JP4400709B2 - Image processing apparatus and image processing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention interprets an input drawing command to generate intermediate code image data, renders the intermediate code image data to create a bitmap image, and further corrects the bitmap image based on the attribute information. The present invention relates to an image processing technique for outputting a final bitmap image to a printing device or the like.
[0002]
[Prior art]
An image processing apparatus that has received a print command from a host processing device such as a personal computer receives a drawing command that is actual print information, sequentially interprets it, and creates and outputs a bitmap image. In this process, when the image processing apparatus holds a page buffer, the interpreted bitmap image is directly written in the page buffer (rendering process) and output in units of pages. In addition, since the page buffer requires a large storage capacity, in many cases, a page buffer (band buffer) obtained by dividing one page into a plurality of pages is held instead of the page buffer. In such a case, once converted into band-based intermediate code image data, after interpretation of all drawing commands and generation of intermediate code image data, the intermediate code image data is interpreted in band units, and a bitmap image is converted. Performs rendering processing to write to the band buffer.
[0003]
Normally, a bitmap image written in a page buffer or band buffer is subjected to correction processing before being transmitted to a printing device or the like. For example, when the color space specified by the drawing command is RGB, the color space must be converted to CMYK in order to output to the printing apparatus. However, if color space conversion is uniformly performed on all bitmap images, a problem occurs in print quality, and therefore processing according to the drawing content (font, graphics, image, etc.) is desirable. In order to perform processing according to the drawing contents, attribute information indicating what kind of drawing contents (font, graphics, image, etc.) the contents of the respective drawing commands are required at the time of color conversion processing.
[0004]
Generally, the attribute information held by a drawing command is single for one drawing object, and attribute information is added for every one to several pixels when a bitmap image is generated by rendering processing. In an image processing apparatus that holds a band buffer and performs rendering processing in band units, the attribute information of the rendering command is passed to the intermediate code image data, and the attribute information is stored in the bitmap image developed in the band buffer. Added. Then, the developed bitmap image may be corrected with reference to the attribute information added to the bitmap image.
[0005]
Here, when the series of processing is performed only by the CPU, the processing load is large. For this reason, the CPU interprets the rendering command or the intermediate code image data and writes the bitmap image and attribute information to the memory. A method has been devised in which processing is performed by transferring a developed bitmap image and attribute information to an image processing circuit by DMA.
[0006]
For example, in the image forming apparatus described in Patent Document 1, when the CPU writes image data into the memory, attribute data indicating the attribute of the image data is included in the image data, and the DMA circuit reads the image data from the memory. Sometimes, in response to the attribute data included in the image data, an attribute parameter is set in the image processing circuit, and processing corresponding to the attribute is performed.
[0007]
In the printing apparatus described in Patent Document 2, image data created by interpreting a drawing command and attribute data of the image data are temporarily stored as pixel unit data, and the stored image data and attribute data are stored. Are simultaneously processed, and the image data is processed as image forming data according to the attribute data, thereby performing processing according to the attribute.
[0008]
As described above, since the drawing command or the intermediate code image data generally corresponds to one drawing object, the attribute information held by the drawing command or the intermediate code image data is single. However, in some cases, one drawing command or intermediate code image data may contain a plurality of drawing contents. In such a case, the attribute of the drawing contents can be accurately determined only by holding single attribute information. It is not possible to express it as a problem.
[0009]
As an example, there is a case where an area for holding a drawing command or intermediate code image data is insufficient. In this case, as an exceptional process, a rendering command or intermediate code image data for each band is temporarily rendered halfway, and a bitmap image is developed in a memory (or further compressed). Then, a single drawing command or intermediate code image data holding the address of the area where the developed bitmap image (or compressed bitmap image) is held is generated. As a result, the rendering command or intermediate code image data that has been rendered so far can be deleted, and the shortage of the area that holds the rendering command or intermediate code image data can be resolved.
[0010]
Conventionally, single information, for example, an image, is set as the attribute information of the drawing command or intermediate code image data generated at this time. However, there is a possibility that drawing contents having various attributes are included in the developed bitmap image. For this reason, an optimal process is not performed on a portion in which drawing content having an attribute different from the set single attribute information is rendered, which ultimately causes a problem in print quality.
[0011]
For example, also in the image processing apparatus described in Patent Document 3, when the storage capacity of the storage unit becomes a predetermined amount or less as described above, the object information is expanded into bitmap image data and compressed. Yes. At this time, in order to avoid the above-described problem, an area is detected for each attribute from the compressed bitmap image data, and object information for each attribute is generated. Thereby, the bitmap image data can be processed according to the attribute by the object information for each attribute. However, since an area having the same attribute is extracted and bitmap image data compressed for each object information of each attribute is associated, there is a problem that it takes a very long processing time.
[0012]
Japanese Patent Application Laid-Open No. H10-228561 also describes that one side of attribute information is given to bitmap image data. In this case, there is a problem with consistency with object information that is not expanded into a bitmap image. Although nothing is described in Patent Document 3 for this problem, for example, it is conceivable to uniformly hold one plane of attribute information for each object even for an unprocessed object. However, if all of the attribute information on one side is held, the amount of data increases, which is not a good idea.
[0013]
[Patent Document 1]
Japanese Patent No. 3254672
[Patent Document 2]
JP 2001-236191 A
[Patent Document 3]
JP 2001-332187 A
[0014]
[Problems to be solved by the invention]
The present invention has been made in view of the above-described circumstances. In any case, it is possible to perform optimum correction processing by holding attribute information in units of one or a plurality of pixels for a developed bitmap image. It is another object of the present invention to provide an image processing apparatus that develops attribute information in a memory at a high speed and reduces the amount of data to effectively use the memory.
