JP2018098730A - Image data transfer system and transmission method of image data - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce load of image data on a reception side.SOLUTION: An image data transfer system (Ga) comprises: a transmission device (G1) that processes image data in a block unit, divides each block after image processing into one or a plurality of packs so that a data amount of one pack becomes a target data amount, and transmits each divided pack through a network (G3); and a reception device (G2) that receives each pack transmitted from the transmission device through the network, generates the block by connecting each received pack, processes the image of each generated block, and generates the image data formed by each block after the image processing. The transmission device continuously transmits all packs in the same block to the reception device. The reception device generates the block by connecting all packs in the same block continuously transmitted from the transmission device.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an image data transfer system and an image data transfer method.

  Some image forming apparatuses such as printers and copiers are divided into an apparatus for processing and storing image data by image processing, and an apparatus for forming an image on a sheet based on the image data. Some have a role to play. The former device is called the controller, and the latter device is called the engine. The controller and the engine are connected via a network, and the image data is transferred from the controller to the engine via this network.

  In order to speed up image formation, it is common to perform compression processing on image data during transfer (see, for example, Patent Documents 1 to 4). On the transmission side, the compressed image data is divided into a plurality of packs so that the amount of transfer data per unit time is equal to or less than the network prescribed value, and each pack is transmitted in line units. On the receiving side, each pack is received and decompressed. Since decompression is performed in units of a certain area, the received pack is temporarily held in a line memory or the like until all the packs for the line in the certain area are received. And the burden on the receiving side is large.

  As the network environment expands and grows, the number of controllers and engines connected via the network is increasing. Combinations of controllers and engines with various performances are assumed, but not all engines have memory performance that can hold image data sent from the controllers.

  In the past, attempts have been made to improve the compression processing method for increasing the transfer rate. However, as long as each pack is transmitted in a time-sharing manner in units of lines, the burden on the receiving side cannot be reduced by improving the compression processing method. .

Japanese Patent Laying-Open No. 2015-130071 JP 2009-33427 A JP 2005-204335 A JP2015-170994A

  An object of the present invention is to reduce the burden on the receiving side of image data.

According to the invention of claim 1,
Image data is processed in block units, and each block after the image processing is divided into one or a plurality of packs so that the data amount of one pack becomes the target data amount, and each divided pack is transmitted via a network. A transmitting device for transmitting
Each pack transmitted from the transmission device via the network is received, and the received packs are connected to generate a block, each generated block is subjected to image processing, and each block after the image processing is processed. A receiving device for generating image data,
The transmitting device continuously transmits all packs in the same block to the receiving device,
An image data transfer system is provided in which the receiving device generates the block by concatenating all packs in the same block transmitted continuously from the transmitting device.

According to invention of Claim 2,
2. The image data transfer system according to claim 1, wherein the transmission apparatus generates a block having a target data amount by performing image processing that is completed for each block at one time.

According to invention of Claim 3,
3. The image data according to claim 1, wherein the transmission device simultaneously generates a plurality of different blocks after image processing by performing independent image processing for each of the blocks. 4. A transfer system is provided.

According to invention of Claim 4,
The transmitting device simultaneously transmits the packs of the different blocks;
4. The image data transfer system according to claim 1, wherein the receiving device receives the pack of the plurality of different blocks at the same time.

According to the invention of claim 5,
5. The image data according to claim 1, wherein the reception device generates a block having a target data amount by performing image processing that is completed for each block at one time. A transfer system is provided.

According to the invention of claim 6,
6. The image data transfer system according to claim 1, wherein the receiving device generates a plurality of different blocks simultaneously by performing independent image processing for each of the blocks.

According to the invention of claim 7,
The transmission device performs compression processing as the image processing, and the amount of data transferred per unit time for each block after the compression processing is equal to or less than the amount of data per unit time that can be transferred by the network. Dividing into one or more packs,
7. The image data transfer system according to claim 1, wherein the receiving device performs decompression processing as the image processing, and generates a block having an original data amount before the compression processing. Is provided.

According to the invention described in claim 8,
The image data transfer system according to claim 7, wherein the compression process is a BTC compression process or a degeneracy compression process.

