JP3754734B2 - 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 performing color processing.
[0002]
[Prior art]
Currently known various color recording methods include a thermal transfer method in which ink ribbon ink is transferred by thermal energy, or an ink jet recording method in which recording droplets are ejected and adhered to a recording member such as paper to perform recording. Are known.
[0003]
In particular, the ink jet recording method is a non-impact recording method that does not generate noise during recording, and can perform high-speed recording, and can perform recording without requiring special fixing processing on plain paper.
[0004]
Conventionally, edge detection is performed in a state where each component of Y, M, and C has a high gradation on a host computer, and processing for emphasizing the edge portion is performed to binarize and binary corresponding to each recording agent in the color recording apparatus The image data was transferred to the color recording apparatus.
[0005]
[Problems to be solved by the invention]
However, conventionally, since the edge detection is performed in a state having a high gradation, the edge detection process takes a very long time.
[0006]
The present invention has been made in view of the above points, and an object of the present invention is to detect a black image edge portion at high speed with a simple configuration and to reproduce the black image edge portion with high quality. .
[0007]
[Means for Solving the Problems]
The present invention has been made in view of the above points, and has an input means for inputting M-value color image data composed of a plurality of color components, and a black component by performing inking processing based on the input color image data. Inking processing means for generating data, N-value processing means for performing N-value (M> N) processing on the black component data, and an edge for detecting an edge based on the N-valued black component data Detecting means, and the inking process means generates black component data according to the levels of the plurality of color components.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment according to the present invention will be described in detail with reference to the drawings. In this embodiment, a color inkjet printer will be described as an example of an image processing apparatus that performs color recording.
[0009]
(1) Color image recording device
FIG. 1 is a schematic perspective view showing the configuration of a color inkjet printer to which the present invention is applied.
[0010]
In FIG. 1, reference numeral 202 denotes an ink cartridge, which includes an ink tank in which three color inks of C, M, and Y are placed, and a recording head 201. Reference numeral 103 denotes a paper feed roller that rotates in the direction of the arrow in the drawing while pressing the recording paper 107 together with the auxiliary roller 104 to feed the recording paper 107. Reference numeral 105 denotes a paper feed roller, which, like the paper feed roller 103 and the auxiliary roller 104, conveys the recording paper 107 and plays a role of suppressing the recording paper 107. A carriage 106 supports the three ink cartridges 202 and simultaneously moves the mounted ink cartridge 202 and the recording head 201 together with printing. The carriage 106 is controlled to stand by at a home position indicated by a dotted line in the drawing when the printer is not printing or when the recovery operation of the recording head 201 is performed.
[0011]
Next, an actual printing operation will be described. Before printing is started, the carriage 106 is located at the home position. When a printing start command is received by a control unit (not shown), the recording element provided in the recording head 201 is driven while moving in the X direction in the figure. Then, an area corresponding to the recording width of the recording head 201 is printed on the recording paper 107. Then, when printing is completed up to the end of the recording paper 107 along the scanning direction (X direction) of the carriage 106, the carriage 106 returns to the home position, and the recording paper 107 is moved to an arrow in the figure by the rotation of the paper feed roller 103 and the like. After being conveyed in the direction (Y direction) by a predetermined width, recording in the X direction is started again.
[0012]
In this way, printing on the entire surface of the recording paper 107 is completed by repeating scanning of the recording head 201 for printing (main scanning) and paper feeding of the recording paper 107 (sub-scanning). A recording operation for ejecting ink from the recording head 201 is performed based on control from a recording control unit (not shown).
[0013]
Further, in order to increase the recording speed, recording is not performed only during main scanning (outward) in one direction of the recording head 201, but when the main scanning recording in the X direction is completed and the carriage 106 is returned to the home position side. The recording may be performed in the return path.
[0014]
In the example described above, the ink tank 202 and the recording head 201 are held by the carriage 106 so as to be separable. However, the ink tank 202 that stores recording ink and the ink toward the recording paper 107 are used. Of course, it may be an ink jet cartridge integrated with the recording head 201 for discharging the ink. Further, a multi-color integrated recording head that can eject a plurality of colors of ink from a single recording head may be used.
