JP2008149566A - Recording device, recording method, and image processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To record an image with reduced density unevenness in which an edge part of a character or a thin line is sharp in a recording device. <P>SOLUTION: In multipass recording that completes an image with four passes (four-time scanning), an edge part and a non-edge part of an image are detected (S101) and data generation for each scanning is executed so as to record the edge part with one pass and to record the non-edge part with four passes (S102, S103). By this, it is possible to reduce density unevenness while maintaining a sharpness of a character or line drawing that has the edge part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a recording apparatus, an image processing apparatus, and a recording method, and more particularly to a configuration in which a recording mode is different between an edge portion and a non-edge portion of an image.

  2. Description of the Related Art Conventionally, ink jet recording apparatuses that perform recording on various recording media are provided as printers, portable printers, or the like as output media of various apparatuses because they can perform high-density and high-speed recording operations. In this type of ink jet recording apparatus, a recording head having a plurality of ejection openings for ejecting ink and a carriage on which an ink tank is mounted are moved in a predetermined direction (main scanning direction) with respect to the recording medium, and recording is performed between them. A recording scan for discharging ink from the head is performed. Further, during this scanning, the recording medium is conveyed by an amount equal to the recording width in a direction substantially orthogonal to the main scanning direction. Then, by repeating this recording scan and recording medium conveyance, recording is performed on a certain area of the recording medium. This recording method is widely used as a recording method with low running cost and low noise. In recent years, many products suitable for color recording using a plurality of colors of ink have been provided.

  In the recording apparatus, the position and size of the dots finally formed on the recording medium by the recording operation affect the overall recording quality. In the above-described inkjet method, if the ink ejection direction and the ejection amount vary, the dot formation position and size may vary. In the ink jet type recording head, the above-mentioned variation often occurs depending on the characteristics of each head. For example, slight differences that occur at the time of manufacturing the recording head, such as the shape of the ejection port of the recording head and the variation of the electrothermal transducer (ejection heater), affect the ejection amount and ejection direction of the ejected ink, respectively. As a result, the position and size of the dots to be formed are different, and the image quality is ultimately deteriorated due to uneven density of the recorded image.

  On the other hand, there is a method for reducing the above-described density unevenness by performing so-called multi-pass recording, in which a plurality of recording mediums are conveyed, and a plurality of recording heads corresponding to different nozzles are scanned with respect to the same recording area. It has been proposed (for example, Patent Document 1). Also, in this multi-pass printing, a method has been proposed that eliminates the density unevenness using a random mask for a mask that generates data for each of a plurality of scans (for example, Patent Document 2).

JP-A-60-107975 JP 07-052390 A

  However, when characters and fine lines are recorded by the multipass recording method, the sharpness of the edge portions may be impaired. This is due to variations in the conveyance amount in a plurality of recording medium conveyances where multi-pass recording is not scheduled. In other words, due to the variation in the transport amount, a region corresponding to a certain nozzle among a plurality of different nozzles that record the same region may be shifted from a region corresponding to another nozzle. In other words, the landing position of the ink droplet is shifted between scans. This is because the dots are formed so as to exceed the specified position or protrude from the specified position, and the edge portion gives an impression that the outline is not clear.

  The present invention has been made in order to solve the above problems, and the object of the present invention is to provide a recording apparatus capable of recording an image with clear edges of characters and fine lines and reduced density unevenness, It is to provide a recording method and an image processing method.

  Therefore, in the present invention, in the recording apparatus that scans the recording head a plurality of times with respect to the same area of the recording medium, conveys the recording medium during the plurality of scans, and performs recording based on the image data. Detecting means for detecting edge portions and non-edge portions of the image, and for the non-edge portions detected by the detecting means, the recording of the non-edge portions is completed by the plurality of scans. Based on the recording data generated by the data generation means and the data generation means for generating the recording data so as to complete the recording of the edge portion with a smaller number of scans than the plurality of scans, the plurality of scans are performed. And a recording control means for recording the edge portion and the non-edge portion during the plurality of scans.

  In a recording method in which the recording head is scanned a plurality of times on the same area of the recording medium, the recording medium is conveyed during the plurality of scans, and recording is performed based on the image data. For the detection step for detecting a portion and a non-edge portion, and for the non-edge portion detected by the detection step, the recording of the non-edge portion is completed by the plurality of scans, and for the edge portion, the plurality of scans are performed. Based on the data generation step for generating recording data so as to complete the recording of the edge portion with a smaller number of scans, and the recording data generated by the data generation step, the plurality of scans are performed, And a recording control step for recording the edge portion and the non-edge portion during the scanning.

