KR101666131B1

KR101666131B1 - Vector Font Rendering with considering sub-pixel pattern

Info

Publication number: KR101666131B1
Application number: KR1020150075998A
Authority: KR
Inventors: 이환용; 도주영
Original assignee: 경북대학교 산학협력단
Priority date: 2015-05-29
Filing date: 2015-05-29
Publication date: 2016-10-14

Abstract

A method of rendering a vector font considering a pattern of subpixels according to the present invention includes the steps of receiving a pattern of a subpixel of a display device from a user and a size of a font and a font; Rendering the font entered by the user in a predetermined size; Determining neighboring pixel groups for each pixel group having a predetermined size in the rendered font image to determine whether or not the pixel group is drawn; And calculating a pixel value by considering a subpixel pattern and assigning an output pixel value to a pixel group that is a thinner one among the pixel groups, and for a pixel group that is not a pixel group that is a thinner among the pixel groups, And calculating an average of the pixels to assign an output pixel value.

Description

[0001] The present invention relates to a method of rendering a vector font considering a sub-pixel pattern,

The present invention relates to a rendering technique, and more particularly, to a method and apparatus for rendering a vector font considering a sub-pixel pattern that improves the rendering quality of a font by calculating pixel values according to a pattern and a sub- .

Rendering refers to the technique of creating a two-dimensional image in consideration of materials such as the shape or color of an object set as input information. That is, it is a computer graphic process of generating a two-dimensional image by inputting numerical information and geometric information. In particular, the process of creating an image by using a font file represented by an outline and attributes such as the size and color of characters and characters presented by the user is referred to as font rendering.

Such a rendering technique is disclosed in the Korean Intellectual Property Office (KIPO) No. 1020090078654, which comprises: (a) acquiring a character image which is a two-dimensional image representing the character in consideration of character data representing the character; And (b) rendering the character image.

And 1020040086740, which is patented in the Korean Intellectual Property Office, which includes sampling actual image data for the contour to be rendered, determining approximate image data for one or more straight segments to approximate the contour to be rendered So that the filter optimally collects the spectral energy of the sampled image data at the center of the region of the spectral domain corresponding to the sample interval in the spatial domain of the sampled image data, Comprising the steps of: filtering linear segments to produce filtered image data; rendering the contour using the filtered image data; and determining whether the width of the approximate image data is greater than the width of the mask of the filter Step When the width of the projected image data is larger than the width of the mask of the filter, it discloses a method of rendering an image comprising the step of filtering the borders (edges) of the approximate image data.

And 1020060107268, which is published in the Korean Intellectual Property Office, discloses a method and system for controlling a graphics system using a font-hinting language in a computing system having access to a set of control points for generating an outline of a graphical object. ) &Lt; / RTI > of the solution.

Among the conventional techniques, hinting is applied to a large number of characters such as an English alphabet where the number of characters is small, by programming rules and conditions necessary for rendering a font and storing them in a font file.

However, in the case of a large number of characters such as Hangul or Hanja, there is a problem that it is very difficult to implement because different rules must be programmed for each character.

Also, in the case of character rendering considering the red (RGB) pattern of the display device, the character is rendered at an image size N times without considering the thickness of the stroke of the character and the sub-pixel pattern, Since all cyan and magenta use the anti-aliasing method of assigning the same value, there is a problem that the rendering quality is low and the efficiency of the software or hardware is low.

Korean Patent Publication No. 1020090078654 Korean Patent Publication No. 1020040086740 Korean Patent Publication No. 1020110018297 Korean Patent Publication No. 1020060107268

It is an object of the present invention to provide a method and an apparatus for rendering a vector font considering a subpixel pattern that improves the rendering quality of a font by calculating pixel values according to a subpixel pattern and a thin line of a display device.

Another object of the present invention is to provide a method and apparatus for rendering a vector font considering sub-pixel patterns that can minimize the use of the conventional anti-aliasing method and thereby increase the efficiency of software or hardware.

According to an aspect of the present invention, there is provided a method of rendering a vector font considering a pattern of subpixels according to the present invention includes the steps of receiving a pattern of a subpixel of a display device from a user and a size of a font and a font; Rendering the font entered by the user in a predetermined size; Determining neighboring pixel groups for each pixel group having a predetermined size in the rendered font image to determine whether or not the pixel group is drawn; And calculating a pixel value by considering a subpixel pattern and assigning an output pixel value to a pixel group that is a thinner one among the pixel groups, and for a pixel group that is not a pixel group that is a thinner among the pixel groups, And calculating an average of the pixels to assign an output pixel value.

The present invention has an effect of improving font rendering quality by calculating pixel values according to a pattern and a thin line of subpixels of a display device.

In addition, the present invention minimizes the use of the conventional anti-aliasing method, thereby increasing the efficiency of software and hardware.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a vector font rendering apparatus considering a pattern of subpixels according to a preferred embodiment of the present invention; FIG.
FIG. 2 is a flowchart of a method of rendering a vector font considering a sub-pixel pattern according to a preferred embodiment of the present invention.
3 is a diagram illustrating a pattern of subpixels in a display device;
4 is a view illustrating a rendering process of a vector font considering a pattern of subpixels according to a preferred embodiment of the present invention.

The present invention improves the rendering quality of the font by minimizing the use of the anti-aliasing method by increasing the efficiency of the software or hardware by calculating the pixel value according to the pattern and the thin line of the sub-pixel of the display device.