[0015]
Further, at the home position where the recovery operation described above is performed, a capping unit (not shown) for capping the front surface (ejection port surface) of the recording head 201, and a thickening in the recording head 201 in a capped state by the capping unit. A recovery unit (not shown) that performs head recovery operations such as ink and bubble removal is provided. Further, a cleaning blade (not shown) or the like is provided on the side of the capping unit, and is supported so as to protrude toward the recording head 201 so that it can come into contact with the front surface of the recording head 201. Thus, after the recovery operation, the cleaning blade is projected into the moving path of the recording head 201, and unnecessary ink droplets and dirt on the front surface of the recording head 201 are wiped off as the recording head 201 moves.
[0016]
(2) Description of the recording head 201
Next, the recording head 201 described above will be described in detail with reference to FIG. FIG. 2 is a perspective view of a main part of the recording head 201 shown in FIG. As shown in FIG. 2, the recording head 201 has a plurality of discharge ports 300 formed at a predetermined pitch, and ink is provided along the wall surface of each liquid path 302 that connects the common liquid chamber 301 and each discharge port 300. A recording element 303 for generating ejection energy is provided. The recording element 303 and its circuit are manufactured on silicon by using a semiconductor manufacturing technique. Reference numeral 308 denotes a silicon plate on which electrical wiring for the recording element 303 is provided, and is bonded to a heat radiating aluminum base plate 307. Further, the circuit connecting portion 311 on the silicon plate 308 and the printed board 309 are connected by an extra fine wire 310, and a signal from the printer main body is received via the signal circuit 312.
[0017]
The liquid path 302 and the common liquid chamber 301 are formed by a plastic cover 306 made by injection molding. The common liquid chamber 301 is connected to the ink tank 202 described above via a joint pipe 304 and an ink filter 305, and is configured to be supplied with ink from the ink tank 202. The ink supplied from the ink tank 202 to the common liquid chamber 301 and temporarily stored enters the liquid path 302 by capillary action and forms a meniscus at the discharge port 300 to keep the liquid path 302 filled. At this time, when the recording element 303 is energized through an electrode (not shown) to generate heat, the recording element 303 is rapidly heated and bubbles are generated in the liquid path 302, and ink droplets are ejected from the ejection ports 300 by the expansion of the bubbles. 313 is discharged. Thereby, so-called ink jet recording is performed.
[0018]
(3) Recording control unit
Hereinafter, a configuration for controlling the above-described inkjet recording will be described with reference to FIG. In FIG. 3, reference numeral 400 denotes an interface for inputting an image signal to be recorded, 500 denotes a recording control unit, and 501 denotes a head unit.
[0019]
In the recording control unit 400, 401 is an MPU that comprehensively controls each component based on a control program, and 402 is a program ROM that stores a control program executed by the MPU 401. Reference numeral 403 denotes a dynamic RAM (DRAM) that stores various data (the image signal, recording data supplied to the recording head 201, and the like), and stores the number of replacements of the recording head 201 in addition to the number of recording dots. Can be kept. Reference numeral 404 denotes a gate array that controls supply of print data to the print head 201, and also controls transfer of data among the interface 400, MPU 401, and DRAM 403. Reference numeral 405 denotes a paper feed motor for transporting the recording head 201, and reference numeral 406 denotes a carriage motor for transporting the recording paper 107. Reference numerals 407 and 408 denote motor drivers for driving the paper feed motor 405 and the carriage motor 406, respectively.
[0020]
In the head unit 501, reference numeral 409 denotes a head driver that drives the recording head 201, and 410 denotes a head type signal generation circuit that notifies the MPU 401 of the type of the recording head 201 that is set.
[0021]
In the present embodiment, an example in which the present invention is applied to a system in which a color ink jet having the above-described configuration is used as the color recording apparatus 200 and the color recording apparatus and the host computer 100 are connected will be described.
[0022]
FIG. 4 shows a schematic diagram of the system.
