JP5146085B2 - Image processing apparatus and program - Google Patents

Description

  The present invention relates to an image processing apparatus that processes image data.

  In recent years, high-density bar code information represented by, for example, EAN128 has been widely used. For example, in Patent Document 1, the direction of a bar code bar is detected, and correction is made to vary the number of black bar dots and the number of white bar dots in print data in accordance with the bar code bar direction, ambient temperature or humidity. Is doing. As a result, the black and white bar widths having stable line widths are reproduced and printed regardless of changes in the printing apparatus over time, environmental fluctuations, and barcode directions.

JP 2006-293916 A

  The barcode is sometimes pasted and printed as raster data (image object) such as a bitmap image. At this time, if the barcode quality is important, it is necessary to create data with high resolution for the entire raster data. For this reason, an image portion (for example, a photographic data portion such as a natural image) where the image quality deterioration is not so noticeable even at a low resolution is unnecessarily increased in resolution, the entire data amount increases, and the processing time for image output ( Throughput). Further, in order to suppress the entire data amount, an image of resolution conversion for reducing the resolution (for example, conversion for reducing the resolution of a barcode image pasted at 600 dpi to 200 dpi) in accordance with image data whose image quality deterioration is not conspicuous. When the process is executed, the reading accuracy deteriorates due to the thickening or crushing of barcode printing.

The invention of claim 1 includes an acquisition unit that acquires image data, and a first region that has barcode information and a second region that does not have barcode information from the image data acquired by the acquisition unit. An image to be detected and a first image process for the first region detected by the detection unit, and a second image process different from the first image process for the second region. And the first image processing performed by the image processing unit is performed by performing resolution conversion image processing for increasing the resolution on the first region. The second image processing performed by the image processing unit performs resolution conversion image processing for lowering the resolution on the second area, with the resolution of the image data constituting the first resolution being the first resolution. In the second territory An image processing apparatus according to claim a resolution of the image data constituting be the lower than the first resolution a second resolution.

According to a second aspect of the invention, the image processing apparatus according to claim 1, wherein said image processing unit, wherein the image of the first of the bar code information in the region, the coloring material of 100% alone, or two It is characterized in that image processing for color conversion for reproduction with a combination of 200% of color materials is performed.
According to a third aspect of the present invention, in the image processing apparatus according to the first or second aspect , the image processing unit is in the first region so as to print using a color material of K (black) alone. It is characterized in that image processing for color conversion is performed on an image of barcode information.

According to a fourth aspect of the present invention, in the image processing apparatus according to any one of the first to third aspects, the image processing unit does not use any color material for the background portion of the barcode information in the first area. The image processing is performed so that printing is performed at

A fifth aspect of the present invention is the image processing apparatus according to any one of the first to fourth aspects , further comprising a bar code type detecting unit that detects a bar code type for the bar code information, and the image processing unit includes: The bar code type detected by the bar code type detection unit is stored in advance from a plurality of parameter tables in which presence / absence of execution of digital filter processing, gradation correction processing, compression processing, and output device processing as predetermined parameters is stored. Accordingly, a preferable parameter table is selected and the first image processing is performed.

According to a sixth aspect of the present invention, there is provided an image processing apparatus according to any one of the first to fifth aspects , wherein a bar code image quality is detected by analyzing a signal value of the bar code information for the bar code information. The image processing unit further includes a code quality detection unit, and the image processing unit includes a plurality of parameter tables in which presence / absence of execution of digital filter processing, gradation correction processing, compression processing, and output device processing is stored in advance as predetermined parameters. A preferable parameter table is selected in accordance with the quality of the barcode image detected by the code quality detection unit, and the first image processing is performed.

According to a seventh aspect of the present invention, in the image processing apparatus according to any one of the first to sixth aspects , the image processing unit detects a direction of a barcode forming the barcode information, and a main scanning direction of image formation On the other hand, if each line of the barcode is horizontal, the image data is corrected so that the line width becomes thick.

According to an eighth aspect of the present invention, in the image processing device according to any one of the first to seventh aspects , the detection unit detects a region having image data as the second region, and the image processing unit performs the detection. In the first image processing, the outline of the image portion in the barcode information is set after the resolution of the image data constituting the first area is set to the first resolution with respect to the first area. The second image processing performed by the image processing unit is performed by performing edge enhancement processing for clarifying and signal correction processing for increasing the contrast between the image portion and the background portion in the barcode information. The second area is subjected to a smoothing process for reducing noise in the image data after the resolution of the image data constituting the second area is set to the second resolution. That.

According to a ninth aspect of the present invention, in the image processing device according to the eighth aspect , the detection unit further detects a region having text data from the image data acquired by the acquisition unit as a third region, and The image processing unit performs resolution conversion image processing on the third region detected by the detection unit, so that the resolution of the image data constituting the third region is higher than the second resolution. After the third resolution is set to be high, third image processing for performing edge enhancement processing for clarifying the outline of the text portion in the text data is performed.

According to a tenth aspect of the present invention, in the image processing device according to any one of the first to ninth aspects , the barcode area unit or the pixel unit of the image data constituting the first area detected by the detection unit is A tag information adding unit that adds tag information indicating the presence of the barcode information; and the image processing unit performs the first image processing on the first region based on the tag information. Features.

According to the eleventh aspect of the present invention, a computer for performing image processing has a function of acquiring image data, and a first area having barcode information and a second area not having barcode information from the acquired image data. And a function of performing first image processing on the detected first area and performing second image processing different from the first image processing on the detected second area. In the first image processing, the resolution of the image data constituting the first area is set to the first area by performing resolution conversion image processing for increasing the resolution on the first area. a first resolution, the second image processing, to the second region, by performing image processing of resolution conversion of lowering the resolution, the resolution of the image data constituting the second region From the first resolution Is a program which is characterized in that the lower second resolution.

