JP4595787B2 - Printing device, image processing device - Google Patents

Description

  The present invention relates to a printing apparatus, and more particularly to a printing apparatus that can interpret a plurality of types of page description languages.

  As described in the prior art of Patent Document 1, in a color printing apparatus, image data composed of three color components (RGB format) of red, green, and blue is used for printing cyan, magenta, yellow, and black. The color component (CMYK format) is converted.

  FIG. 4 is a block diagram showing a conventional configuration of an image processing apparatus 200 that performs image processing such as color conversion processing and the vicinity thereof.

  As shown in this figure, RGB format image data 221 generated by the CPU 210 is stored in the main memory 220. The read DMA circuit 201 of the image processing apparatus 200 reads this image data 221 and sends it to the color conversion circuit 202.

  The color conversion circuit 202 performs color conversion from the RGB format to the CMYK format. Then, each color of CMYK is compressed by the compression circuit 203. The compressed data is written into the main memory 220 by the Write DMA circuit 204 and stored as compressed data 222. Then, the data is DMA transferred to the screen processing circuit 250, subjected to decompression processing and screen processing, and then sent to the print engine 230 to execute printing.

  In this way, the generated image data 221 is subjected to processing such as color conversion and compression by the image processing apparatus 200, but generally these processing are performed at a high speed because they are performed in hardware.

Japanese Patent Laid-Open No. 4-171582

  The image data 221 in the RGB format is generated by the CPU 210 interpreting the print data described in the page description language and expanding it into bitmap data.

  Here, when the CPU 210 can interpret a plurality of types of page description languages, image data in RGB format is generated according to an algorithm defined in each page description language.

  However, the format of the generated RGB format image data may differ depending on the specification of the page description language.

  For example, image data generated from a certain page description language is expressed by a value from 0 to 255 in the order of RGB in the order of RGB from low to high, while from another page description language. The generated image data is expressed not in the RGB order but in the reverse BGR arrangement order, or the image data generated from another page description language is 0 in the direction from the lower density to the higher density. This is the case when it is expressed by the opposite value of 255-0 instead of ~ 255.

  As described above, since the image processing apparatus 200 processes image data having different formats, it is necessary to convert the data into a unified format before inputting the image data into the image processing apparatus 200. Since conversion processing to this format is performed by software by the CPU 210, much processing time is required.

  An object of the present invention is to improve the format conversion processing speed of image data in a printing apparatus capable of processing a plurality of types of page description languages.

In order to solve the above problems, according to the present invention,
Interpreting means capable of interpreting a plurality of types of page description languages and generating image data in RGB format having different formats depending on the page description language;
Storage means for storing image data generated by the interpretation means;
An image processing unit that reads image data stored in the storage unit and performs color conversion processing;
The image processing unit performs format conversion on the read image data according to the type of page description language that is the source of the image data, and then performs the color conversion processing. An apparatus is provided.

  In the present invention, since the image processing means of the format conversion circuit performs format conversion according to the type of page description language, the format conversion processing speed of image data is improved in a printing apparatus capable of processing a plurality of types of page description language. Can be made.

Here, the interpretation unit performs setting for the image processing unit according to the page description language that is the basis of the generated image data,
The image processing means can perform format conversion according to the setting.

  The format conversion performed by the image processing means can include a process for changing the arrangement of RGB constituting the image data, or a process for inverting each value of RGB constituting the image data.

In order to solve the above problems, according to the present invention,
An image processing apparatus that reads image data generated based on a page description language and performs color conversion processing,
Provided is an image processing apparatus that performs color conversion on the read image data after performing format conversion according to the type of page description language that is the source of the image data. .

  Embodiments of the present invention will be described with reference to the drawings.

  In this embodiment, a controller unit of a color printer will be described as an example of a printing apparatus. However, the present invention can be widely applied to printing apparatuses that perform printing by interpreting a page description language. Further, the printing apparatus is not limited to a single apparatus such as a printer, a facsimile apparatus, or a multifunction machine, and may be configured by a plurality of apparatuses such as a printer and a host computer.

  FIG. 1 is a block diagram showing a configuration of an image processing apparatus 100 provided on a controller board of a color printer and its periphery.

  The image processing apparatus 100 has functions for performing color conversion, compression processing, and the like of image data, and can be realized as, for example, one of ASIC (Application Specific Integrated Circuit) modules.

  As shown in the figure, a CPU 110 is provided on the controller board, and a page description language interpretation unit 111 is virtually configured in the CPU 110. The page description language interpretation unit 111 performs processing for expanding print data described in a page description language into image data in a bitmap format. Here, the page description language interpretation unit 111 can interpret a plurality of types of page description languages. The page description language interpretation unit 111 can be configured by the CPU 110 executing a program recorded in a ROM (not shown) or the like.

  FIG. 2 is a diagram showing examples of page description languages that can be interpreted by the page description language interpreter 111 and examples of the output results.

  As shown in the figure, the page description language interpretation unit 111 includes a page description language A interpretation unit 111a, a page description language B interpretation unit 111b, and a page description language C interpretation unit 111c. The description language B and the page description language C can be interpreted, and image data based on the page description language is generated.

  However, each page description language has its own specifications. For this reason, the image data generated by the algorithm according to the specification of the page description language may have a different format for each page description language. In this example, it is assumed that image data in the following format is generated.

  That is, the image data generated by the page description language A interpreter 111a according to the specification of the page description language A is expressed by a value from 0 to 255 in the order of RGB in the order from the lowest density to the higher density. .

  The image data generated by the page description language B interpreter 111b according to the specification of the page description language B is the page description in the order of BGR from the lower density to the higher density in the reverse BGR arrangement order of the page description language A. As with language A, it is represented by a value from 0 to 255.