[0023]
The host computer 100 includes a signal generation unit 10 that generates image data indicating a target image, a color processing unit 20 that performs color processing on the image data, and a data transfer unit 30.
[0024]
The color recording apparatus 200 includes an image data storage unit 40 that receives and stores transferred image data, a color conversion unit 60 that performs color conversion on the received image data, an image recording unit, and a recording head 70.
[0025]
Each unit in the host computer 100 and the color recording apparatus 200 is controlled by a control unit (not shown) included in each device.
[0026]
(Color processing part)
The color processing unit 20 in the host computer 100 performs Y, M, C, and Bk corresponding to the output characteristics of the color recording device 200 in order to reduce the time required for image data communication between the host computer 100 and the color recording device 200. To binary data.
[0027]
It is another object of the present invention to make it possible to faithfully reproduce the edge portion in a color recording apparatus for printing three colors (Y, M, C).
[0028]
FIG. 5 shows a specific processing flow of the color processing unit 200 performed based on the control of the control unit.
[0029]
Input RGB correction is performed on the RGB image data indicating the target image generated by the signal generation unit 10 to obtain R1G1B1 image data (S101).
[0030]
In the input γ correction, for example, when the RGB image data depends on the monitor characteristics, γ correction for correcting distortion based on the monitor characteristics is performed for each RGB color.
[0031]
The R1G1B1 image data is subjected to luminance density conversion to obtain CMY image data (S102).
[0032]
Masking processing is performed to correct the mutual color relationship with respect to the CMY image data, thereby obtaining C1M1Y1 image data (S103).
[0033]
UCR / BGR processing is performed on the C1M1Y1 image data, and a Bk signal corresponding to the C1M1Y1 image data is generated by the following processing (S104).
[0034]
Ks = min (C1, M1, Y1)
C2 = C1-UCR (Ks)
M2 = M1-UCR (Ks)
Y2 = Y1-UCR (Ks)
K = BGR (Ks)
The UCR (color component removal) table and the BGR (black generation) table are shown in FIGS.
[0035]
Normally, a black character or graphic data includes a signal value of min (C, M, Y) = 255 (minimum brightness).
[0036]
Conversely, a natural image or the like has almost no signal value of min (C, M, Y) = 255. Therefore, as shown in FIG. 7, the BGR process uses a table in which Bk = 255 and Y = M = C = 0 when min (C1, M1, Y1) = 255. By doing this, it is possible to send black characters or black pixels in graphic data as binary data of k for binary data actually sent to the recording apparatus.
[0037]
On the other hand, the UCR process is performed by a UCR function indicated by a continuous curve as shown in FIG. 6 when Ks has a predetermined value or more.
[0038]
In order to link with the BGR process, 100% UCR is performed when Ks is 255.
[0039]
Further, the UCR function is equivalent to 200% in the UCR table in the halftone area (especially in the vicinity of 255) when the maximum printing amount of Y, M, and C that allows good recording on the color recording apparatus side is 200%. It is desirable to have a curve as shown in FIG. 6 so as not to exceed the driving amount. Of course, the maximum driving amount may be an optimum value according to the printing mode and the recording medium on the color recording apparatus side.
[0040]
According to the UCR / BGR processing, a K signal is generated only for a high density black pixel, so that an edge portion can be easily and quickly extracted based on the binarized K signal on the color image recording apparatus side.
[0041]
Further, since the amount of implantation is controlled for Y, M, and C by the UCR process, the amount of implantation at the halftone density can be controlled while maintaining the continuity of the gradation.
[0042]
That is, by controlling the driving amount of the halftone density, it is possible to reproduce the halftone with high quality without exceeding the maximum driving amount.
[0043]
Then, output γ correction is performed on each of the C2M2Y2K image data (S105), and further binarization processing is performed (S106).
[0044]
(Color converter)
The color-processed Y4M4C4K4 binary image data is received from the host computer 100, and the image data stored in the image data storage unit 40 is color-converted by the color conversion unit 50 into YMC binary image data that well reproduces the edge portion.