[0015]
[Means for Solving the Problems]
The present invention relates to an image processing apparatus and an image processing method for creating a bitmap image based on an input drawing command, and performing a rendering process based on intermediate code image data generated from the drawing command or the drawing command by a drawing unit. A bitmap image and attribute information are generated, the bitmap image is stored in the image storage means together with the attribute information, and the bitmap image is subjected to correction processing according to the attribute information. Valid / invalid information indicating whether or not to use single attribute information set for each drawing target graphic is held in the image data, and the valid / invalid information is valid at the time of rendering processing by the drawing means. If the image storage means uses the single attribute information, the attribute information is stored in the image storage means. And the attribute information is set in the image storage means using the attribute information added for each pixel or a plurality of pixels of the drawing target graphic. Is.
[0016]
In this way, processing according to single attribute information as in the prior art is performed by holding valid / invalid information indicating whether single attribute information is used in the rendering command or intermediate code image data. For example, when attribute information is added to the image data for each pixel, processing according to the added attribute information is also possible. At this time, since single attribute information can also be used, it is not necessary to have attribute information for each pixel for all drawing commands or intermediate code image data, and the amount of data can be reduced.
[0017]
In particular, when the storage area of the instruction storage means is insufficient when the drawing instruction or intermediate code image data is held in the instruction storage means, the drawing instruction or intermediate data stored so far in the instruction storage means by the fallback process The code image data is rendered and the bitmap image and attribute information are expanded in the image storage means, and a single drawing command or intermediate code image data including the address of the area where the bitmap image and attribute information is held is generated. As a result, the storage area of the instruction storage means can be secured. For the single drawing command or intermediate code image data generated at this time, the valid / invalid information is set to invalid so that the single attribute information is not used. As a result, even when a graphic having a plurality of attributes is drawn during the rendering process, the attribute information of the graphic can be reflected as it is, and when the correction process is performed on the bitmap image, Optimal processing can be performed. Therefore, the image quality can be improved.
[0018]
The decompressed bitmap image and attribute information can be reduced or compressed into a compressed code, for example, in order to reduce the data amount. When compressing, different compression methods can be applied to each of the bitmap image and the attribute information. It is desirable to use a reversible method for compressing attribute information.
[0019]
Further, it is desirable that the drawing unit and the correction processing unit are configured with dedicated circuits. As an output destination of the image processing apparatus of the present invention, for example, a printing apparatus is assumed. However, the printing apparatus has various restrictions such as the need to supply a continuous bitmap image. It may be configured by a dedicated circuit so as to satisfy such restrictions. In addition, the time required for drawing and correction processing can be shortened.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a functional block diagram showing an embodiment of the present invention. In the figure, 1 is a host processing device, 2 is an image processing device, 3 is a printing device, 11 is an intermediate code generation unit, 12 is an intermediate code memory, 13 is an intermediate code image data development unit, 14 is a band buffer, and 15 is a correction. A processing unit 16 is an output control unit. The image processing apparatus 2 is an example of an image processing apparatus of the present invention or an apparatus that implements the image processing method of the present invention. In this example, after receiving a drawing command and generating intermediate code image data for each band, the band unit This shows the case of creating and outputting a bitmap image. Here, the drawing command is shown as being received from the host processor 1 such as a personal computer and outputting the created bitmap image to the printer 3. Note that the host processing device 1 and the image processing device 2 may be connected by a cable or may be communicably connected via a network such as a LAN. In many cases, the image processing apparatus 2 and the printing apparatus 3 are directly connected by wiring or the like. However, the present invention is not limited to this.
[0021]
The image processing apparatus 2 includes an intermediate code generation unit 11, an intermediate code memory 12, an intermediate code image data expansion unit 13, a band buffer 14, a correction processing unit 15, and an output control unit 16. The intermediate code generation unit 11 receives a drawing command sent from the host processing device 1, interprets the drawing command, and generates intermediate code image data for each band. The generated intermediate code image data can include single attribute information for a graphic drawn by the intermediate code image data. In addition, valid / invalid information indicating whether or not to use the single attribute information is included. Note that the intermediate code image data generated by the intermediate code generation unit 11 is normally set to use single attribute information as valid / invalid information. Of course, the present invention is not limited to this. For example, a case where attribute information for one or a plurality of pixels is added to a bitmap image together with a drawing command from the host processing apparatus 1 can be configured to be acceptable. Intermediate code image data set so as not to use one attribute information is generated. An example of the data format of the intermediate code image data will be described later.
[0022]
The intermediate code memory 12 is an instruction storage unit of the present invention, and stores the intermediate code image data generated by the intermediate code generation unit 11. Further, for example, the intermediate code generation unit 11 can also use the processing in the intermediate code generation unit 11 such as storing the drawing command received from the host processing device 1.
[0023]
The intermediate code image data development unit 13 includes the function of the drawing means of the present invention, reads intermediate code image data in band units from the intermediate code memory 12 and renders it, creates a bitmap image and attribute information, and creates a band buffer 14. Write to. Note that the attribute information can be added for each one or a plurality of pixels of the bitmap image.
[0024]
The intermediate code image data development unit 13 performs a fallback process when the intermediate code generation unit 11 holds the intermediate code image data in the intermediate code memory 12 and the storage area of the intermediate code memory 12 is insufficient. . In the fallback process, the intermediate code image data stored so far in the intermediate code memory 12 is rendered to develop a bitmap image and attribute information, and the address of the area in which the bitmap image and attribute information are held. Is a process of generating single intermediate code image data including Details of the fallback processing will be described later. By this fallback processing, a large number of intermediate code image data is replaced with one intermediate code image data, so that the storage area of the intermediate code memory 12 can be secured.
[0025]
The single intermediate code image data generated at this time is set not to use single attribute information as valid / invalid information. During the fallback process, there is a possibility that a figure having a plurality of attributes is drawn. Therefore, the developed bitmap image does not always have a single attribute. By setting the valid / invalid information so that the single attribute information is not used, the attribute information developed during the fallback process is displayed when rendering is performed based on the generated single intermediate code image data. It can be reflected as it is.
[0026]
Note that the bitmap image and the attribute information developed by the fallback process performed by the intermediate code image data development unit 13 can be reduced or compressed into a compressed code in order to reduce the data amount. When compressing, different compression methods can be applied to each of the bitmap image and the attribute information. It is desirable to use a reversible method for compressing attribute information.