According to the invention of claim 9,
A plurality of transfer units that transfer image data of a plurality of colors at the same time are provided, and when transferring single-color image data, two or more transfer units among the plurality of transfer units are used for transfer. An image data transfer system according to any one of claims 1 to 8 is provided.

According to the invention of claim 10,
The image data transfer system according to claim 1, wherein the network is a network that serially transfers the image data.

According to the invention of claim 11,
The image data transfer system according to claim 1, wherein the network standard is V-by-One (registered trademark).

According to the invention of claim 12,
In the transmission device,
Image processing the image data in units of blocks;
Dividing each block after the image processing into one or a plurality of packs so that one pack has a constant data amount;
Transmitting each of the divided packs via a network;
In the receiving device,
Receiving each pack transmitted from the transmitting device via the network;
Concatenating each received pack to generate a block, and image processing each generated block;
Generating image data consisting of each block after the image processing,
In the transmitting step, all packs in the same block are continuously transmitted to the receiving device,
In the receiving step, an image data transfer method is provided in which all the packs in the same block continuously transmitted from the transmission device are connected to generate the block.

  According to the present invention, it is possible to reduce the burden on the image data receiving side.

It is a block diagram which shows the main structures of the image data transfer system of the 1st Embodiment of this invention. It is a figure which shows the example of 1 block of each image data before a compression process, after a compression process, and after a compression process. It is a figure which shows the data structural example of 1 block after the compression process. It is a figure which shows an example of the template used for prediction of a binary pattern. It is a figure which shows the input order of image data. It is a figure which shows the production | generation order of the block after a compression process. It is a figure which shows the example of a pack of 2 pixels x 4 lines. It is a figure which shows the data structure of each pack transmitted per unit time. It is a figure which shows the transfer order of the image data after a compression process. It is a figure which shows the production | generation order of the block after a compression / decompression process. It is a time chart at the time of image data transmission. It is a block diagram which shows the structure of the image data transfer system of 2nd Embodiment. It is a figure which shows each pack transferred in the transfer unit of each color. It is a block diagram which shows the structure of the image data transfer system of 3rd Embodiment. It is a figure which shows each pack transferred in the transfer unit of 2 colors. It is a figure which shows the data structure of each pack transmitted per unit time. It is a time chart at the time of image data transmission. It is a figure which shows the transmission order of each pack expanded and divided | segmented in the subscanning direction. It is a figure which shows the transmission order of each pack expanded and divided | segmented in the main scanning direction. It is a block diagram which shows the structure of the image data transfer system of the comparative example 1. It is a figure which shows each pack transmitted from the transfer unit of each color. FIG. 10 is a diagram illustrating a transfer order of image data after a compression process in Comparative Example 1. It is a time chart at the time of image data transmission. It is a block diagram which shows the structure of the image data transfer system of the comparative example 2. It is a figure which shows each pack transmitted by the transfer unit of 2 colors. It is a time chart at the time of image data transmission. It is a block diagram which shows the structure of the image data transfer system of the comparative example 3. It is a figure which shows each pack transmitted by the transfer unit of 2 colors. It is a time chart at the time of image data transmission.

  Embodiments of an image data transfer system and an image data transfer method according to the present invention will be described below with reference to the drawings.

[First Embodiment]
FIG. 1 shows the main configuration of the image data transfer system Ga according to the first embodiment of the present invention for each function.
As shown in FIG. 1, the image data transfer system Ga includes a transmission device G1 that transmits image data via a network G3, and a reception device G2 that receives image data transmitted from the transmission device G1 via the network G3. , And is configured.

  The network G3 is not particularly limited as long as it can be used for transferring image data. However, it is preferable to use a network for serial transfer as the network G3 because the transfer speed can be increased. Further, from the viewpoint of increasing the transfer speed, reducing costs, etc., it is preferable to use VbyOne (registered trademark) as the standard of the network G3.

The transmission device G1 performs image processing on the image data in units of blocks, and divides each block after the image processing into one or a plurality of packs so that the data amount of one pack becomes the target data amount. Each pack is transmitted via the network G3.
The receiving device G2 receives each pack transmitted from the transmitting device G1 via the network G3, concatenates the received packs to generate blocks, performs image processing on each generated block, and performs post-image processing. Image data consisting of each block is generated.