[0045]
The configuration of the color conversion unit 50 is shown in FIG.
[0046]
The color conversion unit 50 according to the present embodiment detects the edge portion of the black image from the K4 signal based on the feature that the K4 signal becomes “1” only in the black pixel (Ks = 255) in the color processing unit 20. By performing different mask processes on K4 signals other than the edge portion, the edge portion of the black image can be clearly reproduced.
[0047]
First, a method of creating Y, M, and C masks (Ymask1, Mmask1, and Cmask1) used to convert K4 signals other than the edge portion into YMC signals will be described. In the recording paper used in the present embodiment, it is assumed that a total of 200 dots can be printed (total of all colors) with respect to an area of 100 pixels.
[0048]
Note that the ink ejection amount is set so that the image formation in the printer is favorably performed corresponding to the recording medium.
[0049]
In general, in an inkjet printer using a disposable disposable full head, if at least one color of ink is used up, it is necessary to replace the heads of all the colors. The cost will increase. Therefore, when converting a Bk image that seems to be used frequently in a character image or the like into a YMC image, it is desirable to convert the YMC three-color ink so that it is used as evenly as possible.
[0050]
In the present embodiment, a color conversion mask is created so that the K image is converted equally to each color of YMC. That is, since 200 dots of ink can be applied to 100 pixels on the recording paper, each of Y, M, and C colors is applied to 66 or 67 dots from 200/3 = 66.6... The mask is optimal.
[0051]
In this embodiment, it is assumed that a mask for 8192 pixels (bits) is used for each color of YMC. Of course, the larger the mask size, the more the synchronization between the mask and the image data can be avoided. However, since the memory capacity used in the printer increases, the optimal value is set in consideration of the cost of the printer. Just decide. As a means for creating a mask for each color of YMC, any computer can be used as long as it can secure a necessary memory and can generate a random value.
[0052]
Here, the mask is a color conversion parameter used when the K signal is color-converted into Y, M, and C signals. The mask process is a dot control process.
[0053]
FIG. 9 schematically shows how a color conversion mask is created in the present embodiment, and FIG. 10 is a flowchart thereof.
[0054]
First, in step S121 of FIG. 9, a work memory of 8192 bytes is secured in the computer. For the sake of simplicity, the description will be made assuming that the first address in the memory array of 8192 bytes is 1 address and the last address of 8192 bytes is 8192 address. The reason why the memory of 8192 bytes is secured here is that it is easier to understand if one pixel (any of R, G, B) is assigned to one byte. The memory configuration may be such that the value can be identified.
[0055]
In step S122, in the secured work memory, first, information indicating R at address 1 (hereinafter simply referred to as R), information indicating G at address 2, (hereinafter simply referred to as G), and address 3 Information indicating B (hereinafter simply referred to as B) is stored, and thereafter R, G, and B are sequentially stored up to address 8192. This is shown at 21 in FIG. Note that the numerical value shown at the top in 21 is an address value. By storing RGB in this way, there are no 8192 pixels, R is 2731 pixels, G is 2731 pixels, and B is 2730 pixels.
[0056]
Subsequently, the process proceeds to step S123, and two random numbers are generated in the range of “1” to “8192” by random number generation means in the computer. In step S124, the memory contents at the address indicated by the two random numbers are exchanged. For example, when the generated random numbers are “1” and “9”, the contents “R” at address 1 indicated by X1 in 21 of FIG. 9 are replaced with the contents “B” at address 9 indicated by X2. The results are shown in 22.
[0057]
In step S125, the above-described random number replacement process is repeated a predetermined number of times. In this embodiment, it is repeated 100,000 times. As a result, a random array of R, G, and B is created at addresses 1-8192.
[0058]
In step S126, the address is initialized to "1", and thereafter, Y, M, and C masks are created. In step S127, it is determined whether the content at the address is R, G, or B in the RGB random array, and masks for Y, M, and C are created according to the content. It is assumed that 8192 bits are already secured for each of the Y, M, and C masks as described above.