According to a twelfth aspect of the present invention, in the program according to the eleventh aspect , the first image processing is for printing an image of the barcode information in the first area using a single color material. Image processing is performed.

According to a thirteenth aspect of the present invention, in the program according to the eleventh or twelfth aspect , the computer further realizes a function of detecting a bar code type and / or a bar code image quality for the bar code information. The first image processing includes a plurality of parameter tables in which presence / absence of execution of digital filter processing, gradation correction processing, compression processing, and output device processing is stored in advance as predetermined parameters. Alternatively, a preferable parameter table is selected according to the quality of the barcode image, and image processing is performed.

According to a fourteenth aspect of the present invention, in the program according to any one of the eleventh to thirteenth aspects , the bar code area unit or pixel unit of the image data constituting the first area detected by the computer is detected by the computer. A function of adding tag information indicating the presence of information is further realized, and the first image processing performs the first image processing on the first area based on the tag information. .

According to claim 1, in a state where the barcode image is maintained at a high resolution, for example, data of a natural image or the like can be reduced in resolution than the barcode image, and an area not including the barcode and an area including the barcode are included. Compared to the invention with the same resolution, it is possible to maintain the reading accuracy of barcode characters and suppress the data amount of the entire image.
According to the second aspect , compared with the case where the present configuration is not adopted, by reproducing with 100% of the color material, blurring and broken lines due to halftone processing can be suppressed, so that barcode reading accuracy can be improved.
According to the third aspect , compared to the case where this configuration is not adopted, the total amount of the color material such as toner can be reduced and the barcode reading accuracy can be improved.
According to the fourth aspect, the barcode reading accuracy can be further improved as compared with the case where this configuration is not adopted.
According to the fifth aspect , by selecting a preferable parameter table according to the type of barcode from a plurality of parameter tables in which presence or absence of execution of image processing is stored in advance, preferable image processing is performed according to the type of barcode. This can be realized and the recognition accuracy can be improved.
According to the sixth aspect , by selecting a preferable parameter table according to the quality of the barcode image from a plurality of parameter tables in which presence or absence of execution of image processing is stored in advance, for example, when an edge portion is lost due to scanning, etc. A preferable process according to the quality of the barcode image can be realized.
According to the seventh aspect of the present invention, it is possible to provide an image processing apparatus in which the reading accuracy is further improved in accordance with the characteristics of the image forming apparatus as compared with the case where this configuration is not adopted.
According to the eighth aspect of the present invention, it is possible to further improve the barcode reading accuracy and reduce the noise of the image data as compared with the case where this configuration is not adopted.
According to the ninth aspect , compared to the case where this configuration is not adopted, it is possible to maintain the barcode reading accuracy while maintaining the text data at a high resolution.
According to the tenth aspect, it is possible to realize good processing in the barcode area and other areas by a simple configuration of tag information.

According to the eleventh aspect , compared to the case where this configuration is not adopted, image data other than the barcode can be reduced in resolution while maintaining the barcode quality, the data amount of the entire image data is reduced, and the processing time is reduced. In addition, the computer can realize a function of maintaining the reading accuracy of the bar code character.
According to the twelfth aspect, it is possible to suppress the amount of the color material such as toner and to prevent the line reproduction from becoming thick.
According to the thirteenth aspect , by selecting a preferable parameter table according to the type and quality of the barcode from a plurality of parameter tables in which the presence or absence of execution of image processing is stored in advance, compared to a case where this configuration is not adopted, More preferable image processing according to the type and quality of the barcode can be realized.
According to the fourteenth aspect, it is possible to realize preferable image processing for the barcode area with a simple configuration called tag information, compared to a case where this configuration is not adopted.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[Embodiment 1]
FIG. 1 is a diagram showing an overall configuration of an image processing system to which the present embodiment is applied. Here, the client PC (personal computer) 1 which is a host computer that acquires input image data from an application and provides an electronic document (output image data) to an output destination, and information on the acquired electronic document (image data) are obtained. An image forming apparatus 2 that develops an image and prints it on a medium (paper), and an image reading apparatus (IIT) 3 that reads image data from a document are connected via a network 4.

  FIG. 2 is a functional block diagram showing this embodiment developed on the client PC 1 side. For example, an application 11 that generates image data including, for example, barcode information in response to an image output instruction from the user, and an image data acquisition unit 12 that acquires image data from the application 11 are provided. In addition, for example, an image data generation unit 10 that generates output image data to be output to the image forming apparatus 2 with respect to the image data acquired by the image data acquisition unit 12, and an image generated by the image data generation unit 10 An image data output unit 18 that outputs data to, for example, the image forming apparatus 2 via the network 4 is provided.

  The image data generation unit 10 includes a barcode detection unit 13 that detects the presence or absence of barcode information for each piece of image data acquired by the image data acquisition unit 12, and at least data that is determined to have barcode information. A TAG information adding unit 14 for adding TAG (tag) information is provided. Further, the image data generation unit 10 includes an image processing unit 15 that performs processing based on the TAG information added by the TAG information addition unit 14. The barcode detection unit 13 not only detects the presence / absence of barcode information, but also detects an area (first area) having barcode information and barcode information from the image data acquired by the image data acquisition unit 12. Another area (second area) that is not included is detected. In addition, the image processing unit 15 performs the first image processing on the first area detected by the barcode detection unit 13, and performs the second image processing different from the first image processing on the second area. Has been given.

