horizontal line 721 and the vertical line 722 are monochrome lines, for example with a red or blue or black or purple or yellow color, or another color. In this case, the overlay window is preferably configured as semi-transparent, so that text under lines 721, 722 is visible. In the embodiment of FIG. 38, the horizontal line 3821 and the vertical line 3822 contain a perforated bitmap. In this case, the overlay window 3983 can be configured as semi-transparent or can contain fully transparent pixels.

In step 3304, the overlay window is configured as a so-called click-through window, so that the operating system will send keyboard and mouse events to the underlying window (s), even though the overlay window is above that, and has a higher Z-order.

In step 3305, position information X, Y is obtained from a so-called mouse pointer or mouse cursor, for example in the form of screen coordinates.

Alternatively, motion information related to movements of the pointing device can be obtained from the control system by using raw input messages, in which case the processing of the raw input messages and the actual update of the position of the visual object (and ) is preferably disconnected from each other, for example as explained in more detail in the pending double mouse application.

BE2018 / 5041

In step 3306, the position of the movable objects (e.g., the X coordinate of the vertical line, and the Y position of the vertical line) is adjusted according to the obtained mouse cursor position X, Y or according to the motion information.

The native mouse cursor position is preferably at or near the intersection of the horizontal and vertical lines.

Steps 3305 and 3306 are repeated, for example using a timer interrupt with a period in the range of 1 ms to 200 ms, for example in the range of 2 ms to 100 ms, for example equal to about 5 ms or about 10 ms, or about 16.7 ms (60 Hz), or about 20 ms, or about 30 ms, or about 40 ms, or about 50 ms, or about 100 ms, or about 150 ms.

FIG. 34 shows a simplified high-level block diagram as a possible representation of the software components and hardware components located in a computer system, which generally cooperate in carrying out a method according to embodiments of the present invention, but it is explicitly pointed out that the present invention does not belong to this implementation is limited, and that other implementations can also be used. The main purpose of this block diagram is to show a possible implementation of an embodiment implemented in a Windows-compatible computer.

FIG. 34 shows an overlay application 3474 and an operating system or O / S 3460 (e.g. MICROSOFT WINDOWS 10 available from Microsoft Corporation of Redmond, Wash, US), a graphics accelerator 3425, output interfaces 3480, a display 3492, an input interface 3410, an input pointing device 3401 and a bitmap generator 3420. Other components include, within the O / S 3460, input device drivers 3466 and graphical API (Application Programming Interface) 3440.

FIG. 34 is very similar to FIG. 8 of US 6333753 (B1), which is incorporated herein by reference in its entirety, but especially FIG. 8 thereof and the accompanying description. Since many aspects are already known, they do not need to be explained in full detail again.

The main similarities of the block diagram 3400 of this document and the block diagram of FIG. 8 of US6333753 (B1) are:

* the internal functioning of the video back-end components, the graphic API 3440, and the graphic accelerator 3425 and the output interfaces 3480 can be largely similar to those of the prior art, e.g. the way in which fully transparent pixels are processed , and the way alpha mixing is performed.

The major differences between the block diagram 3400 of this document and the block diagram of FIG. 8 of US6333753 (B1) are:

BE2018 / 5041 * the present invention does not require a mouse with touch sensors, and therefore does not require special device drivers (device drivers) 3466. Instead, traditional device drivers such as, for example, a standard USB mouse driver (mouse driver) can be used;

* the overlay application 3474 of the present invention does not use animated fadein and fade out. Optionally, however, time multiplexing of the perforated bitmap can be used as described above (FIG. 28), in which case a time multiplexing component 3415 is used, which can send new position information of the shifted perforated and / or textured bitmap, for example any frame, or every two frames, or every three frames, or every four frames. The timing is preferably synchronized with the frame rate;

* in the present invention, the bitmap generator 3420 may generate one or more stationary and / or movable objects, such as, for example, a small horizontal line, or a small cross (e.g., comprising a small horizontal line and a small vertical line), or a large horizontal line (which, for example, extends over the entire width of the overlay window), or a large cross (which, for example, comprises a large horizontal line that preferably extends over the entire width, and a large vertical line which preferably extends over the entire height);

* although not shown in FIG. 34, the present invention preferably also provides a user interface window, an example of which is shown in FIG. 35. The user interface window is usually implemented as a second, substantially opaque window (it may comprise fully transparent pixels), and is preferably located (in Zorde) between the overlay window and the mouse cursor surface. Via this user interface window, the user can, for example, set or select or change dimensions of the horizontal line (pixels P3), and / or set or select the desired transparency level T (or alpha transparency value ct), and / or a color set or select monochrome pixels (P7) of the overlay bitmap, and / or set or select an average color of pixels of texture pixels (P8), etc. This user interface window is not configured in click-through mode because it must be able to click and / or keyboard input, and its area is generally reduced, e.g., minimized during normal use of the graphic overlay application.

Although not shown in FIG. 34, the computer device usually executes one or more application programs in addition to the overlay application 3474, such as for example a word processor, a PDF viewer, a web browser, a spreadsheet, etc.

The input positioning device 3401, for example a mouse or a touch pad, is connected via cables 3403 to input interface 3410, for example a USB input interface, which processes and / or forwards signals from the input device to input device drivers 3466 which component within the O / S 3460. The device drivers 3466 interpret the signals produced by the pointing device 3401 and generate response-relevant events.

BE2018 / 5041

In particular, the O / S causes a mouse pointer or mouse cursor to move in accordance with movements of the device 3401, and transmits these events to an application (e.g., a text processor or web browser), since the overlay application 3474 is configured in click-through mode or pass mode.