[0059]
As a method of creating the YMC mask, first, when the content at the address is “R”, the corresponding bits of Y and M (the Nth bit if the address is “N”) are set to “1” in step S128. The corresponding bit of C is set to “0”. If the content at the address is “G”, the corresponding bits of Y and C are set to “1” and the corresponding bit of M is “0” in step S129.
[0060]
If the content at the address is “B”, the corresponding bits of M and C are set to “1” and the corresponding bit of Y is set to “0” in step S130.
[0061]
In step S131, 1 is added to the address. If the address does not exceed the final address value (8192) in step S132, the process returns to step S127 to repeat the YMC mask creation process. In this manner, Y, M, and C masks are generated and stored in the mask storage buffer 1002 as indicated by 23 to 25 in FIG.
[0062]
In this embodiment, since the YMC mask is generated by replacing the Bk image data with RGB pixels, there is a possibility that color misregistration may occur in black ruled lines or the like. Since the colors are arranged at random, the color shift is less noticeable.
[0063]
By creating the masks for the respective colors as described above, ink can be driven by appropriate thinning without using all YMC as on-dots, so that a K image can be reproduced satisfactorily.
[0064]
According to Ymask1, Mmask1, and Cmask1, by generating and using a random YMC mask for limiting the ink ejection amount to a predetermined amount, the Bk image data is converted into YMC image data, thereby recording an image recorded on the recording paper. Thus, problems such as feathering and blurring in black characters and black solid portions can be solved.
[0065]
Further, since the ink hit amount is limited to a predetermined amount by the mask, the ink hit amount limiting process can be performed efficiently.
[0066]
Since Ymask1, Mmask1, and Cmask1 are intended for images other than the edge portion, in order to prevent color blurring, Ymask1, Mmask1, and Cmask1 are set so that a total of 200 dots or less is applied to an area of 100 pixels. Generated.
[0067]
However, if Ymask1, Mmask1, and Cmask1 are used in the edge portion, all of the three components Y, M, and C are not shot in each pixel, so that the edge portion of the black image cannot be reproduced with high density.
[0068]
Further, there is a problem that color blur occurs at the edge portion and the edge portion becomes blurred.
[0069]
Therefore, by providing masks (Ymask2, Mmask2, and Cmask2) for the edge portion, color misregistration is prevented from occurring even for intermediate duty K images.
[0070]
Ymask2, Mmask2, and Cmask2 are masks for edge emphasis, and it is desirable that YMC is recorded with on dots as much as possible. Therefore, in this embodiment, Ymask2, Mmask2, and Cmask2 are processed using an 8 × 8 mask in which all pixels are on (“1”).
[0071]
The Ymask1, Mmask1, Cmask1, and Ymask2, Mmask2, and Cmask2 are stored in the mask storage buffer 54.
[0072]
Hereinafter, the processing of the color conversion unit 50 will be specifically described with reference to FIG.
[0073]
The edge extraction unit 51 extracts an edge part based on the K4 signal and outputs K4 ′.
[0074]
Here, an edge extraction method in the edge extraction unit 1008 will be described with reference to FIG.
[0075]
FIG. 11A shows original Bk image data received from the host computer. In FIG. 10, a pixel for which the Bk image data is on is indicated by “1”, and a pixel for which the Bk image data is off is indicated by “0”.
[0076]
In the present embodiment, when any pixel above, below, left, and right of the target pixel is off (“0”), the target pixel is determined to be an edge region. Even when is off, it may be determined to be an edge region.
[0077]
In order to show the pixel position in the original K signal of (a) of FIG. 11, (d) of FIG. 11 is projected onto (a) of FIG. That is, the pixel position of interest is A, and its value is “1”. The top, bottom, left, and right pixels of the target pixel A are D, E, C, and B, respectively, and have values of “1”, “1”, “0”, and “1”, respectively.