  The image processing unit 15 includes a resolution conversion unit 16 that performs resolution conversion image processing in accordance with the acquired TAG information and resolution information, and image data that has undergone resolution conversion image processing by the resolution conversion unit 16 or image processing for resolution conversion. And an image compression unit 17 that performs compression processing on the image data that has not been subjected to. For example, the resolution conversion unit 16 does not perform resolution conversion image processing for an area having barcode information, and performs processing for reducing the resolution for an area that does not have barcode information. That is, an area having the barcode information (first area) and a predetermined area (second area) in the area not having the barcode information are divided and compared with the first resolution of the first area. Then, processing is performed such that the second resolution of the second region is lowered. In addition, for example, the image compression unit 17 performs processing by lossless compression without performing image processing for resolution conversion for the region having the barcode information (first region), and the region having no barcode information. For a predetermined area (second area), resolution conversion image processing is performed and compression processing is performed. For this second region, for example, lossy compression may be selected to increase the compression rate.

  FIG. 3 is a functional block diagram showing the present embodiment developed on the image forming apparatus 2 side. The image forming apparatus 2 acquires the image data generated by the client PC 1 or the image reading apparatus 3 and performs image processing for printing, and the image data processed by the image processing unit 20. And an image forming unit 21 that forms a visible image on a recording medium such as paper. The image forming unit 21 is configured as an output device such as an electrophotographic printer or an ink jet printer.

  The image processing unit 20 includes an image data acquisition unit 22 that acquires image data from the client PC 1 and the image reading device 3, and a TAG information detection / analysis unit 23 that detects and analyzes TAG information for each raster data, for example. It has. Further, for example, a barcode image correction unit 24 that performs image processing such as conversion to a barcode image corresponding to the printing direction based on barcode printing direction information held in the TAG information is provided. Further, for example, color for performing image processing for color conversion of R (red), G (green), and B (blue) image data into C (cyan), M (magenta), Y (yellow), and K (black). A conversion processing unit 25 and a screen processing unit 26 that performs screen processing in accordance with the print mode are provided.

  Here, in a system configuration in which processing using TAG information is not performed, the TAG information detection / analysis unit 23 does not have a function, and the barcode image correction unit 24 has a function of barcode detection processing. be able to. In the barcode detection processing function of the barcode image correction unit 24, for example, the type of barcode information, analysis of barcode data color, pattern matching, signal value analysis, and the like as described in Embodiments 2 to 5 described later. The signal quality level is determined using the. The barcode image correction unit 24 executes various processes as described later based on these barcode detection process results.

Further, when the barcode image is captured as an image by the scanning operation of the image reading device 3, the character / line is separated from the barcode image data (barcode data) by pictogram separation or edge detection. And the rest (pattern). Then, the barcode detection function of the barcode image correction unit 24 extracts whether or not the barcode information is in the separated character / edge region. At this time, the type of barcode (JAN / EAN etc.) is also specified by pattern matching.
The image reading device 3 can perform such extraction and identification processing, and can transmit the result information to the image forming device 2 together with the image data.
Thereafter, the image processing unit 20 cuts out a barcode area from the image data based on the result information, and performs signal conversion correction processing according to the barcode type in order to avoid deterioration of the barcode information. For example, if the barcode type is EAN, the image processing is executed so as to maintain a higher density than in the case of JAN.

  FIG. 4 is a functional block diagram showing the present embodiment developed on the image reading device 3 side. For example, the image reading device 3 scans a document placed on a platen glass and reads an image on the document, and an output image for outputting the image data read by the image data reading unit 31. An image data generation unit 30 that generates data and an image data output unit 38 that outputs the image data generated by the image data generation unit 30 are provided. The image data output unit 38 outputs image data to the client PC 1 and the image forming apparatus 2 via the network 4, for example. For example, when the image forming apparatus 2 and the image reading apparatus 3 are combined to form a multifunction device having functions such as a copying machine and a facsimile, the multifunction device has the image data output from the image data output unit 38. The data is input to the image forming apparatus 2 via a predetermined interface.

  The image data generation unit 30 includes a barcode detection unit 32 that detects the presence / absence of barcode information for each piece of data of the image data read by the image data reading unit 31, and at least data that is determined to have barcode information. A TAG information adding unit 33 for adding TAG (tag) information is provided. Further, the image data generation unit 30 includes an image processing unit 34 that performs processing based on the TAG information added by the TAG information addition unit 33. The bar code detection unit 32 not only detects the presence / absence of bar code information, but also detects an area having the bar code information (first area) and bar code information from the raster data read by the image data reading unit 31. Another area (second area) that is not included is detected. The image processing unit 34 performs the first image processing on the first region detected by the barcode detection unit 32, and performs the second image processing different from the first image processing on the second region. Has been given.

  The image processing unit 34 includes a resolution conversion unit 35 that performs image processing for resolution conversion according to the acquired TAG information and resolution information, and image data that has undergone resolution conversion image processing by the resolution conversion unit 35 or an image for resolution conversion. DF processing unit 36 that performs digital filter (DF) processing such as edge enhancement on image data that has not been processed, and correction processing such as enhancing the contrast between black and white on the barcode area. A signal correction processing unit 37. For example, the resolution conversion unit 35 performs image processing that converts (or maintains high resolution) an area that has barcode information to a high resolution, and converts an area that does not have barcode information to a low resolution. Process. That is, in the region having the barcode information (first region) and the predetermined region (second region) in the region not having the barcode information, compared to the first resolution of the first region, Processing is performed so that the second resolution of the area 2 is lowered. In addition, the DF processing unit 36 performs edge emphasis processing on an area having barcode information (first area) or an area that is text even if it has no barcode information. On the other hand, the DF processing unit 36 performs a smoothing process on a region that is an image in a region that does not have barcode information. Then, the signal correction processing unit 37 sets “R = G = B = 0” for the black portion of the barcode and the white portion of the barcode for the region having the barcode information (first region), for example. Is “R = G = B = 255”.