[0027]
The band buffer 14 corresponds to the image storage means of the present invention, holds the band-unit bitmap image developed by the intermediate code image data development unit 13, and also provides attribute information for each one or several pixels of the bitmap image. Hold. For example, when storing a color bitmap image, the band buffer 14 stores it as plane sequential data stored as a separate plane for each color component, or holds data of all color components for each pixel. It can be stored as point sequential data. The band buffer 14 has a storage area for one band as well as a storage area for a plurality of bands. The intermediate code image data development unit 13 writes a bitmap image and attribute information, and the next correction processing unit. The processing by 15 or the reading by the output control unit 16 can be performed in parallel.
[0028]
The correction processing unit 15 performs correction processing on the bitmap image held in the band buffer 14 according to the attribute information similarly held in the band buffer 14. For example, color conversion processing according to each attribute can be performed. Of course, not only color conversion processing but also various correction processing according to attribute information can be performed. In addition, the correction processing unit 15 can also perform data conversion processing for output.
[0029]
The output control unit 16 reads the bitmap image developed in the band buffer 14 and transfers it to the printer 3 or the like.
[0030]
FIG. 2 is a more specific functional block diagram according to the embodiment of the present invention. In the figure, 21 is an input control unit, 22 is a drawing command interpretation unit, 23 is an intermediate code image data generation unit, 31 is an intermediate code image data interpretation unit, 32 is a compression / decompression processing unit, 33 is a reduction / enlargement processing unit, 41 is a color conversion unit, and 42 is a point plane conversion unit. Solid arrows indicate the flow of data, and broken arrows indicate the flow of control.
[0031]
In this example, the intermediate code generation unit 11 includes an input control unit 21, a drawing command interpretation unit 22, and an intermediate code image data generation unit 23. The intermediate code image data expansion unit 13 includes an intermediate code image data interpretation unit 31, a compression / decompression processing unit 32, and a reduction / enlargement processing unit 33. Further, the correction processing unit 15 includes a color conversion unit 41 and a point plane conversion unit 42.
[0032]
The input control unit 21 receives a drawing command sent from the host processor 1 or the like and stores it in the intermediate code memory 12. Then, the drawing command interpretation unit 22 is activated. The drawing command interpretation unit 22 sequentially reads and interprets the drawing commands stored in the intermediate code memory 12. Then, information (attribute information, color information, edge information, image, etc.) obtained by the interpretation processing of the drawing command is delivered to the intermediate code image data generation unit 23. The intermediate code image data generation unit 23 executes various functions related to the generation of intermediate code image data in the intermediate code generation unit 11 described above, and the intermediate code image data in band units from the information passed from the drawing command interpretation unit 22. Is stored in the intermediate code memory 12.
[0033]
FIG. 3 is an explanatory diagram of an example of intermediate code image data of an image. Here, an example of the format of the intermediate code image data for the drawing object is shown. Examples of drawing objects include graphics, fonts, and images. Of these, graphics and fonts can be expressed only with intermediate code image data, but in the case of images (including reduced / compressed images), intermediate code image data and images (including reduced / compressed images). It consists of two. FIG. 3A shows the format of intermediate code image data in the case of drawing objects other than images, such as graphics and fonts, and FIG. 3B shows the format of intermediate code image data in the case of images. Yes.
[0034]
In any drawing object, the intermediate code image data includes a header part and a body part. The header portion includes a command ID, an attribute information field, and other information. When the drawing object is an image, an address at which an image (including a reduced / compressed image) exists is further displayed as “image pointer”. ”And associate with the image. In the body portion, information for specifying a drawing area created from the edge information passed from the drawing command interpretation unit 22, for example, run length information is held.
[0035]
Here, in the attribute information field, conventionally, attribute information indicating the drawing object passed from the drawing command interpreter 22 is set. In this example, valid / invalid information is set in the attribute information field together with this attribute information. The attribute information set in the attribute information field is information indicating a single attribute in the intermediate code image data. That is, if the drawing object is an image, this indicates that the common attribute “image” is applied to the entire image. In the case of graphics and fonts, it is guaranteed that the drawing object is the same in all the drawing areas. However, in the case of an image (including a reduced / compressed image), there is no guarantee that it is only an image. For some reason, a plurality of drawing objects such as fonts and graphics may be handled as an image in a developed state. For example, there is a case where the above-described fallback processing is performed, and a case where an image with an attribute specified from the host processing device 1 is received is also conceivable. However, since the conventional intermediate code image data format can only have a single drawing object information set in the attribute information field, it cannot cope with the above case, and the printing quality cannot be guaranteed. The problem occurs.
[0036]
The intermediate code image data format of the present invention has valid / invalid information in order to solve the above problems. This valid / invalid information indicates whether or not to use single attribute information set in the attribute information field in the intermediate code image data described above. When this valid / invalid information indicates that it is valid, single attribute information in the attribute information field is used. If the valid / invalid information indicates invalidity, the single attribute information in the attribute information field is not used, for example, attribute information added to the image is used.
[0037]
In the example shown in FIG. 3, valid / invalid information is also stored in the attribute information field. As a specific example, when the size of the attribute information field is 8 bits, the attribute information is expressed by lower 4 bits (for example, graphics = 1, font = 2, image = 3, etc.), and valid / invalid information by the upper 4 bits. (For example, valid = 0, invalid = 0xf0). The logical sum of this attribute information and valid / invalid information is stored in the attribute information field. Of course, it is needless to say that the present invention is not limited to this specific example, and it is sufficient that valid / invalid information of 1 bit or more is included in the intermediate code image data.
[0038]
In the case of the intermediate code image data of the image shown in FIG. 3B, the location where the image exists is indicated by the pointer to the image as described above. The image at this time is only an image as shown in FIG. 3C when the valid / invalid information is set to valid. However, when the valid / invalid information is set to invalid, as shown in FIG. 3D, the image includes attribute information associated with one or more pixels of the image.