  Further, an image processing method for generating recording data for performing recording based on image data by causing the recording head to scan the same area of the recording medium a plurality of times and conveying the recording medium during the plurality of times of scanning. And detecting the edge portion and the non-edge portion of the image in the image data, and for the non-edge portion detected by the detecting means, the recording of the non-edge portion is completed by the plurality of scans. And a data generation step of generating recording data so as to complete the recording of the edge portion by scanning fewer times than the plurality of scans.

  According to the above configuration, the edge portion and the non-edge portion in the image are detected, and the number of recording scans of the edge portion is made smaller than the number of recording scans of the non-edge portion. Thereby, in the recording of the edge portion, even if there is a conveyance error of the recording medium, it is possible to reduce the number of conveyances that may cause a conveyance error for the edge portion recording, and it is possible to maintain the sharpness of the edge of the character or line drawing, Recording with less density unevenness is possible.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the embodiments described below, a printer is taken as an example of a recording apparatus using an inkjet recording method.

(1) Schematic Configuration of Color Recording Device FIG. 1 is a perspective view showing a schematic configuration of a color inkjet printer according to an embodiment of the present invention. In this figure, reference numeral 1202 denotes an ink cartridge (ink tank) containing four color inks (black, cyan, magenta, yellow). The ink accommodated in these is supplied to the corresponding color ink recording head 1201 provided with a row of nozzles (also referred to as ejection ports). Reference numeral 1106 denotes a carriage. The four ink cartridges 1202 and the recording head 1201 are detachably mounted and can be moved. The carriage 1106 moves to the home position indicated by the broken line in the drawing and waits when the recording operation is not performed or when the recovery operation of the recording head is performed.

  Reference numeral 1103 denotes a paper feed roller, which rotates with the auxiliary roller 1104 to convey a recording paper 1107 as a recording medium in the direction of the arrow in the figure. Together with the roller pair 1105 on the upstream side of the recording head, these rollers 1103 and 1104 apply tension to the recording paper 1107 to keep the recording paper surface flat.

  When there is a recording start command, the carriage 1106 located at the home position before starting recording moves in the x direction and discharges ink from the nozzles provided in the recording head 1201 according to the recording data to correspond to the nozzle width of the recording head. The recorded area is recorded (recording scan). When recording is completed up to the end of the sheet along the carriage movement direction, the carriage returns to the original home position, and recording is performed again while moving in the x direction. The paper feed roller 1103 rotates in the direction of the arrow shown in the drawing and the paper is fed in the y direction by a required amount before the next print scan is started after the print scan is completed. By repeating the recording scanning and paper feeding in this way, recording on one recording paper is completed.

  In order to increase the recording speed, recording is not performed only during scanning in one direction, but recording is also performed in the return path when the recording of scanning in the x direction ends and the carriage returns to the home position side. Also good. In the example described above, the ink tank and the recording head are mounted on the carriage 1106 in a separable manner. Of course, an ink jet cartridge in which an ink tank 1202 for storing ink and a recording head 1201 for discharging ink toward the recording paper 1107 are integrated may be used. Furthermore, a multi-color integrated recording head that can eject a plurality of colors of ink from one recording head may be used.

  Also, at the position where the recovery operation is performed, a capping mechanism (not shown) that caps the front surface (ejection port surface) of the head, or a head that removes thickened ink and bubbles in the recording head in a capped state by the capping mechanism A recovery unit (not shown) that performs a recovery operation is provided. Further, a cleaning blade (not shown) or the like is provided on the side of the capping mechanism, and is supported so as to protrude toward the recording head 1201 so that it can come into contact with the front surface of the recording head. Thus, after the recovery operation, the cleaning blade is projected into the moving path of the recording head, and unnecessary ink droplets and dirt on the front surface of the recording head are wiped off as the recording head moves.