  As block-unit image processing performed by the transmission device G1 and the reception device G2, BTC (Block Truncation Coding) compression processing (BTC decompression processing), compression / decompression processing (degeneration / decompression processing), and block dither matrix are used. Examples thereof include screen processing that is binarized or multi-valued in units. In particular, since the transfer rate is improved, BTC compression processing and compression compression processing are preferable, and compression compression processing with high compression rate and high image reproducibility is more preferable.

As the image processing, it is preferable to perform image processing which is completed for each block at once to generate a block having a target data amount.
Thereby, image data for one block can be generated at a time. Further, the data amount of one block can be adjusted in accordance with the data amount that can be transferred per unit time.

In addition, it is preferable to simultaneously generate a plurality of different blocks after image processing by performing independent image processing for each block as the image processing.
As a result, if the network G3 is less than the amount of data that can be transferred per unit time, the image data of a plurality of different blocks can be transferred simultaneously, and the transfer rate is improved.

  The BTC compression process, the degeneracy compression process, the screen process, and the like given as an example of the image process are all image processes that are completed collectively for each block, and are independent image processes for each block.

[BTC compression processing]
In the BTC compression process, each pixel of the image data is divided in units of blocks, and each pixel value in the block is encoded using the maximum value Max and the minimum value min of the pixel value in each divided block. For example, when an 8-bit pixel value is encoded to obtain a 2-bit pixel value, the following thresholds THa1 to THa3 are calculated from the maximum value Max and the minimum value min. When each pixel value in the block is min or more and less than THa1, it is encoded as 00, when THa1 or more and less than THa2, it is encoded as 01, and when THa2 or more and less than THa3, it is encoded as 11.
THa1 = min + (Max−min) × 1/6
THa2 = min + (Max−min) × 3/6
THa3 = min + (Max−min) × 5/6

[BTC extension processing]
In the BTC decompression process, each pixel value in the block is decoded using the 8-bit maximum value Max and the minimum value min used at the time of compression. For example, if the encoded 2-bit pixel value is 00, it is min, if it is 01, min + (Max-min) × 1/3, if 10 it is min + (Max-min) × 2/3, 11 Decoding to Max can obtain an 8-bit pixel value.

[Degenerate compression processing]
The degeneracy compression process is a block unit compression process combined with resolution conversion. As the compression / decompression process, methods described in Japanese Patent Nos. 4424404 and 5029560 can be used.

FIG. 2 shows an example of one block of each image data before the compression process, after the compression process, and after the compression / decompression process.
As shown in FIG. 2, the original image data having a resolution of 1200 dpi, each pixel having 8 bits of data, is subjected to compression compression processing in units of blocks of 8 pixels × 8 lines, and each pixel having a pixel value of 4 bits, having a resolution of 600 dpi. By generating a block of 4 pixels × 4 lines, the data amount of one block can be reduced from 512 bits to 64 bits. Furthermore, when this block of 4 pixels × 4 lines is degenerated and expanded to generate a block of 8 pixels × 8 lines with a resolution of 1200 dpi, each pixel having an 8-bit pixel value, a block having the same data amount as the original image data is generated. Can be restored.

  As shown in FIG. 2, when 8 pixels × 8 lines are set as a block unit, the image data is divided into blocks of 8 pixels × 8 lines in the same way as the BTC compression process at the time of the compression process. The maximum value Max and the minimum value min are extracted. Further, each block is divided in units of 2 pixels × 2 lines, and it is determined whether each divided 2 pixels × 2 lines is a halftone area or a high resolution area. This 2 pixel × 2 line unit is one pixel unit after the compression process. 2 pixels × 2 lines that are halftone areas are encoded in the same manner as the BTC compression process, and 2 pixels × 2 lines that are high resolution areas are encoded by binary patterning to obtain 2-bit pixel values.

The halftone area is an area that satisfies any of the following conditions (1) to (4). THa1 and THa3 may be calculated by the above formulas in the same manner as in the BTC compression process.
(1) There are at least one pixel having a pixel value greater than THa1 and not more than THa3 in 2 pixels × 2 lines. (2) All pixel values of 2 pixels × 2 lines are not more than THa1. (3) 2 pixels All pixel values of × 2 lines exceed THa3. (4) The average value of each pixel value of 2 pixels × 2 lines that satisfies Max-min <T (0 ≦ T ≦ 255) is calculated. The pixel value of one pixel after the compression compression process is encoded by threshold values THa1 to THa3 as in the BTC compression process.