[0039]
In this way, when a drawing object having a plurality of attributes such as fonts and graphics is treated as an image for some reason, it is set as invalid as valid / invalid information in the attribute information field, and Attribute information for each one or a plurality of pixels is added to an image (including a reduced / compressed image) indicated by a pointer to the image stored in the header portion of the intermediate code image data. As a result, the attribute information for each pixel can be reliably held, and the correction processing unit 15 can perform the correction process according to the attribute information to guarantee the print quality.
[0040]
Returning to FIG. 2, the intermediate code image data interpretation unit 31 of the intermediate code image data development unit 13 sequentially extracts and interprets the intermediate codes from the intermediate code memory 12, renders them in the band buffer 14 in band units, and creates a bitmap image. Expand to. The attribute information corresponding to the drawn pixel is also stored in the band buffer 14 together with the bitmap image. At this time, depending on the intermediate code image data, processing can be performed using the compression / decompression processing unit 32, the reduction / enlargement processing unit 33, and the like. Further, the intermediate code image data development unit 13 performs the above-described fallback processing when the free space of the intermediate code memory 12 becomes small. Even in the fallback processing, drawing processing is performed on the band buffer 14 and attribute information is also stored. At this time, generally, graphics having various attributes are drawn. Therefore, invalidity is set as valid / invalid information in the intermediate code image data generated in the fallback process. Also, attribute information is added to the image of the intermediate code image data.
[0041]
Note that the bitmap image and attribute information drawn by the fallback process are stored in the intermediate code memory 12, but if the bitmap image remains as it is, the area of the intermediate code memory 12 may be compressed. In order to cope with such a case, in order to reduce the amount of data, for example, the data can be reduced by the reduction / enlargement processing unit 33 or compressed by the compression / decompression processing unit 32. In the case of compression, it is possible to use different compression methods for the bitmap image and the attribute information. For at least attribute information, it is desirable to use a reversible compression method.
[0042]
The compression / decompression processing unit 32 decompresses the compressed image and writes it in the band buffer 14. For example, when the drawn bitmap image is compressed and stored as a compressed code by performing fallback processing, the compressed / decompressed processing unit 32 compresses the compressed bitmap image and stores the compressed code in the intermediate code memory 12. Also in this case, when the data is written into the band buffer 14, the compression / decompression processing unit 32 performs decompression processing.
[0043]
When the object to be drawn is an image, the reduction / enlargement processing unit 33 reduces or enlarges the image according to the enlargement ratio in the intermediate code image data stored in the intermediate code memory 12. For example, when the bitmap image drawn by the fallback process is reduced and saved, the drawn bitmap image is reduced and stored in the intermediate code memory 12. Also in this case, when writing into the band buffer 14, the reduction / enlargement processing unit 33 performs enlargement processing as necessary.
[0044]
The color conversion unit 41 of the correction processing unit 15 performs color space conversion processing, color correction processing, and the like on the bitmap image in the band buffer 14. At this time, in accordance with the attribute information stored in the band buffer 14 together with the bitmap image, it is possible to perform an optimum process for the drawing figure of each attribute.
[0045]
When storing the bitmap image in the band buffer 14, the point plane conversion unit 42 stores it as plane sequential data stored as a separate plane for each color component, and the printing device 3 stores data for all color components for each pixel. When requesting the dot sequential data that holds the data, the plane sequential data is converted to the dot sequential data. Alternatively, when the bitmap image is stored in the band buffer 14, it is stored as dot sequential data, and when the printing apparatus 3 requests frame sequential data, the dot sequential data is converted to frame sequential data.
[0046]
Note that all or part of the intermediate code image data development unit 13 and the correction processing unit 15, or the band buffer 14 and the like can be configured by a dedicated circuit. This makes it possible to perform processing at high speed.
[0047]
FIG. 4 is a flowchart showing an example of the overall processing in the embodiment of the present invention. For example, in a print system in which a host processing device 1 such as a personal computer and an image processing device 2 are connected via a network or the like, a rendering command is sent from the host processing device 1 to the image processing device 2 through the network or the like. Therefore, the image processing apparatus 2 receives the drawing command by the input control unit 21 and stores it in the intermediate code memory 12.
[0048]
When a series of drawing commands is received or in parallel with the reception of the drawing commands, the drawing command interpretation unit 22 and the intermediate code image data generation unit 23 operate. In S51, the drawing command interpretation unit 22 determines whether or not there is a drawing command received from the host processor 1, and if it exists, interprets the drawing command in S52. Then, the interpretation result is passed to the intermediate code image data generation unit 23.
[0049]
The image data generation unit 23 generates intermediate code image data for each band based on the interpretation result passed from the drawing command interpretation unit 22. When the minimum value of the coordinates in the Y direction of the drawing area based on the drawing command is Ymin and the maximum value is Ymax, the processing of S54 to S61 is performed for each band including Ymax from the band including Ymin. repeat.
[0050]
In S54, intermediate code image data is generated for a portion to be drawn in the band being processed among the objects drawn by the drawing command. In S55, it is determined whether or not to enable the attribute information field. For this determination, for example, when the drawing object is an image, it is only necessary to determine whether or not attribute information is added to one or more pixels together with the image. Separately, if no attribute information is added, the single attribute information may be applied, and in S56, it is set in the attribute information field that the single attribute information is valid as valid / invalid information. If attribute information is added, the added attribute information is used, and in S57, setting is made to invalidate a single attribute information as valid / invalid information.
[0051]
The intermediate code image data generated by the intermediate code image data generation unit 23 is stored in the intermediate code memory 12. At this time, there is a free area that can store the intermediate code image data in the intermediate code memory 12 in S58. It is determined whether or not. If there is a free area, the intermediate code image data generated by the intermediate code image data generation unit 23 is stored in the intermediate code memory 12 in S60.
[0052]
If there is not enough free space to store the intermediate code image data generated by the intermediate code image data generation unit 23 in the intermediate code memory 12, a fallback process is performed in S59. An example of the process for the fallback process will be described later. After the space area of the intermediate code memory 12 is increased by this fallback processing, the intermediate code image data generated by the intermediate code image data generation unit 23 is stored in the intermediate code memory 12 in S60.
