JP3774561B2 - Image processing apparatus and method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image processing apparatus and method, for example, an image processing apparatus and method for compressing and storing image data.
[0002]
[Prior art]
With the recent development of image processing technology, for example, an image processing apparatus that realizes the functions of a plurality of devices such as a copying machine, a printer, and a facsimile machine with a single device has become widespread as a so-called digital multifunction peripheral. In a conventional multifunction device, a plurality of image data is input and temporarily stored in its own memory, thereby classifying the plurality of image data and controlling the output order; A device that realizes an electronic sort function has been proposed.
[0003]
In such a high-function image processing apparatus, the amount of image data stored in the apparatus tends to increase, and color image data is often handled. Therefore, in order to effectively use memory resources in the apparatus, it is common to store image data after compression.
[0004]
Also known is a method of improving the compression rate by converting the format of the image data and then compressing it when storing a large amount of data such as a color image in the memory in the image processing apparatus. ing.
[0005]
[Problems to be solved by the invention]
However, when the conventional image processing apparatus performs format conversion on the image data before compression, a high compression rate may not be expected depending on the image.
[0006]
For example, in the case of image data composed of CMYK color components, if the configuration of each color component is very similar, if the image data of each color component is converted to be continuous for each pixel, four consecutive data Since a data format that frequently appears is generated, a high compression rate can be expected.
[0007]
However, the configuration of CMYK color components is not similar to each other, and if there is little data change over the entire image within each color component, the CMYK image data is continued for each pixel as described above. However, since four consecutive data do not appear frequently, a high compression rate cannot be expected. Rather, when compression is performed for each color component, a high compression ratio can be expected because there is less data change in each color component.
[0008]
As described above, the conventional image processing apparatus does not take into account the characteristics of each color component of the image data to be compressed, so it is flexible to generate a data format for obtaining a high compression ratio. However, depending on the image, the compression rate was lowered by format conversion.
[0009]
The present invention has been made in order to solve the above-described problems, and by converting the data into an appropriate data format in consideration of the characteristics of the color components constituting the image data, a high compression rate is obtained. An object of the present invention is to provide an image processing apparatus and method for obtaining the above.
[0010]
[Means for Solving the Problems]
As a means for achieving the above object, an image processing apparatus of the present invention comprises the following arrangement.
[0011]
That is, input means for inputting image data, extraction means for extracting features of the image data, conversion means for converting the image data into a format corresponding to the features extracted by the extraction means, and the conversion means possess a compression means for compressing the converted image data, and a holding means for holding the image data compressed by the compression means, the extracting means extracts the characteristics of the color components constituting the image data The converting unit converts the image data into a frame sequential format in which each color component is connected for each screen, and the extracting unit has a change amount for each color component in the entire image data smaller than a predetermined value. Is extracted as a feature, the conversion means converts the image data into the frame sequential format .
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment according to the present invention will be described in detail with reference to the drawings.
[0013]
<First Embodiment>
Apparatus Configuration FIG. 1 is a block diagram showing the configuration of the image processing system in this embodiment. In the figure, 1 is a scanner circuit that captures an image, 2 is a printer device that prints and outputs an image, 3 is a facsimile circuit that can send and receive images, 4 is a page created by a host 6 and transmitted via an interface circuit 5 A PDL circuit that develops description language (PDL) data into a bitmap image. The interface circuit 5 performs bidirectional communication of image data with the host 6. Reference numeral 7 denotes an input / output control circuit which controls writing and reading with the storage device 10 such as an MO drive or a hard disk via the buffer memory circuit 8 and the image conversion circuit 9. Reference numeral 11 denotes a determination circuit for determining the presence or absence of a specific image. Reference numeral 12 denotes a system control circuit composed of a CPU or the like that controls the entire image processing system, and performs overall control according to a program stored in the ROM 13. Reference numeral 14 denotes an MMI (man machine interface) circuit such as an operation unit for inputting various settings related to the image processing system by the user.
Outline of Input / Output Operation Hereinafter, an input / output operation of image data in the image processing system of the present embodiment having the above configuration will be described.
[0014]
First, image data input processing will be described.
[0015]
When an image reading instruction is given to the scanner circuit 1 under the control of the system control circuit 12, the scanner circuit 1 reads the image as digital image data. The read image data is stored in the buffer memory circuit 8 under the control of the input / output control circuit 7.