Bitmap generator 3420 can include the following:

* a horizontal line generator 3422 for generating at least one horizontal line or beam with a predefined or customizable shape (e.g., rectangular with sharp edges or with rounded edges) and size (e.g. width and height) and position and view ( e.g. as a monochrome bitmap, or with a color gradient, or as a perforated bitmap);

* a vertical line generator 3424 for generating at least one vertical line or beam with a predefined or customizable shape (e.g., rectangular with sharp edges or with rounded edges) and size (e.g. width and height) and position and view ( e.g. as a monochrome bitmap, or with a color gradient, or as a perforated bitmap);

* a background bitmap generator 3426 for generating a relatively large bitmap that preferably occupies the entire area of the overlay window, for example as a monochrome bitmap (similar to FIG. 6), or as a perforated bitmap with 50% fully transparent pixels P6 and 50% monochrome pixels P7 (as in FIG. 10 and FIG. 12), or as a perforated bitmap with 50% fully transparent pixels P6 and 50% texture pixels P8 (as in FIG. 20 and FIG. 22), or as a bitmap with 100% fully transparent pixels P5 (as in FIG. 8, FIG. 37 and FIG. 39), or as a bitmap with 100% textured pixels P8 (as in FIG. 24). One or more of these objects can be generated on the fly (gradually), optionally with the help of a graphic API 3440, and / or with the help of a graphic accelerator 3425.

As explained above, in the case that a semi-transparent window is used as the (first) overlay window, the transparency level T thereof is preferably selected in the range of 30% to 75% (or the alpha-mixing value is preferably selected in the range of 25% to 70%), such that underlying document objects are clearly visible (although optionally slightly darkened or textured) through the overlay window.

In the case that time-division multiplexing is used (which is entirely optional), then the time-division multiplexing module or the time-division multiplexing process 3415 will issue instructions, preferably one such instruction for every N display frames (where N is preferably 1 or 2 or 3 or 4), to shift the perforated bitmap back and forth over a number of pixels, preferably an odd number of pixels, e.g. 1 pixel up / down or 1 pixel left / right, such that a particular pixel of the underlying document object alternately is overlayed (covered) by a completely transparent pixel or by a semi-transparent pixel. These instructions will be delivered, as schematically represented by line 3430 and / or line 3413, to O / S 3460, which in turn can pass on these instructions to graphic API 3440 and ultimately to graphic accelerator 3425.

BE2018 / 5041

If no graphics accelerator is used, then, as symbolized by line 3455, graphics API 3440 can deliver graphics output directly to output interfaces 3480 (specifically a standard video card, not shown, therein) which, in turn, will generate appropriate video signals and which provide signals via cables 3486 to display 3492. In this case, computer system 3400 will need to be sufficiently fast to implement the appropriate graphics capabilities in software that would otherwise be provided by accelerator 3425.

Although alpha-transparency functionality is supported by a wide variety of currently existing graphic accelerators, this functionality can be easily simulated in software, in a well-known way, by conventional 2-D (two-dimensional) or 3-D (three-dimensional) graphic APIs , such as D3D (which is a 3-D graphics API produced by Microsoft Corporation as a component of a WINDOWS operating system, where WINDOWS is a registered trademark of Microsoft Corporation), OpenGL (currently available in the art) or GDI (which is historically only a 2-D low-level graphical processing layer, currently produced by Microsoft Corporation and also included as a standard component of a WINDOWS operating system).

In a variant of the block diagram of FIG. 34, the overlay application does not request the position of the native cursor position of the operating system, but further comprises a processor (handler) of raw input messages configured to process raw input messages provided by the operating system and adapted to the extracting motion information dx, dy from said event messages, and for moving at least one movable object, and optionally overruling the native cursor position of the O / S. Although not relevant to the understanding of the present invention, this aspect is described in more detail in the co-pending double mouse application.

The bitmap generator 3420 can generate one or more image data structures, which can be one or more bitmaps, or a set of commands in a language such as Display Postscript or Quickdraw. Regardless of the details, the image data structure must contain sufficient information so that it can be screened (if not already a bitmap) at the display resolution or otherwise processed for display on the display.

FIG. 35 shows an exemplary user interface window as can be used by an overlay application according to the present invention. This user interface window can be displayed as a second, opaque window, on top of the first overlay window 883, 1083, 284, 2083, 2283, 2483, 3783, 3983, or can be displayed, for example, as a very small object (e.g., a rectangular object) with a bitmap containing a logo of the overlay application, or with a text field containing the name of the overlay application, and with a size smaller than 150 x 30 pixels, e.g.

BE2018 / 5041 smaller than 100 x 30 pixels), or can be minimized in the taskbar. The overlay application can be provided to enlarge the user interface window when the mouse moves over the bitmap with the logo. In this way the user interface window is easily accessible, while it does not take up much space on the screen.

FIG. 36 shows a schematic block diagram of another computer system 3600 according to an embodiment of the present invention, with a computer device 3601 having an overlay application for providing an overlay window 3783 with a movable object 3610 having a perforated bitmap. The line 3610 is movable in accordance with movements of the input device 3603. This embodiment offers the advantage that the overlay window 3783 can be opaque, with most pixels being completely transparent pixels, and yet the effect of a semi-transparent line 3610 can be obtained. Such an embodiment may be particularly useful in computing devices that do not have alpha mixing functionality, such as, for example, eReader devices.

FIG. 37 is a schematic representation of a Z-order of four windows or image planes 3781 to 3784 that can be used in the computer system 3600 of FIG. 36.

FIG. 38 shows a schematic block diagram of another computer system 3700 according to an embodiment of the present invention, with a computer device 3801 having an overlay application for providing an overlay window 3983 with a movable object in the form of a perforated cross. The cross is composed of a horizontal line 3821 and a vertical line 3822, and is movable in accordance with movements of the input device 3803.

FIG. 39 is a schematic representation of a Z-order of four windows or image planes 3981-3984 that can be used in the computer system 3800 of FIG. 38.