  Further, the high resolution area is an area in which pixels of THa1 or lower and pixels of THa3 or higher are mixed in 2 pixels × 2 lines. By converting a pixel value equal to or less than THa1 in 2 pixels × 2 lines to 0 and a pixel value equal to or greater than THa3 to 1, a 2 pixels × 2 line can be converted into a binary pattern. The number of pixels with a pixel value of 1 in 2 pixels × 2 lines in a binary pattern is encoded as 00 when it is 1, 01 or 10 when it is 2, and 11 when it is 3.

  1-bit identification data indicating whether each of 4 pixels × 4 lines is a halftone area or a high-resolution area at the top of the encoded 2-bit pixel value, and the 8-bit maximum value Max and minimum at the bottom Each 1-bit of the value min is incorporated, and a block of 4 pixels × 4 lines in which 1 pixel has 4-bit data is generated.

FIG. 3 shows an example of the data configuration of one block after the compression process.
As shown in FIG. 3, when a block of 4 pixels × 4 lines after the compression process is represented as a data layer of bit positions [3] to [0], the most significant bit position [4 pixels × 4 lines [ 3] is the 1-bit identification data flag of each pixel. In the bit positions [2] and [1], the encoded 2-bit pixel value bij is located. In the lowest bit position [0], a maximum value Max of 8 bits and a minimum value min of 1 bit are positioned in 4 pixels × 4 lines. In FIG. 3, Max [0] to Max [7] and min [0] to min [7] represent 1 bit of 0 to 7 bits of the maximum value Max and the minimum value min, respectively.

[Degeneration / decompression processing]
At the time of the compression / decompression process, the maximum value Max and the minimum value min of 8 bits are acquired from the bit position [0] of the block of 4 pixels × 4 lines after the compression process. Also, the pixel whose identification data flag indicates a halftone area is decoded in the same manner as the BTC decompression process, and the obtained 8-bit pixel value is assigned as each pixel value of 2 pixels × 2 lines. A pixel whose identification data flag indicates a high-resolution area is decoded by predicting a binary pattern at the time of compression to obtain an 8-bit pixel value.

Prediction of a binary pattern can be performed using a template.
FIG. 4 shows an example of a template used for predicting a binary pattern of a pixel having a 2-bit pixel value of 00. In FIG. 4, X1 to X3 indicate the classification of each template, and the number on the upper left of each template indicates the identification number of the template.

  As shown in FIG. 4, each template is associated with a predicted binary pattern of 2 pixels × 2 lines. A pixel having a pixel value of 00 is compared with each template, and it is determined that the pixel at the position of C or M in the template matches the template that satisfies the following condition around the pixel. By converting 1 in the binary pattern of 2 pixels × 2 lines corresponding to the matching template to the maximum value Max and 0 to the minimum value min, an 8-bit pixel value of 2 pixels × 2 lines after decoding is obtained. Can do.

(Conditions for pixel at position C)
(1) It is a pixel in the halftone area. (2) The density difference | C _den −bij _Max | between the pixel at the position C and the pixel to be decoded is less than the threshold THc (conditions for the pixel at the position M)
(1) A pixel in the high resolution area (2) Density difference | M _Max −bij _Max | between the pixel at the position M and the pixel to be decoded is less than the threshold THm

Note that C _den is an 8-bit pixel value obtained by decoding the encoded 2-bit pixel value of the pixel at the position C. M _Max is the 8-bit maximum value Max of the block to which the pixel at the position of M belongs. bij _Max is the 8-bit maximum value Max of the block to which the pixel to be decoded belongs.
The thresholds THc and THm are thresholds for determining whether the density difference is small, and can be arbitrarily set, for example, THc = 30, THm = 35, and the like.

  Hereinafter, as image processing, a processing procedure in a case where the transmission device G1 performs compression / decompression processing and the reception device G2 performs compression / decompression processing will be described.

