JP5407912B2 - Image processing apparatus, image processing method, image processing program, and recording medium - Google Patents

Description

  The present invention relates to an image processing apparatus, an image processing method, an image processing program, and a recording medium. Specifically, input image data is temporarily compressed in variable length and stored in a memory, and then the compressed data in the memory is decompressed and output. The present invention relates to an image processing apparatus, an image processing method, an image processing program, and a recording medium.

  In an image processing apparatus such as a copying apparatus, a printer apparatus, a facsimile apparatus, or a composite apparatus, when image data of a document read by a scanner is formed and output by a printer, the following processing procedure is performed. In other words, the image processing apparatus compresses the image data read and output by the scanner into a variable length compressed by a compressor to be compressed data, and stores the data by a DMAC (Direct Memory Access Controller) without using a CPU (Central Processing Unit). And save it as compressed data for output. After that, the image processing apparatus reads the compressed data in the memory with the DMAC, decompresses it with the decompressor, performs necessary image processing, and prints it out with the printer.

  In such a series of image data processing, since the operation of the scanner is performed at a constant speed, it is necessary to transfer data to the memory at a constant speed.

  In order to improve the processing speed, the image data read by the scanner is compressed and stored in the memory, and before all the compressed data is stored in the memory, reading of the compressed data in the memory is started. Then, a sequential process is performed in which the read compressed data is decompressed and printed by the plotter. In this case, the entire transfer process can be performed quickly by appropriately linking the compression transfer process for compressing the image data and transferring and storing it in the memory and the decompression transfer process for expanding the compressed data in the memory and transferring it to the plotter. This is important for shortening the copy speed, particularly the processing time of the first copy, which is the first copy.

  Also, today, image data can be transferred and reused in addition to CMYK image data of C (cyan), M (magenta), Y (yellow), and K (black) for print output. It is necessary to handle RGB image data of (red), G (green), and B (blue) on the memory. Therefore, in today's image processing apparatuses, the transfer path of image data has become complicated, which is one of the causes of a long first copy time from reading a document to printing output when performing a copy operation. .

  In addition, when the input image data is variable-length compressed by the compressor and saved as compressed data in the memory, the data size of the compressed data compressed by the compressor is not constant. In the sequential processing performed in this manner, the processing time in the compressor varies depending on the compression rate of the image data, and the first copy time cannot be guaranteed. That is, in the transfer of compressed data by DMAC, when a predetermined amount of compressed data is accumulated in the buffer, it is DMA-transferred and written to the memory, and a predetermined amount of compressed data written in the memory is read and written to the buffer. The compressed data in the buffer is output to the decompressor. Therefore, if there is a variation in the processing time in the compressor due to the compression rate of the compressor, there will be a variation in the time for which the predetermined amount of compressed data is stored in the buffer, and the compression transfer and decompression transfer will be linked appropriately. Can not be.

  Conventionally, after the image data is compressed in variable length and accumulated in the write side buffer, it is transferred to the memory and stored, and when the stored compressed data is read and decompressed, the accumulation amount in the write side buffer is the first. A technique has been proposed in which the transfer is performed at the earlier timing when the predetermined amount is reached or when a predetermined time has elapsed from the start of writing before reaching the first predetermined amount (see Patent Document 1).

  However, in the above prior art, even if the compressed data compressed by the variable length by the compressor is not stored in the write side buffer in a predetermined amount (transfer packet size), the data transfer to the memory is performed after a certain period of time. Therefore, if a certain amount of time elapses before the transfer packet size (band size) is accumulated and the compressed data in the write buffer is transferred to the memory, the data being compressed will remain in the compressor. There is a possibility that constant image data cannot be transferred to the memory every time, and variations in the first copy time cannot be completely suppressed. Also, in variable-length compression, as in JPEG, a marker called end code EOI (End Of Identify) indicating the end of a file is generally added. In the JPEG standard, anything after the end code EOI is ignored and what is recorded. Therefore, data (redundant data) may exist after the end code EOI. In the prior art, as shown in FIG. 19, the shaded portion is effective compressed data. When reading compressed data from the memory, the entire data area set by the descriptor is read. In the data area set in Fig. 19, the data in the blank portion after the end code EOI other than the hatched portion in Fig. 19 is also read, and the effect of variable-length compression of the image data has been diminished. .

  Therefore, the present invention reduces the time for reading compressed data written in the storage means, prohibits reading unnecessary data, compresses image data, and transfers the compressed data to the storage means. It is an object of the present invention to provide an image processing apparatus, an image processing method, an image processing program, and a recording medium that appropriately perform decompression transfer cooperation for transferring compressed data to the decompression side and shorten the transfer processing time.

  In order to achieve the above-mentioned object, the present invention uses compressed data stored in the storage means after being variable-length compressed with a predetermined data amount as a compression unit, based on a descriptor in accordance with a next data transfer permission signal from the decompression side. When reading from the storage unit for each compression unit and transferring to the decompression side, the compressed data read from the storage unit and written to the buffer is counted, and the specified data whose compressed data size is specified by the descriptor When either the write count end notification output when the size is reached or the next data transfer permission notification is generated, the next descriptor and compressed data are read from the storage means.

  Further, the present invention may be characterized in that the decompression side generates the next data transfer permission signal based on a termination signal added to a termination of the compressed data for each compression unit.

  Further, the present invention waits for the generation of a read count end signal that is output when the count value of the compressed data read from the buffer reaches the specified data size when the write count end notification is generated. The descriptor and the compressed data may be read out.

  Further, the present invention may be characterized in that when the write count end notification is generated, the next descriptor and the compressed data are read after waiting for the next data transfer permission signal to be input.

  Furthermore, the present invention shows that the decompression means has emptied the internal buffer in which the decompression means temporarily stores the compressed data sent from the buffer read control means as the next data transfer permission signal. A buffer empty signal and / or an operation end signal indicating that the decompression process of the compressed data has ended may be output.