[0078]
Then, in order to determine whether the upper, lower, left, and right pixels of the target pixel A are on, an exclusive OR (XOR) between the target pixel A and the right adjacent pixel B is taken. When the result is Ab, Ab is “0”. Subsequently, XOR with the pixel C on the left, the pixel D on the upper side, and the pixel E on the lower side is sequentially obtained, and Ac, Ad, and Ae are obtained in the same manner. Then, the logical sum (OR) of all the XOR results (Ab, Ac, Ad, Ae) is taken, and the result is set as the value of the target pixel A. In FIG. 11, the target pixel A is “1”. This situation is summarized in the following equation.
[0079]
Ab = A XOR B = 0
Ac = A XOR C = 1
Ad = A XOR D = 0
Ae = A XOR E = 0
A = Ab OR Ac OR Ad OR Ae = 1
[0080]
In this way, by performing the same processing for all the pixels of the original data shown in FIG. 11A, the data shown in FIG. 11B is obtained. According to FIG. 11B, it can be seen that one pixel of the edge of the original image and one pixel around it are extracted by taking XOR in the vertical and horizontal directions.
[0081]
Subsequently, a logical product (AND) of the data of FIG. 11B obtained as a result of XOR and the original data of FIG. As a result, data shown in FIG. 11C is obtained, that is, image data obtained by extracting one edge pixel in the original image.
[0082]
Next, a process of converting the input K signal into Y, M, and C (recording in the Bk conversion unit 52 and the image composition unit 53) will be described with reference to FIG.
[0083]
When binary image data of Y, M, C, and K is transferred from the host computer 100, original data of each color of Y, M, C, and K is stored in the image data storage unit 40 in the printer 100.
[0084]
Then, the Bk converter 52 ANDs the masks Ymask1, Mmask1, and Cmask1 of each color of YMC stored in the mask storage buffer 54 and the K signal to obtain Y5, M5, and C5.
[0085]
Then, the edge extraction unit 51 extracts the edge region K4 ′ from the K signal as described above.
[0086]
In the Bk conversion unit 52, AND of the edge portion data K4 ′ and the respective color masks Ymask2, Mmask2, and Cmask2 is further performed. The results are Y5 ', M5', and C5 ', respectively. Then, in the image composition unit 53, Y5, M5, C5, Y5 ', M5', C5 'and original image data Y4, M4, C4 are ORed for each color. Y6, M6, and C6 obtained as a result are final image data for recording.
[0087]
When the conversion process for the recordable pixels is completed by repeating the processes described above, the color image recording unit 1005 transfers the final image data Y ″, M ″, C ″ to the YMC three-color recording head 201. Thus, image recording in which the Bk image is appropriately reproduced on the recording paper 107 is performed.
[0088]
As described above, the color conversion unit uses a mask in which all of the YMC components are on-dots for the edge portion of the Bk image data to avoid the occurrence of color misregistration, and other regions (non- For the edge portion, Bk image data is converted into YMC image data by generating and using a random YMC mask for limiting the ink ejection amount to a predetermined amount. That is, the edge area and the non-edge area of the K image data can be converted into YMC components at different rates. Therefore, for the edge areas of Bk image data such as isolated points and ruled lines, all of the YMC components can be reproduced at a high density by printing ink with on dots, and for the non-edge areas, the YMC components can be reproduced. By thinning out a predetermined amount, it is possible to reproduce so as not to exceed the driving amount.
[0089]
As a result, edge portions in black characters, black ruled lines, and the like are also emphasized, so that K images can be clearly recorded even in image formation using YMC three-color inks.
[0090]
Also, since the ratio of the edge portion to the image is low, even if all the YMC components are shot on the edge portion with on dots, the maximum shot amount does not exceed 200% in the predetermined area. Bleeding and feathering do not occur and good color reproduction can be performed.
[0091]
In the second embodiment, edge enhancement is also performed for a boundary region with another color in the Bk image data. However, a configuration may be adopted in which edge enhancement is not performed by detecting a boundary with another color.
[0092]
As described above, edge detection can be performed at high speed with a simple configuration based on binarized data by linking UCR / BGR processing and edge detection.
