JPH01306972A - Picture processor - Google Patents

Abstract

PURPOSE:To display an original in which a binary picture of characters, line drawings, etc., and half-tone picture coexist in a mixed state in an excellent state by setting a desired area in the displayed original by means of an area setting means and displaying the set area after changing the thinning state of the picture of the area by means of a changing means. CONSTITUTION:At the time of displaying an original in which a document and photographic picture coexists in a mixed state by reading the original in the photograph displaying mode, an operator designates areas 48 and 49, because he wants to set the character displaying mode to the document area. Upon detecting his operation, a CPU 1 calculates the position and size of the area corresponding to the area 48 in a memory 30 for picture and develops the picture in the corresponding area in the memory 30 in the area corresponding to the area 48 in a VRAM 25 after thinning the picture at every other picture element by means of a 1/N reduction circuit 31. Then the CPU 1 continuously performs similar operations to the area 49. Therefore, even when an original in which a binary picture and half-tone picture coexist in a mixed state is inputted, each picture can be displayed in the optimum state.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an image processing device, and more particularly to an image processing device that displays manually generated images. ' [Prior Art] Conventionally, there are devices that optically read a document and output the read image on a display screen or to a printing device.

Normally, the loaded image is displayed on the display screen as is, but as high definition is desired these days, the reading accuracy of image readers continues to increase, and the display capacity of display devices is currently unable to keep up with this. be.

Therefore, one possible solution is to perform thinning processing when loading the read image into the display memory (VR'AM).

[Problems to be Solved by the Invention] By the way, document images to be read include binary images such as characters and line drawings that require edge enhancement, and halftone images such as photographs that have shading.

However, no matter which of these two images is used for reading the image, one image must be sacrificed on the display screen.

The present invention has been made in view of such prior art, and it is an object of the present invention to provide an image processing bag that can display mixed images of binary images such as text and line drawings and halftone images in good condition.

[Means for Solving the Problem] In order to solve this problem, the present invention includes the following configuration.

That is, a display memory, an input means for inputting image data from the outside, an image memory for rasterizing the input image data, and an image data rasterizing the image data rasterized in the image memory in units of pixel blocks or pixels of a predetermined size. A display means for thinning the image in a thinning form and transferring the data to the display memory for display; an area setting means for setting a desired area in the displayed image; and a changing means for changing the thinning form for the set area. .

[Operations] In the configuration of the present invention, a desired area in the image displayed by the display unit is set by the area setting unit, and the thinning form of the image within the set area is changed by the changing unit and displayed. It is something to do.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Description of Configuration (FIGS. 1 and 2)> FIG. 1 is a block schematic diagram of an image processing apparatus in an embodiment.

In the figure, reference numeral 1 denotes a control unit, which executes processing based on image processing. 2 is a display device that displays edited images; 3 is an optical disk device that can store a plurality of image information;
Reference numeral 4 denotes a keyboard for inputting various information related to editing processing, and a pointing device (for example, a mouse) 5 for specifying an arbitrary position on the display screen for editing characters is connected. 6 is a microreader that optically reads the microfilm, and 7 is an image scanner that reads the original image. Reference numeral 8 denotes a printer, and the printer 8 in this embodiment is capable of high-definition printing, such as a laser beam printer.

Next, the details inside the control section 1 are shown in FIG. 2 and will be explained below.

In the figure, 21 is a CPU that controls the entire control section 1, and controls various units connected to the bus 22 according to the program (processing procedure based on the flowchart in FIG. 5) stored in the ROM 29a in the main memory 29. Control. 23
1 is a rask operation unit that controls the rotation, movement, etc. of the image displayed on the display device 2. In addition, 24 is a memory management unit (M
MU), and 25 is a VRAM. This VRAM2
5, the image data to be output to the display device 2 is expanded.
One bit is assigned to each display pixel. 2
6 is the micro reader 6 and image reader 7 explained earlier.
27 is also an interface circuit for exchanging data with the printer 8 and the keyboard 4. This is an interface circuit with the optical disk device 3, display device, etc.