  According to the present invention, by monitoring the data amount of the compressed data read from the storage means, it is possible to shorten the read time of the compressed data written in the storage means, and compress the image data to the storage means. The transfer processing time can be shortened by appropriately coordinating the decompression transfer in which the compressed data in the storage means is transferred from the compressed transfer to the decompression side.

The principal part block block diagram of the compound apparatus to which 1st Example of this invention is applied. The detailed block block diagram of RDMAC of an image decompressor. The figure which shows the format structural example of a descriptor. 10 is a flowchart showing descriptor read control processing by a descriptor read control unit of the RDMAC of the image decompressor. The figure which shows the compression descriptor and descriptor of a memory area. The timing diagram of the RDMAC of the image decompressor. FIG. 6 is a timing diagram of a conventional decompression-side RDMAC. The detailed block block diagram of RDMAC of the compound apparatus to which the second embodiment of the present invention is applied. 12 is a flowchart illustrating descriptor read control processing by the DPR read control unit according to the second embodiment. 10 is a flowchart showing processing subsequent to FIG. The figure which shows the compressed data and descriptor of the memory of 2nd Example. The timing chart at the time of malfunction occurrence. The timing diagram of RDMAC of 2nd Example. The detailed block block diagram of RDMAC of the compound apparatus to which the third embodiment is applied. 12 is a flowchart illustrating descriptor read control processing by the DPR read control unit according to the third embodiment. 16 is a flowchart showing processing subsequent to FIG. Timing chart when trouble occurs. The timing chart of RDMAC by 3rd Example. Explanatory drawing of the compression data reading process of the conventional memory.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, since the Example described below is a suitable Example of this invention, various technically preferable restrictions are attached | subjected, However, The range of this invention is unduly limited by the following description. However, not all the configurations described in the present embodiment are essential constituent elements of the present invention.

  1 to 7 are diagrams showing a first embodiment of an image processing device, an image processing method, an image processing program, and a recording medium according to the present invention. FIG. 1 shows an image processing device, an image processing method according to the present invention, 1 is a block diagram of a main part of a composite apparatus 1 to which a first embodiment of an image processing program and a recording medium is applied. FIG.

  In FIG. 1, the multifunction apparatus 1 includes a controller 2 and an engine unit 3, and the controller 2 and the engine unit 3 are connected by a video I / F.

  The engine unit 3 includes a scanner 11 and a plotter 12, reads an image of a document, and prints out an image on a sheet by the plotter 12 based on image data processed by the controller 2. As the scanner 11, for example, an image scanner using a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) is used, and generally includes an ADF (Automatic Document Feeder). ing. A plurality of originals are set in the ADF, and the ADF feeds the set originals one by one to the original reading position of the scanner 11. The scanner 11 scans the document conveyed from the ADF, reads an image of the document with a predetermined resolution, converts the RGB image signal into a digital signal, and outputs it to the controller 2.

  The plotter 12 uses a predetermined printing system, for example, an electrophotographic system or an ink ejection system plotter, and prints and outputs an image on paper in color or monochrome.

  The composite apparatus 1 is not limited to the scanner 11 as an input function of image data. For example, the composite apparatus 1 receives facsimile data by facsimile communication or is sent from an information processing apparatus such as a computer connected to a network. The received image data may be received as input image data. In addition, the composite apparatus 1 not only outputs the image data on the paper by the plotter 12, but also outputs it by facsimile transmission by a facsimile function, an information processing apparatus connected to the network, another composite apparatus, etc. The image data may be transmitted and output.

  The controller 2 includes an ASIC (Application Specific Integrated Circuit) 21, an ASIC 22, a hard disk 23, a CPU (Central Processing Unit) 24, an operation unit 25, a memory 26, and the like, and controls control, drawing, and communication of the composite apparatus 1. At the same time, the operation input from the operation unit 25 is controlled.

  The ASIC 21 is an image processing IC (Integrated Circuit) having hardware elements for image compression / decompression and image processing, and also serves as a bridge for connecting the hard disk 23, the memory 26, and the CPU 24. The ASIC 21 includes an internal register 31, a scanner I / F 32, an image decompressor 33, an image processor 34, and the like. Data such as processing parameters is set in the internal register 31 by the CPU 24.

  The scanner I / F 32 includes a compressor (compression unit) 41, a WDMAC (Write Direct Memory Access Controller) 42, and the like, and compresses image data input from the scanner 11 for each predetermined data amount (compression unit). 41 is subjected to variable-length compression by a variable-length compression method such as JPEG, and DMA-transferred to the memory 26 by the WDMAC 42 without using the CPU 24 to write the compressed data with a reduced data amount. The WDMAC 42 refers to the descriptor (DPR) written on the memory 26 by the CPU 24 and manages the amount of compressed data (code data) to be written to the memory 26 and the address to be written. Memory access to write compressed data.

  The image decompressor 33 includes a decompressor 43, an RDMAC (Read Direct Memory Access Controller) 44, and the like. The RDMAC 44 refers to a descriptor written on the memory 26 by the CPU 24, and does not go through the CPU 24. The compressed data above is read and passed to the decompressor 43. The decompressor (decompression unit) 43 decompresses (decodes) the compressed data read by the RDMAC 44 to the original image data, and outputs the decompressed image data to the image processor 34. Then, when reading data on the memory 26, the RDMAC 44 issues a read command to the memory 26, and then performs a read command pre-throw that issues the next read command without waiting for a read data response to the read command. Reduce memory read time.

  The image processing unit 34 includes an image processing unit 45, a WDMAC 46, and the like. The image processing unit 45 performs predetermined image processing necessary for printing out the image data expanded by the image expansion unit 33, For example, image processing such as error diffusion and gamma conversion is performed. The WDMAC 46 refers to the descriptor written on the memory 26 by the CPU 24, manages the data amount of the image data written to the memory 26 processed by the image processing unit 45, and the address to be written. A memory access is made to the memory 26 to write image data.

