JP2703223B2 - Color image processing equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a color image processing method. 2. Description of the Related Art Conventionally, output devices for outputting image data include a monitor for temporarily displaying an image and a printer for permanently printing an image. Regarding the resolution of such a device, it is common that the resolution of the printer is considerably higher than the resolution of the monitor. Therefore, when editing image data on a monitor and printing the edited image with the highest possible image quality, the image data is compressed and stored on a storage medium to reduce the memory capacity, and the image data is stored on the monitor. When outputting, the stored compressed image data is decompressed, thinned out, converted to the display resolution of the monitor and output, and image editing conditions are set on the monitor. On the other hand, when outputting image data to a printer, the compressed image data stored in the storage medium is decompressed, converted to the recording resolution of the printer, image edited according to the image editing conditions, and printed out. I was [Problems to be Solved by the Invention] However, in the above conventional example, in order to output image data on a monitor when setting image editing conditions, the image data stored in the storage medium is expanded and the display resolution of the monitor is reduced. It is necessary to perform a plurality of processes such as thinning out at the same time, and there is a problem that a considerable amount of time is required until displaying on a monitor. This problem becomes more serious when the processing data is color image data. Further, in the above conventional example, when outputting image data to the monitor, since the compressed image data is decompressed and then thinned out, there is a lot of data that is not considered in the display, and the image editing conditions are changed. It was not good as a display image for setting. The present invention has been made in view of the above conventional example, it is possible to reduce the capacity of a medium for storing data, has good color reproducibility of a monitor image at the time of editing, is capable of high-speed monitor display, Another object of the present invention is to provide a color image processing method capable of printing and outputting a high-quality image. [Means for Solving the Problems] To achieve the above object, the color image processing method of the present invention comprises the following steps. That is, the color image data of the first resolution is compressed in consideration of the plurality of pixels for each unit block composed of a plurality of pixels, and is data of a second resolution which is data lower than the first resolution. A generating step of generating block-coded compressed data including representative color data representing a plurality of pixels; a storing step of storing the block-coded compressed data generated by the generating step in a storage medium; and setting image editing conditions. A setting step, a display step of displaying the edited representative color data based on the image editing conditions set in the setting step, and editing and expansion based on the image editing conditions set in the setting step. And a processing step of printing out the obtained first resolution color image data. Embodiment An embodiment according to the present invention will be described below in detail with reference to the accompanying drawings. In this embodiment, a case where the present invention is applied to a color image processing apparatus will be described. [Explanation of Configuration Diagram (FIG. 1)] FIG. 1 is a block configuration diagram of the image processing apparatus according to the present embodiment. In the figure, reference numeral 101 denotes a control processing device for controlling the entire apparatus, which performs processing according to a program stored in 102. 103 is a keyboard, 104 is a mouse which is one of pointing devices, and these are control processing devices.
Connected to 101. Reference numeral 105 denotes an image reading apparatus for reading an image, and the read image data is compression-encoded by the compression encoder 106 (this compression-encoded image data is simply referred to as encoded data hereinafter). ).
The details of the compression encoder 106 will be described later. Reference numeral 108 denotes a decompression decoder that decodes encoded data. The decoded image data forms a permanent visible image (print output image) with the printing device 107. Reference numerals 109 and 110 denote image memories for storing encoded data formed by the compression encoder 106 via a system bus 118. Reference numeral 112 denotes a display device 1 by combining arbitrary areas in the image memories 109 and 110.
13 is a synthesizing unit that outputs the image data to the area 13, and the area to be synthesized is determined by the flag data stored in the image flag memory 111. [Explanation of Compression Encoding (FIG. 4)] Hereinafter, the compression encoder 106 will be described with reference to FIG. In the figure, reference numeral 400 denotes a pixel block read by the image reading device 105, which is 4 × 4 pixels in this embodiment. Each pixel has 256 gradations (8 bits) for each of the color components R (red), G (green), and B (blue). Therefore, the total number of pixel blocks 400 input via the bus 451 is 384.
It consists of data of bits (= 8 × 16 × 3). The pixel block 400 sequentially output from the image reading device 105 is sent to the representative color extraction unit 401 in the compression encoder 106 via the bus 4.
The color information which is input through 51 and is best represented when the pixel block 400 is viewed as a whole is extracted. In the present embodiment, the description is made assuming that the average value of the gradation for each color component (R, G, B) of each pixel is taken, but the present invention is not limited to this. For example, it may be determined from the color distribution (standard deviation) of each pixel. In any case, the representative color of the pixel block 400 is determined and output as the representative color information 404a of the encoded data 404 via the bus 453. When the compression encoder 401 determines a representative color, a value (threshold) for each color component is determined.