[0016]
On the other hand, the read image data is also supplied to the determination circuit 11 via the input / output control circuit 7. The determination circuit 11 extracts feature data from the image data, compares it with feature data of a specific image held in advance, and determines whether the image is a specific image based on the similarity. Then, the system control circuit 12 instructs the input / output control circuit 7 as follows based on the determination result. That is, if the image data is not determined to be a specific image, the image data is read from the buffer memory circuit 8 and supplied to the image conversion circuit 9 for compression processing and the like, and then stored in the storage device 10. If it is determined that the image data is a specific image, the subsequent processing is interrupted so that the image data in the buffer memory circuit 8 is not stored in the storage device 10 or is read from the buffer memory circuit 8. The image data is corrected, for example, by adding a specific pattern held in advance, and then stored in the storage device 10 via the image conversion circuit 9.
[0017]
If there are a plurality of document images, for example, a document placement sensor of an automatic document feeder provided in the scanner circuit 1 determines whether there is a document image to be read. The operation described above is repeated. At this time, a plurality of image data is stored in the storage device 10, but address management of each image data is performed by the system control circuit 12.
[0018]
Next, image data output processing in the image processing system will be described.
[0019]
The system control circuit 12 reads the image data stored in the storage device 10 by instructing the input / output control circuit 7, supplies the image data to the image conversion circuit 9, performs decompression processing, and then stores it in the buffer memory circuit 8. . Thereafter, the image data read from the buffer memory circuit 8 is supplied to the printer device 2 and printed out. If there are a plurality of image data, the above-described operation is repeated and printed out.
[0020]
Here, when only a part of the image data read from the storage device 10 is printed out, the processing is completed by the above operation. When a plurality of copies are printed out, the image data stored in the storage device 10 is stored. For example, when the rotation sort is designated by the MMI circuit 14, it is printed out after appropriately performing the rotation process. Note that the rotation sort means that, for example, when a plurality of copies are overlaid and printed out, for example, rotation discharge is alternately performed for each copy in order to make it possible to easily determine a break in the number of copies. In the present embodiment, when execution of rotation sort is designated by the MMI circuit 14, the system control circuit 12 controls the input / output control circuit 7 to perform rotation processing.
[0021]
The above operation is repeated until the final number of copies is printed out.
[0022]
By the way, in this embodiment, when it is determined by the determination circuit 11 that the image data being processed is a specific image, the storage of the image data in the storage device 10 is limited. You may memorize | store in the memory | storage device 10 as incidental information. This supplementary information can be used, for example, to notify the user via the MMI circuit 14 that the image data has been restricted.
[0023]
In the above description, the example in which the image data is read according to the stored order has been described. However, the present embodiment is not limited to this example. For example, the image data may be output in a different order from the input time. For example, when a pamphlet is created by saddle stitching printing paper, it is necessary to appropriately perform print output on the front and back surfaces of the printing paper.
Format Conversion Processing The color image data format conversion processing in the image conversion circuit 9, which is a feature of this embodiment, will be described in detail below.
[0024]
In the present embodiment, luminance data of R (red), G (green), and B (blue) read by the scanner circuit 1 is converted into C (cyan), M (magenta), Y ( A system in which the density data of yellow) and K (black) is converted and the CMYK data is stored in the storage device 10 and then output by the printer device 2 will be described.
[0025]
FIG. 2 shows a detailed block configuration of the image conversion circuit 9. The image conversion circuit 9 includes an I / O control unit 21 that controls input / output of image data, a feature extraction unit 22-25 that extracts image data features of each color component of CMYK, and a feature extraction unit 22-25. A feature comparison unit 27 that compares the characteristics of the extracted image data of each color component and outputs an instruction according to the comparison result; a format conversion unit 26 that performs format conversion for compression on CMYK image data; An image compression unit 29 that performs image compression, an image expansion unit 30 that expands compressed data, and a format reverse conversion unit 28 that converts the expanded image data into CMYK data.
[0026]
The CMYK image data input from the input / output control circuit 7 is sent to the format conversion unit 26 and simultaneously sent to the feature extraction units 22 to 25. The feature extraction units 22 to 25 each output a result (total value) obtained by adding the change amount of the image data for each CMYK color component for each line, and the total value is sent to the feature comparison unit 27. In the feature comparison unit 27, the total value for each color component is compared with a preset threshold value, and a conversion method is applied to the format conversion unit 26 and the format reverse conversion unit 27 according to the result. Output a signal to specify.