(2) Recording Head Next, the recording head 1201 will be described with reference to FIG. FIG. 2 is a perspective view showing a main part of the recording head 1201 shown in FIG. As shown in FIG. 2, the recording head 1201 is provided with a plurality of ejection ports 2300 at a predetermined pitch, and ink along the wall surface of each liquid path 2302 that connects the common liquid chamber 2301 and each ejection port 2300. An electrothermal conversion element 2303 for generating energy for discharge is provided. The electrothermal conversion element 2303 and its circuit are made on a silicon substrate using semiconductor manufacturing technology. Further, a temperature sensor (not shown) and a sub-heater (not shown) are collectively formed on the same silicon by the same semiconductor manufacturing process. The silicon plate 2308 on which these electric wirings are made is bonded to an aluminum base plate 2307 that can dissipate heat. Further, the circuit connection portion 2311 on the silicon plate and the printed circuit board 2309 provided with the signal circuit 2312 are connected by an extremely thin wire 2310, and a signal from the recording apparatus main body can be received via the signal circuit 2312.

  The liquid path 2302 and the common liquid chamber 2301 are formed of a plastic cover 2306 made by injection molding. The common liquid chamber 2301 is connected to the above-described ink cartridge (see FIG. 1), the joint pipe 2304, and the ink filter 2305, whereby ink is supplied from the ink cartridge to the common liquid chamber 2301. The ink supplied to the common liquid chamber 2301 and temporarily stored moves to the liquid path 2302 by capillary action, forms a meniscus at the discharge port 2300, and keeps the liquid path 2302 filled. At this time, when the electrothermal conversion element 2303 is energized through an electrode (not shown) and heat is generated, the ink on the electrothermal conversion element 2303 is rapidly heated to generate bubbles in the liquid path 2302, and the bubbles are generated. An ink droplet 2313 is ejected from the ejection port 2300 by the expansion.

(3) Control Configuration Next, a control configuration for executing recording control of each part of the apparatus configuration will be described with reference to the block diagram shown in FIG. In the figure, reference numeral 3400 denotes an interface for inputting a recording signal from a host device such as a personal computer. Reference numeral 3401 denotes an MPU, which executes processing in the mass recording apparatus, starting with processing described later with reference to FIGS. Reference numeral 3402 denotes a program ROM for storing a control program executed by the MPU 3401. Reference numeral 3403 denotes a dynamic RAM (DRAM) for storing various data (such as the recording signal and recording data supplied to the head). . The RAM 3403 can also store the number of recording dots, the number of ink recording head replacements, and the like. Reference numeral 3404 denotes a gate array that controls supply of print data to the print head, and also controls data transfer between the interface 3400, the MPU 3401, and the DRAM 3403. Reference numeral 3406 denotes a carriage motor (CR motor) for conveying the recording head, and 3405 denotes a conveyance motor (LF motor) for conveying the recording paper. Reference numerals 3407 and 3408 denote motor drivers for driving the transport motor 3405 and the carriage motor 3406, respectively. Reference numeral 3409 denotes a head driver for driving the recording head 1201.

(Embodiment 1)
Outline of Embodiment 1 In the first embodiment of the present invention, edge portions and non-edge portions of an image are detected in multi-pass printing in which an image is completed in four passes (four scans), and one edge portion is passed. The data for each scan is generated so that the non-edge portion is recorded in four passes. This makes it possible to reduce density unevenness while maintaining the sharpness of characters and line drawings having edge portions.

Scan Data Generation Processing FIG. 4 is a flowchart showing print data generation processing for each scan according to this embodiment.

  First, edge portions and non-edge portions are detected in the image data (S101). Subsequently, a one-pass division mask process is performed on the detected edge portion so that an image is completed in one pass (S102). The detected non-edge portion is subjected to 4-pass division mask processing so that an image is completed in 4 passes (S103). Then, the edge data and the non-edge data obtained by performing the above pass division mask processing are synthesized to generate print data for one scan (S104). After this data is generated, scanning for printing once out of four-pass printing is performed. Note that the present invention is not limited to the form in which print data used for each scan is generated for each scan as in the above example. For example, before performing the recording for one page, the recording data for the scanning required for the page may be generated by repeating the scanning in steps S101 to S104, and then the recording operation may be performed.

Edge Part and Non-Edge Part Detection FIG. 5 is a flowchart showing details of the edge part and non-edge part detection processing in step S101.