Reference numeral 28 denotes a companding circuit for compressing or expanding image data, which compresses the image data when it is stored in the optical disk device 3 and decompresses it when it is read out. Reference numeral 29 denotes a main memory, in which an internal ROM 29a stores a program for the operation processing procedure of the CPU 21 described above, and a RAM 29b is used as its work area. Reference numeral 30 denotes an image memory to which one bit is allocated per pixel, and has a capacity corresponding to that for printing. usually,
Currently, the resolution on a display screen is lower than that on a printout. Therefore, actual image information is developed in this image memory 30, and pixel data every few pixels is developed from the image memory 30 in the VRAM 25. This makes it possible to display the entire image in the image memory 30 in a pseudo manner on the display screen. In order to make the following description more clear, in the embodiment, the size of the VRAM 25 (display capacity of the display screen) will be described as having half the size of the image memory 30 in both the vertical and horizontal directions. In addition, in the process described later, when specifying a detailed location in the image displayed on the display screen using the pointing device 5, data in the image memory 30 corresponding to the vicinity is expanded as is in the VRAM, thereby effectively It is possible to enlarge and display the image. Note that these enlargement/reduction processes are performed by the 1/N reduction circuit 31.

<Explanation of the outline of image processing (FIGS. 3 and 4)> The outline of the image processing in the above-described configuration will be described below with reference to FIGS. 3 and 4.

In the embodiment, a document image is first read by the image reader 7. At this time, the user specifies from the keyboard 4 whether the original image is to be read as a photographic image (hereinafter simply referred to as photographic mode) or as a text and line drawing image (hereinafter simply referred to as character mode).

Although the explanation may be complicated, inside the image reader 7 there is a device A that converts the read pixel density level signal into digital data.
/D converter, which allows for example 8 pixels per pixel.
The following explanation assumes that multi-value data of bits (0 to 255 gradations) is output.

Now, when the document is read, if the character mode is set, the following processing is performed and the document is developed (displayed) in the VRAM 25.

First, since the 8-bit pixel data output from the image reader 7 cannot be loaded into the image memory 30 as it is, the data is converted to a predetermined threshold value, for example 128 degrees.
When the value is higher than the value, the value is converted to ``1'', and when the value is lower than the value, the value is converted to ``0''.The binarization process is performed and the result is expanded in the image memory 3o.

After this, the image memory 30 is
Every other pixel in the vertical and horizontal directions is read from the image data developed in the image data, and is developed (displayed) in the VRAM 25. below,
This processing corresponds to character mode and is called character display mode.

On the other hand, when reading an original image in photo mode,
Perform the following processing (the following processing is called photo display mode).

First, four lines of pixel data output from the image reader 7 are temporarily stored in the RAM 29b within the main memory 29. Then, using known dither processing, dither processing is performed in units of 4×4 pixel blocks, and the results are developed in the image memory 30. Thereafter, similar processing is performed on other pixel blocks in the RAM 29b, and this processing is repeated until image data for one document image is output from the image reader 7.

After the dithered image is developed in the image memory 30 in this way, this image is reduced and transferred to the VRAM 25. At this time, if the same processing as in the previous character display mode is applied, an image that looks strange will be displayed, so in this embodiment, the pixel block is thinned out in units of pixel blocks before being transferred to the VRAM 25.

That is, first, a 4×4 dithered pixel block is transferred from the image memory 30 to the VRAM 25 as it is. Then, the next pixel block is not transferred, but the next pixel block is transferred.

By doing so, the photographic image can be displayed as a pseudo halftone image on the display screen.

In the above example, the image reader 7 may be used as the target, or the microreader 6 may be used as the target.

In any case, when the image is displayed on the display screen in photo display mode or text display mode, the operator can specify a desired area and display that area as a halftone image. , or display as text and line drawing images.

An example of this processing is shown in FIGS. 3 and 4(a) below.

This will be explained in (b).

Assume that an image 41 (which may be in text display mode or photo display mode) as shown in FIG. 3 is being displayed on the display device 2.

The operator looks at this display screen, specifies a desired area, and changes the display mode within that area by specifying one of the icons 42 and 43 located at the bottom of the screen.

In the embodiment, the pointing device 5 is used for specifying the area and changing the display mode.

As shown in FIG. 4(a), area designation is carried out by moving a rectangular area 47 surrounding an image to be specified using two points, that is, points 45 and 44 in the illustrated case, using a graphic that is linked to the pointing device 5. The settings are made while moving the cursor 44. Thereafter, by moving the graphic cursor 44 and specifying which icons 42 and 43 to be edited, the display mode of the image within that area 47 is changed. However, if the display mode of the image displayed before specifying the area is the same as the display mode specified after specifying the area, nothing is done.