[0027]
Now, with reference to FIG. 3, the format conversion method determination process in the feature comparison unit 27 will be described in detail. FIG. 3 is a flowchart schematically showing the outline of the processing.
[0028]
In the feature comparison unit 27, as a preparation for the format conversion method determination process, the total value of the four components total_L for the amount of change for each line of the image data for each CMYK color component output from the feature extraction units 22-25. Is stored for each line. Further, the total result of each line is accumulated to store the change amount total_S of the entire image. Further, for each line, among the differences for each color component of the change amount, three totals delta of CM, MY, and YK are obtained and stored. In addition, arrays of thr_Li, thr_Si, and thr_Pi are prepared in advance as threshold values for total_L, total_S, and delta. In this array thr_Li, thr_Si, and thr_Pi, the threshold value increases as the value of the argument i increases. The argument i is initialized in advance.
[0029]
In step S301 shown in FIG. 3, first, total_S is compared with thr_Si. When total_S is smaller than thr_Si, it is determined that the amount of change of each color component is small in the entire image, and in step S302, “frame sequential” configured by connecting image data for each color component for each image. Is adopted as the image format before compression. An example of the field sequential format is shown in (1) in FIG.
[0030]
On the other hand, if total_S is larger than thr_Si in step S301, the process proceeds to step S303, where total_L and thr_Li are compared. Here, as the number of lines to be compared, an appropriate number of lines may be taken as a sample in accordance with the balance between the operation speed and the determination accuracy in the image processing system. When total_L is smaller than thr_Li, it is determined that the amount of change of each color component for each line is small, and in step S304, the “line-sequential” configured by connecting the image data of each color component for each line. The format is adopted as the image format before compression. Here, an example of the line sequential format is shown in (2) of FIG.
[0031]
On the other hand, if total_L is greater than thr_Li in step S303, the process proceeds to step S305, where delta and thr_Pi are compared. When delta is smaller than thr_Pi, it is determined that the data change amount of the target line does not change so much in any color component, and the data configuration of each color component is similar, and in step S306, the image data of each color component is converted into one pixel. A “dot-sequential” format configured by concatenating each time is adopted as an image format before compression. Here, an example of the dot sequential format is shown in (3) of FIG.
[0032]
On the other hand, if delta is larger than thr_Pi in step S305, it is determined that it is impossible to determine whether the image data should be converted into frame sequential, line sequential, or dot sequential in order to achieve a high compression ratio. Change the value. That is, by incrementing the value of i in step S307, the respective threshold values are increased, and the possibility of matching with any of the conditions in steps S301, S303, and S305 increases.
[0033]
Thereafter, the comparison determination is performed in the same manner, and when the condition finally matches one of the case of plane sequential, line sequential, or dot sequential, the determination process ends, and the format conversion method is plane sequential, line sequential, dot sequential. It is determined to be one of the sequential.
[0034]
That is, according to the present embodiment, the characteristics of each color component are extracted from the image data stored in the storage device 10, and the image data before compression is converted into the following format according to the extraction result. It is characterized by.
[0035]
1) When the color components of CMYK are very similar, the image data is converted into a dot-sequential format that connects each pixel.
[0036]
2) When the color components of CMYK are not similar to each other and there is little data change in the same line in each color component, the image data of each color component is converted into a line sequential format that connects each line.
[0037]
3) When the color components of CMYK are not similar to each other and there is little change in the data of the entire image in each color component, the image data of each color component is converted into a frame sequential format that connects each screen.
[0038]
When the determination of the optimum format is completed as described above, the feature comparison unit 27 sends the determination result to the format conversion unit 26. The feature comparison unit 27 manages the determined format for each image and grasps the correspondence relationship. As a result, when the compressed image data is output, it is possible to instruct the format inverse conversion unit 28 which format is applied.
[0039]
In the format conversion unit 26, CMYK image data is converted into a format in accordance with an instruction from the feature comparison unit 27. The image data converted into a predetermined format is sent to the image compression unit 29 and subjected to image compression, and then stored in the storage device 10.