  First, it is determined whether or not a black dot exists in the set target pixel and the total number of black dots present in a 3 × 3 pixel matrix centered on the target pixel is 9 (S201). ). If the total number of black dots is 9, the bit of the target pixel is turned on (S202). Otherwise, the bit of the pixel of interest is turned off (S203). Next, the target pixel is shifted to the next pixel, and the pixel is set as the target pixel (S204). Then, it is determined whether or not the processing has been completed for all the pixels to be processed (S205). If all the processing has not been completed, the above processing is repeated.

  In this example, an edge is detected for a black character or line diagram, but the present invention is not limited to this. For example, the present invention can be applied to the case of recording color characters, diagrams, or figures having a predetermined color. In this case, for colors such as cyan, magenta, and yellow constituting the color, edge detection for counting the number of dots of those colors and processing based thereon are performed in the same manner as described above.

  6A to 6D are diagrams for explaining an example of the non-edge portion detection process in step S201. FIG. 6A shows a 3 × 3 pixel matrix centered on the pixel of interest. FIG. 6B shows original image data to be recorded. For example, in a predetermined pixel region (the region of 10 pixels × 10 pixels in FIG. 6B) having the original data, the processing is performed while sequentially shifting the pixel of interest one pixel at a time. For example, in the region shown in FIG. 6B, the pixel is shifted from the uppermost pixel to the right end in the right direction, and then similarly shifted from left to right in the second pixel column from the top. Further, the same movement is performed in the third pixel row from the top. In this way, the number of dots of 3 pixels × 3 pixels including the target pixel as a center is examined while sequentially moving the target pixel.

  In the image shown in FIG. 6B, when the bit of the pixel of interest is turned on when the total number of black dots in the matrix is 9, the non-edge portion data shown in FIG. 6C can be obtained. . Then, the non-edge portion data is inverted and a logical product with the original data is obtained. Thereby, edge part data can be obtained as shown in FIG. In this example, the edge portion is detected as a contour pixel, and the non-edge portion is detected as a region other than the contour pixel. However, the present invention is not limited to this, and the edge portion may be detected as a plurality of pixels, and this number can be determined in consideration of the sharpness of the target edge portion.

Pass division method Figure 7 of the edge portions and non-edge portion (a) and (b) are diagrams for explaining a pass division processing of step S102, S103 of the edge portions and non-edge portion.

  FIG. 7A shows an edge portion mask 300. In the 4-pass multi-pass printing according to the present embodiment, the width of this 1/4 is obtained in four scans by feeding the paper for a quarter of the length of the nozzle row ejecting black ink in the print head 1201. Complete the recording of the area. Therefore, print (dot) data is generated using a mask composed of four divided masks having a size corresponding to a width of 1/4.

  In the present embodiment, the recording is completed by one scan with respect to the edge portion. As a result, in the case of four passes, the conveyance of the recording medium four times affects the recording, whereas the recording in one scanning causes a variation in the conveyance amount (if any) at the dot formation position. It is possible to perform recording without reducing the influence and sharpness of the edge portion.

  Specifically, regarding the edge portion mask composed of four divided masks 301, 303, 305, and 307, only the divided mask 307 is set to 100% duty, and the others are set to 0% duty. That is, all the pixels 308 of the division mask 307 are turned on (the contents of the recording data are output as they are) (100% duty mask). On the other hand, the other divided masks 301, 303, and 305 have mask contents (0% duty) that turn off all of the pixels 302, 304, and 306 (mask the contents of the recording data). The four divided masks 301, 303, 305, and 307 generate print data for the fourth pass, the third pass, the second pass, and the first pass, respectively, of the four scans for printing the predetermined area. It is a mask used for. Therefore, in the present embodiment, the edge portion is recorded (completed) in the first pass.

  On the other hand, FIG. 7B shows a non-edge portion mask 400. The non-edge portion completes recording with 4 passes. For this reason, the non-edge portion mask 400 is obtained by using four divided masks 401, 403, 405, and 407 as 25% duty masks. Further, in order to maintain the complementary relationship in four scans, the complementary relationship is maintained in units of 2 pixels × 2 pixels 402, 404, 406, and 408 in each division mask. These divided masks 401, 403, 405, and 407 are masks used for generating print data for the fourth pass, the third pass, the second pass, and the first pass in 4-pass printing, respectively.