  FIG. 5 is a diagram for explaining an example of image data and image processing for resolution conversion. FIG. 5A shows an example of image data acquired by the image data acquisition unit 12 (see FIG. 2) and 22 (see FIG. 3) or read by the image data reading unit 31 (see FIG. 4). ing. FIGS. 5B and 5C are diagrams for explaining the state of the image data due to the difference in resolution.

  In the example shown in FIG. 5A, the acquired (read) image data includes an area having barcode information (first area, barcode area) and an area not having barcode information. doing. The areas that do not have bar code information include areas that have text information and areas for raster data such as photographs. The barcode area may be formed of raster data or a barcode may be formed using a command indicating a thin line.

  Consider a case in which a barcode image pasted at, for example, 600 dpi as shown in FIG. 5B is printed out as a chart with the barcode region pasted as raster data. When the barcode image is output with a reduced resolution of, for example, 200 dpi as shown in FIG. 5C, the density of the barcode image becomes a halftone density and the reading accuracy of the barcode image is lowered. Therefore, in the present embodiment, the region having the barcode information (first region) is processed with high resolution with an emphasis on barcode quality, and a predetermined region (the region having no barcode information) ( The second area (for example, an area of photographic data such as a natural image) is configured to perform image processing for resolution conversion with a reduced resolution in order to reduce the entire data amount and increase the throughput.

Next, processing of the printing system to which this exemplary embodiment is applied will be described.
FIG. 6 is a flowchart showing processing of the client PC 1 shown in the block diagram of FIG. Input image data from the application 11 is acquired by the image data acquisition unit 12 (step 101). With respect to the image data acquired by the image data acquisition unit 12, each raster data is analyzed by the barcode detection unit 13 of the image data generation unit 10 (step 102). Then, the presence or absence of bar code information is detected for each raster data (step 103). Detection of barcode information for raster data from the application 11 can be performed, for example, by comparing pixel values or performing simple pattern matching. For barcode information formed by other than raster data, such as barcode information formed by a command, a barcode area is detected by analyzing the command. If the barcode information is detected in step 103, the process proceeds to step 104. If the barcode information is not detected, step 104 is skipped and the process proceeds to step 105.

When the barcode information is detected by the barcode detection unit 13, the TAG information addition unit 14 adds the TAG information to the raster data from which the barcode information is detected (step 104). As in the example shown in FIG. 5A, when the barcode area indicated by the raster data exists, the TAG information is added to the raster data in the barcode area. The addition of the TAG information can be performed by activating a predetermined bit for each pixel or the like. However, it is also possible to specify a predetermined area instead of a pixel unit and perform it on an area basis.
In the flowchart shown in FIG. 6, TAG information is added for data with barcode information. However, different TAG information (with barcode information) is applied to raster data for which TAG information is not detected. (Different information) can be added. Furthermore, in addition to the presence / absence of a barcode, the TAG information can include barcode type information, barcode image quality information, printing direction, resolution information, and the like.

  The image data to which the TAG information is added is subjected to subsequent image processing based on the TAG information in the same client PC 1 as in the subsequent step 105. However, in addition to this mode, for example, in another apparatus of the image processing system shown in FIG. 1, for example, in the image forming apparatus 2 that has acquired the image data to which the TAG information is attached, the subsequent image processing is converted to the TAG information. There is a mode to be executed based on.

  Returning to FIG. Following step 104, the image processing unit 15 performs image processing suitable for the content of the TAG information on each raster data based on the added TAG information (step 105). Detailed contents in the image processing unit 15 will be described later. Thereafter, after the image processing unit 15 performs optimum image processing, output image data is generated (step 106), and the processing ends. The format of the output image generated in step 106 is, for example, a printer printing format when the above processing is performed in the printer driver as a part of the printing system, and a scan file format in the case of the scanning system. It becomes.

  Next, processing in the image processing unit 15 (processing in step 105 in FIG. 6) will be described. The resolution conversion unit 16 and the image compression unit 17 of the image processing unit 15 perform resolution conversion and image compression processing according to TAG information and resolution information, respectively. In the present embodiment, image processing for resolution conversion and image compression is performed as the image processing. However, the present invention is not limited to this.

  The resolution conversion unit 16 of the image processing unit 15 acquires TAG information for each raster data (or for each pixel) for each raster data of the internal data from the TAG information adding unit 14 (step 111). And it is judged whether it has TAG information (step 112). If there is TAG information, the image processing for resolution conversion is omitted, and the process proceeds to the compression processing in step 116 executed by the image compression unit 17. If there is no TAG information, resolution conversion image processing is performed to reduce the amount of data shown in steps 113 to 115. In this resolution conversion image processing, first, resolution information for each raster data is acquired (step 113). Then, the acquired resolution is compared with a predetermined threshold resolution (200 dpi here). If it is not equal to or greater than the threshold (threshold resolution), the image processing for resolution conversion is omitted, and the process proceeds to the compression processing in step 116. If it is equal to or greater than the threshold, image processing for resolution conversion is performed to a resolution of the threshold (here, 200 dpi) (step 115). The image data that has undergone resolution conversion image processing within the threshold is subjected to lossless compression processing, for example, in the same manner as barcode image data (step 116). Of course, irreversible compression may be used instead of lossless compression.

  It should be noted that the acquisition of resolution information in step 113 may be performed when image data is stored in a file, or may be calculated from the number of pixels and coordinate data. Further, in the present embodiment, the resolution information is acquired by the resolution conversion unit 16, but information acquisition may be performed in the preceding process as part of the TAG information. As an image processing method for resolution conversion, for example, a projection method or the like can be used, and any method can be adopted as the method. Further, the raster data of the barcode is transmitted to the output device with a high resolution without any loss of information. On the other hand, natural images that do not impair image quality even when the resolution is reduced can be subjected to resolution conversion image processing to create print data, and the total data amount is reduced and transmitted to the output device.