  The image data generated by the page description language C interpreter 111c according to the specification of the page description language C is the same RGB order as the page description language A, and the page description language A in the direction from the lower density to the higher density. On the contrary, it is expressed by a value of 255-0.

  Returning to FIG. 1, image data 121 in the RGB format generated by the page description language interpretation unit 111 of the CPU 110 is stored in the main memory 120.

  The image processing apparatus 100 includes a ReadDMA circuit 101 and a format conversion circuit 106. The ReadDMA circuit 101 reads the image data 121 generated from the main memory 120 and transfers it to the format conversion circuit 106.

  Here, the image data 121 is recorded in the RGB format, but as described above, the format differs depending on the page description language. The format conversion circuit 106 performs processing for converting different formats into a unified format. Here, it is assumed that the format is a page description language A format.

  For this reason, the page description language interpretation unit 111 of the CPU 110 sets the mode in the format conversion circuit 106 according to which page description language the image data to be processed is in. Thereby, the format conversion circuit 106 can determine what format conversion should be performed.

  FIG. 3 is a block diagram illustrating an example of the configuration of the format conversion circuit 106. As shown in the figure, the format conversion circuit 106 includes a selector circuit and an inverting circuit, and each circuit can be turned on / off by mode setting from the page description language interpretation unit 111 of the CPU 110. It has become.

  Here, the selector circuit is a circuit for exchanging R and B, and converts the format of the image data generated based on the page description language B into the format of the image data generated based on the page description language A. It is a circuit for doing.

  The inversion circuit is a circuit for inverting 0 to 255 to 255 to 0 for each of RGB, and the format of the image data generated based on the page description language C is generated based on the page description language A. It is a circuit for converting to a format of image data.

  By switching on / off of these circuits, the image data output from the format conversion circuit is represented by a value from 0 to 255 in the order of RGB in the order from low to high density. Therefore, the format of the image data generated based on the page description language A is unified.

  Of course, the configuration of the format conversion circuit 106 shown in FIG. 3 is an example, and the configuration of the format conversion circuit 106 corresponds to the format of the image data to be converted.

  As shown in FIG. 1, in addition to the format conversion circuit 106 and the like, the image processing apparatus 100 includes a color conversion circuit 102 that performs color conversion processing from RGB format to CMYK format, and a compression circuit 103 that performs compression processing for each color of CMYK. A Write DMA circuit 104 that performs DMA transfer to the main memory 120 is provided.

  The RGB format image data whose format is unified by the format conversion circuit 106 is sent to the color conversion circuit 102, and color conversion from the RGB format to the CMYK format is performed. Then, each color of CMYK is compressed by the compression circuit 103.

  The compressed data is written into the main memory 120 by the Write DMA circuit 104 and stored as compressed data 122. Then, the data is DMA-transferred to the screen processing circuit 150, subjected to decompression processing and screen processing, and then sent to the print engine 130 to execute printing.

  As shown in the above embodiments, since the format conversion circuit is incorporated in the image processing apparatus in the present invention, the format conversion processing speed of image data is improved in a printing apparatus capable of processing a plurality of types of page description languages. be able to.

1 is a block diagram illustrating an image processing apparatus according to an embodiment and a configuration around the image processing apparatus. The block diagram which shows the structure of a format switching circuit. The figure which shows an example of a structure of a format conversion circuit. 1 is a block diagram showing a conventional image processing apparatus and its peripheral configuration.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Image processing apparatus, 101 ... ReadDMA circuit, 102 ... Color conversion circuit, 103 ... Compression circuit, 104 ... WriteDMA circuit, 106 ... Format conversion circuit, 110 ... Image processing apparatus, 111 ... CPU, 120 ... Main memory, 130 ... Print engine 150 ... Screen processing circuit 200 ... Image processing device 201 ... ReadDMA circuit 202 ... Color conversion circuit 203 ... Compression circuit 204 ... WriteDMA circuit 210 ... CPU 220 ... Main memory 230 ... Print engine 250: Screen processing circuit

Claims (4)

Interpreting means capable of interpreting a plurality of types of page description languages and generating image data in RGB format having different formats depending on the page description language;
Storage means for storing image data generated by the interpretation means;
An image processing unit that reads image data stored in the storage unit and performs color conversion processing;
The image processing means includes a selector circuit and an inverting circuit, and performs format conversion on the read image data according to the type of page description language that is the source of the image data, and A circuit that performs color conversion processing ,
The interpreting unit performs setting for the image processing unit according to a page description language from which the generated image data is based, and turns on the selector circuit and the inversion circuit according to the format of the generated image data. , Switch off,
The image processing means performs format conversion according to the setting by the interpretation means,
When the selector circuit is turned on by the interpretation unit, the selector circuit rearranges RGB constituting the read image data,
When the inversion circuit is turned on by the interpretation means, it inverts the RGB values constituting the read image data.
A printing apparatus characterized by that. The printing apparatus according to claim 1,
The printing apparatus according to claim 1, wherein the format conversion performed by the image processing means includes a process of changing an arrangement of RGB constituting the image data. The printing apparatus according to claim 1,
The printing apparatus according to claim 1, wherein the format conversion performed by the image processing means includes a process of inverting RGB values constituting image data. An image processing apparatus that reads image data generated based on a page description language and performs color conversion processing,
Image processing means for performing the color conversion processing on the read image data after performing format conversion according to the type of page description language that is the source of the image data ;
The image processing means, when set according to the page description language, performs format conversion according to the setting, and includes a selector circuit and an inverting circuit.
When the selector circuit is turned on, it rearranges RGB constituting the read image data,
When the inversion circuit is turned on, each of the RGB values constituting the read image data is inverted.
An image processing apparatus.

Images