  8A to 8F are diagrams schematically illustrating a dot formation process in the edge portion and the non-edge portion according to the present embodiment. The overall size of the “T” shown in FIG. 8 is the size of the divided masks 301, 303, 305, 307 and divided masks 401, 403, 405, 407 shown in FIGS. This will be described as the size included. However, the magnitude relationship between the mask size and the image size is not essential as is apparent from the following description. When the size of one target image is larger than the division mask, the image may be recorded in four passes as different areas.

  FIG. 8A shows original image data of “T-shape” in which the pixel 200 is black data. As shown in FIG. 8B, the edge portion pixel (dot data) 201 and the non-edge portion pixel (dot data) 202 are obtained by performing the above-described edge portion and non-edge portion detection processing on the original data. To detect.

  The edge pixel 201 is logically ANDed with the edge division mask 307 shown in FIG. 7A in the first pass recording data generation, thereby generating the first pass data of the edge portion. Is done. On the other hand, in the first pass data generation for the non-edge portion pixel 202, the logical product with the non-edge portion division mask 407 shown in FIG. 7B is taken, and the first pass data of the non-edge portion is generated. . Then, the first pass data of the edge portion and the non-edge portion obtained as described above are combined to obtain print data of the first pass (first scan) shown in FIG. Here, the pixel 203 represents an edge pixel recorded in the first pass, and the pixel 204 represents a non-edge pixel recorded in the first pass. In the first pass, the edge portion of the T character is completed, and almost ¼ of the dots constituting the non-edge portion are formed.

  Next, print data for the second pass is generated using the divided mask with the mask position shifted by a quarter of the nozzle row of the print head with respect to the original data. That is, since all data has already been generated for the first portion of the edge portion, data generation of the edge portion is not performed. On the other hand, the non-edge pixel 202 is logically ANDed with the division mask 405 for the second pass, and print data for the second pass shown in FIG. 8D is generated. Here, a pixel 205 indicated by a dark color represents a pixel recorded in the first pass, and a pixel 206 represents a non-edge pixel recorded in the second pass.

  By performing the same processing using the divided masks 403 and 401, print data of the non-edge pixels in the third pass and the fourth pass shown in FIGS. 8E and 8F are generated. In FIG. 8E, a pixel 207 represents a pixel recorded in the first pass or the second pass, and a pixel 208 represents a non-edge pixel recorded in the third pass. In FIG. 8F, a pixel 209 represents a pixel recorded in the first pass to the third pass, and a pixel 210 represents a non-edge pixel recorded in the fourth pass.

  As described above, the edge portion and the non-edge portion in the image to be recorded are detected, and the edge portion is completed in one pass and the non-edge portion is recorded in four passes. As a result, it is possible to record a high-quality image with less density unevenness in the solid portion while maintaining the sharpness of the edge portion such as characters and line drawings.

(Embodiment 2)
Outline of Embodiment 2 The present embodiment relates to a configuration that prevents the use nozzle from being biased by using only the same nozzle with respect to the edge portion, and improves the nozzle durability. The configuration of the present embodiment is the same as that of the first embodiment described above, except as described below.

Edge portion mask switching FIGS. 9A to 9D are views for explaining division mask switching in the present embodiment.

  In the mask processing for the edge portion after detecting the edge portion and the non-edge portion, four types of masks are used as the edge portion mask as shown in FIG. That is, this embodiment is also a 4-pass multi-pass printing as in the first embodiment, and in this case, the edge portion printing is completed in one pass. However, the four masks corresponding to the nozzle positions are used by switching the divided masks used for generating the print data for the one-pass printing.

  A mask 500 shown in FIG. 9A is a mask for recording the edge portion in the first pass, and the divided mask 504 has a 100% duty and the others have a 0% duty. A mask 530 shown in FIG. 9B is a mask for recording the edge part in the second pass, and the divided mask 533 has a 100% duty and the others have a 0% duty. Further, a mask 540 shown in FIG. 9C is a mask for recording the edge portion in the third pass, and the divided mask 542 has a 100% duty and the others have a 0% duty. Finally, a mask 550 shown in FIG. 9D is a mask for recording the edge portion in the fourth pass, and the divided mask 551 has a 100% duty and the others have a 0% duty.

  These masks can be switched in page units or job units, for example. Thereby, it becomes possible to eliminate the unevenness of the nozzles used.