[0053]
In this way, when intermediate code image data for one band is generated for a certain drawing command and stored in the intermediate code memory 12, from S61 to S53, intermediate code image data for another band is generated for the same drawing command. Return and repeat the process. When intermediate code image data is generated for all the bands drawn by the drawing command for a certain drawing command, the process returns to S51. Then, processing for the next drawing command is performed. When intermediate code image data for each band is generated for all drawing commands, the process proceeds to S62.
[0054]
In S62 to S64, the intermediate code image data interpretation unit 31 sequentially performs rendering processing in S63 for all bands. That is, the intermediate code image data interpretation unit 31 reads the intermediate code image data corresponding to the band being processed from the intermediate code memory 12, performs rendering processing, and writes the bitmap image and attribute information to the band buffer 14. When the rendering processing is completed for the intermediate code image data for one band, when performing real-time output, the correction processing unit 15 immediately performs the bitmap image correction processing using the attribute information, and the output control unit 16 It is output to the printing device 3 or the like. When real-time output is not performed, the bitmap image and attribute information in the band buffer 14 are compressed by the compression / decompression processing unit 32 and stored in the intermediate code memory 12. A more detailed description of the rendering process will be described later.
[0055]
After performing the rendering process in S63 for all the bands in this way, it is determined whether or not real-time output has been performed in S65. If real-time output is being performed, output has already been completed, so this processing ends.
[0056]
If real-time output is not performed, in S66 to S68, decompression and output processing in S67 are sequentially performed for all bands. That is, when real-time output is not performed, the bitmap image and attribute information generated for each band as described above are compressed and stored in the intermediate code memory 12 as a compressed code. Accordingly, the compressed code is read out in order, decompressed by the compression / decompression processing unit 32, developed in the band buffer 14, and output from the output control unit 16 to, for example, the printer 3.
[0057]
Note that the series of operations described above outputs, for example, a bitmap image for one page. For example, when outputting a bitmap image of a plurality of pages, the processing shown in FIG. 4 is performed for each page. Just do it every time.
[0058]
FIG. 5 is a flowchart showing an example of fallback processing according to the embodiment of the present invention. The outline of the fallback process is that all intermediate code image data of a certain band is temporarily expanded in a band buffer, and a single intermediate code image data for a bitmap image expanded in the band buffer is generated to generate intermediate code image data. The shortage of the holding area is solved. Here, description will be made assuming that fallback processing is performed on intermediate code image data for one band. Of course, it is also possible to perform fallback processing for a plurality of bands by repeating the following processing.
[0059]
The process between S71 and S81 is executed for each of the intermediate code image data corresponding to the band on which the fallback process is performed. In S72, it is determined whether or not the intermediate code image data is intermediate code image data (image system) for drawing an image. This determination can be made based on the command ID or attribute information. In the case of intermediate code image data other than image data, in S79, the attribute information in the attribute information field in the intermediate code image data is used as attribute information, and the drawing process to the band buffer 14 is performed in S80. For the pixels written by this drawing process, the attribute information in the attribute information field in the intermediate code image data is written in the band buffer 14.
[0060]
Also, for image-based intermediate code image data, if the image to be rendered in S73 is compressed data, the compression / decompression processing unit 32 performs decompression processing in S74, and the image to be rendered (decompressed). If the image is a reduced image, the reduction / enlargement processing unit 33 performs enlargement processing in S76. If the image to be drawn does not match the resolution when the image is developed in the band buffer 14, enlargement or reduction processing for matching the resolution is performed in S76. Whether or not the data is compressed data and whether or not the data is compressed data can be determined by a command ID or the like in the intermediate code image data.
[0061]
Here, it is determined whether the validity / invalidity information of the intermediate code image data being processed is valid, that is, whether or not the setting is to use the attribute information in the attribute information field in the intermediate code image data. If the valid / invalid information is valid, the attribute information in the attribute information field in the intermediate code image data is used as the attribute information in S79. If invalid, the attribute information added to the image is used in S78. And In S80, the drawing process to the band buffer 14 is performed. At this time, if the valid / invalid information is valid as the attribute information corresponding to the pixel written by the drawing process, the attribute information in the attribute information field in the intermediate code image data is written in the band buffer 14 and the valid / invalid information is stored. If invalid, the attribute information added to the image is written to the band buffer 14.
[0062]
By performing such processing for each of the intermediate code image data for one band, the band buffer 14 is rendered with the intermediate code image data corresponding to the band generated up to the start of the fallback processing. Bitmap images and attribute information are stored. The drawn intermediate code image data is deleted from the intermediate code memory 12, and the free area of the intermediate code memory 12 can be increased.
[0063]
Here, the valid / invalid information is not determined for intermediate code image data other than the image system, but of course, the valid / invalid information may also be determined for intermediate code image data other than the image system.
[0064]
When the drawing to the band buffer 14 is completed, the bitmap image in the band buffer 14 is transferred to the intermediate code memory 12 and stored in the intermediate code memory 12 as an image of new intermediate code image data generated in S90 described later. Although the intermediate code image data is deleted by the above-described process and the free area of the intermediate code memory 12 is increased, the area for storing the image may be insufficient. In order to cope with such a case, the image storage area in the intermediate code memory 12 is insufficient by performing reduction processing or compression processing (reversible or lossy) on the bitmap image developed in the band buffer. Can be eliminated. Whether to perform the reduction process or the compression process may be set in advance, or may be determined from intermediate code image data or a drawn bitmap image.
[0065]
When performing these processes, in this example, the bitmap image is processed for each color component, and the loop of S82 to S89 is executed four times for the color components R, G, B and attribute information. For example, it is assumed that the drawing is performed in the band buffer 14 as frame sequential data during the drawing process in S80. Of course, in the case of dot-sequential data, there are two loops of bitmap image and attribute information.