Is output to the bus 452. The pixel block 400 is also input to the buffer memory 402 once. Note that the buffer memory 402 can store a plurality of pixel blocks. When the representative color is extracted by the representative color extracting unit 401 and the threshold is input to the binarizer 403 via the bus 452, the pixel block corresponding to the threshold is also input from the buffer memory 402 to the binarizer 403. And binarized. 4 × 4 for each binarized component
Are output as detailed information 404b of the encoded data 404. Further, the pixel block 4 stored in the buffer memory 402
00 is input to the variance value calculation unit 405 via the bus 455, and the variance value σ _R , based on the input pixel block 400 and the average value of each color component output on the bus 452 from the representative color extraction unit 401, σ _G and σ _B are calculated. For example, the variance σ _R of “R (red)” is as follows. In the equation, n is the number of pixels (16), and _AR is _R for each pixel.
(Red) the average value of the components, R _i denotes a gradation of each pixel. The same calculation can be performed for the other G (green) and B (blue). The variances σ _R , σ _G , σ _{B for} each color component obtained in this way are output as the variance information 404c of the encoded data 404 via the bus 456, and the representative color information 404a and the detailed information 404b described above are output. With encoded data 40
4 will be composed. At this time, since the detailed information 404b is binary information of each color component of the pixel block 400, a total of 48 bits (=
16 × 3), and the variance value information 404c is represented by 8 bits for each color component.
4 is representative color information 404a (8 × 3 bits) and detailed information 404b (1
6 × 3) and the shared information 404c (8 × 3 bits), for a total of 96 bits, and the size of the 384 bits of the pixel block 400 is compressed to / 4. [Explanation of Operation of Apparatus (FIGS. 2 and 3)] The encoded data 404 formed by the above processing is displayed on the display device in the same manner as ordinary image data. That is, when displaying on the display device, only the representative color information is displayed as image data. Accordingly, the number of display dots on the display screen can be set to 1/16 of the number of pixels read by the image reading device 105. The following description is an example applied to a case where image processing is performed on data that has been compressed and encoded in this manner. Now, the compressed and encoded image A shown in FIG.
(Hereinafter, simply referred to as image A) is stored in the image memory 10, and the compressed and encoded image B (hereinafter, simply referred to as image B) shown in FIG. Shall be Then, for these images A and B, the second
The process up to forming the compressed and encoded image C (hereinafter simply referred to as image C) shown in FIG. The operator inputs an appropriate command using the keyboard 103 or the mouse 104, and rotates and reduces only the image B in the image memory 109. In the next stage, the image B thus processed
Bit map information representing the contour information for the image is converted to mask information (information of "1" or "0"), and the image flag memory
Stored in 111. Here, the outline information of the image B is formed by scanning the image memory 109 to form the outline flag data in the image memory 111. However, for example, the mouse 104 is driven to trace the outline. May be used to specify the boundary. Now, as described above, each image and mask information are stored in the memory 109.
After being stored in .about.111, the composite display of the images A and B is started. FIG. 3 is a diagram showing the internal configuration of the synthesizing unit 112. In the figure, 301 and 304 are signal selectors for selecting one of the input signals, and the signal selector 301 is based on mask information (sent to the signal line 114) of the image flag memory 111. One of the images A and B is selected. Reference numeral 302 denotes a signal adder for adding the gradations of the images A and B. The added data is halved (averaged) by the 1/2 circuit 303. The output of the 1/2 circuit is connected to one input side of the signal selector 304. Therefore, for example, when the level of the signal line 351 is “0”, the image data selected by the mask information in the image flag memory 111 is output to the display device via the signal line 117. The display image at this time is an image C on which images A and B are superimposed as shown in FIG. 2 (c). When the level of the signal line 351 is “1”, the images A and B
Will be output to the signal line 154, and the images A and B will be transmitted and synthesized and displayed. Note that, even with the above configuration, the contour may be conspicuous when combining images. In such a case, it is achieved by controlling the signal line 351 so that the average value image is selected at the contour portion. In other words, the image A,
The ratio of the composite display of B can be controlled in three stages of 100: 0 → 50: 50 → 0: 100%. When the image desired by the operator is displayed,
Based on the synthesized image C, the image memory 10
The image B in the image 9 and the image A in the image memory 110 are combined and stored in the image memory 110. At this time, not only the representative color information 404a in each encoded data but also the detailed information 404b and the
4c is also processed as a synthesis target. As a result, the image C is formed in the image memory 110. [Explanation of Decompression Decoding (FIG. 5)] When the image C is finally printed out, the encoded data of the image C stored in the image memory 110 is sequentially transferred to the decompression decoder 108. And decrypt. The decompression decoder 108 inputs the encoded data 404
Is decoded into pixel blocks having 4.times.4 gradations from the representative color information 404a, detailed information 404b, and dispersion information 404c. Actually, for a pixel that has been binarized to “1” for each color component in the detailed information 404b, the average gradient (A _R , A _G , A _B ) plus the variance σ _R , σ _G , σ _B ) of each component.