(Embodiment 3)
Outline of Embodiment 3 This embodiment relates to a configuration for determining whether or not to perform edge detection according to an object attribute. That is, for characters and line drawings, edge portions and non-edge portions are detected and the number of recording passes is made different between them. On the other hand, halftone portions such as photographic images are recorded as non-edge portions without performing the above detection. To do. As a result, it is possible to satisfactorily achieve both sharpness of characters and the like and reduction in density unevenness in the halftone portion.

  FIG. 10 is a block diagram for explaining the processing of this embodiment, and the printer main body side is mainly composed of the recording control unit explained in FIG.

  In FIG. 10, the host PC (1200) renders input RGB data 1000 received from the application at a resolution of 600 dpi. In this rendering, multi-value RGB data 1003 in bitmap format is generated, and character data 1200 is extracted and separated as binary data of 600 dpi. In addition to character data, for example, line drawing data may be extracted and separated as an image having an edge portion.

  The generated multi-value RGB data 1003 and character data 1002 are transferred to the printer main body 1210. In the printer main body, conversion processing (1004) is performed on the multi-value RGB data 1003 to convert it into multi-value KCMY data. The converted KCMY data is binarized (1005) by a predetermined quantization method. Here, it is converted into binary data of 600 dpi by error diffusion.

  On the other hand, for the character data 1002, the edge detection process (1011) described above in step S101 in FIG. 4 is performed to generate character edge data 1012. The character edge data includes edge data and non-edge data as distinguished from character data.

  Next, the pass division processing (1008) described above with respect to steps S102 and S103 in FIG. 4 is performed on the binary data 1007 and character edge data 1012 of K, C, M, and Y. That is, of the character edge data 1012, the edge portion data is subjected to a mask process for recording in one pass as described in the first and second embodiments. On the other hand, the non-edge portion data and the binary data 1007 of the character edge data 1012 are similarly subjected to a mask process for recording in four passes as described in the first and second embodiments. Through the above processing, character edge recording data 1009 that completes recording in one pass and non-character edge recording data (1010) that completes recording in four passes are generated. Finally, these data are combined to generate recording data (1013) for each pass.

  As described above, according to the present embodiment, by determining whether or not to perform edge detection according to an object, it becomes possible to accurately determine the edge portion and halftone portion of a character or line drawing, and the sharpness of the edge portion. And the reduction in density unevenness in the halftone portion can be satisfactorily achieved.

(Other embodiments)
In the embodiment described above, the contents of the mask are determined regardless of the type or characteristic of the recording medium. However, a plurality of edge portion masks and non-edge portion masks are used according to these types or characteristics. Also good. Thereby, the sharpness of the edge and the reduction in density unevenness can be optimized according to the recording medium.

  In the above-described embodiment, edge detection and mask processing based on the edge detection are performed as image processing in the recording apparatus. However, the present invention is not limited to this. In a personal computer as a host device, edge detection, mask processing based on the edge detection, and synthesis processing may be performed. In this specification, the execution of these image processes in the recording apparatus and the host apparatus is included in the execution of the image processing method to which the present invention is applied.

  Furthermore, although the number of passes for recording the edge portion is 1 in the above example, the present invention is not limited to this. For example, the number of passes for recording the edge portion can be determined according to the degree of error of the recording medium conveyance performed each time scanning is completed. In this case, it is a matter of course that the number is less than the number of passes for recording the non-edge portion.

  Further, in the above-described embodiment, an example in which the present invention is applied to an ink jet recording type recording apparatus has been described, but the recording apparatus is not limited to this type. The present invention can be applied to any type of recording apparatus as long as it is a recording apparatus that performs recording by forming dots by the multi-pass method.

1 is a perspective view illustrating a schematic configuration of a color inkjet printer according to an embodiment of the present invention. FIG. 2 is a perspective view illustrating a main part of the recording head illustrated in FIG. 1. FIG. 2 is a block diagram illustrating a control configuration for executing recording control in the recording apparatus illustrated in FIG. 1. 6 is a flowchart illustrating print data generation processing for each scan according to the first embodiment of the present invention. 5 is a flowchart showing details of edge portion and non-edge portion detection processing shown in FIG. 4. (A)-(d) is a figure explaining an example of the detection process of the non-edge part shown in FIG. (A) And (b) is a figure explaining the path | pass division | segmentation process of the edge part of step S102, S103, and a non-edge part. (A)-(f) is a figure which shows typically the dot formation process in the edge part of this embodiment, and a non-edge part. (A)-(d) is a figure explaining switching of the division mask in this embodiment. It is a block diagram explaining the process of 3rd embodiment of this invention.