  The ASIC 22 is an IC having a function of controlling printing timing with the plotter 12 when image data on the memory 26 is transferred to the plotter 12, and also has a role of a bridge for connecting the memory 26 and the CPU 24. The ASIC 22 has an internal register 47 and a plotter I / F 48, and the plotter I / F 48 has an RDMAC 49. The internal register 47 is set with data such as processing parameters by the CPU 24. When reading the image data on the memory 26, the RDMAC 49 of the plotter I / F 48 performs a read command first throw that issues the next read command without waiting for a read data response after issuing the read command, thereby reducing the memory read time. To shorten.

  The operation unit 25 has a function of accepting an input operation from the user and displaying information to be notified to the user. Operation of a numeric keypad including a mechanical key, a touch panel key, a character input key, a start key, a stop key, etc. In addition to having a key, it has a display unit such as a liquid crystal display (LCD) that displays information input from the operation key, the operating state of the composite apparatus 1, the time, and the like.

  The hard disk 23 stores image data, programs, font data, form data, and the like under the control of the CPU 24. However, the storage means is not limited to the hard disk 23, and is a non-volatile storage capable of storing such information. It may be a storage means, for example, an optical disk or the like.

  The memory (storage means) 26 is constituted by a RAM (Random Access Memory) or the like, and is used as an image data buffer and a compressed data buffer.

  The CPU 24 sets data in the internal registers 31 and 47 of the ASIC 21 and the ASIC 22 according to a program stored in a ROM (Read Only Memory) or the hard disk 23 (not shown), and controls the operation of the controller 2 together with the engine unit 3. The basic processing as the composite apparatus 1 is executed, and the image processing method of the present invention is executed. The CPU 24 also performs memory access arbitration for the ASIC 21 and the ASIC 22.

  The RDMAC (read DMA control means) 44 of the image decompressor 33 has a block configuration as shown in FIG. 2, and includes a DPR read control unit 51, a memory I / F 52, a write toggle control unit 53, and a read toggle control unit 54. Two buffers 55a and 55b, a register 56, and the like are provided.

  The DPR read control unit (descriptor read control means) 51 reads the descriptor (DPR) written by the CPU 24 on the memory 26, reads the descriptor information (SA / SIZE), the read toggle control unit 54, and the write toggle control unit 53. When it is distributed to the memory I / F 52 and, as will be described later, a write count end notification from the write toggle control unit 53 or a next band transfer permission signal (next data transfer permission signal) NEXT from the decompressor 43 is notified. Read access is made to the address described in the NDP of the descriptor. Further, the DPR read control unit 51 controls the number of first throws of the DPR read command of the descriptor based on the availability of the buffers 55a and 55b. That is, when the decompressor 43 detects the termination code EOI indicating the termination of the variable length compressed data, it outputs the next band transfer permission signal NEXT to the read toggle control unit 54 and the DPR read control unit 51 of the RDMAC 44.

  The descriptor has a format configuration as shown in FIG. 3, and is composed of a 4-byte (byte) NDP (Next Descriptor Pointer), SA (Start Address), SIZE, Option, and the like. Written on. SA describes the start address of the compressed data read by the RDMAC 44, and SIZE describes the amount of compressed data to be transferred. In the composite apparatus 1 of this embodiment, since the compressed data is variable length compressed data, the data amount is unknown, but the data size corresponding to the worst compression rate of the compressor 41 is described in SIZE. NDP describes the address of the next descriptor. When NDP = 0, it indicates that there is no next descriptor. In MODE, the mode setting of DMAC is described.

  The memory I / F (reading unit) 52 includes an address generation unit 52a. The address generation unit 52a receives the DPR address (descriptor address) from the DPR read control unit 51 or the line count value from the write toggle control unit 53. Based on the above, an address of the memory 26 to be accessed is generated. The memory I / F 52 issues a read command using the address generated by the address generation unit 52a. Further, the memory I / F 52 transfers read data in response to the issued read command to the DPR read control unit 51 or the write toggle control unit 53.

  The write toggle control unit (buffer write control means) 53 includes a write counter 53a, and the write counter (write count means) 53a counts compressed data to be written to the buffers 55a and 55b. The write toggle controller 53 controls the buffers 55a and 55b for writing the compressed data to toggle based on the write count value that is the count result of the write counter 53a, and writes the compressed data buffers 55a and 55b. The DPR read control unit 51 is notified of the availability of 55a and 55b. The write counter 53a counts down the data amount written to the buffers 55a and 55b with the initial value as SIZE, and outputs (asserts) a write count end notification to the DPR read control unit 51 when the counter value becomes “0”.

  The read toggle control unit 54 includes a read counter 54a that controls the reading of the buffers 55a and 55b and counts the compressed data read from the buffers 55a and 55b. The read counter 54a sets the initial value as SIZE and reads from the buffers 55a and 55b. Count down the amount of compressed data read. During the counting, the read toggle control unit 54 asserts the data valid signal dma_alive output to the decompressor 43. When the counter value becomes “0”, the read toggle control unit 54 negates the data valid signal dma_alive and EOB (End of Block). ) Notify the pulse to the subsequent decompressor 43. Further, when the next band transfer permission signal NEXT is asserted, the read toggle control unit 54 negates the data valid signal dma_alive, and the read count of the read counter 54a becomes “0”. At this time, the EOB pulse is not output to the subsequent stage.

  The buffers 55a and 55b have a buffer capacity for one read command, and have the same number of buffers 55a and 55b as the number of read commands to be thrown forward. The composite apparatus 1 of this embodiment has two buffers 55a and 55b, and the number of read command first throws is two.