[0040]
The data read from the storage device 10 is sent to the image decompression unit 30 and decompressed, and then sent to the format reverse conversion unit 28. The format reverse conversion unit 28 receives the format determination result stored at the time of format conversion from the feature comparison unit 27, reproduces CMYK image data, and outputs it to the input / output control circuit 7.
[0041]
As described above, according to the present embodiment, it is possible to perform efficient compression by extracting the characteristics of the color components constituting the image data and converting the image data before compression into a format according to the extraction result. Therefore, the amount of data after compression is reduced, and the memory area can be effectively used.
[0042]
Second Embodiment
Hereinafter, a second embodiment according to the present invention will be described.
[0043]
In the first embodiment described above, an example in which the present invention is applied to an image processing system has been described. In the second embodiment, an example in which the present invention is applied to an image processing apparatus that encodes read color image data, stores it in a storage unit, and outputs it will be described.
[0044]
FIG. 5 is a side sectional view of a color copying machine, which is an example of an image processing apparatus according to the second embodiment. In the figure, reference numeral 201 denotes an original table glass on which an original 202 to be read is placed. The document 202 is irradiated by the illumination 203 and an image is formed on the CCD 208 by the optical system 207 through the mirrors 204 to 206. Further, the mirror unit 210 including the mirror 204 and the illumination 203 is mechanically driven by the motor 209 at the speed V, and the second mirror unit 211 including the mirrors 205 and 206 is driven at the speed V / 2, whereby the entire surface of the document 202 is driven. Are scanned.
[0045]
An image processing unit 212 processes the read color image as an electrical signal for each color component and outputs it as a print signal.
[0046]
Reference numerals 213 to 216 denote semiconductor lasers for the respective color components, which are driven by the respective print signals output from the image processing unit 212, and the laser beams emitted by the respective semiconductor lasers are photosensitive drums 225 by polygon mirrors 217 to 220. A latent image is formed on .about.228.
[0047]
Reference numerals 221 to 224 denote developing devices for developing the latent image with toners of K, Y, C, and M, respectively, and the developed color toners are transferred to a recording sheet, so that a full color print output can be obtained. Made.
[0048]
The recording paper fed from any of the paper cassettes 229 to 231 and the manual feed tray 232 is adsorbed onto the transfer belt 234 via the registration roller 233 and conveyed. In synchronization with this paper feed timing, toner of each color is developed on the photosensitive drums 225 to 228 in advance, and the toner is transferred onto the recording paper as the recording paper is conveyed.
[0049]
The recording paper to which the toner of each color has been transferred is separated and conveyed from the transfer belt 234, the toner is fixed on the recording paper by the fixing device 235, and is discharged to the paper discharge tray 236.
[0050]
In FIG. 5, reference numerals 201 to 211 denote configurations relating to image reading, which correspond to the scanner circuit 1 shown in FIG. 1 in the first embodiment described above. 5 corresponds to the circuit configurations 8 to 12 including the image input / output control circuit 7 and the storage device 10 shown in FIG. Further, reference numerals 213 to 236 in FIG. 5 are configurations for printing out images, and correspond to the printer apparatus 2 shown in FIG.
[0051]
That is, in the image processing apparatus shown in the second embodiment, the characteristics of the color components constituting the image data are extracted as in the first embodiment, and the image data before compression is formatted according to the extraction result. Can be converted to Accordingly, since efficient compression is possible, the amount of data after compression is reduced, and the memory area in the image processing unit 212 can be effectively used.
[0052]
<Third Embodiment>
The third embodiment according to the present invention will be described below.
[0053]
In the third embodiment, an example in which the present invention is applied to a general-purpose information processing apparatus or system will be described.
[0054]
FIG. 6 shows a block configuration of the information processing apparatus in the third embodiment. In the figure, 101 is a CPU that controls the entire apparatus (system), 102 is a ROM that stores a boot program, BIOS, and the like, 103 is a RAM that is used as a work area of the CPU 101, and the following data or programs are Deployed or secured. Reference numeral 104 denotes a control program corresponding to a series of processing procedures. Reference numeral 105 denotes a buffer area used as a temporary storage location of image data when capturing or printing an image. Reference numeral 106 denotes the entire apparatus including the control program 104. This is an operating system (OS) that controls the above.