FIG. 40 shows a schematic block diagram of another computer system according to an embodiment of the present invention, with an overlay application providing an overlay window 4184 with a movable object in the form of a horizontal line 4020, which preferably extends over the entire width of the screen.

The overlay window 4184 is preferably configured as a semi-transparent window, preferably with an alpha transparency in the range of 5% to 95%, or from 30% to 70%, although this is not absolutely required, and the window 4184 can also be configured as opaque, in which case the pixels P5 would be completely transparent pixels.

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The overlay window 4184 comprises a semi-transparent line with pixels P3. An important advantage of this overlay application is that the line can be used to highlight or underline corresponding text fragments in two different applications, for example a PDF source text to be translated positioned on the left side of the screen 4004 and an MS-Word target text that contains the translated text on the right-hand side of the screen 4004. The line 4020 helps to quickly find the context again when switching back and forth between the two documents, for example during proofreading, thereby significantly increasing the cognitive burden of the proofreader reduced.

Since the overlay application is configured in click-through mode, the mouse 4099 can be used to click or drag or scroll anywhere on the screen. In particular, it allows the PDF document to be moved up or down slightly (e.g., by dragging or scrolling) to keep the text fragments therein aligned with corresponding text fragments of the Word document.

The overlay application causes the Y coordinate of the line 4020 to change in accordance with the Y coordinate of the mouse cursor 4099. The Y coordinates may be identical or may be slightly offset such that the line is slightly above or slightly below the mouse cursor appears.

FIG. 41 is a schematic representation of a Z order of five windows or image planes 4181-4185 that can be used in the computer system of FIG. 40.

The embodiment of FIG. 40 and FIG. 41 can be seen as a variant of the embodiment of FIG. 38 and FIG. 39 or as a variant of the embodiment of FIG. 7 and FIG. 8.

In a variant (not shown) of the embodiment of FIG. 40 and FIG. 41, the line 4020 contains a perforated bitmap (as in FIG. 37), or the line contains a color gradient (vertical or horizontal), or the line contains a texture bitmap.

FIG. 42 shows a schematic block diagram of another computer system 4200 according to an embodiment of the present invention, with an overlay application providing an overlay window 4384 comprising a vertical line 4240 defining a left area and a right area of the screen 4204, and a horizontal line segment 4260 that extends across the width of either the left area or the right area.

The overlay window 4384 is preferably configured as a semi-transparent window, preferably with an alpha transparency in the range of 5% to 95%, or from 30% to 70%, although this is not absolutely required, and the overlay window 4384 can also be configured as opaque, in which case the pixels P5 would be completely transparent pixels.

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The horizontal position of the vertical line 4240 may be predefined, e.g. substantially in the center of the overlay window 4384, or may be selectable via a user interface, but is preferably configurable by dragging the line with the mouse cursor 4299. The the latter is not evident if the overlay window 4384 is configured in click-through mode, but is possible, for example, by dynamically configuring the overlay window 4384 in click-through mode or not in click-through mode, depending on whether the mouse cursor is above vertical line 4240 or not.

The overlay application is configured to update the vertical position Y of the horizontal line segment 4260 in accordance with the position of the mouse cursor 4299 or movements of the pointing device or position device, e.g. mouse device 4203, but only if the mouse cursor is in the left area (ie on the left side of the vertical line 4240). When the mouse is in the right-hand area (i.e., on the right-hand side of the vertical line 4240), the horizontal line segment 4260 retains its position (which is also referred to herein as freezing).

An important advantage of this overlay application is that the line segment 4260 can be used to highlight or underline text fragments in a document to be translated (eg a PDF document located on the left side of the vertical line 4240) while working ( with the keyboard 4202 and the pointing device (e.g. mouse device 4203) in a text editor located on the right-hand side of the vertical line 4240. The line segment 4260 helps to quickly find the context again when switching back and forth between the two documents, for example during translation, thereby significantly reducing the translator's cognitive burden.

This overlay application can also be used by proofreaders, using the line segment 4260 to underline or highlight text fragments (by moving the mouse cursor to the left per line or per single line of source text), and then moving the mouse cursor to the right area , and using the mouse cursor 4299 to hover over the target text, and optionally to edit or correct the latter.

FIG. 43 is a schematic representation of a Z order of five windows or image planes 4381-4385 that can be used in the computer system of FIG. 42.

In a variant (not shown) of the embodiment of FIG. 42 and FIG. 43, the line segment 4260 contains a perforated bitmap (as in FIG. 37), or contains a color gradient (vertical or horizontal), or contains a texture bitmap.

In a variant of the embodiment of FIG. 42 and FIG. 43, the line segment 4260 is on the right-hand side of the vertical line 4240, and is movable if the mouse cursor or pointer

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4299 is to the right of the vertical line 4240, and freezes if the mouse cursor or pointer is on the left side of the vertical line 4240. This embodiment is considered particularly suitable for left-handed persons.

FIG. 44 shows a flow diagram of a method used by the computer system 4200 of

FIG. 42 and FIG. 43 can be performed. FIG. 44 shows a computer-implemented method 4400 for overlaying a graphic image in a computing device, the method comprising the steps of:

a) providing 4401 an overlay window 4384, preferably as a semi-transparent window;

b) providing 4402 a first visible object in the form of a vertical line 4240;

c) providing 4403 a second visible object in the form of a horizontal line segment 4260 which is located either on the left side or on the right side of the vertical line 4240;

repeatedly performing the following steps:

d) obtaining 4404 position information X, Y from a mouse pointer or mouse cursor 4299;

e) testing 4405 whether the mouse cursor or pointer 4299 is on or above the vertical line 4240, and if the result of the test is positive, proceed to step f), otherwise continue to step h);

f) if the overlay window is not already configured in non-click-through mode, configuring 4406 of the overlay window 4384 in non-click-through mode (meaning not in click-through mode but in a mode where the operating system keyboard and mouse events to the overlay window or objects will send from it, instead of to underlying applications, if the mouse is positioned above the overlay window);

g) testing whether a mouse button has been pressed, and if the result of this test is true, dragging the vertical line; and go back to step e);

h) if the overlay window is not already configured in click-through mode, configuring 4408 of the overlay window 4384 in click-through mode;

i) adjusting a position of the horizontal line segment 4260 if the mouse cursor or pointer 4299 is on the same side of the vertical line 4240 as the horizontal line segment 4260, and freezing the horizontal line segment 4260 if the mouse cursor 4299 is on the opposite side of the vertical line 4240, and return to step (e).