  The composite apparatus 1 of this embodiment includes a ROM, an EEPROM (Electrically Erasable and Programmable Read Only Memory), an EPROM, a flash memory, a flexible disk, a CD-ROM (Compact Disc Read Only Memory), and a CD-RW (Compact Disc Rewritable). ), DVD (Digital Versatile Disk), SD (Secure Digital) card, MO (Magneto-Optical Disc), etc., an image processing program for executing the image processing method of the present invention recorded on a computer-readable recording medium By reading and introducing it into a ROM or the like, the compressed data written in the memory 26, which will be described later, is shortened, and the compressed data in the memory 26 is decompressed from the compressed transfer for compressing the image and transferring it to the memory 26. The image which executes the image processing method which shortens the transfer processing time by appropriately coordinating the decompression transfer transferred to 43 It is constructed as an image processing device. This image processing program is a computer-executable program written in a legacy programming language such as assembler, C, C ++, C #, Java (registered trademark) or an object-oriented programming language, and is stored in the recording medium. Can be distributed.

  Next, the operation of this embodiment will be described. The composite apparatus 1 of the present embodiment reads compressed data at high speed while preventing reading of dummy data from the memory 26, compresses image data, and transfers the compressed data to the memory 26. The transfer processing time is shortened by appropriately coordinating the decompression transfer for transferring the data to the decompressor 43.

  That is, when input image data input at a constant speed is variable-length compressed and transferred and stored in the memory 26, when the variable-length compressed data on the memory 26 is read out and decompressed and output, the input image data is variable-length compressed. For the compression transfer processing to transfer to the memory 26, data transfer is performed by giving the right to use the bus preferentially over the decompression transfer processing for reading and expanding the variable length compressed data in the memory 26. Therefore, there is a possibility that the compression transfer cannot overtake the decompression transfer and cannot perform appropriate subsequent processing. The RDMAC 44 reads dummy data (redundant data) in the empty area when there is an empty memory area specified by the descriptor after the end code EOI. Increasing the processing speed is effective for improving the transfer speed.

  Therefore, in the reading of variable length compressed data from the memory 26 by the RDMAC 44, the composite apparatus 1 of this embodiment prevents reading of dummy data and shortens the reading time of compressed data, and performs compression transfer processing and decompression transfer processing. It is linked appropriately to improve the processing speed of the entire transfer process.

  That is, in the image decompressor 33, the RDMAC 44 reads the compressed data on the memory 26 and outputs it to the decompressor 43 by issuing a read command with reference to the descriptor (DPR) on the memory 26. The decompressor 43 decompresses the compressed data. In the RDMAC 44, the DPR read control unit 51 performs the read process of the memory 26, and performs the descriptor read control process as shown in FIG. That is, when the RDMAC 44 is activated, the DPR read control unit 51 loads the initial value descriptor pointer (DPR pointer), which is the address of the first descriptor set by the CPU 24, into the register 56 from the register 56 (step S101). The address of the band set in the initial descriptor pointer (DPR pointer) of the memory 26 is read and set in the internal register (step S102).

  Next, the DPR read control unit 51 sets the address described in the descriptor pointer (DPR pointer) of the initial value in the descriptor address bus (DPR address bus), and sets the descriptor read trigger (DPR read trigger) in the memory I / F 52. ) Is issued (step S104). The memory I / F 52 issues a read command for the descriptor address set in step S103 to the memory 52, and the DPR read control unit 51 waits for a response of descriptor read data (DPR read data) corresponding to the issued read command. (Step S105).

  When receiving the descriptor read data, the DPR read control unit 51 distributes the descriptor information to the necessary internal control unit of the RDMAC 44 (step S106). That is, the DPR read control unit 51 transfers the SA information of the descriptor information to the memory I / F 52 and transfers the SIZE information to the write toggle control unit 53 and the read toggle control unit 54.

  The DPR read control unit 51 holds (latches) the descriptor information (SA1 / SIZE1 / NDP1 / MODE1) in the DPR read control unit 51 (step S107), and notifies the write count end notification or the next band transfer permission signal NEXT. Wait (step S108).

  When receiving the write count end notification or the next band transfer permission signal NEXT notification, the DPR read control unit 51 confirms the NDP of the descriptor information (step S109).

  In step S109, if the NDP of the descriptor information is other than “0”, the DPR read control unit 51 determines that it is not the end of all the compressed descriptors, and sets the address indicated by the NDP in the internal register ( Step S110), returning to step S104, processing is performed in the same manner as described above from the issuance of the descriptor read trigger (DPR read trigger) to the memory I / F 52 (steps S104 to S109).

  In step S109, if the NDP of the descriptor information is “0”, the DPR read control unit 51 determines that all the compressed data is completed, and ends the process.

  That is, as shown in FIG. 5, when the compressed data and descriptor (DPR) are recorded in the memory 26, that is, the data size of the variable-length compressed data is smaller than the data size specified by the descriptor, the terminal code When redundant data exists up to the DPR size after the EOI, as shown in the timing diagram of the RDMAC 44 in FIG. 6, the DPR read control unit 51 detects the termination code EOI at the timing Ta and the next band. The transfer permission signal NEXT is output to the read toggle control unit 54 and the DPR read control unit 51 of the RDMAC 44. When the DPR read control unit 51 receives the next band transfer permission signal NEXT, the descriptor of the next band is indicated by an arrow. Is read (DPR lead). In FIG. 6, A_Data indicates data that the RDMAC 44 reads from the memory 26, and B_Data indicates data that is output from the RDMAC 44 to the decompressor 43.

  Therefore, the RDMAC 44 can prevent reading of dummy data after the end code EOI, and can improve the performance of the read process. At this time, the read toggle control unit 54 negates the data valid signal dma_alive and notifies the decompressor 43 in the subsequent stage of the EOB pulse.

  Conventionally, since the descriptor read control unit detects only the write count end notification from the write toggle control unit, the RDMAC stores dummy data (redundant data) after the end code EOI as shown in FIG. As a result, the effect of variable length compression was diminished.