[0055]
Reference numeral 107 denotes an image scanner for reading an image, and reference numeral 108 denotes a mass storage device such as a hard disk drive or a magneto-optical disk drive, which corresponds to the storage device 9 shown in FIG. 1 in the first embodiment. The storage device 108 also stores the OS 106 and the like. Reference numeral 109 denotes a configuration for reading data from a portable storage medium, for example, a floppy disk drive. The control program 104 is stored in either the floppy disk set in the floppy disk drive 109 or the hard disk drive 108.
[0056]
Reference numeral 110 denotes a VRAM that develops a bitmap image displayed on the display screen, and 111 denotes a display that displays the bitmap image developed on the VRAM 110.
[0057]
Reference numeral 112 denotes a keyboard for inputting various information, and 113 is a pointing device for designating a desired position displayed on the display screen and for selecting one of various menus. Reference numeral 114 denotes a printer that outputs image data onto a recording medium, and reference numeral 115 denotes an interface for connecting to another host computer via a network or the like.
[0058]
The operation in the configuration shown in FIG. 6 is substantially the same as that of the first embodiment described above. However, the processing executed by the input / output control circuit 7 in the first embodiment is performed by the CPU 101 according to the control program 104. That is, the control program 104 is a program for realizing the processing described in the first embodiment, and can be supplied from the outside via the floppy disk drive 109, for example. Further, the compressed image data in the third embodiment is stored and held in the hard disk drive 108, for example.
[0059]
As described above, also in the information processing apparatus shown in the third embodiment, the characteristics of the color components constituting the image data are extracted in the same manner as in the first embodiment described above, and the image data before compression is extracted as the extraction result. The format can be converted according to the Therefore, since efficient compression is possible, the amount of data after compression is reduced, and the hard disk drive 108 can be effectively used.
[0060]
<Other embodiments>
Note that the present invention can be applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), or a device (for example, a copier, a facsimile device, etc.) including a single device. You may apply to.
[0061]
Another object of the present invention is to supply a storage medium recording a program code of software for realizing the functions of the above-described embodiments to a system or apparatus, and the computer (or CPU or MPU) of the system or apparatus stores the storage medium. Needless to say, this can also be achieved by reading and executing the program code stored in the.
[0062]
In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention.
[0063]
As a storage medium for supplying the program code, for example, a floppy disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.
[0064]
Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an OS (operating system) operating on the computer based on the instruction of the program code. It goes without saying that a case where the function of the above-described embodiment is realized by performing part or all of the actual processing and the processing is included.
[0065]
Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion is performed based on the instruction of the program code. It goes without saying that the CPU or the like provided in the board or the function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.
[0066]
【The invention's effect】
As described above, according to the present invention, a high compression ratio can be obtained by performing compression after conversion to an appropriate data format in consideration of the characteristics of color components constituting image data.
[0067]
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an image processing system according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a configuration of an image conversion circuit in the present embodiment.
FIG. 3 is a flowchart showing format conversion processing in the present embodiment.
FIG. 4 is a diagram illustrating a format example of image data in the present embodiment.
FIG. 5 is a side sectional view of an image processing apparatus according to a second embodiment of the present invention.
FIG. 6 is a block diagram showing a configuration of an information processing apparatus according to a third embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Scanner circuit 2 Printer apparatus 7 Input / output control circuit 8 Buffer memory circuit 9 Image conversion circuit 10 Memory | storage device 11 Determination circuit

Claims (11)

Input means for inputting image data;
Extracting means for extracting features of the image data;
Conversion means for converting the image data into a format corresponding to the feature extracted by the extraction means;
Compression means for compressing the image data converted by the conversion means;
Holding means for holding the image data compressed by the compression means;
Have a,
The extraction means extracts the characteristics of the color components constituting the image data,
The converting means converts the image data into a field sequential format in which each color component is connected for each screen,
In the extracting means, when the change amount for each color component in the entire image data is extracted as a feature that is smaller than a predetermined value, the converting means converts the image data into the frame sequential format. A featured image processing apparatus. Input means for inputting image data;
Extracting means for extracting features of the image data;
Conversion means for converting the image data into a format corresponding to the feature extracted by the extraction means;
Compression means for compressing the image data converted by the conversion means;
Holding means for holding the image data compressed by the compression means;
Have
The extraction means extracts the characteristics of the color components constituting the image data,
The converting means converts the image data into a line-sequential format that connects each color component line by line,