[Transmitter]
As illustrated in FIG. 1, the transmission device G1 includes an input unit 11, an image processing unit 12, a division unit 13, and a transmission unit 14.

The input unit 11 inputs image data in units of blocks to the image processing unit 12.
When the block unit is 8 pixels × 8 lines, the input unit 11 includes three FIFO (First In First Out) 110 connected in cascade as shown in FIG. 12 is input.

FIG. 5 shows the input order of image data.
As shown in FIG. 5, the image data of the 0th and 1st lines, the 2nd and 3rd lines, the 4th and 5th lines, the 6th and 7th lines in the sub-scanning direction y are respectively delayed by three FIFOs 110 and simultaneously imaged. Input to the processing unit 12. When the end of the main scanning direction x is reached, all the pixels can be input in units of blocks by shifting eight lines in the sub-scanning direction y and repeating the same input from the first pixel in the main scanning direction x.

  The image processing unit 12 subjects the image data input from the input unit 11 to a block-by-block compression process, and generates each block after the compression process.

FIG. 6 shows the generation order of blocks after the compression process.
As shown in FIG. 6, each block of 4 pixels × 4 lines is sequentially generated in the main scanning direction x, and when reaching the end of the main scanning direction x, four lines are shifted in the sub-scanning direction y to similarly generate blocks. repeat.

The dividing unit 13 divides each block after the compression processing generated by the image processing unit 12 into one or a plurality of packs.
The dividing unit 13 divides the data so that the data amount of one pack becomes the target data amount. By setting the target data amount to be equal to or less than the data amount per unit time that can be transferred by the network G3, it is possible to transmit image data with a prescribed data amount. For example, when the amount of data that can be transferred per unit time of the network G3 is 40 bits and the amount of image data of 4 pixels × 4 lines after image processing is 64 bits, if the data is equally divided into two or more, one pack of data The amount can be 40 bits or less.

FIG. 7 shows an example of a pack divided in units of 2 pixels × 4 lines.
As shown in FIG. 7, the dividing unit 13 outputs two packs obtained from the same block by the division as pack streams in order of numbers (1) and (2). Since the data amount of one pack is 32 bits, a 32-bit area is used out of 40 bits that can be transferred on the network G3.

The transmitting unit 14 transmits each pack divided by the dividing unit 13 to the receiving device G2 via the network G3, one pack per unit time.
At the time of transmission, the transmission unit 14 continuously transmits all packs in the same block to the reception device G2.
FIG. 8 shows the data structure of each pack per unit time.
As shown in FIG. 8, since one pack of 2 pixels × 4 lines is transmitted in one clock, image data for one block can be transmitted in two clocks.

FIG. 9 shows an example of the transfer order of image data.
As shown in FIG. 9, the packs in the same block are continuously transmitted using the image data of each pixel in one pack as a pack stream.

[Receiver]
As illustrated in FIG. 1, the reception device G2 includes a reception unit 21, an image processing unit 22, and an image memory 23.

  The reception unit 21 receives the image data (pack stream) of each pack transmitted from the transmission device G1 via the network G3, and outputs it to the image processing unit 22.

The image processing unit 22 generates blocks by connecting the packs received by the receiving unit 21, and performs degeneration / decompression processing on the generated blocks. The image processing unit 22 sequentially writes each block after the compression / decompression processing to the image memory 23 to generate image data including each block after the image processing.
When generating a block, the image processing unit 22 generates a block by concatenating all packs in the same block transmitted continuously from the transmission device G1.

FIG. 10 shows the generation order of blocks after the degeneration / decompression processing.
As shown in FIG. 10, each block of 8 pixels × 8 lines is sequentially generated in the main scanning direction x, and when reaching the end of the main scanning direction x, the blocks are similarly generated by shifting 8 lines in the sub-scanning direction y. repeat.

  The image memory 23 is a memory that can hold at least one page of image data. For example, a DRAM (Dynamic Random Access Memory) or the like can be used as the image memory 23.