  As described above, the composite apparatus 1 according to the present embodiment uses the next band transfer permission signal (next data transfer permission signal) from the decompressor 43 to the compressed data stored in the memory 26 by variable length compression using a predetermined data amount as a compression unit. Signal) When the band is read out from the memory 26 for each band (compression unit) in accordance with the descriptor and transferred to the decompressor 43, the write toggle control unit 53 of the RDMAC 44 reads the compressed data of the band read out from the memory 26. When writing to the buffers 55a and 55b and the write counter 53a completes writing of the compressed data to the buffers 55a and 55b, the write completion notification is issued to the DPR read control unit 51, and the descriptor read control unit 51 The compressed data written in 55b is read out and output to the decompressor 43, and the The compressed data written in the files 55a and 55b is counted by the write counter 53a. When the compressed data size counted by the write counter 53a reaches the designated data size designated by the descriptor, a write count end notification is sent to the DPR read control unit 51. When either the write count end notification or the next band transfer permission signal NEXT from the decompressor 43 is input, the DPR read control unit 51 issues the next DPR read trigger to the memory I / F 52. Thus, the descriptor of the next band and the compressed data are read from the memory 26.

  Therefore, by monitoring the data amount of the compressed data read from the memory 26, it is possible to shorten the read time of the compressed data written in the memory 26. From the compression transfer in which the image data is compressed and transferred to the memory 26. The transfer processing time can be shortened by appropriately coordinating the decompression transfer for transferring the compressed data in the memory 26 to the decompressor 43.

  In the composite apparatus 1 of the present embodiment, the decompressor 43 generates the next data transfer permission signal based on the end code EOI added to the end of the compressed data for each compression unit.

  Accordingly, reading of dummy data (redundant data) added after the end code EOI can be prevented, and the reading speed of the compressed data can be further improved.

  8 to 13 are diagrams showing a second embodiment of the image processing apparatus, the image processing method, the image processing program, and the recording medium of the present invention, and FIG. 8 shows the image processing apparatus, the image processing method, It is a principal block block diagram of the compound apparatus 1 to which the second embodiment of the image processing program and the recording medium is applied.

  The present embodiment is applied to a composite apparatus similar to the composite apparatus 1 of the first embodiment. In the description of the present embodiment, the same components as those of the composite apparatus 1 of the first embodiment are used. Are denoted by the same reference numerals, the description thereof will be omitted or simplified, and portions not shown will be described using the reference numerals used in the description of the first embodiment as they are.

  In FIG. 8, an RDMAC (read DMA control means) 60 includes a memory I / F 52, a write toggle control unit 53, a read toggle control unit 54, buffers 55a and 55b, a register 56, and the like similar to the RDMAC 44 of the first embodiment. In addition, a DPR read control unit (descriptor read control means) 61 is provided.

  As in the first embodiment, the read toggle control unit 54 includes a read counter 54a. As described above, the read counter 54a sets the initial value as the data size set in the directory SIZE and uses the buffer 55a. , 55b is counted down by the amount of compressed data read from 55b. The read toggle control unit 54 asserts the data valid signal dma_alive output to the decompressor 43 while the read counter 54a is counting. When the counter value becomes “0”, the read toggle control unit 54 negates the data valid signal dma_alive and EOB. The pulse is notified to the subsequent expander 43. Further, when the next band transfer permission signal NEXT is asserted, the read toggle control unit 54 negates the data valid signal dma_alive, and the read count of the read counter 54a becomes “0”. At this time, the EOB pulse is not output to the subsequent stage.

  The read counter 54 a outputs a read count end notification to the DPR read control unit 61 when the counter value reaches “0” and the count is completed.

  Similar to the DPR read control unit 51 of the first embodiment, the DPR read control unit 61 reads the descriptor written by the CPU 24 on the memory 26 and reads the descriptor information (SA / SIZE) by the read toggle control unit 54, It is distributed to the write toggle control unit 53 and the memory I / F 52, and the write count end notification of the write toggle control unit 53, the read count end notification from the read counter 54a of the read toggle control unit 54, or the next from the expander 43 When the band transfer permission signal NEXT is notified, the address described in the descriptor NDP is read-accessed. Further, the DPR read control unit 61 controls the number of first throws of the DPR read command of the descriptor based on the availability of the buffers 55a and 55b.

  Similarly to the first embodiment, the memory I / F 52 has an address that the address generation unit 52a accesses to the memory based on the DPR address of the DPR read control unit 61 or the write count value of the write toggle control unit 53. Generate a read command using the generated address. The memory I / F 52 transfers the read data from the memory 26 that responds to the read command to the DPR read control unit 61 or the write toggle control unit 53.

  Similar to the first embodiment, the write toggle control unit 53 has a write counter 53a for controlling the writing of the buffers 55a and 55b and counting the data to be written to the buffer, and based on the write count value that is the count result of the write counter 53a. Thus, the compressed data buffers 55a and 55b are toggled to write the compressed data buffers 55a and 55b, and the DPR read controller 51 is notified of the availability of the buffers 55a and 55b. The write counter 53a counts down the data amount written to the buffers 55a and 55b with the initial value as SIZE, and outputs (asserts) a write count end notification to the DPR read control unit 51 when the counter value becomes “0”.

  Next, the operation of this embodiment will be described. In the composite apparatus 1 of this embodiment, the DPR read control unit 61 controls the read access of the descriptor by using the read count end notification from the read counter 54a of the read toggle control unit 54, so that the compressed data in the memory 26 is stored. Even when the data size matches the specified data size of the descriptor, the compressed descriptor is read appropriately.