In addition, decoding processing is performed by subtracting the variance value from the average gradient for a pixel which has been binarized to “0”. For example, for a color component "R (red)", is Natsuta pixel X _R binarized to _{"1", X R = A} R + σ R ... 2 binarized to Natsuta pixel to "0" X _R is given by the _{X R = a R -σ R ...} . FIG. 5 shows a simple transition of the binarization process and the decoding process for the color component "R". In the figure, reference numeral 50 denotes a pixel block of the color component “R” read by the image reading device 105. The numerical value in each pixel indicates the gradation value of the color component “R”. Reference numeral 51 denotes a binarization block obtained by binarizing the pixels in the pixel block 50 with the average value of the gradation (A _R ≒ 53 when calculated). The average value is calculated by the representative color extracting unit 401 as described above. Further, the variance of each color component is calculated by the variance value calculation unit 405 using the variance calculation formula described above from the calculated average value of each color component and the pixel block. In this case (FIG. 5), the variance σ _R ≒ 19. Reference numeral 52 denotes a decoded pixel block when the binarization block 51 is decoded. Now, when decoding this binarized block into a decoded pixel block 52, the binary block 51
Tone value of "1" and summer in which pixel in the is _{"72 (= A R + σ} R
= 53 + 19) ”and the pixel that is“ 0 ”is“ 34 ”.
(= A _R -σ _R ) ", and a decoded pixel block 52 similar to the pixel block 50 is formed. By the way, at the time of normal printing, it is converted to YMC (yellow, magenta, cyan) or the like and output to the printing device 107. However, since this process employs a conventional conversion process, a description thereof will be omitted in the present embodiment [Explanation of another combined display (FIG. 6)] In the above embodiment, combined display is performed. At the time, the case where the combined display of the image A and the image B is combined and displayed at the ratio of three steps has been described, but a further developed example will be described with reference to Fig. 6. In the figure, reference numeral 111a denotes an image flag memory. This time, it is assumed that each of the image memories 109 and 110 is composed of 4 bits per pixel, and the ratio of the composite display of the image A and the image B is multi-step (for 4 bits). 16 steps) Also, 60 and 61 increase the gradation value of the image data output on the buses 115 and 116 by a factor of 0.0 to 1.0 based on the 4-bit value sent from the image flag memory 111a via the bus 63. Is a multiplier that multiplies the values in 16 steps in total.
This is an adder for adding the signal from 1 and outputs the added result on a signal line 117 to the display device 113. Now, suppose that (F) ₁₆ , that is, all four bits are at a high level on the bus 63. At this time, the multiplier 60 multiplies the gradation of the image data on the cross 115 by 1.0, that is, outputs it to the adder 62 as it is. On the other hand, since the data from the image flag memory to the multiplier 61 is inverted (that is, (0) ₁₆ ) and input, the gradation of the image data on the bus 116 is 0.0 times, that is, the output to the adder 62. Becomes “0”. The adder 62 simply adds the gradation of the input image data and outputs the result to the display device 113 via the signal line 117.In this case, only the image on the bus 15 is output to the display device 113. That is. As can be seen from the above description, the image flag memory 111a
Can be displayed in multiple stages of the composition ratio of the gradations of the image data output on the buses 115 and 116. For example, the gradation near the contour of two images to be combined can be displayed. By combining the images in multiple stages, the sense of incongruity of the contour portion, which is caused by combining the images, is eliminated. Further, it is possible to perform smooth image synthesis in which one image is switched to another image. [Explanation of Other Configuration Diagrams (FIG. 7)] FIG. 7 is a further development of the block configuration diagram of FIG. In the drawing, the difference from the configuration of FIG. 1 is that the image memories 109 and 110 and the image flag memory 111 are not directly connected to the system bus 118 but are provided through a processing unit 701. In the configuration of FIG. 1, it is difficult to access the memories 109 to 111 at the same time, and the processing by the control processing device 101 takes time. Therefore, here, the control processing device 101 is distributed and divided into a control device 702 and a processing device 701. According to this configuration, the efficiency is improved by parallelizing the access (read / write) to each memory, and the system bus 11