FIG. 11 shows a timing chart at the time of image data transfer. One square in FIG. 11 represents one line of image data, and the numbers in the square represent line numbers in the sub-scanning direction y.
As shown in FIG. 11, in the transmission apparatus G1, every time image data of 8 pixels × 8 lines is inputted, the image processing unit 12 performs a compression process to generate image data of each block of 4 pixels × 4 lines. To do. Each pack obtained by dividing the image data of 4 pixels × 4 lines as shown in FIG. 7 in the transmission device G1 is continuously transmitted.

  In the reception device G2, every time the image data of one block of packs transmitted continuously from the transmission device G1 is received, the image processing unit 22 connects the packs to generate the image data of the blocks, and degenerate / decompresses the data. Processing is performed to generate image data of each block of 8 pixels × 8 lines.

  As described above, the image data transfer system Ga according to the first embodiment performs image processing on image data in units of blocks, and the data amount of one pack is the target data amount for each block after the image processing. The transmission device G1 that divides the pack into one or a plurality of packs and transmits the divided packs via the network G3, and receives each pack transmitted from the transmission device G1 via the network G3. Are connected to each other to generate a block, image processing is performed on each generated block, and image data including each block after the image processing is generated. The transmitting device G1 continuously transmits all packs in the same block to the receiving device G2, and the receiving device G2 connects all the packs in the same block transmitted continuously from the transmitting device G1 to block Is generated.

  Since packs in the same block are transmitted continuously without time division, a memory such as a FIFO 15 that temporarily holds image data in both the transmission device G1 and the reception device G2 becomes unnecessary. It is possible to realize a compact device configuration and cost reduction. In addition, while maintaining the transferable data amount per unit time, it is possible to reduce the load at the time of transfer, particularly the load on the receiving device G2, and the image data can be transferred even with the receiving device G2 having low memory performance.

[Second Embodiment]
The burden on the receiving side can be reduced not only when transferring the above-described single-color image data but also when simultaneously transferring image data of a plurality of colors.

  FIG. 12 shows the main configuration of the image data transfer system Gb that can simultaneously transfer image data of a plurality of colors for each function. In FIG. 12, components having the same functions as those of the image data transfer system Ga are denoted by the same reference numerals.

  The image data transfer system Gb can simultaneously transfer image data of four colors of C (cyan), M (magenta), Y (yellow), and K (black) from the transmission device G1 to the reception device G2. As shown in FIG. 12, the image data transfer system Gb includes an input unit 11, an image processing unit 12 and a dividing unit 13 of the transmission device G1, and an image processing unit 22 of the reception device G2, which are necessary for transferring one color image data. The four transfer units 50 are provided as one transfer unit 50, and the image data of each color of C, M, Y, and K is simultaneously transferred by each transfer unit 50.

  Of the 40-bit data amount per unit time that can be transferred by the network G3, when the data amount allocated to the transfer of one-color image data is 8 bits, after the compression and compression process so that the data amount of one pack is 8 bits or less The image data of 4 pixels × 4 lines may be divided. For example, when divided in units of 1 pixel × 2 lines, 8 packs are obtained from one block. Therefore, each transfer unit 50 of the transmission device G1 continuously transmits 8 packs in the same block, and each of the reception devices G2 The transfer unit 50 may perform degeneration / decompression processing every time a block is generated by concatenating 8 packs received successively.

FIG. 13 shows an example of a pack divided in units of 1 pixel × 2 lines.
As shown in FIG. 13, the packs in the same divided block are continuously transmitted in the order of numbers (1) to (8). Since the amount of data for one color is 8 bits, a 32-bit area is used out of 40 bits that can be transferred by the network G3.
Since each pack in the same block is continuously transmitted, the received pack is temporarily held until a pack for one block is received, as in the case of transferring the monochrome image data. A memory becomes unnecessary, and the burden on the receiving device G2 is small.

As described above, the image data transfer system Gb according to the second embodiment includes the plurality of transfer units 50 that simultaneously transmit and receive image data of a plurality of colors, and similarly to the first embodiment, the transmission apparatus. G1 continuously transmits all packs in the same block to the receiving device G2, and the receiving device G2 generates a block by concatenating all packs in the same block transmitted continuously from the transmitting device G1. To do.
Therefore, even when image data of a plurality of colors is transferred at the same time, as in the first embodiment, the apparatus configuration can be made compact and the cost can be reduced. In addition, while maintaining the transferable data amount per unit time, it is possible to reduce the load at the time of transfer, particularly the load on the receiving device G2, and the image data can be transferred even with the receiving device G2 having low memory performance.