  That is, the DPR read control unit 61 executes a descriptor read process as shown in FIGS. 9 and 10, the same step number is assigned to the same processing step as the descriptor read processing shown in FIG. 4 of the first embodiment, and the description is simplified. When the RDMAC 60 is activated, the DPR read control unit 61 loads the initial value descriptor pointer (DPR pointer), which is the address of the first descriptor set by the CPU 24, into the register 56 from the register 56, as shown in FIG. Then, the address of the band set in the descriptor descriptor (DPR pointer) of the initial value in the memory 26 is read and set in the internal register (step S102). Next, the DPR read control unit 61 sets the address described in the descriptor pointer (DPR pointer) of the initial value in the descriptor address bus (DPR address bus), and sets the descriptor read trigger (DPR read trigger) in the memory I / F 52. ) Is issued (step S104). The memory I / F 52 issues a read command for the descriptor address set in step S103 to the memory 52, and the DPR read control unit 61 waits for a response of descriptor read data (DPR read data) corresponding to the issued read command. (Step S105). When the DPR read control unit 61 receives the descriptor read data, the DPR read control unit 61 distributes the descriptor information to necessary internal control units of the RDMAC 60 (step S106), and the descriptor information (SA1 / SIZE1 / NDP1 / MODE1) is stored in the DPR read control unit 61. Is held (latched) (step S107).

  When the DPR read control unit 61 latches the descriptor information, as shown in FIG. 10, the DPR read control unit 61 waits until receiving either the write count end notification or the next band transfer permission signal NEXT notification (step S201), and the next band transfer permission signal. When there is a notification of NEXT, the NDP of the descriptor information is confirmed (step S109).

  If there is a write count end notification in step S201, the DPR read control unit 61 determines that the compressed data for SIZE, that is, the compressed data for the designated data size specified by the descriptor has been read from the memory 26. In response to the read count end notification from the read counter 54a (step S202), when the read count end notification is received, it is determined that the buffers 55a and 55b are empty, and the compressed data of the next band is read. The NDP of the descriptor information is confirmed (step S109).

  In step S109, if the NDP of the descriptor information is other than “0”, the DPR read control unit 51 determines that all the compressed descriptors are not terminated, and sets the address indicated by the NDP in the internal register ( Step S110), returning to step S104 in FIG. 9, processing is performed in the same manner as described above from the issuance of the descriptor read trigger (DPR read trigger) to the memory I / F 52 (steps S104 to S107, S201, S202, S109).

  In step S109, if the NDP of the descriptor information is “0”, the DPR read control unit 51 determines that all the compressed data is completed, and ends the process.

  That is, as shown in FIG. 11, when the compressed data and descriptor (DPR) are recorded in the memory 26, that is, the data size specified by the descriptor and the data size of the variable length compressed data are the same, and the end code When there is no redundant data after the EOI, as shown in FIG. 12, the first copy time can be shortened if only dummy data (redundant data) after the end code EOI of the compressed data is not read. If the final data of the band 1 of the compressed data is the end code EOI, there is a possibility of jumping to the next band (band 3) while the band 2 is being read.

  However, as described above, when the DPR read control unit 61 receives a write count end notification from the read counter 54a of the read toggle control unit 54 in step S201, as shown in FIG. If the signal NEXT is not asserted, the next band descriptor is not read until the buffers 55a and 55b become empty by waiting for a read count end notification in step S202. Therefore, even if the final data of each band of the compressed data is the termination code EOI, the reading speed of the compressed data from the memory 26 can be improved and the jump to the next band during the reading is prevented. Therefore, it is possible to read appropriate compressed data while shortening the first copy time.

  As described above, in the composite apparatus 1 of this embodiment, the read toggle control unit 54 counts the compressed data read from the buffers 55a and 55b, and sets the count value to the designated data size (SIZE) designated by the descriptor. Then, a read counter 54a that outputs a read count end signal to the DPR read control unit 61 is provided. When the DPR read control unit 61 receives a write count end notification, the read count end signal is input. Waiting for the next descriptor and compressed data to be read.

  Therefore, when the final data of each band of the compressed data of the compression unit is the end code EOI, it is possible to appropriately prevent jumping to the next band during the reading of the compressed data, and shorten the first copy time. However, an abnormal image can be generated by reading appropriate compressed data.

  14 to 18 are diagrams showing a third embodiment of the image processing apparatus, the image processing method, the image processing program, and the recording medium of the present invention. FIG. 14 shows the image processing apparatus, the image processing method, It is a principal block block diagram of the compound apparatus 1 to which the third embodiment of the image processing program and the recording medium is applied.

  The present embodiment is applied to a composite apparatus similar to the composite apparatus 1 of the first embodiment. In the description of the present embodiment, the same components as those of the composite apparatus 1 of the first embodiment are used. Are denoted by the same reference numerals, the description thereof will be omitted or simplified, and portions not shown will be described using the reference numerals used in the description of the first embodiment as they are.

  In FIG. 14, an RDMAC (read DMA control means) 70 includes a memory I / F 52, a write toggle control unit 53, buffers 55a and 55b, a register 56, and the like similar to the RDMAC 44 of the first embodiment, and also DPR read. A control unit (descriptor read control means) 71 and a read toggle control unit (buffer read control means) 72 are provided.

  The busy signal is input from the decompressor 43 to the DPR read control unit 71 and the read toggle control unit 72, and this busy signal is a buffer empty signal indicating an empty state of the internal buffer of the decompressor 43. When the internal buffer becomes empty, it becomes “0”. The DPR read control unit 71 and the read toggle control unit 72 receive the next band transfer permission signal NEXT from the decompressor 43 as in the case of the first embodiment. Note that the next data transfer permission signal output from the decompressor 43 is not limited to the busy signal, and may be an operation end signal indicating the end of the operation of the decompressor 43.

  The DPR read control unit 71 reads the descriptor and distributes the descriptor information (SA / SIZE) to the read toggle control unit 54, the write toggle control unit 53, and the memory I / F 52. When the write count end notification, busy signal, or next band transfer permission signal NEXT is notified from the write toggle control unit 53, the DPR read control unit 71 performs read access to the address described in the NDP of the descriptor. . Further, the DPR read control unit 71 controls the number of first throws of the DPR read command of the descriptor based on the availability of the buffers 55a and 55b.