[0093]
Further, the driving amount control in the intermediate density portion and the high density portion can be efficiently and accurately performed by the UCR / BGR process and the mask process.
[0094]
Further, by using different masks for the edge portion and other than the edge portion, the dots in the edge portion can be reproduced clearly and at a high density. That is, black characters and the like can be reproduced with high quality.
[0095]
In the present embodiment, the color processing unit 20 performs the binarization process. However, an N-value conversion process may be used in which the N value is lower than the number of gradations included in the K2C3M3Y3 image data.
[0096]
Further, the BGR process is not limited to that shown in FIG. 7, and a black component may be generated in a high density black pixel.
[0097]
<Other embodiments>
Even if this embodiment is applied to a system composed of a plurality of devices (for example, a host computer, interface device, printer, reader, etc.), a device (for example, a copier, a facsimile device, etc.) composed of a single device. You may apply to.
[0098]
When the present invention is achieved by supplying a recording medium recording a software program for achieving the present invention to a system or apparatus, and the system or apparatus reading and executing the program stored in the recording medium. Needless to say, it can also be applied. As a recording medium for supplying the program, 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.
[0099]
【The invention's effect】
According to the present invention, the edge portion of the black image can be detected at high speed with a simple configuration, and the edge portion of the black image can be reproduced with high quality.
[Brief description of the drawings]
FIG. 1 is a schematic view of a color inkjet printer according to an embodiment of the present invention.
FIG. 2 is a schematic view showing a configuration of an ink jet recording head in the present embodiment.
FIG. 3 is a block diagram showing a configuration of recording control of the ink jet printer according to the present embodiment.
FIG. 4 is a schematic diagram of a system according to the present embodiment.
FIG. 5 is a diagram illustrating processing of a color processing unit according to the present embodiment.
FIG. 6 is a diagram showing a UCR table according to the present embodiment.
FIG. 7 is a diagram showing a BGR table according to the present embodiment.
FIG. 8 is a diagram illustrating a configuration of a color conversion unit according to the present embodiment.
FIG. 9 is a diagram illustrating a process for creating a YMC mask pattern according to the present embodiment.
FIG. 10 is a flowchart showing a process for creating a YMC mask pattern in the present embodiment.
FIG. 11 is a diagram for explaining an edge extraction method in the present embodiment;

Claims (10)

Input means for inputting M-value color image data composed of a plurality of color components;
Inking processing means for generating black component data by performing inking processing based on the input color image data;
N-value processing means for performing N-value (M> N) processing on the black component data;
Edge detection means for detecting an edge based on the N-valued black component data,
The image processing apparatus, wherein the inking process means generates black component data according to the levels of the plurality of color components. 2. The image processing apparatus according to claim 1, wherein the inking process means generates a black component when the input color image data is a high density black pixel. Furthermore, it has a color conversion means for color-converting the black component data into the plurality of color components,
The image processing apparatus according to claim 1, wherein the color conversion unit performs different color conversion on an edge portion and an image other than the edge portion. The image processing apparatus according to claim 3, wherein the color conversion unit turns on all the plurality of color components for the detected edge portion. 4. The image processing apparatus according to claim 3, wherein the color conversion means performs color conversion of the black component data into the plurality of color components so as not to exceed a predetermined driving amount except for the edge portion. The image processing apparatus according to claim 1, wherein the N-value conversion processing unit performs binarization processing. 2. The image processing apparatus according to claim 1, further comprising a lower color removing unit that removes a lower color so as to control a driving amount for the plurality of color component data. 4. The image processing apparatus according to claim 3, further comprising image forming means for forming an image using a recording agent corresponding to each of the plurality of color components. The image processing apparatus according to claim 7, wherein the plurality of color components are Y, M, and C. An input step of inputting M-value color image data composed of a plurality of color components;
Inking process step of generating black component data by performing inking process based on the input color image data;
An N-value processing step of performing N-value (M> N) processing on the black component data;
An edge detection step of detecting an edge based on the N-valued black component data,
In the image processing method, the blacking process step generates black component data in accordance with levels of the plurality of color components.

Images