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This embodiment provides a line segment 4260 that freezes when the mouse cursor is moving or is located on the right side of the vertical line 4240, and that moves along with the mouse cursor when the mouse cursor 4299 is on the left side of the vertical line 4240 or is moving there, or vice versa. Moreover, this embodiment makes it possible to drag the vertical line 4240 in a very intuitive manner. This embodiment is particularly suitable for translators and proofreaders who do not use a Computer Aided Translation Tool (CAT) tool, or to verify a translation outside of the CAT tool.

It is noted that there was a requirement to make the position of the vertical line selectable or configurable, and since this configuration requires user interaction, the logical place to implement this functionality in the user interface window is because that window is capable of keyboard and receive mouse events. However, the inventors came up with the idea that it would be simpler and more intuitive for the user if the vertical line could be dragged, but that was not possible because the vertical line was implemented in a window configured in click-through mode. In an attempt to find a solution to make dragging possible, the inventors experimented with dynamically changing the click-through functionality of the overlay window, not knowing whether, let alone expecting it to work at all, and whether it would work reliably. to work. The experiments surprisingly demonstrated that it is indeed possible to dynamically change the click-through mode of a window depending on the position of the mouse cursor, in particular depending on whether the native mouse cursor is above the area of the vertical line. At least this aspect is not trivial.

In a variant of the method for FIG. 44, the line segment 4260 is on the right side of the vertical line 4240, and is movable if the mouse cursor or pointer 4299 is on the right of the vertical line 4240, and freezes if the mouse cursor or pointer is on the left side of the vertical line 4240 . This embodiment is considered to be especially useful for left-handed translators and proofreaders and writers.

FIG. 45 shows a mobile device such as, for example, an eReader or a smartphone device, which includes a touch screen, and which executes an app or application that displays textual information, for example in the form of an eBook, or a web browser. The textual information is overlayed (covered) by a line 4510 that allows a user to underline or highlight text information that he or she is reading. The line 4510 can be implemented in an overlay window associated with an overlay application or as part of the operating system running on the device, or can be implemented as part of the app or application itself, e.g. the eBook reader or web browser app .

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In one embodiment, the line 4510 is a semi-transparent line created in an overlay window with an alpha transparency in the range of 1% to 99% or from 2% to 98% or from 5% to 95%, preferably in the range of 30% to 70%. The line 4510 may contain a plurality of monochrome pixels (as in FIG. 8), or may include a color gradient (not shown), or may include a texture.

In another embodiment, the line 4510 is formed by, or includes, a bitmap comprising a first plurality of fully transparent pixels P6 and a second plurality of opaque or semi-transparent pixels P7 that are interleaved (alternately positioned) to make the line appear semi-transparent, referred to herein as a perforated bitmap. In case the pixels P7 are opaque pixels, no alpha mixing is required, and yet the line does not obscure the underlying textual information completely.

The line 4510 can be movable automatically, e.g. based on a timer. Preferably, the speed is configurable or adjustable via a user interface (not shown).

The line 4510 may be movable by dragging, in ways known per se in the prior art, based on a user who contacts the screen with his or her finger, and then moves the finger.

The line can help the reader stay focused while reading, despite distractions.

In an embodiment in which the line 4510 extends substantially the entire width of the display of the device 4500, the reader application or the overlay application need only adjust the vertical position (Y) of the line relative to the screen in accordance with user movements on the touch screen.

In an embodiment where the line 4510 extends only a fraction (e.g., less than 50%) of the width of the display of device 4500, the reader application or the overlay application may be adapted to have both a horizontal position X and a vertical adjust position Y of the line, in accordance with movements of a user's finger on the touch screen.

FIG. 46 shows a schematic block diagram of another computer system 4600 according to an embodiment of the present invention, which can be seen as a variant of FIG. 21, wherein the computer system 4600 provides a graphic overlay image 4784 in the form of a so-called perforated texture bitmap overlayed by the display device 4604.

In this embodiment, the computer device 4601 generates the image planes 4781 to 4783, and supplies corresponding image data to the display device 4604, as a conventional computer would, but the display device, instead of simply displaying said computer data on a display panel , overlays said image data with an overlay image 4784 stored in the display device, and displays the result.

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Display devices are well known in the art, in particular stand-alone LCD display devices or stand-alone LCD monitors. Such a display device comprises essentially three parts: an application processor, a memory device that comprises a frame buffer, and a display device that comprises a display controller and a display panel. The application processor is responsible for drawing and generating an image frame, and for storing the generated image frame in the frame buffer in the memory device. The frame buffer is used to store data from pixels on a display screen. The display controller is primarily responsible for reading the data from the pixels from the frame buffer, and sequentially writing the data from the pixels to logic circuits on the display panel corresponding to the pixels. In a process of displaying an image by the display system, the application processor constantly generates a new image frame, and sends the image frame to the frame buffer.

In the context of the present invention, the application processor is adapted to provide an overlay image 4784 over said computer image, the overlay image being a perforated texture bitmap as explained above. In other words, this bitmap 4730 comprises or consists of a first plurality of pixels P6 that are fully transparent pixels, and a second plurality of pixels P8 that are semi-transparent pixels, which pixels P6 and P8 are interleaved (alternately positioned) in a regular pattern, preferably a checkerboard pattern. The actual step of overlaying may include alpha mixing the computer pixels with corresponding pixels of the perforated texture bitmap.