An apparatus and method for rendering a vector font considering sub-pixel patterns according to a preferred embodiment of the present invention will be described in detail with reference to the drawings.

&Lt; Rendering device of vector font considering subpixel pattern >

A configuration of a vector font rendering apparatus considering a pattern of subpixels according to a preferred embodiment of the present invention will be described with reference to FIG.

The rendering apparatus includes a processing device 100, a memory 102, a display device 104, and a user interface 106. [

The processing unit 100 performs operations for a user application program and various font rendering systems, and performs operations for a vector font renderer considering a subpixel pattern according to a preferred embodiment of the present invention. Here, the vector font renderer may be implemented by software or hardware.

The memory 102 stores various information including a processing program of the processing apparatus 100, and particularly stores information for a vector font renderer that considers subpixel patterns according to a preferred embodiment of the present invention.

The display device 104 displays information according to the control of the processing device 100.

The user interface 106 receives various information from a user and provides the information to the processing device 100.

A vector font rendering method considering a subpixel pattern applicable to the rendering apparatus will be described with reference to the flowchart of FIG.

The user inputs the pattern, font, and font size of the subpixel of the display device 104 desired by the user through the user interface 106 (operation 200).

The patterns of the subpixels indicate in what order and direction the red (R) subpixels constituting one pixel are arranged in the display device as illustrated in FIG. The pattern of the subpixel illustrated in FIG. 3A is a horizontal RGB, a horizontal BGR in the case of (B), a vertical RGB in the case of (C), and a vertical BGR in the case of (D).

The processing device 100 renders the character requested by the user in the size of three times by three times the size (step 202), examines the surrounding 9 * 9 pixels for each of the 3 * 3 pixel groups belonging to the rendered image, (Step 206). To be more specific, the processing apparatus 100 is filled with a group of peripheral pixels of 3 * 3 pixel groups to be rendered, that is, 3 * 3 pixel groups on the left, upper, lower and right sides of 3 * 3 pixel groups If there is no case, it is judged as a fine stroke.

If the 3 * 3 pixel group among the 3 * 3 pixel groups is a thin line, the processing apparatus 100 mixes 3 * 3 pixel values considering the subpixel pattern of red, green, and blue Step), which is shown in Equation (1).

P1, P4 and P7 are values of pixels corresponding to green (G), and P2, P5 and P6 are values of pixels corresponding to red (R) in the 3 * 3 pixel group, , P8 is the value of the pixel corresponding to blue (B), and Or, Og, and Ob are the mixed cyan 3 * 3 pixel red cyan values. This is illustrated in FIG. Also, 4, 2, 21, 12, etc. written in the above Equation 1 are variables, and other values may be selected to further improve the quality of the rendering. According to a preferred embodiment of the present invention, different values may be selected depending on the pattern of the subpixel.

Alternatively, if no 3 * 3 pixel group among the 3 * 3 pixel groups is a fine stroke, the processing unit 100 calculates a 3 * 3 pixel value as an average of the pixel values of the 3 * 3 pixel group ( Step 210).

The processing apparatus 100 allocates the 3 * 3 pixel value calculated in step 208 or 210 as an output pixel value (step 212).

If the allocation of the output pixel values is made for all 3 * 3 pixel groups (step 214), rendering according to the present invention is completed.

The program according to the vector font rendering method considering the pattern of subpixels according to the present invention can be stored in a storage medium, which is obvious to a person skilled in the art by the present invention.

In addition, a program according to the method of rendering a vector font in consideration of the pattern of subpixels according to the present invention may be implemented or used as a device implemented with a logic circuit, which is obvious to a person skilled in the art by the present invention.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, And variations are possible.

Accordingly, it is to be understood that the scope of the present invention is to be determined solely by the appended claims, and all equivalent or equivalent variations thereof are included in the scope of the present invention.

100: Processing device
102: Memory
104: Display device
106: User interface

Claims

A method of rendering a vector font in consideration of a pattern of subpixels,
Receiving a pattern of a sub-pixel of a display device, a font, and a font size from a user;
Rendering the font entered by the user in a predetermined size;
Determining neighboring pixel groups for each pixel group having a predetermined size in the rendered font image to determine whether or not the pixel group is drawn;
For a pixel group that is a thin stroke among the pixel groups, a pixel value is calculated in consideration of a sub-pixel pattern, an output pixel value is assigned,
And calculating an average of pixels belonging to a pixel group and assigning an output pixel value to a pixel group that is not a pixel group that is a thin one among the pixel groups. Way.

The method according to claim 1,
Wherein the pattern of the subpixels is a sequence and directions of red, green, and blue subpixels constituting pixels of the display device.

The method according to claim 1,
Wherein the predetermined size is rendered by a user in a size of three times the size of a character requested by the user.

The method of claim 3,
Wherein the step of determining whether or not the fine stroke is to be performed is to determine whether a stroke is a small stroke by inspecting 9 * 9 pixels around each 3 * 3 pixel group belonging to the rendered image.

The method according to claim 1,
And calculating a pixel value for a pixel group that is a thin one among the pixel groups, according to Equation (2).
Equation 2

P1, P4 and P7 are the values of pixels corresponding to green (G), and P2, P5 and P8 are the values of the pixels corresponding to red (R) in the pixel group, (B), and Or, Og, and Ob are the cyan values of the blended pixels, and A to H are the variables.

The method according to claim 1,
The pixel group,
And determining whether or not the neighboring pixel groups are all filled in the sub-pixel group.

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