When the extraction means is extracted as a feature that the amount of change for each color component in the predetermined line of the image data is smaller than a predetermined value, the conversion means converts the image data into the line sequential format. An image processing apparatus. Input means for inputting image data;
Extracting means for extracting features of the image data;
Conversion means for converting the image data into a format corresponding to the feature extracted by the extraction means;
Compression means for compressing the image data converted by the conversion means;
Holding means for holding the image data compressed by the compression means;
Have
The extraction means extracts the characteristics of the color components constituting the image data,
The converting means converts the image data into a dot-sequential format that connects each color component for each pixel,
When the extraction means extracts as a feature that a difference between color components for each predetermined line of the image data is smaller than a predetermined value, the conversion means converts the image data into the dot sequential format. An image processing apparatus. Input means for inputting image data;
Extracting means for extracting features of the image data;
Conversion means for converting the image data into a format corresponding to the feature extracted by the extraction means;
Compression means for compressing the image data converted by the conversion means;
Holding means for holding the image data compressed by the compression means;
Have
The extraction means extracts the characteristics of the color components constituting the image data,
The converting means is based on the characteristics of the color components constituting the image data extracted by the extracting means, and the image data is in a frame sequential format in which each color component of the image data is connected for each screen, or An image processing apparatus that converts either a line-sequential format in which each color component of image data is connected for each line or a dot-sequential format in which each color component of the image data is connected for each pixel. The image data is cyan, magenta, yellow, black image processing apparatus according to any one of claims 1 to 4, characterized in that it is constituted by color components of. And an output control means for controlling the output order of the image data held in the holding means, and an output means for outputting the image data on a recording medium in accordance with the output order controlled by the output control means. The image processing apparatus according to claim 1 , wherein the image processing apparatus is an image processing apparatus. An input process for inputting image data;
An extraction step of extracting features of the image data;
A conversion step of converting the image data into a format corresponding to the feature extracted in the extraction step;
A compression step of compressing the image data converted in the conversion step;
A holding step of holding the image data compressed in the compression step in a holding unit;
Have
In the extraction step, the characteristics of the color components constituting the image data are extracted,
In the conversion step, the image data is converted into a frame sequential format in which each color component is connected for each screen,
In the extracting step, when the change amount for each color component in the entire image data is extracted as a feature that is smaller than a predetermined value, the converting step converts the image data into the frame sequential format. An image processing method characterized by the above. An input process for inputting image data;
An extraction step of extracting features of the image data;
A conversion step of converting the image data into a format corresponding to the feature extracted in the extraction step;
A compression step of compressing the image data converted in the conversion step;
A holding step of holding the image data compressed in the compression step in a holding unit;
Have
In the extraction step, features of color components constituting the image data are extracted,
In the conversion step, the image data is converted into a line-sequential format that connects each color component line by line,
In the extraction step, when the change amount for each color component in the predetermined line of the image data is extracted as a feature that is smaller than a predetermined value, the conversion step converts the image data into the line sequential format. An image processing method. An input process for inputting image data;
An extraction step of extracting features of the image data;
A conversion step of converting the image data into a format corresponding to the feature extracted in the extraction step;
A compression step of compressing the image data converted in the conversion step;
A holding step of holding the image data compressed in the compression step in a holding unit;
Have
In the extraction step, the characteristics of the color components constituting the image data are extracted,
In the conversion step, the image data is converted into a dot-sequential format that connects each color component for each pixel,
In the extraction step, when the difference between the color components in each predetermined line of the image data is extracted as a feature, the conversion step converts the image data into the dot sequential format. An image processing method. An input process for inputting image data;
An extraction step of extracting features of the image data;
A conversion step of converting the image data into a format corresponding to the feature extracted in the extraction step;
A compression step of compressing the image data converted in the conversion step;
A holding step of holding the image data compressed in the compression step in a holding unit;
Have
In the extraction step, the characteristics of the color components constituting the image data are extracted,
In the conversion step, based on the characteristics of the color components constituting the image data extracted in the extraction step, the image data is in a frame sequential format in which the color components of the image data are connected for each screen, or An image processing method characterized by being converted into either a line sequential format in which each color component of image data is connected for each line or a dot sequential format in which each color component of the image data is connected for each pixel. 11. A computer-readable recording medium on which a program for causing a computer to execute the image processing method according to claim 7 is recorded .

Images