The perforated texture bitmap can be a predetermined bitmap built into the display device, or is preferably a downloadable image, e.g. displayed on the computer device, and captured by the display device upon user request, for example initiated by a print on a button of the display device (not shown), and then stored in a non-volatile memory of the display device for further use. But other means for downloading the texture bitmap have also been considered, for example using a USB interface for inserting a memory stick, or using a wireless connection, for example a Bluetooth connection for establishing a wireless communication with the computer device, in which case the computer device is preferably equipped with a special application for selecting and sending a texture bitmap to the display device.

Optionally, the display device is further adapted to scale and / or resize and / or tile and / or perforate the texture bitmap, although the perforation can also be implicitly implemented by only mixing a subset of the pixels, for example, one pixel for every two pixels according to the checkerboard pattern.

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Preferably there are at least four or five alpha mixing levels, for example corresponding to a mix of 0/4 = 0%, 1/4 = 25%, 2/4 = 50%, 3/4 = 75% and 4/4 = 100 %. More preferably, there are at least eight or nine alpha mix levels, for example corresponding to a mix of 0/8 = 0%, 1/8, 2/8, 3/8, 4/8, 5/8, 6/8, 7 / 8 and 8/8 = 100%.

Optionally, the display device is further adapted to adjust the transparency level and / or the color and / or the contrast of the texture bitmap, for example using some or all of the formulas [6] to [10] based on a predefined color and / or contrast level that may be provided to the display device by a user, using one or more buttons on the display device, or using said special application for configuring the display device using the said wireless connection, eg Bluetooth connection.

Optionally, the processor is further adapted to repeatedly adjust a position of the texture bitmap such that pixels of the underlying graphic image are overlayed by a fully transparent pixel of the first plurality of pixels P6 at a first time t1, and overlayed by a semi transparent pixel P8 of the second plurality of pixels at a second and optionally third and fourth time points t2, t3, t4, for example as explained above, in the discussion of FIG. 28.

Rather than physically shifting the texture bitmap back and forth by a horizontal or vertical distance of, for example, one pixel for each frame, and rather than storing a perforated bitmap, the processor may be adapted to combine the step of simultaneously perforating and time multiplexing, when generating the image to be stored in the frame buffer, e.g. by doing the following:

i) at even times (t2, t4) copying computer image data from the input buffer at pixel locations X, Y for which the sum of the row index X and the column index Y is odd, and by alpha mixing computer image data from the input buffer with corresponding pixel data from the texture bitmap at pixel locations X, Y for which the sum of the row index X and the column index Y is even; and ii) copying computer image data from the input buffer at pixel locations X, Y for which the sum of the row index X and the column index Y is even at odd times (t3, t5) and alpha mixing of computer image data from the input buffer with corresponding pixel data from the texture bitmap at pixel locations X, Y for which the sum of the row index X and the column index Y is odd.

Although this solution requires a special display device, it provides several advantages: this solution can reduce eye fatigue for users, especially when the computer image contains a clear image. It is a further advantage of this solution that it can transform the appearance of a pure white image into a textured image, for example a

BE2018 / 5041 paper-like image, which can be aesthetically more pleasant to read. It is an advantage that the display device performs alpha mixing instead of the CPU of the computer device, so the CPU load is not affected by this overlay. Finally, it is an advantage to use a perforated bitmap instead of a non-perforated bitmap because it requires less computing power, since only a subset of the pixels, for example, only 50% of the pixels of each frame, have to be mixed, while the other pixels without alpha mixing can be passed on.

FIG. 47 is a schematic representation of a Z order of three windows or image planes that can be used in the computer system of FIG. 46, and above, a fourth semi-transparent overlay image is provided by the display device.

FIG. 48 shows a schematic block diagram of another computer system according to an embodiment of the present invention, which can be seen as a variant of FIG. 46, wherein the computer system provides a graphic overlay image in the form of an unperforated texture bitmap that is overlayed by the display device. Everything mentioned with regard to FIG. 46 and FIG. 47 also applies here, except that all pixels of the texture bitmap should be alpha mixed with the pixels of the computer image.

FIG. 49 is a schematic representation of a Z order of three windows or image planes that can be used in the computer system of FIG. 48, and above, a fourth, semi-transparent overlay image provided by the display device 4804.

Referring to FIG. 50 and FIG. 51.

As already discussed in the background section, the F.Lux tool provides a semi-transparent graphic overlay application using a bitmap, in particular a yellowish monochrome bitmap, the color of which is dynamically adjusted over time. Although this tool can help to reduce eye fatigue, the tool has several limitations, for example:

(1) the overlay does not take into account the actual underlying images provided by the underlying applications. Indeed, the inventors found that in order to reduce eye fatigue, some images should be made darker than other, in particular, applications that provide a window with a pure white background (such as MS Paint or MS Word or MS Powerpoint) should be made darker then applications that provide a gray background. Unfortunately, F.Lux does not take this into account. A user could adjust manually, but this is cumbersome.

BE2018 / 5041 (2) many computer users occasionally take a screenshot (screen capture) (eg using the Print-Screen button on the keyboard), but when F.Lux is executed, the colors of such a screenshot are not the true ones colors of the original image stack associated with the underlying applications, but are yellowish or orange in color. A user who wants to take a screenshot could temporarily deactivate F.Lux to take a screenshot, and then reactivate F.Lux, but this is time consuming, but worse, when F.Lux is deactivated, he or she gets the original images presented that are typically much brighter and can cause eye fatigue.

The inventors of the present invention came up with the idea of tackling these problems by the computer-implemented method 5000 shown in FIG. 50, and the computer-implemented method 5100 of FIG. 51.