Assume that the image 41 shown in FIG. 3 is a document image in which a document (broken lines in the figure correspond to characters) and a photo image are mixed, which is read and displayed in the photo display mode, as shown in the figure. . At this time, the operator wants to set the document area to character display mode, so naturally, the
Area 48 and area 49 are designated as shown in b). Actually, after specifying the area 48, the icon 42 is specified with the graphic cursor 44, and then the area 49 is specified, and the same operation is performed.

When the CPUI detects the above operation, it first selects area 4.
The position and size of the corresponding area in the image memory 30 for 8 are calculated, and the image in the corresponding area in the image memory 30 is thinned out every other pixel by the 17N reduction circuit 31 and stored on the VRAM 25. The image is expanded to an area corresponding to area 48.

After this, similar processing is applied to area 49 as well.

On the other hand, when the display mode is photo display mode and character display mode is specified for the specified area, the position and size of the area with respect to the image memory 30 are similarly calculated, and the image within that area is The data is thinned out in units of ×4 pixel blocks and expanded and displayed in the VRAM 25.

<Explanation of Processing Procedure (FIG. 5)> To summarize the above explanation, the control processing procedure of the CPU 2 becomes the flowchart shown in FIG. 5.

First, in step S1, a document image reading mode is set, and in the next step S2, the image is read based on the set speed and the image is displayed.

After this, it is determined whether or not to specify a display mode change area. If there is an area to be changed, the process proceeds to step S4, where a rectangular area to be changed is created. If the change area is not designated, the process proceeds to step S5, where all the displayed images are recognized as the change area.

Then, in step S6, the display mode of the changed area is set. In the next step S7, it is determined whether the current display mode in the change area and the set display mode match. If they match, there is no need to change, and the process returns to step S3. In addition, if they do not match, step S
Proceeding to step 8, the position and size of the set area in the image memory 30 are calculated. Then, in the next step S9, only the calculated area in the image memory 30 is sent to the 1/N reduction circuit, reduced (thinned) according to the specified display mode, and transferred to the corresponding area in the VRAM 25. The results are then displayed in step S10.

As explained above, according to this embodiment, even if an image containing a mixture of text and line drawing images and photographic images is read, it is possible to provide a display format corresponding to each image while looking at the display screen. , it is possible to display both and subsequent images.

In the embodiment, the image memory 30 and the VRAM 25 each allocate one bit to each pixel to express a photographic image, so that the memory capacity is small, and costs can be reduced.

Furthermore, although the embodiment deals with monochrome images, it may be applied to color images as well.

Further, in the embodiment, the display mode change area has been described as a rectangular area, but it is not limited to this. for example,
This is because it may be set so that the free curve is closed.

Furthermore, image input is not done using an image reader, etc.
A similar effect can be achieved by inputting information from a host computer, external storage device, etc.).

[Effects of the Invention] As explained above, according to the present invention, even if an image containing a mixture of binary images and halftone images is input, each image can be displayed in the optimal display format. Become.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of this embodiment, Fig. 2 is a block diagram explaining the control section of Fig. 1, Fig. 3 is a diagram showing a state in which image data is displayed, and Fig. 4 (
a) and (b) are diagrams for explaining area setting, and FIG. 5 is a flowchart showing the control processing procedure of the CPU in this embodiment. In the figure, 1...control unit, 2...display device, 3...optical disk device, 4...keyboard, 5...pointing device, 6...microreader, 7...image Reader, 8...Printer, 25...vRAM
, 26° 27... Interface, 28... Companding circuit, 29... Main memory, 29 a. ROM, 29
b-RAM, 30...image memory, 31...I
/N reduction circuit. Patent Applicant Canon Co., Ltd. Agent Patent Attorney Yasunori Otsuka (and 1 other person) Figure 5

Claims (1)

[Claims] A display memory, an input means for inputting image data from the outside, an image memory for rasterizing the input image data, and an image memory for rasterizing the image data rasterized in the image memory into pixel blocks of a predetermined size or a display means for thinning out pixels in a unit thinning mode and transferring the pixel to the display memory for display; an area setting means for setting a desired area in the displayed image; and changing the thinning mode for the set area. An image processing device comprising a changing means.