[0066]
In S83, it is determined whether or not the image is to be reduced. If the image is to be reduced, the reduction / enlargement processing unit 33 performs reduction (or enlargement) processing in S84. In S85, it is determined whether or not compression is performed, and in the case of compression, it is determined in S86 whether or not a reversible compression method is used as the compression method. If not compressed, the process for the color component or attribute information is finished, and the process moves to the process for the next color component or attribute information. If compression processing is performed and the lossless compression method is selected, the compression / decompression processing unit 32 performs compression by the lossless compression method in S87. When compression processing is performed and the lossy compression method is selected, the compression / decompression processing unit 32 performs compression by the lossy compression method in S88. In order to reduce the amount of data, it is better to use a lossy compression method, but the original data cannot be accurately restored. Therefore, it is desirable to always use a lossless compression method for attribute information. When neither reduction processing nor compression processing is performed, the bitmap image and attribute information expanded in the band buffer 14 are stored in the intermediate code memory 12 as they are.
[0067]
After each color component and attribute information of the bitmap image is reduced or compressed as necessary, one intermediate code image data is generated for the bitmap image developed in the band buffer 14 in S90. To do. In S91, invalid is set as valid / invalid information in the intermediate code image data. A command ID corresponding to whether or not reduction processing or compression processing has been performed is set as the command ID of the intermediate code image data.
[0068]
The intermediate code image data and the bitmap image generated in this way are stored in the intermediate code memory 12, and are thereafter handled in the same manner as the intermediate code image data generated from the rendering command by the intermediate code image data generation unit 23.
[0069]
FIG. 6 is a schematic diagram of an example of a data format when attribute information is added to a bitmap image. FIG. 6A shows an RGB frame sequential bitmap image, which is composed of an image plane composed of color components R, an image plane composed of color components G, and an image plane composed of color components B. At the same time, an attribute information plane is provided, and the attribute information of the pixel is arranged at the same position as each pixel position in the R, G, and B image planes.
[0070]
FIG. 6B shows a case where a reduction process is performed in the fallback process shown in FIG. 5 with respect to the bitmap image and attribute information of such a data format. Here, a case where the data is reduced to ½ by thinning processing is shown, and even pixel data is thinned out from each image plane and attribute information plane. Of course, the reduction processing method and reduction ratio are arbitrary.
[0071]
Further, when compressing the bitmap image and attribute information of the data format shown in FIG. 6A or 6B, the image plane and attribute information plane are also compressed. As a result, as shown in FIG. 6C, an R component compressed code, a G component compressed code, a B component compressed code, and an attribute information compressed code are generated.
[0072]
FIG. 7 is a schematic diagram of another example of a data format when attribute information is added to a bitmap image. FIG. 6 shows the case of frame sequential, but FIG. 7 shows the case of a dot sequential bitmap image. In the case of dot sequential, all the color component data (R component data, G component data, B component data) is included as data for each pixel. Therefore, as shown in FIG. 7A, the attribute information may be added for each pixel. As a result, four pieces of R component data, G component data, B component data, and attribute information are held for each pixel.
[0073]
FIG. 7B shows a case where a reduction process is performed on the bitmap image and attribute information of such a data format in the fallback process shown in FIG. 5 described above. Here, a case where the data is reduced to ½ by thinning processing is shown, and even pixel data is thinned out from each image plane and attribute information plane. Of course, the reduction processing method and reduction ratio are arbitrary.
[0074]
Further, when compressing the bitmap image and attribute information of the data format shown in FIG. 7A or FIG. 7B, the attribute information is separated, and the RGB bitmap image and the attribute information are separated separately. Compress it. Various methods are known as compression methods for RGB bitmap images, and the format differs depending on each compression method. In addition, when the attribute information is separated, a compression method different from the RGB bitmap image can be applied. For example, when an irreversible compression method is applied to an RGB bitmap image, a lossless compression method can be applied to attribute information. By such processing, as shown in FIG. 7C, a compression code for the RGB bitmap image and a compression code for the attribute information are respectively generated.
[0075]
As described with reference to FIG. 4, all rendering commands transmitted from the host processing device 1 are converted into intermediate code image data, and then rendering processing is performed in band units. When the fallback process is performed at the time of generating the intermediate code image data, the intermediate code image data generated by the fallback process is also subject to the rendering process.
[0076]
FIG. 8 is a flowchart illustrating an example of rendering processing. Here, rendering processing for one band is shown, and this rendering processing is repeatedly executed for each band in S62 and S64 of FIG.
[0077]
First, in S101, the presence / absence of intermediate code image data is determined. If there is intermediate code image data to be rendered, the intermediate code image data is rendered in the band buffer 14 by performing the processing of S102 to S110. Note that the processing of S102 to S110 is the same as the processing of S72 to S80 of the fallback processing shown in FIG. During this process, as with the fallback process described above, either the attribute information in the intermediate code image data or the attribute information added to the image is selected according to the valid / invalid information, and the rendered bitmap image is supported. In addition, the attribute information is written in the band buffer 14. The same applies to the fallback processing described above, but the intermediate code image data may include intermediate code image data generated by the fallback processing performed prior to the drawing processing. is there. In such intermediate code image data, the valid / invalid information is set to invalid, and the attribute information is written in the band buffer 14 using the attribute information added to the image. If the drawing process of S110 is performed, the process returns to S101 and proceeds to the process of the next intermediate code image data.
[0078]
When all the intermediate code image data for one band is drawn, the process proceeds from S101 to S111. In S111, it is determined whether the color space of the drawn bitmap image matches the color space of the output bitmap image. If they match, the color space conversion process is unnecessary, and the process proceeds to the next S113. If the color spaces do not match, in S112, the color conversion unit 41 performs a color space conversion process to the color space of the output bitmap image. For example, when the color space of the drawn bitmap image is the RGB color space and the color space of the output bitmap image is the CMYK color space, conversion processing from the RGB color space to the CMYK color space is performed. At this time, according to the attribute information added to the bitmap image, it is possible to perform the optimum color space conversion processing for each attribute figure. For example, it is possible to perform color space conversion processing for the purpose of faithful color reproduction for the image portion, and color space conversion processing with an emphasis on distinguishability for the character portion or the like. Of course, what kind of color space conversion processing is performed according to the attribute information is arbitrary.
[0079]
In addition, although color space conversion processing is shown here as an example, of course, in addition to this, image processing such as color adjustment, gamma adjustment of each color component, and other various filtering processing, as well as attribute information as necessary Can be used.