FIG. 50 is a flow diagram of a computer-implemented method 5000 for overlaying a graphic image in a computing device that can be seen as a variant of the computing device 2300 of FIG. 23 and FIG. 24. The method comprises the steps of:

a) providing 5001 a semi-transparent overlay window with an alpha transparency value a, and comprising a first bitmap bmpl. The first bitmap can be a monochrome bitmap in which all pixels have the same color, or can be a perforated monochrome bitmap, or can be a texture bitmap, or can be a perforated texture bitmap or another suitable bitmap.

The method further comprises a loop wherein the following steps are repeated:

b) taking 5002 of a screenshot, whereby a second bitmap bmp2 is obtained;

d) determining 5003 of at least one feature of the second bitmap bmp2;

e) adjusting 5004 of the alpha transparency value a of the overlay window and / or adjusting one or more pixel values of the first bitmap bmpl based on the at least one determined characteristic.

The first bitmap can be a monochrome bitmap.

The first bitmap can contain a color gradient.

In one embodiment, step d) comprises: determining an average intensity and / or a maximum intensity and / or an intensity histogram of the pixels of the second bitmap bmp2; and includes step e): adjusting the alpha transparency level a such that the average intensity or the maximum intensity or the intensity histogram meets a predetermined criterion.

In one embodiment, step d) comprises: determining average color component values Ravg, Gavg, Bavg and / or a color component histogram of the pixels of the second bitmap bmp2;

BE2018 / 5041 and comprises step e): adjusting one or more pixel values of the first image bmpl such that the average color component or the color component histogram meets a predetermined criterion.

Better results (in terms of less eye strain) can be achieved if the brightness of the room is also taken into consideration. In such an embodiment, step d) further comprises: determining a brightness value as an indication of a brightness in a room in which the computing device performing the overlay method is located, and the adjustment of step e) further takes into account the brightness value. This brightness value can for example be obtained from a light sensor, or can be derived from an image taken by a webcam, or in another suitable manner.

In a specific embodiment, especially suitable for people working with two documents or working on two different displays, step a) further comprises: providing at least one vertical line or bar in the first bitmap bmpl for defining at least two areas comprising a first area and a second area; and step c) comprises determining at least a first feature of the first area and a second feature of the second area; and includes step e): adjusting one or more pixel values of the first region such that the first characteristic meets a first predetermined criterion, and adjusting one or more pixel values of the second region such that the second characteristic meets a second criterion.

In a variant of this method, each of the left and right areas can be further divided by means of a horizontally movable line or beam, which leads to four different areas. Preferably, each of these areas of the first bitmap is monochrome, meaning that the first area has pixels with color value (R1, G1, BI), the value of R1, G1 and BI being determined based on the graphic content of the images below the first area, the second area has pixels with color values (R2, G2, B2) where the value of R2, G2 and B2 is determined based on the graphical content of the images below the second area, etc. These areas can be perforated or non-perforated. Alternatively, the first area contains pixels derived from a first texture bitmap, with a first average color and a first contrast ratio that is derived depending on at least one characteristic of the image (s) that is / are below the first area, the second area contains pixels extracted from a second texture bitmap, with a second average color and a second contrast ratio, etc. Those skilled in the art with the advantage of the present disclosure can easily devise other variants.

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It is also contemplated that the screenshot can be further analyzed, for example to detect the presence of alphanumeric characters, and their size, and / or the presence of a monochrome background surrounding these characters, and to adjust features of a texture overlay bitmap based on it , for example to create a texture bitmap with a sufficiently low contrast so that it does not negatively affect the readability of the characters, and with a sufficiently high contrast so that it is noticeable by the user, and for example a paper-looking effect, or a matte-looking background creates.

FIG. 51 is a flow diagram of a computer-implemented method 5100 for overlaying a graphic image in a computing device that can be seen as a variant of the computing device 2300 of FIG. 23 and FIG. 24. The method comprises the steps of:

a) providing 5101 a semi-transparent overlay window with an alpha transparency value a in the range of 1% to 99%, and comprising a first bitmap bmpl. The first bitmap can be a perforated bitmap or a non-perforated monochrome bitmap, or can be a perforated or non-perforated texture bitmap, or a bitmap with a gradient based or only two color values.

b) taking 5002 of a screenshot, whereby a second bitmap bmp2 is obtained;

c) calculating a third bitmap bmp3 to compensate for the effect of the graphic overlay based on the first bitmap bmpl and the second bitmap bmp2 and the alpha transparency value a.

It is noted that, in the case that the overlay application not only contains a bitmap but also contains one or more movable objects such as, for example, a horizontal line or a vertical line, it is possible to maintain either these visible objects in the recorded image , or to also compensate for these objects whereby these objects are virtually removed from the recorded image. Whether or not to remove the movable objects may be predetermined setting, or may be configurable by a user, for example in the user interface window.

Optionally, the method further comprises step d) of: storing 5104 from the third bitmap bmp3 to a non-volatile memory (e.g. on a memory stick) or on a storage device (e.g. a hard disk or a network drive), optionally after format conversion (eg BMP to PNG) and / or after image compression (eg loss-free or loss-making JPEG compression).

Optionally, the method further comprises step e) of: copying 5105 from the third bitmap bmp3 to a clipboard of an operating system running on the computing device (e.g.:

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MS Windows 10 or a later version with the same or similar functionality). This function is comparable to the print screen button that is present on many keyboards, but with the additional benefit of compensating for alpha mixing. In this way, a user suffering from eye fatigue can work on his computer, and can even take screenshots without having to deactivate the overlay image. This is a very big advantage for such users, both because of reduced eye fatigue and because of time saved.