Since the use efficiency of 8 is reduced, the control unit 702 can perform other processing, and the processing speed of the entire system increases. As described above, according to this embodiment, data obtained by compressing color image data down to a fraction is displayed on a display screen, subjected to image processing, and output as a high-resolution image when printed. It becomes possible. Further, at the time of image editing, since only the representative color information is changed, the processing speed of the image processing is improved. Further, the composition ratio of the two images can be set in multiple stages, which makes it possible to eliminate a sense of discomfort at the outline of the image to be composed, and to smoothly switch from one image to the other image. Display enabled. Further, since the display image and the output image for printing etc. are not separated from each other, there is no need to perform double processing for each memory, and it is possible to configure the memory with a small amount of memory, and to reduce the cost. Become. In the present embodiment, a description has been given of the case where the combining ratio of the two images is multi-step. However, a logical operation such as a logical sum or a logical product may be performed on the two images. Further, the pixel block is not limited to the size of 4 × 4, but can be generally realized with n × m pixels. Further, for example, in the case of an apparatus for processing an image of only one color (for example, black), it can be easily realized by focusing on one of the color components constituting the color image described in the present embodiment. It is. [Effects of the Invention] As described above, according to the present invention, image data requiring two processes of display on a monitor and printout are compressed and stored, so that the capacity of the recording medium can be reduced. There is. In addition, since the representative color data included in the block coded compressed data is used as data for confirming the editing result according to the image editing conditions before printing, conventionally required compressed data is expanded, for example, the compressed data is expanded. It is not necessary to perform time-consuming processing such as thinning out data, and as a result, the load on the processing unit that executes the above-described processing that has been conventionally required can be reduced, and high-speed display can be performed. This effect is more remarkable when processing a color image as in the present invention than when processing a monochrome image. Furthermore, since representative color data obtained by compressing a unit block consisting of a plurality of pixels in consideration of the plurality of pixels is used as display data, the data amount is reduced, high-speed display is realized, and color reproducibility is achieved. , And color display can be performed. Furthermore, the first resolution color image data, which is a high resolution obtained after editing and decompression, is processed for printout based on the image editing conditions, so that a high quality color image can be printed. There is also an effect.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of an image processing apparatus according to this embodiment, FIGS. 2 (a) and 2 (b) show images to be combined, and FIG. FIG. 3 is an internal configuration diagram of the synthesizing unit shown in FIG. 1, FIG. 4 is an internal configuration diagram of the compression encoder shown in FIG. 1, and FIG. 5 is compression-encoded data. Fig. 6 is a diagram for explaining the process up to decompression decoding, Fig. 6 is a diagram for explaining another synthesizing unit, and Fig. 7 is a block diagram of another image processing apparatus according to the present embodiment. In the figure, 101 ... control processing device, 102 ... memory, 103 ...
Keyboard 104 104 Mouse 105 Image reading device 10
6 compression encoder, 107 printing device, 108 decompression decoder, 109, 110 image memory, 111, 111a image flag memory, 112, 112a synthesis unit, 113 display device, 1
14 to 117: Signal line, 118: System bus, 301, 304 ...
... Signal selector, 302 ... Signal adder, 303 ... 1/2 circuit, 4
00: Pixel block, 401: Representative color extractor, 402: Buffer memory, 403: Binarizer, 404: Encoded data, 404a: Representative color information, 404b: Detail information, 60, 61 …
.., Multiplier, 62, adder, 701, processing device, 702, control device.

   ────────────────────────────────────────────────── ─── Continuation of front page    (56) References JP-A-52-106625 (JP, A)                 JP-A-55-150662 (JP, A)                 JP-A-60-1967 (JP, A)                 JP-A-61-175863 (JP, A)                 JP-A-61-255164 (JP, A)                 JP-A-55-110484 (JP, A)                 JP-A-60-87596 (JP, A)                 JP-A-61-52074 (JP, A)

Claims (1)

(57) [Claims] Color image data of a first resolution is compressed in consideration of the plurality of pixels for each unit block composed of a plurality of pixels, and data of a second resolution which is data lower than the first resolution; Generating a block-encoded compressed data including representative color data representing the following: a storage step of storing the block-encoded compressed data generated by the generating step in a storage medium; and setting an image editing condition. A display step of displaying the edited representative color data based on the image editing conditions set in the setting step; and a display step of editing and expanding based on the image editing conditions set in the setting step. And a processing step of printing out color image data of the first resolution.