  FIGS. 7A and 7B are diagrams for explaining processing of the image processing unit 20 on the image forming apparatus 2 side illustrated in FIG. 3. FIG. 7A is a flowchart showing the processing of the image processing unit 20, and FIG. 7B is a table detailing the processing contents of the image processing unit 20. The image data acquisition unit 22 of the image processing unit 20 acquires image data from the client PC 1 or the image reading device 3 via the network 4 (step 201). The TAG information detection / analysis unit 23 detects and analyzes the TAG information for each raster data of the acquired image data (step 202). Here, the presence / absence of barcode information is determined by the TAG information detection / analysis unit 23 (step 203). For an area without bar code information (raster data without bar code information), the process proceeds to step 208, where the color conversion processing unit 25 performs image processing of RGB → CMYK color conversion, and the gray axis is the process K. Color conversion image processing is performed with the color conversion parameters (step 208). In this process K, the so-called UCR (Under Color Removal) is not 100%, and a CMY color material (toner or the like) other than the K color material is also used to express a gray color.

  If it is determined in step 203 that there is barcode information, the printing direction of the barcode (barcode line) is acquired (step 204). The barcode line printing direction includes a direction parallel to a main scanning direction of the image forming unit 21 that forms an image and a direction perpendicular to the main scanning direction. The TAG information detected by the TAG information detection / analysis unit 23 may include information on the printing direction of the barcode line. The barcode line printing direction can be determined, for example, by performing simple pattern matching when the barcode detection unit 13 shown in FIG. 2 detects the presence or absence of a barcode. Or you may determine simply from the aspect ratio of raster data. When the information on the printing direction of the barcode line is included in the TAG information, the printing direction of the barcode line is added as the TAG information together with the information on the presence / absence of the TAG by the TAG information adding unit 14 shown in FIG. .

  In the image processing unit 20 shown in FIG. 3, for example, in the TAG information detection / analysis unit 23, whether the barcode line printing direction is perpendicular (horizontal) to the main scanning direction (exposure scanning direction) of the image forming unit 21. Is determined (step 205). If the individual lines of the barcode are lateral (for example, vertical) with respect to the main scanning direction, the barcode image correction unit 24 adjusts the line width (step 206). If it is not horizontal (vertical), step 206 is omitted and the process proceeds to step 207. For example, when the image forming unit 21 is a printing apparatus using an electrophotographic method, it is known that even when data having the same line width is drawn with vertical and horizontal lines, the printed line widths are different. . For example, in the horizontal (perpendicular) line with respect to the main scanning direction, the dots are continuous in the sub-scanning direction, and when dots are sequentially formed in the main scanning direction, the print dots are isolated. In general, the line width may be smaller than a line parallel to the line. In the present embodiment, the barcode image correction unit 24 corrects the black and white dots of the barcode image according to the printing direction. More specifically, the characteristics of the image forming unit 21 are captured. For example, when the image forming unit 21 adopts an electrophotographic method, the image data is corrected so as to be thicker than the target line width of the barcode. To do. As a result, even when a line that is transverse (perpendicular) to the main scanning direction is output narrowly, the target line width is approached. When the printing direction is parallel to the main scanning direction, the line width is not adjusted.

  Thereafter, the color conversion processing unit 25 performs image processing for RGB → CMYK color conversion. At this time, the raster data with barcode information (barcode image) in step 203 is subjected to image processing for color conversion with the K-axis of the gray axis (step 207). If single K reproduction is performed for all photographic data such as natural images, the reproduction of the low brightness part appears to be white and the image quality is degraded. Therefore, normally, raster data is processed by the process K on the K axis as an image object. When the process K is performed, the color reproduction range is expanded to a lower lightness and the quality is higher than in the case of processing with the K single color. On the other hand, since the amount of color material (for example, the amount of toner) increases, the line reproduction becomes thick and the barcode reading accuracy decreases. In the present embodiment, switching between K single color and process K is performed depending on whether or not the area is barcode information. After such color conversion processing, the screen processing unit 26 performs screen processing in accordance with the print mode (step 209), and outputs image data to the image forming unit 21.

  FIG. 7B shows the processing of FIG. 7A in a table. First, the TAG information includes the presence / absence of a barcode. When the barcode is present, information on the printing direction of the barcode (whether it is parallel or perpendicular to the main scanning direction) is included. The processing content of the image processing unit 20 differs depending on the TAG information. In the barcode image correction performed by the barcode image correction unit 24, the line width is adjusted when a barcode is present and the barcode printing direction is perpendicular to the main scanning direction. In the color conversion image processing performed by the color conversion processing unit 25, the gray axis is the process K when there is no barcode, and when there is a barcode, the gray axis is single K (UCR 100%). Image processing is performed. UCR 100% is set by, for example, a direct look-up table (DLUT), and by making bar code data into a black reproduction output of 100% density, unlike the halftone area, it is caused by interference with the device screen of the image forming unit 21. Elimination and fading are avoided to improve recognition accuracy.

  8A and 8B are diagrams for explaining the processing on the image reading apparatus 3 side shown in FIG. FIG. 8A is a flowchart showing the processing of the image reading device 3, and FIG. 8B is a table detailing the processing contents performed in the image data generating unit 30 of the image reading device 3. The image data reading unit 31 of the image reading device 3 reads the image data with a fixed resolution of, for example, a scan resolution of 600 dpi (step 301). The barcode detection unit 32 detects an object of barcode data, and also detects each object of image and text (step 302). This object detection is performed by pattern detection to determine whether there is a barcode object in the character / edge area by separating it into a character / line drawing and other (picture = image) by pictogram separation processing and edge detection processing (not shown). Etc. For example, the barcode position and type are detected by pattern matching, and only the barcode area is automatically cut out from the scan image by image cut-out processing.