In order to perform the compensation, use can be made of the following set of formulas, or an equivalent set of formulas:

R3 [x, y] = [R2 [x, y] - R1 [x, y] * (1-T)] / T [11]

G3 [x, y] = [G2 [x, y] - G1 [x, y] * (1-T)] / T [12]

B3 [x, y] = [B2 [x, y] - B1 [x, y] * (1-T) J / T [13]

T = 1a [14] where R1, B1, G1 are color components of a pixel at a location (x, y) of the first bitmap bmpl that is overlaid, and where R2, G2, B2 are color components of a pixel at a location ( x, y) of the second bitmap bmp2 taken as the screenshot, and where R3, G3, B3 are color components of a pixel at a location (x, y) of the third bitmap bmp3, and where a is the alpha transparency value, and T is a transparency value, both expressed as a floating point number in the range of 0.01 to 0.99.

In the case that the first bitmap is perforated, the formulas [11] to [14] need only be applied in the case that the pixel of the first bitmap is not completely transparent.

AND LAST BUT NOT LEAST,

Although individual features have been illustrated in various drawings and in various embodiments of the present invention, it is contemplated that features of various embodiments may be combined as would be obvious to those skilled in the art upon reading this document.

Although all embodiments are shown with a desktop computer and a mouse and a keyboard, other computing devices and / or other input devices can also be used. For example, the mouse device can be replaced with other devices that provide the same or similar function and control, such as a pointing device, a track ball or a joystick or a touch pad or a stylus.

Although the invention has been described primarily for the Microsoft Corporation's Windows operating system, the invention is not limited thereto, and can also be used, for example, on an Apple computer with the Apple OS Macintosh OS, or on a smartphone, or on a eReader, or other devices with an operating system with a graphical user interface.

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The present invention discloses various embodiments, which can be summarized as follows:

1) a computer-implemented method of overlaying with a perforated bitmap.

This can be summarized as follows. A computer-implemented method for overlaying a graphic image in a computing device, comprising the steps of: a) providing an overlay window; b) providing at least one visible object in said overlay window, wherein the at least one visible object comprises a bitmap with a first plurality of pixels that are fully transparent pixels, and a second plurality of pixels that are opaque pixels or semi-transparent pixels ; wherein the first plurality of pixels P6 and the second plurality of pixels are interleaved (alternately positioned), for example in a checkerboard pattern; c) configuring the overlay window in click-through mode. The object is movable in accordance with mouse movements.

2) a computer-implemented method of overlaying with a large cross.

This can be summarized as follows. A computer-implemented method for overlaying a graphic image in a computing device, the method comprising the steps of: a) providing an overlay window; b) providing an elongated horizontally visible object; c) providing an elongated vertically visible object in said overlay window; d) configuring the overlay window in click-through mode; repeatedly f) obtaining position information X, Y from a mouse pointer or obtaining movement information dx, dy from the at least one pointing device; repeatedly g) adjusting a position of the first and second visible object based on the obtained position information or using the motion information. The crotch can be semi-transparent, and can extend over the entire height and width of the screen. Use of this overlay application as an add-on for spreadsheet applications for marking alphanumeric information and / or extracting information from tables.

3) a computer-implemented method of overlaying with a texture bitmap.

4) a computer-implemented method of overlaying with a vertical line to split the screen, and with a horizontal line moving or freezing, also called frozen line herein.

This can be summarized as follows. A computer-implemented method for overlaying a graphic image, comprising: a) providing an overlay window; b) providing a vertical line; c) providing a horizontal line located on the left or right side of the vertical line; repeatedly: d) obtaining position information from a mouse cursor; e) testing whether the mouse cursor is on the vertical line and, if so, continue with step f), otherwise continue with step h); f) configuring

BE2018 / 5041 of the overlay window in non-click-through mode; g) testing whether a mouse button has been pressed and, if so, dragging the vertical line; and go to step d; h) configuring the overlay window in click-through mode; i) adjusting a position of the horizontal line. The vertical line splits the screen and can be dragged. The horizontal line moves or freezes, depending on which side the mouse cursor is moving.

5) a computer-implemented method for dynamically overlaying, taking into account visual aspects (e.g. color and / or brightness) of the underlying applications, referred to herein as automatic adjustment, e.g. automatic darkening.

This can be summarized as follows. A computer-implemented method for overlaying a graphic image in a computing device, the method comprising the steps of: a) providing a semi-transparent overlay window with an alpha transparency value ct in the range of 1% to 99% and comprising a first bitmap; repeatedly performing the following steps: b) taking a screenshot, thereby obtaining a second bitmap; c) determining at least one feature of the second bitmap; e) adjusting the alpha transparency value of the overlay window and / or adjusting one or more pixel values of the first bitmap, based on the at least one determined characteristic. The overlay method may further comprise a vertical blade to define different areas that can be adjusted individually depending on the image content among the areas.

6) a computer-implemented method of overlay while allowing the taking of a screenshot, which screenshot is compensated for the graphic overlay, referred to herein as a compensated screenshot.

This can be summarized as follows. A computer-implemented method for overlaying a graphic image in a computing device, the method comprising the steps of: a) providing a semi-transparent overlay window that has an alpha transparency value a in the range of 1% to 99%, and that includes a first bitmap; b) taking a screenshot, whereby a second bitmap is obtained; c) calculating a third bitmap to compensate for the effect of the graphic overlay based on the first bitmap and the second bitmap and the alpha transparency value a; d) optionally storing the third bitmap in a non-volatile memory or storage device; e) optionally copying the third bitmap to a clipboard of the operating system.

7) A computer-implemented method that combines one or more of methods 1) to 4) and method 5).

For example, the overlay methods with a perforated bitmap can be combined with the automatic adjustment, and the overlay method with a large cross can

BE2018 / 5041 can be combined with the automatic adjustment, and the overlay method with a texture bitmap can be combined with the automatic adjustment, and the overlay method with the frozen line can be combined with the automatic adjustment.