[0080]
In S113, it is determined whether or not the data format (dot sequential or frame sequential) of the bitmap image stored in the band buffer 14 matches the data format of the output bitmap image. As an example, here, it is assumed that the data format of the output bitmap image is a frame sequential data format, and if the bitmap image stored in the band buffer 14 is a dot sequential data format, in S114 The plane conversion unit 42 converts the data into a plane sequential data format. Of course, if the data format required for the output bitmap image is a dot sequential data format, the frame sequential bitmap image is converted to the dot sequential data format.
[0081]
In this manner, after various processing is performed on the bitmap image stored in the band buffer 14, it is determined whether or not to perform real-time output in S115. When performing real-time output, in S117, the output control unit 16 reads out a bitmap image from the band buffer 14 and outputs the bitmap image to an external device such as the printing device 3 or the like. The printing device 3 receives the bitmap image from the image processing device 2 and performs printing processing.
[0082]
If real-time output is not performed, the bitmap image stored in the band buffer 14 is compressed by the compression / decompression processing unit 23 and the compressed data is stored in the intermediate code memory 12 in S116. Alternatively, when storing compressed data for a plurality of pages, it is possible to provide a new external storage device in the image processing device 2. In the case of outputting, the compression / decompression processing unit 32 performs decompression processing in S67 of FIG. 4 and writes it in the band buffer 14, and the output control unit 16 outputs the bitmap image written in the band buffer 14 to the printing device 3. Is output for
[0083]
Whether or not to perform real-time output can be determined by whether or not the processing time required for the above-described rendering processing in units of bands, color conversion processing, and point plane conversion processing is in time for the output time of the printing apparatus 3. When the output time of the printing apparatus 3 is in time, real-time output is possible. By performing real-time output, the time until the printing apparatus 3 starts printing can be shortened. Even when the output time of the printing apparatus 3 is not in time or when the output time of the printing apparatus 3 is in time, the rendered bitmap image may be compressed and stored according to the settings and output while being decompressed. Since the decompression process and the output process can be performed in a shorter time compared to the rendering process or the like, it can be handled even if the printing apparatus 3 is somewhat fast.
[0084]
In the above description, the case where the band buffer 14 is provided and the rendering process and the output process are performed in band units has been described. The present invention is not limited to the case where processing is performed in units of bands as described above, but is also effective in the case where a page memory is provided and processing is performed in units of pages. In other words, when attribute information is sent together with an image, the setting to use the sent attribute information with priority is performed in the drawing command. In addition, when a large amount of drawing commands are sent, if the free space of the memory is insufficient, a fallback process is performed using the page memory, and attribute information is added to each pixel or pixels at that time. The attribute information added to the image when rendering processing is performed later can be reflected, and the optimum processing can be performed in the subsequent correction processing to guarantee the image quality.
[0085]
【The invention's effect】
As is clear from the above description, according to the present invention, it is possible to set valid / invalid information indicating whether or not to use single attribute information held by a rendering command or intermediate code image data. It is possible to handle an image or the like to which attribute information is added for each one or a plurality of pixels, and it is possible to hold attribute information for all pixels even when a fallback process occurs. As a result, the correction processing according to the attribute information can be performed accurately, and the image quality can be guaranteed. For example, when printing is performed by a printing device based on the output bitmap image, the print quality can be guaranteed. Also, if attribute information is always held for one or more pixels, the amount of data increases and a large amount of memory is required. However, it is possible to switch between drawing commands or single attribute information in intermediate code image data. Thus, the amount of data for attribute information is not increased unnecessarily, and the memory can be used effectively. Furthermore, since the processing for valid / invalid information is not so complicated, the drawing means and the correction processing means can be configured by a dedicated circuit, and high-speed processing is possible.
[Brief description of the drawings]
FIG. 1 is a functional block diagram showing an embodiment of the present invention.
FIG. 2 is a more specific functional block diagram according to the embodiment of the present invention.
FIG. 3 is an explanatory diagram of an example of intermediate code image data of an image.
FIG. 4 is a flowchart illustrating an example of overall processing according to an embodiment of the present invention.
FIG. 5 is a flowchart showing an example of fallback processing according to the embodiment of the present invention.
FIG. 6 is a schematic diagram illustrating an example of a data format when attribute information is added to a bitmap image.
FIG. 7 is a schematic diagram of another example of a data format when attribute information is added to a bitmap image.
FIG. 8 is a flowchart illustrating an example of rendering processing.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... High-order processing apparatus, 2 ... Image processing apparatus, 3 ... Printing apparatus, 11 ... Intermediate code production | generation part, 12 ... Intermediate code memory, 13 ... Intermediate code image data expansion | deployment part, 14 ... Band buffer, 15 ... Correction processing part, DESCRIPTION OF SYMBOLS 16 ... Output control part, 21 ... Input control part, 22 ... Drawing command interpretation part, 23 ... Intermediate code image data generation part, 31 ... Intermediate code image data interpretation part, 32 ... Compression / decompression processing part, 33 ... Reduction / enlargement Processing unit, 41... Color conversion unit, 42.