Explanation of symbols

1011 Edge detection 1008 Pass division processing 1201 Print head 3401 MPU
3402 ROM
3403 DRAM
3404 Gate array 3405 Paper feed motor 3406 Carriage motor 3500 Recording control unit

Claims (15)

In a recording apparatus that scans a recording head a plurality of times with respect to the same area of a recording medium, conveys the recording medium during the plurality of scans, and performs recording based on image data.
Detecting means for detecting edge portions and non-edge portions of the image in the image data;
For the non-edge portion detected by the detection means, the recording of the non-edge portion is completed by the plurality of scans, and for the edge portion, the recording of the edge portion is performed by a fewer number of scans than the plurality of scans. Data generation means for generating recording data to be completed;
Recording control means for performing the plurality of scans based on the recording data generated by the data generation means, and recording an edge portion and a non-edge portion during the plurality of scans;
A recording apparatus characterized by comprising:   The recording apparatus according to claim 1, wherein the recording control unit records the edge portion by one scan.   The recording apparatus according to claim 1, wherein the data generation unit generates print data using a mask configured by a divided mask corresponding to the plurality of scans.   The image data has an object attribute that separates character or line drawing data and bitmap data in pixel units, and the detection means determines whether to detect the edge portion and the non-edge portion according to the object attribute. 4. The recording apparatus according to claim 1, wherein the recording apparatus is determined.   The recording apparatus according to claim 4, wherein the detection unit detects an edge portion and a non-edge portion only for a pixel having a character or line drawing attribute among the object attributes.   The recording apparatus according to claim 1, wherein the number of scans of the edge portion and the non-edge portion is switched according to a type of the recording medium. In a recording apparatus that scans a recording head a plurality of times with respect to the same area of a recording medium, conveys the recording medium during the plurality of scans, and performs recording based on image data.
A recording apparatus comprising recording control means for recording edge portions in image data by the plurality of scans and recording non-edge portions by a smaller number of scans than the plurality of scans. In a recording method in which a recording head is scanned a plurality of times with respect to the same area of a recording medium and the recording medium is conveyed during the plurality of scans to perform recording based on image data.
A detection step of detecting an edge portion and a non-edge portion of the image in the image data;
For the non-edge portion detected by the detection step, the recording of the non-edge portion is completed by the plurality of scans, and for the edge portion, the recording of the edge portion is performed by a fewer number of scans than the plurality of scans. A data generation process for generating record data to be completed;
Based on the recording data generated by the data generation step, a recording control step of performing the plurality of scans and recording an edge portion and a non-edge portion during the plurality of scans;
A recording method characterized by comprising:   The recording method according to claim 8, wherein the recording control step records the edge portion by one scan.   10. The recording method according to claim 8, wherein the data generation step generates print data using a mask configured by a divided mask corresponding to the plurality of scans.   The image data has an object attribute that separates character or line drawing data and bitmap data in pixel units, and the detection step determines whether to detect the edge portion and the non-edge portion according to the object attribute. 11. The recording method according to claim 8, wherein the recording method is determined.   12. The recording method according to claim 11, wherein the detecting step detects an edge portion and a non-edge portion only for a pixel having a character or line drawing attribute among the object attributes.   The recording method according to claim 8, wherein the number of scans of the edge portion and the non-edge portion is switched according to a type of the recording medium. In a recording method in which a recording head is scanned a plurality of times with respect to the same area of a recording medium and the recording medium is conveyed during the plurality of scans to perform recording based on image data.
A recording method comprising: a recording control step of recording an edge portion in image data by the plurality of scans and recording a non-edge portion by a smaller number of scans than the plurality of scans. In an image processing method for generating recording data for performing recording based on image data by causing a recording head to scan the same area of the recording medium a plurality of times and transporting the recording medium during the plurality of times of scanning.
A detection step of detecting an edge portion and a non-edge portion of the image in the image data;
For the non-edge portion detected by the detection step, the recording of the non-edge portion is completed by the plurality of scans, and for the edge portion, the recording of the edge portion is performed by a fewer number of scans than the plurality of scans. A data generation process for generating record data to be completed;
An image processing method characterized by comprising:

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