8) A computer-implemented method that combines one or more of methods 1) to 4) and method 6).

For example, the overlay methods with a perforated bitmap can be combined with the compensated screenshot, and the overlay method with a large cross can be combined with the compensated screenshot, and the overlay method with a texture bitmap can be combined with the compensated screenshot, and the overlay method with the compensated screenshot frozen line can be combined with the compensated screenshot.

9) a computer device for performing one of the computer-implemented methods 1) to 8).

10) a computer system comprising a computer device 9).

11) a computer program product for performing one of the computer-implemented methods 1) to 8).

12) a portable device (eg an eReader) with an overlay with a semi-transparent line.

This can be summarized as follows. A portable computing device comprising: a touch screen; at least one processing unit and a first memory for storing computer-executable instructions; wherein the instructions are configured to generate a graphic image containing textual information and to display that graphic image on the touch screen; wherein the instructions are further configured to generate a line or an elongated object that covers said textual information; wherein the line or the elongated object comprises a plurality of semi-transparent pixels with a transparency level of 5% to 95%, or wherein the line or the elongated object contains a first plurality of fully transparent pixels and a second plurality of opaque or semi-transparent pixels, who are interleaved (alternately positioned); wherein the instructions are further configured to detect a contact position on the touch screen, and to adjust a position of the line accordingly. For example an eReader device that displays textual information overlayed by a semi-transparent line.

13) a display device for overlaying with a perforated bitmap,

14) a display device with a movable object that looks semi-transparent due to time-multiplexed overlay.

BE2018 / 5041

It is further explicitly pointed out that embodiments of the present invention can be combined in any suitable manner with embodiments of the co-pending double mouse application.

For example, by adding to the embodiments of the present invention a second pointing device and the associated functionality for obtaining double mouse support, as described in the co-pending application. Or, for example, by adding a special hub and / or a special display device and / or a special video adapter to embodiments of the present invention.

Some of these combined embodiments may be particularly suitable for translators, or proofreaders, or technical writers, or patent attorneys or other professional users who spend many hours in front of a computer screen and often switch back and forth between different documents because the cognitive burden is related the regaining of the current context after switching back and forth between documents can be considerably reduced thanks to the multiple visible objects that are movable through the two (or more) pointing devices, and because eye fatigue related to a bright background light can also be reduced.

BE2018 / 5041

Claims (10)

Conclusions A computer-implemented method (5000) for overlaying a graphic image in a computer with an overlay image, the method comprising the steps of: a) providing (5001) an overlay application that provides a semi-transparent overlay window with an alpha transparency value (ot) in the range of 1% to 99% and comprising a first bitmap (bmpl) with the overlay image; repeatedly performing the following steps: b) taking (5002) a screenshot, whereby a second bitmap (bmp2) is obtained with pixel values corresponding to an alpha mix of the underlying graphic image and the overlay image; c) determining (5003) at least one feature of the second bitmap (bmp2); e) adjusting (5004) the alpha transparency value (ot) of the overlay window and / or adjusting one or more pixel values of the first bitmap (bmpl) based on the at least one particular characteristic. A computer-implemented method according to claim 1, wherein the first bitmap (bmpl) is a monochrome bitmap, or wherein the first bitmap (bmpl) is a bitmap with a first plurality of fully transparent pixels (P6) interspersed with a second plurality of pixels (P7) that are semi-transparent and have a monochrome color value. A computer-implemented method according to claim 1, wherein the first bitmap (bmpl) is a color gradient, or wherein the first bitmap (bmpl) is a bitmap with a first plurality of fully transparent pixels (P6) interspersed with a second plurality of pixels ( P7) that are semi-transparent and have a color gradient as a color value. A computer-implemented method according to any of claims 1 to 3, wherein step c) comprises: determining an average intensity and / or a maximum intensity and / or an intensity histogram of the pixels of the second bitmap (bmp2); and wherein step e) comprises: adjusting the alpha transparency level (ot) such that the average intensity or the maximum intensity or the intensity histogram at a subsequent iteration meets a predetermined criterion. A computer-implemented method according to any of claims 1 to 4, wherein step c) comprises: determining average color component values (Ravg, Gavg, Bavg) and / or color component histograms of the pixels of the second bitmap (bmp2); BE2018 / 5041 and wherein step e) comprises: adjusting one or more pixel values of the first image (bmpl) such that the average color component or the color component histogram meets a predetermined criterion in a subsequent iteration. A computer-implemented method according to any one of claims 1 to 5, further comprising step d) of determining a brightness value as an indication of a brightness in a room; and wherein step e) includes taking the brightness value into account. A computer-implemented method according to any of claims 1 to 6, wherein step a) further comprises: providing at least one vertical line or bar in the first bitmap (bmpl) for defining at least two regions including a first region and a second area; and wherein step c) comprises determining at least a first feature of the first area and a second feature of the second area; and wherein step e) comprises: adjusting one or more pixel values of the first region such that the first characteristic meets a first predetermined criterion, and adjusting one or more pixel values of the second region such that the second characteristic meets to a second criterion. A computer device comprising: - at least one central processing unit (CPU), and a first memory connected to the at least one central processing unit (CPU) for storing computer-executable instructions therein; - wherein the computer-executable instructions comprise code fragments for performing an overlay method according to one of claims 1 to 7. 9. A computer system comprising: - a computer device according to claim 8; - at least one pointing device connected to the computer device, wherein the pointing device is movable by a user, and wherein the computer-executable instructions are further configured to receive input data as an indication of movements of the pointing device; - at least one display device connected to an output of the computer device, for displaying the graphic image mixed with the overlay image. BE2018 / 5041 A computer program product for providing a graphic overlay, the computer program product including executable instructions which, when executed on at least one central processing unit (CPU) of a computer device according to claim 8 or a computer system according to claim 9, cause the computer device a method 5 according to one of claims 1 to 7.