Claims (13)

  In an image processing apparatus for creating a bitmap image based on an input drawing command, rendering processing is performed based on the drawing command or intermediate code image data generated from the drawing command to generate the bitmap image and attribute information Drawing means, image storage means for holding bitmap image and attribute information generated by the drawing means, and bitmap image held in the image storage means are held in the image storage means Correction processing means for performing correction processing according to the attribute information, and the drawing command or the intermediate code image data indicates whether or not to use a single attribute information set for each figure to be drawn The valid / invalid information is held, and the drawing means has the valid / invalid information valid. In the rendering process, the single attribute information is used to set the attribute information in the image storage means, and in the case of invalidity, one or a plurality of graphics to be rendered are displayed. An image processing apparatus, wherein attribute information is set in the image storage means using attribute information added for each pixel.   Command storage means for holding the rendering command or the intermediate code image data, and the rendering means renders the rendering command or the intermediate code image data, and stores the bitmap image and attribute information in the image storage means. An image data expansion unit that expands and executes a fallback process when a storage area of the command storage unit is insufficient, and the image data expansion unit includes a single drawing instruction or intermediate code image generated by the fallback process The image processing apparatus according to claim 1, wherein the valid / invalid information of data is set to invalid so that the single attribute information is not used.   Command storage means for holding the drawing command or the intermediate code image data, the drawing means rendering processing the drawing command or the intermediate code image data, and a reduction / enlargement processing means for reducing or enlarging an image. Image data expansion means for expanding a bitmap image and attribute information in the image storage means and performing fallback processing when a storage area of the instruction storage means is insufficient, and the reduction / enlargement processing means includes: The bitmap image and attribute information are reduced during the fallback processing by the image data expansion means, and the image data expansion means is configured to enable / disable the single drawing command or intermediate code image data generated by the fallback processing. Set the information to invalid and do not use the single attribute information The image processing apparatus according to claim 1, wherein the Unisuru.   Command storage means for holding the drawing command or the intermediate code image data, wherein the drawing means performs compression / expansion processing means for compressing / decompressing an image, and rendering processing for the drawing command or the intermediate code image data The image storage means expands the bitmap image and the attribute information, and has an image data expansion means for performing a fallback process when the storage area of the instruction storage means is insufficient, the compression / decompression processing means, In the fallback processing by the image data expansion means, the bitmap image and attribute information are compressed into a compressed code, and the image data expansion means is a single drawing command or intermediate code image data generated by the fallback processing. Set the valid / invalid information to invalid and the single attribute information The image processing apparatus according to claim 1, characterized in that to avoid using.   Command storage means for holding the drawing command or the intermediate code image data, wherein the drawing means performs compression / expansion processing means for compressing / decompressing an image, and rendering processing for the drawing command or the intermediate code image data The image storage means expands the bitmap image and the attribute information, and has an image data expansion means for performing a fallback process when the storage area of the instruction storage means is insufficient, the compression / decompression processing means, In the fallback processing by the image data expansion means, the bitmap image and the attribute information are compressed by different compression methods into compressed codes, and the image data expansion means has a single drawing command generated by the fallback processing. Or invalidate the valid / invalid information of intermediate code image data Constant, the image processing apparatus according to claim 1, characterized in that to avoid using the single attribute information.   6. The image processing apparatus according to claim 4, wherein a compression method for the expanded attribute information is a reversible method.   The image processing apparatus according to claim 1, wherein the drawing unit and the correction processing unit are configured by dedicated circuits.   In the image processing method for creating a bitmap image based on an input drawing command, the drawing means performs a rendering process based on the drawing command or intermediate code image data generated from the drawing command, and the bitmap image and attribute Information is generated and the bitmap image is held together with attribute information in an image storage means, and the correction processing means performs correction processing according to the attribute information for the bitmap image, the drawing command or The intermediate code image data holds valid / invalid information indicating whether or not to use a single attribute information set for each drawing target graphic. During the rendering process, the valid / invalid information is stored in the intermediate code image data. The image storage means using the single attribute information when indicating that it is valid If the attribute information is set to indicate that it is invalid, the attribute information is set in the image storage means using the attribute information added for each pixel or a plurality of pixels of the drawing target graphic. A featured image processing method.   When the drawing instruction or the intermediate code image data is held in the instruction storage means, and the storage area of the instruction storage means is insufficient, the drawing instruction or the intermediate code stored in the instruction storage means until then The image data expansion means of the drawing means renders the image data, expands the bitmap image and attribute information in the image storage means, and includes a single address including the address of the area where the bitmap image and attribute information are held. A storage area of the command storage unit is secured by generating a drawing command or intermediate code image data, and the valid / invalid information of the generated single drawing command or intermediate code image data is set to invalid and the single The attribute information is not used and the expanded attribute information is applied. The image processing method according to claim 8.   When the drawing instruction or the intermediate code image data is held in the instruction storage means, and the storage area of the instruction storage means is insufficient, the drawing instruction or the intermediate code stored in the instruction storage means until then The image data expansion means of the drawing means renders the image data, expands the bitmap image and attribute information in the image storage means, and the reduction / enlargement processing means of the drawing means converts the bitmap image and attribute information to the image storage means. The storage area of the instruction storage means is secured and generated by generating a single drawing instruction or intermediate code image data that includes the reduced bitmap image and the address of the area in which the attribute information is held. Invalidate the valid / invalid information of single drawing command or intermediate code image data The image processing method according to claim 8 in which the constant and not to use the single attribute information, characterized by applying the attribute information described above expanded.   When the drawing instruction or the intermediate code image data is held in the instruction storage means, and the storage area of the instruction storage means is insufficient, the drawing instruction or the intermediate code stored in the instruction storage means until then The image data expansion means of the drawing means renders the image data, expands the bitmap image and attribute information in the image storage means, and the compression / decompression processing means of the drawing means converts the bitmap image and attribute information to the image storage means. Compressed into compressed code, and secures the storage area of the instruction storage means by generating a single drawing instruction or intermediate code image data including the address of the area where the bitmap image and attribute information compressed code are held The generated single drawing command or intermediate code image data is valid. The image processing method according to claim 8 in which invalid information is set to disable and not use the single attribute information, characterized by applying the attribute information described above expanded.   When the drawing instruction or the intermediate code image data is held in the instruction storage means, and the storage area of the instruction storage means is insufficient, the drawing instruction or the intermediate code stored in the instruction storage means until then The image data expansion means of the drawing means renders the image data, expands the bitmap image and attribute information in the image storage means, and compresses the bitmap image and attribute information by different compression methods. The decompression processing means compresses the compressed code into a compressed code, and generates the single drawing instruction or intermediate code image data including the address of the area where the bitmap image and the attribute information compressed code are held, thereby storing the instruction storage means A single drawing command or medium generated The image processing method according to claim 8 and disabled the valid / invalid information of the code image data so as not to use the single attribute information, characterized by applying the attribute information described above expanded.   13. The image processing method according to claim 11, wherein a compression method for the expanded attribute information is a reversible method.

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