  Next, the TAG information adding unit 33 adds TAG information to each object (step 303). Subsequently, the resolution conversion unit 35, the DF (digital filter) processing unit 36, and the signal correction processing unit 37 of the image processing unit 34 perform image processing for resolution conversion, filter processing, and image processing for signal correction, respectively. The details of the image processing for each TAG information are, for example, as shown in FIG. Image, text, and barcode objects are determined as TAG information, and resolution conversion image processing, digital filter processing, and signal correction processing shown in the table are performed according to the objects. 8A, the TAG information adding unit 33 determines whether or not the predetermined object area is a bar code (step 304). If it is not a bar code, is the predetermined object area an image? It is determined whether the text (step 305). Based on these determinations, the contents of resolution conversion image processing, digital filter processing, and signal correction processing are determined, and each processing is executed.

If it is determined in step 305 that the data is image data, the resolution conversion unit 35 reduces the resolution to 200 dpi (step 306), and the DF processing unit 36 performs smoothing processing (step 307). If it is determined in step 305 that the data is text data, the resolution conversion unit 35 converts it to 600 dpi (step 308), and the DF processing unit 36 performs edge enhancement processing (step 309). If it is determined in step 304 that it is a barcode, the resolution conversion unit 35 converts it to 600 dpi (step 310), and the DF processing unit 36 performs edge enhancement processing (step 311). Further, the signal correction processing unit 37 performs signal correction processing (step 312). This signal correction process is performed on the barcode object. For example, a pixel value equal to or greater than a predetermined threshold value is set to R = G = B = 0 (black), and the other pixel values are set to R = G = B = 255 ( White). In the DF processing unit 36, the sharpness of the black line in the barcode area is optimized to improve the recognition rate, and the area-specific adaptive filter process for performing processing with different characteristics for each object is performed.
After executing the processing as described above, image data is output from the image data output unit 38 (step 313), and a series of processing ends.

[Embodiment 2]
In the second embodiment, bar code characteristics (for example, bar code type and bar code image quality) are analyzed from the acquired image data, and various types of image processing are performed using the analysis results.
FIG. 9 is a flowchart showing the processing of the second embodiment performed in the image forming apparatus 2, for example. FIGS. 10A and 10B are diagrams illustrating an example of a process control data table and an example of a barcode image. 10A, for example, as a process control data table stored and used in the barcode image correction unit 24 shown in FIG. 3, for example, a barcode type table 51 for determining processing according to the type of barcode, A parameter set table 52 for determining a preferable parameter from the degree of deterioration of the value is shown. In FIG. 10B, as the barcode image in the acquired image data, the narrow barcode (NB) width is narrow and faithful barcode image 1 and the barcode image 2 in which signal deterioration is observed at the edge portion of the bar. Is shown.

  A narrow bar (NB), which is a thin bar, is used for the bar code, and has a NB width required for reading the bar code. For example, since a bar code type with a narrow NB width prints many bars in a predetermined space, line reproduction is required very strictly. On the other hand, when the NB width is large, the barcode size is large and the reading range is large, so even if the line reproduction is thick, it is acceptable if the code can be identified. For bar code types with a narrow NB width, output devices with high line reproduction performance such as laser printers, thermal transfer printers, and printing machines are used. For bar code types with a large NB width, output devices such as dot impact printers and ink jet printers that may have low line reproduction performance are used. Due to the characteristics of the barcode image, there is a difference in the line reproduction performance required according to the type of barcode. Therefore, by identifying the line reproduction performance, it is possible to simplify the image processing, and there is a case where processing other than the barcode and the barcode need not be divided. It is also effective to switch the processing parameters appropriately according to the quality of the barcode information part added to the electronic information.

  As shown in FIG. 9, in the second embodiment, for example, after the image data is read by the image data acquisition unit 22 shown in FIG. 3 (step 401), the barcode data correction unit 24 analyzes the image data. (Step 402). Then, it is determined whether or not barcode data exists (step 403). If not, normal image processing (for example, compression processing, color conversion image processing, filter processing, gradation correction processing) corresponding to the selected print mode is executed (step 404), and the processing ends. If there is barcode data in step 403, first, the type of barcode is analyzed (step 405). Then, a predetermined image processing set is selected from the barcode type table 51 as shown in FIG.

For example, the barcode type as shown in FIG. 10B is a type in which NB width is narrow and faithful line reproduction is strictly required from the result of pattern matching. At this time, “image processing set 1” is selected from the barcode type table 51 according to the barcode type determined in the barcode type analysis (step 405) of the barcode image correction unit 24 (step 406). . That is, since both the barcode image 1 and the barcode image 2 shown in FIG. 10B are the same barcode type and the fine line fidelity with a narrow NB width is important, the “image processing set 1” is Selected. As the “image processing set 1”, for example, it is determined that digital filter processing (DF), tone correction processing (TRC), compression processing (Comp), and output device control processing (IOT) are necessary.
For example, the following settings are made to perform all image processing correction necessary for the barcode.
Table data: 1111
Contents: DF ON,
TRC ON,
Comp OFF,
IOT ON

Next, the barcode image correction unit 24 analyzes the quality of the barcode image (step 407). Then, a predetermined parameter set is selected from the parameter set table 52 as shown in FIG. 10A (step 408). That is, in the image quality determination of the barcode image correction unit 24, the signal value is compared with the pattern, and an appropriate “parameter set” is determined based on the degree of deterioration of the signal value from the parameter table in which predetermined parameters are stored in advance. select. For example, the barcode image 1 shown in FIG. 10B is an ideal image signal value. For example, “parameter set 1” is selected.
Table data: 01120001
Content: “01” DF parameter Index no.1
“12” TRC parameter Index no.12
“00” Comp OFF
“01” IOT barcode control

In the case of the barcode image 2 shown in FIG. 10B, since signal deterioration is observed at the edge portion of the bar, the DF parameter for signal correction is selected according to the deterioration amount. In this case, for example, “parameter set 5” is selected.
Table data: 05120001
Content: “05” DF parameter Index no.5
“12” TRC parameter Index no.12
“00” Comp OFF
“01” IOT Barcode Control As described above, in the image processing unit 20, each table data is selected from the result of barcode detection by the barcode image correcting unit 24, and “image processing set” and “ The barcode image is processed using the Index value of the “parameter set”.