  The memory I / F 52 and the light toggle control unit 53 are the same as in the first embodiment.

  As in the first embodiment, the read toggle control unit 72 includes a read counter 54a. As described above, the read counter 54a sets the initial value as the data size set in the directory SIZE and uses the buffer 55a. , 55b is counted down by the amount of compressed data read from 55b. The read toggle control unit 54 asserts the data valid signal dma_alive output to the decompressor 43 while the read counter 54a is counting. When the counter value becomes “0”, the read toggle control unit 54 negates the data valid signal dma_alive and EOB. The pulse is notified to the subsequent expander 43. Further, when the next band transfer permission signal NEXT is asserted, the read toggle control unit 54 negates the data valid signal dma_alive, and the read count of the read counter 54a becomes “0”. At this time, the EOB pulse is not output to the subsequent stage.

  Next, the operation of this embodiment will be described. The composite apparatus 1 of this embodiment performs read control of the next band based on the busy signal from the decompressor 43.

  That is, the DPR read control unit 71 executes descriptor read processing as shown in FIGS. In FIG. 15 and FIG. 16, the same step number is assigned to the same processing step as the descriptor read processing shown in FIG. 4 of the first embodiment, and the description is simplified. When the RDMAC 70 is activated, the DPR read control unit 71 loads the initial descriptor pointer (DPR pointer), which is the address of the first descriptor set by the CPU 24, into the register 56 from the register 56, as shown in FIG. Then, the address of the band set in the descriptor descriptor (DPR pointer) of the initial value in the memory 26 is read and set in the internal register (step S102). Next, the DPR read control unit 71 sets the address described in the descriptor pointer (DPR pointer) of the initial value in the descriptor address bus (DPR address bus), and sets the descriptor read trigger (DPR read trigger) in the memory I / F 52. ) Is issued (step S104). The memory I / F 52 issues a read command of the descriptor address set in step S103 to the memory 52, and the DPR read control unit 71 waits for a response of descriptor read data (DPR read data) corresponding to the issued read command. (Step S105). When the DPR read control unit 71 receives the descriptor read data, the DPR read control unit 71 distributes the descriptor information to the necessary internal control unit of the RDMAC 70 (step S106), and the descriptor information (SA1 / SIZE1 / NDP1 / MODE1) is stored in the DPR read control unit 71. Is held (latched) (step S107).

  When the descriptor information is latched, the DPR read control unit 71 waits to receive either the write count end notification or the next band transfer permission signal NEXT notification as shown in FIG. When the signal NEXT is notified, the NDP of the descriptor information is confirmed (step S109).

  In step S301, if there is a write count end notification, the DPR read control unit 71 waits for the busy signal to become “0” (step S302), and if the busy signal becomes “0”, the internal buffer of the decompressor 43 In order to read the compressed data of the next band, the NDP of the descriptor information is confirmed (step S109).

  In step S109, if the NDP of the descriptor information is other than “0”, the DPR read control unit 51 determines that all the compressed descriptors are not terminated, and sets the address indicated by the NDP in the internal register ( Step S110), returning to Step S104 in FIG. 15, processing is performed in the same manner as described above from the issuance of the descriptor read trigger (DPR read trigger) to the memory I / F 52 (Steps S104 to S107, S301, S302, S109).

  In step S109, if the NDP of the descriptor information is “0”, the DPR read control unit 51 determines that all the compressed data is completed, and ends the process.

  That is, as shown in FIG. 11, the compressed data and the descriptor (DPR) are recorded in the memory 26, the data size specified by the descriptor and the data size of the variable length compressed data are the same, and the end code EOI If there is no redundant data thereafter, as shown in FIG. 17, the first copy time can be shortened if only dummy data (redundant data) after the end code EOI of the compressed data is not read. If the final data of the compressed data band 1 is the termination code EOI and the detection of the termination code EOI is delayed due to the buffer delay, there is a possibility that the band 2 may jump to the next band (band 3) in the middle of reading.

  However, as described above, even if the DPR read control unit 71 receives the write count end notification from the write toggle control unit 53 as shown in FIG. By waiting for the signal to become “0”, reading of the next band descriptor is prevented until the internal buffer of the decompressor 43 becomes empty. Therefore, even if the final data of each band of the divided compressed data is the end code EOI and an error occurs in the detection timing of the end code EOI as shown in FIG. 18, the reading speed of the compressed data from the memory 26 is increased. In addition to being able to improve, it is possible to prevent jumping to the next band in the middle of reading, and appropriate compressed data can be read while shortening the first copy time.

  As described above, in the composite apparatus 1 of this embodiment, when the DPR read control unit 61 receives the write count end notification from the write counter 53a of the write toggle control unit 53, the next data transfer permission signal is output from the decompressor 43. Waiting for input, the next descriptor and compressed data are read.

  Therefore, after the operation of the decompressor 43 is confirmed, the descriptor of the next band can be read. Even when the final data of the final band is the end code EOI, an abnormal image is generated. It can be prevented appropriately.

  Further, in the multifunction apparatus 1 of this embodiment, the decompressor 43 indicates that the internal buffer for temporarily storing the compressed data sent from the read toggle control unit 54 as the next data transfer permission signal is empty. A (buffer empty) signal or / and an operation end signal indicating that the decompression process of the compressed data has been completed are output.

  Therefore, it is possible to appropriately determine whether or not the decompressor 43 can process the next compressed data, read the descriptor of the next band, and the final data of the last band is the end code. Even in the case of EOI, it is possible to appropriately prevent the occurrence of an abnormal image.

  The invention made by the present inventor has been specifically described based on the preferred embodiments. However, the present invention is not limited to that described in the above embodiments, and various modifications can be made without departing from the scope of the invention. It goes without saying that it is possible.