[Third Embodiment]
As shown in FIG. 12, in the image data transfer system Gb having a plurality of transfer units 50 capable of simultaneously transferring image data of a plurality of colors, when transferring monochrome image data, the transfer units 50 of other colors are used in combination. By doing so, the transfer rate of monochrome image data can be improved.

  FIG. 14 shows a configuration example of an image data transfer system Gc in the case where K color image data is transferred using the Y color and K color transfer units 50. This image data transfer system Gc can be configured by switching to the wiring connecting the FIFO 110 of each input unit 11 of Y color and K color in the image data transfer system Gb shown in FIG.

  In the transmission device G1, since image data of 8 lines can be simultaneously input to the image processing unit 12 of Y color and K color by the input unit 11 of Y color and K color, images of two different blocks in each image processing unit 12 Data can be generated simultaneously. The transmitter 14 transmits two different blocks of packs simultaneously. That is, the transmission unit 14 transmits all packs in one block divided by the Y color division unit 13 in parallel, and simultaneously transmits all packs in one block divided by the K color division unit 13. Send packs continuously.

  Since the transmission unit 14 transmits two packs per unit time, the Y color and K color division unit 13 makes the data amount for two packs equal to or less than the data amount per unit time that can be transferred by the network G3. Divide into one or more packs. For example, when the amount of data per unit time that can be transferred by the network G3 is 40 bits, the amount of data that can be transferred by the transfer unit 50 of one color is 20 bits or less. Dividing in units of pixels × 4 lines, the data amount of one pack can be 16 bits.

FIG. 15 shows a pack example of two blocks divided in units of 1 pixel × 4 lines.
As shown in FIG. 15, the Y color dividing unit 13 outputs the packs in the blocks of the 0th to 3rd lines successively in the order of numbers (1) to (4). In parallel with this output, the K color dividing unit 13 outputs the packs in the blocks of the 4th to 7th lines in the order of numbers (1) to (4).

FIG. 16 shows a data structure of a pack of two blocks transmitted simultaneously per unit time.
As shown in FIG. 16, since one pack of 1 pixel × 4 lines is transmitted in one clock from the Y color and K color transfer units 50, image data of two blocks can be transmitted in 4 clocks. .

  In the receiving device G2, the receiving unit 21 simultaneously receives two different block packs, and in parallel with the Y color image processing unit 22 connecting the packs of one block, the K color image processing unit 22 is connected. Concatenates each pack of another block to generate two blocks simultaneously.

FIG. 17 shows a timing chart at the time of image data transfer. One square in FIG. 17 represents one line, and the number in the square represents the line number in the sub-scanning direction y.
As shown in FIG. 17, the transmission device G1 performs degeneracy compression processing every time 8 pixels of image data of two blocks on the 0th to 15th lines are input in the main scanning direction x in the two transfer units 50. The packs obtained by dividing the image data of the two blocks on the 0th to 7th lines after the compression process are divided as shown in FIG.

  In the receiving device G2, the packs continuously transmitted from the transmitting device G1 are concatenated to generate two blocks of the 0th to 7th lines. Generate image data.

As described above, in the image data transfer system Gc according to the third embodiment, as in the first embodiment, the transmission device G1 continuously transmits all packs in the same block to the reception device G2. Then, the receiving device G2 generates a block by concatenating all packs in the same block transmitted continuously from the transmitting device G1.
The image data transfer system Gc includes a plurality of transfer units 50 that simultaneously transmit and receive a plurality of colors of image data. When transferring monochrome image data, two or more of the plurality of transfer units 50 are transferred. Transfer using unit 50.

  As a result, even when transferring monochrome image data in a configuration capable of simultaneously transferring image data of a plurality of colors, the burden on the receiving side can be reduced as in the first embodiment, and transfer of monochrome image data is possible. The rate can be increased.

[Contrast with comparative example]
If all packs in the same block are not transmitted continuously but are transmitted in a time division manner in units of lines, a memory such as a FIFO is required on both the transmission side and the reception side. The number of memory required depends on how the pack is divided.