[Embodiment 3]
In the third embodiment, an example in which suitable filter processing is performed according to the amount of edge rounding will be described.
FIGS. 11A to 11C are diagrams for explaining an example of signal correction using a digital filter. FIG. 11A shows an example of an original barcode image, and FIG. 11B shows an example of so-called scan data read and pasted by a scanner (image reading device 3). FIG. 11C shows an example of a barcode image after digital filter processing is performed according to the present embodiment. The right side of each figure shows the state of the image, with the horizontal axis representing pixels and the vertical axis representing signal values.

  When the barcode data is pasted as scan data, the edge of the original barcode image shown in FIG. 11A deteriorates, and the edge signal value of the barcode as shown in FIG. Will collapse without stabilizing. Therefore, by selecting a digital filter having characteristics that enable restoration processing of the signal degradation level, and processing using the digital filter, a bar with improved edge degradation as shown in FIG. Code data can be obtained. At this time, as an index for estimating the barcode data to be restored, the barcode type detected in the signal value analysis by pattern matching and the level analysis result of the analyzed signal quality are used (see Embodiment 2). A suitable digital filter parameter is selected by referring to these.

[Embodiment 4]
The barcode also includes a color barcode. In addition to the barcode detection by pattern matching or the like, the barcode color information is detected from the color signal value by the barcode detection function by the barcode image correction unit 24. The barcode information image is subjected to color conversion image processing for reproduction with a single color material of 100% or a combination of two color materials of 200%. For example, red is 100% yellow + 100% magenta, green is 100% yellow + 100% cyan, blue is 100% magenta + 100% cyan, or special color toner such as red / green / blue is loaded. The bar code image correction unit 24 corrects the image signal value so that each color material is reproduced with 100%. In other words, in the case of a printer having YMCK toner other than K single color material, for example, C100%, M100%, R (Y100% + M100%), G (Y100% + C100%), B (M100% + C100%) It is conceivable to reproduce the code, and in the case of a multi-color (more than 5 colors) printer such as YMCK + spot color, in addition to the above, for example, 100% spot color is reproduced. As a result, the barcode image disappears from the halftone density, and the quality of the image output is prevented from deteriorating due to interference problems such as blurring or broken lines due to screen processing.
In addition, if it is specified in a light color other than that, it is automatically replaced with 100% black (K) with high recognition accuracy, so that the contrast with the background portion can be secured and the blurring etc. is eliminated. To improve the recognition accuracy. Similarly, it is also effective to perform processing such as replacing the color barcode with 100% black (K) to improve the recognition accuracy.

Thus, image processing for printing using a single color material is performed here. As this single color material, the above-described K (black) single color material is most frequently used, but depending on the type of barcode, for example, a red single color material can be used.
Furthermore, it is preferable to perform image processing so that the background portion of the barcode information is printed without using any color material in the region where the barcode image is formed.

[Embodiment 5]
In the control of the image forming unit 21 shown in FIG. 3, for example, when there is control dedicated to barcodes, such as when correction control is required in the output device, the detection is detected from the image processing unit 20 to the image forming unit 21 side. Notify the type of bar code. In the image processing unit 20, for example, an environmental sensor (not shown) is arranged in the apparatus, and the output device control parameter is corrected using the value of the environmental variation correction obtained from the environmental sensor. Then, the coefficient set in advance from the barcode information notified from the image processing unit 20 is processed into the output device control parameter, and the image processing unit 20 executes control suitable for barcode output.

Also, for example, when the barcode control instruction signal is output from the image processing unit 20 with the configuration shown in the second embodiment, the NB width is narrow and faithful line reproduction is strictly required. Since it is a bar code type, the image forming unit 21 temporarily goes down. As the cycle down, when the image forming unit 21 adopts an electrophotographic system, for example, in an image forming process (not shown), for example, the amount of light from the exposure device that exposes the photosensitive member is suppressed (reduced), and the developing performance is deteriorated. By reducing the developing power, for example, even with the same image signal value, the line is reproduced thinner than usual. However, reducing the amount of light significantly reduces output reproduction other than the barcode such as highlight reproduction performance reduction and gradation performance reduction due to density reduction. For this purpose, the image processing unit 20 performs dedicated TRC processing in advance. Depending on the type of bar code, if it is not possible to cope with exposure control alone, it is also preferable to finely adjust the developing bias applied to the developing device by lowering it. In particular, this fine adjustment is effective in the case of a code pattern finer than a conventional barcode such as a QR code.
In the case of a bar code type that does not require the NB-wide line reproducibility so severely, it is possible to adopt normal control as it is instead of bar code control. The control of the unit 21 is suitably controlled.