  The present invention relates to an image processing apparatus, an image processing method, an image processing program, and a recording apparatus, such as a copying apparatus and a composite apparatus, which decompress and output the compressed data in the memory after the input image data is temporarily compressed in variable length and stored in the memory It can be used as a medium.

DESCRIPTION OF SYMBOLS 1 Compound apparatus 2 Controller 3 Engine part 11 Scanner 12 Plotter 21, 22 ASIC
23 Hard disk 24 CPU
25 Operation Unit 26 Memory 31 Internal Register 32 Scanner I / F
33 Image Expander 34 Image Processor 41 Compressor 42 WDMAC
43 Expander 44 RDMAC
45 Image processing unit 46 WDMAC
47 Internal register 48 Plotter I / F
49 RDMAC
51 DPR read controller 52 Memory I / F
52a Address generation unit 53 Write toggle control unit 53a Write counter 54 Read toggle control unit 54a Read counter 55a, 55b Buffer 56 Register 60 RDMAC
61 DPR read control unit 70 RDMAC
71 DPR lead control unit 72 Lead toggle control unit

JP 2009-33428 A

Claims (8)

The read DMA control means converts the compressed data stored in the compression means by variable-length compressing the image data input for each compression unit as a compression unit into a single compressed data by the compression means, In an image processing apparatus that reads out each compression unit based on a descriptor of the storage unit in accordance with a next data transfer permission signal that permits transfer of next data from a decompression unit that decompresses compressed data, and transfers the compressed data to the decompression unit.
The read DMA control means includes:
Read means for reading out the descriptor and the compressed data of the compression unit from the storage means;
Descriptor read control means for controlling reading of the descriptor and the compressed data from the storage means by the reading means;
A plurality of buffers for temporarily storing the compressed data of the compression unit read from the storage unit by the reading unit;
Buffer write control means for controlling writing of the compressed data of the compression unit read by the reading means to the buffer and issuing a write completion notification when the writing of the compressed data to the buffer is completed;
A buffer read control means for reading the compressed data written in the buffer and outputting it to the decompression means;
The buffer write control unit counts the compressed data written to the buffer, and outputs a write count end notification to the descriptor read control unit when the compressed data size reaches the specified data size specified by the descriptor. And a light counting means,
The descriptor read control means reads the next descriptor and the compressed data when the write count end notice or the next data transfer permission notice is inputted.   The image processing apparatus according to claim 1, wherein the decompressing unit generates the next data transfer permission signal based on a termination signal added to a termination of the compressed data for each compression unit. The buffer read control means includes read count means for counting the compressed data read from the buffer and outputting a read count end signal to the descriptor read control means when the count value reaches the specified data size. ,
The descriptor read control means, when the write count end notification is input, waits for the read count end signal to be input, and reads the next descriptor and the compressed data. The image processing apparatus according to claim 1 or 2.   When the write count end notification is input, the descriptor read control means waits for the next data transfer permission signal to be input, and reads the next descriptor and the compressed data. The image processing apparatus according to claim 1.   The decompression means uses, as the next data transfer permission signal, a buffer empty signal indicating that the internal buffer for temporarily storing the compressed data sent from the buffer read control means by the decompression means has become empty, or / The image processing apparatus according to claim 4, wherein an operation end signal indicating that the decompression process of the compressed data has been completed is output. A read DMA control processing step that compresses variable length compressed image data input to each compression unit into a single compressed data in a compression processing step with a predetermined data amount as a compression unit, and transfers the stored data to a storage means. Is read out for each compression unit based on the descriptor of the storage means in accordance with a next data transfer permission signal permitting transfer of the next data from the decompression processing step for decompressing the compressed data, and transferred to the decompression processing step. A processing method,
The read DMA control processing step includes:
A read processing step of reading the descriptor and the compressed data of the compression unit from the storage means;
A descriptor read control processing step for controlling reading of the descriptor and the compressed data from the storage means by the read processing step;
A buffer write control processing step for controlling writing of the compressed data of the compression unit read by the reading processing step to a plurality of buffers and issuing a write completion notification when the writing of the compressed data to the buffer is completed; ,
A buffer read control processing step of reading out the compressed data written in the buffer and outputting it to the decompression processing step;
The buffer write control processing step counts the compressed data written to the buffer, and when the compressed data size reaches the specified data size specified by the descriptor, a write count end notification is sent to the descriptor read control processing step. And a light count processing step for outputting,
The descriptor read control processing step reads the next descriptor and the compressed data when the write count end notification or the next data transfer permission notification is input. The read DMA control process is a process in which the compressed data stored in the storage unit is compressed by variable-length compression into a single compressed data by compressing the image data input for each compression unit with a predetermined data amount as a compression unit. An image processing program that reads out each compressed unit based on a descriptor of the storage unit and transfers it to the decompression process in accordance with a next data transfer permission signal that permits transfer of the next data from the decompression process that decompresses the compressed data. And
On the computer,
As the read DMA control process,
Read processing for reading out the descriptor and the compressed data of the compression unit from the storage means;
A descriptor read control process for controlling reading of the descriptor and the compressed data from the storage means by the read process;
A buffer write control process for controlling writing of the compressed data of the compression unit read by the reading process to a plurality of buffers and issuing a write completion notification when the writing of the compressed data to the buffer is completed;
A buffer read control process for reading the compressed data written in the buffer and outputting the compressed data to the decompression process;
The buffer write control process counts the compressed data written to the buffer, and outputs a write count end notification to the descriptor read control process when the compressed data size reaches the specified data size specified by the descriptor. Write count processing,
And execute
In the descriptor read control processing, when the write count end notification or the next data transfer permission notification is input, the image processing program causes the next descriptor and the compressed data to be read.   A computer-readable recording medium on which the image processing program according to claim 7 is recorded.

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