1 is a diagram illustrating an overall configuration of an image processing system to which the exemplary embodiment is applied. It is the functional block diagram which showed the example of this Embodiment expand | deployed by the client PC side. FIG. 2 is a functional block diagram showing an embodiment of the present invention developed on the image forming apparatus side. It is a functional block diagram showing an example of the present embodiment developed on the image reading apparatus side. (A)-(c) is a figure for demonstrating the example of image data and the image process of resolution conversion. It is a flowchart which shows the process of the client PC shown by the block diagram of FIG. (A), (b) is a figure for demonstrating the process of the image process part by the side of the image forming apparatus shown in FIG. (A), (b) is a figure for demonstrating the process by the side of the image reading apparatus shown in FIG. For example, a flowchart illustrating processing of Embodiment 2 performed in the image forming apparatus. (A), (b) is the figure which showed the example of the data table for process control, and the example of a barcode image. (A)-(c) is a figure for demonstrating the example of the signal correction by a digital filter.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Client PC (personal computer), 2 ... Image forming apparatus, 3 ... Image reading apparatus (IIT), 10 ... Image data generation part, 11 ... Application, 12 ... Image data acquisition part, 13 ... Barcode detection part, 14 TAG information adding unit, 15 ... image processing unit, 16 ... resolution conversion unit, 17 ... image compression unit, 18 ... image data output unit, 20 ... image processing unit, 21 ... image forming unit, 22 ... image data acquisition unit, 23 ... TAG information detection / analysis unit, 24 ... Barcode image correction unit, 25 ... Color conversion processing unit, 26 ... Screen processing unit, 30 ... Image data generation unit, 31 ... Image data reading unit, 32 ... Barcode detection unit 33 ... TAG information adding unit 34 ... Image processing unit 35 ... Resolution converting unit 36 ... DF processing unit 37 ... Signal correction processing unit 51 ... Barcode type table 52 ... parameter set table

Claims (14)

An acquisition unit for acquiring image data;
A detection unit for detecting a first region having barcode information and a second region having no barcode information from the image data acquired by the acquisition unit;
An image processing unit that performs first image processing on the first region detected by the detection unit, and performs second image processing different from the first image processing on the second region;
The first image processing performed by the image processing unit performs resolution conversion image processing for increasing the resolution of the first area, thereby performing image data constituting the first area. Let the resolution be the first resolution ,
The second image processing performed by the image processing unit performs resolution conversion image processing that lowers the resolution on the second area, thereby performing image data constituting the second area. An image processing apparatus characterized in that the resolution is a second resolution lower than the first resolution . The image processing unit performs image processing of color conversion for reproducing the barcode information image in the first area with a single color material of 100% or a combination of two color materials of 200%. The image processing apparatus according to claim 1 . Claim wherein the image processing unit so as to print using the K (black) alone colorant, characterized in that it performs image processing of the color conversion on the image of the bar code information in the first region The image processing apparatus according to 1 or 2 . The image processing unit according to any one of claims 1 to 3, characterized in that performing image processing to print without also using the bar code information either colorant background portion in said first region Image processing apparatus. A barcode type detection unit for detecting a barcode type for the barcode information;
The bar code type detection unit detects the presence or absence of execution of digital filter processing, gradation correction processing, compression processing, and output device processing as predetermined parameters. 5. The image processing apparatus according to claim 1, wherein a preferable parameter table is selected in accordance with a type of the barcode and the first image processing is performed. The barcode information further comprises a barcode quality detection unit that detects the quality of the barcode image by analyzing the signal value of the barcode information,
The bar code quality detection unit detects the presence or absence of execution of digital filter processing, gradation correction processing, compression processing, and output device processing as predetermined parameters. 6. The image processing apparatus according to claim 1, wherein a preferable parameter table is selected in accordance with the quality of the barcode image, and the first image processing is performed. The image processing unit detects the orientation of the barcode forming the barcode information, and if the individual lines of the barcode are lateral to the main scanning direction of image formation, the line width is increased. The image processing apparatus according to claim 1, wherein the image data is corrected. The detection unit detects an area having image data as the second area,
In the first image processing performed by the image processing unit, the bar code is set after the resolution of image data constituting the first area is set to the first resolution with respect to the first area. Perform edge enhancement processing to clarify the contour of the image portion in the information, and signal correction processing to increase the contrast between the image portion and the background portion in the barcode information,
In the second image processing performed by the image processing unit, the image data after the resolution of the image data constituting the second area is set to the second resolution with respect to the second area. The image processing apparatus according to claim 1, wherein smoothing processing for reducing noise is performed. The detection unit further detects a region having text data from the image data acquired by the acquisition unit as a third region,
The image processing unit performs resolution conversion image processing on the third area detected by the detection unit, thereby reducing the resolution of the image data constituting the third area from the second resolution. 9. The image processing apparatus according to claim 8 , wherein after the third resolution is set to be higher, third image processing is performed to perform edge enhancement processing for clarifying a contour of a text portion in the text data. A tag information adding unit for adding tag information indicating the presence of the barcode information to a barcode region unit or pixel unit of image data constituting the first region detected by the detection unit;
The image processing apparatus according to claim 1, wherein the image processing unit performs the first image processing on the first area based on the tag information. To the computer that performs image processing,
A function to acquire image data;
A function of detecting, from the acquired image data, a first area having barcode information and a second area having no barcode information;
A function of performing first image processing on the detected first region and performing second image processing different from the first image processing on the detected second region;
In the first image processing, the resolution of image data constituting the first area is set to the first resolution by performing resolution conversion image processing for increasing the resolution on the first area .
In the second image processing, the resolution of the image data constituting the second area is made higher than that of the first resolution by performing resolution conversion image processing for lowering the resolution on the second area. A program having a lower second resolution . 12. The program according to claim 11 , wherein the first image processing performs image processing for printing the barcode information image in the first area using a single color material. The computer further realizes a function of detecting a barcode type and / or quality of a barcode image with respect to the barcode information,
In the first image processing, the type of the bar code detected from a plurality of parameter tables in which presence / absence of execution of digital filter processing, gradation correction processing, compression processing, and output device processing is stored in advance as predetermined parameters. 13. The program according to claim 11 , wherein a preferable parameter table is selected and image processing is performed in accordance with quality of the barcode image. The computer further realizes a function of adding tag information indicating the presence of the barcode information in a barcode area unit or pixel unit of the detected image data constituting the first area,
The program according to claim 11 , wherein the first image processing performs the first image processing on the first area based on the tag information.

Images