FIG. 18A shows the transfer order of image data when the image data is expanded and divided in the sub-scanning direction y.
As shown in FIG. 18A, when 1 pixel × 2 lines arranged in the sub-scanning direction y are divided as one pack and transferred in units of lines, eight packs in each block are divided and transmitted in units of 2 lines. Specifically, the packs (1-1), (1-2), (1-3), and (1-4) in the blocks of the 0th to 3rd pixels in the main scanning direction x are consecutively arranged in this order. Then, the packs (1-1), (1-2), (1-3), and (1-4) in the block next to the 4th to 7th pixels are sequentially transmitted in this order. . When the packs (1-1), (1-2), (1-3), and (1-4) of each block are transmitted to the end in the main scanning direction x, the 0th to 3rd pixels in the main scanning direction x are transmitted. Returning to the block, the packs of numbers (2-1), (2-2), (2-3), and (2-4) in each block are continuously transmitted.
In this way, since the image data generated simultaneously in units of blocks is time-divisionally transmitted to the 0th and 1st lines and the 2nd and 3rd lines, while the 0th and 1st line image data is being transferred, 2 And one FIFO 15 that temporarily holds the image data of the third line is required.

FIG. 18B shows the transfer order of image data when the image data is expanded and divided in the main scanning direction x.
As shown in FIG. 18B, when 4 pixels × 1 lines arranged in the main scanning direction x are divided as one pack and transferred in units of lines, four packs in each block are divided and transmitted in units of one line. Specifically, after transmitting 1 pack of the (1) -th block of the 0th to 3rd pixel blocks in the main scanning direction x, 1 pack of the (1) th block of the 4th to 7th pixel blocks in the main scanning direction x. Send. When the (1) pack of each block is transmitted up to the end in the main scanning direction x, the block returns to the 0th to 3rd pixel block in the main scanning direction x, and the (2) pack of each block is transmitted continuously. . Similarly, the (3) and (4) packs are transmitted.
In this case, since the image data generated simultaneously in units of blocks is time-divisionally transmitted for each of the 0th to 3rd lines, the image data of each line is transferred while transferring the image data of the previous line. Three FIFOs 15 that temporarily hold image data are required.

[Comparative Example 1]
FIG. 19 shows a configuration example of an image data transfer system Ta that can transfer image data of a plurality of colors. In FIG. 19, components having the same functions as those of the image data transfer system Gb are denoted by the same reference numerals.
In the image data transfer system Ta, one block of 4 pixels × 4 lines after the compression process is expanded in the sub-scan direction and divided in units of 1 pixel × 2 lines as shown in FIG. Divide and transfer. Therefore, in the image data transfer system Ta, as shown in FIG. 19, one FIFO 15 is arranged for each color in each of the transmission device G1 and the reception device G2.

FIG. 20 shows the transmission order of image data of each color in the image data transfer system Ta.
As shown in FIG. 20, in the transfer unit 50 of each color, the packs (1-1), (1-2), (1-3), and (1-4) of each block are sequentially transmitted in this order. After that, the packs of numbers (2-1), (2-2), (2-3), and (2-4) of each block delayed by the FIFO 15 are continuously transmitted.

FIG. 21 shows the transfer order of image data after the compression process.
As shown in FIG. 21, the packs of each block are transferred in units of lines in the order in which they are arranged in the main scanning direction x.

FIG. 22 shows a timing chart at the time of image data transfer. One square in FIG. 22 represents one line, and the number in the square represents the line number in the sub-scanning direction y.
As shown in FIG. 22, since the packs of the blocks arranged in the main scanning direction x are transmitted in a time-sharing manner in units of two lines, there are four lines such as the 0th to 3rd lines, the 4th to 7th lines, etc. The degeneration / decompression processing is performed at the time when the image data of the minute is received.

[Comparative Example 2]
FIG. 23 shows an example of the configuration of an image data transfer system Tb that includes a plurality of transfer units capable of simultaneously transferring image data of a plurality of colors and transfers image data of a single color using another color transfer unit in combination. Yes. This image data transfer system Tb can be configured by switching to the wiring connecting the FIFO 110 of each input unit 11 of Y color and K color in the image data transfer system Ta shown in FIG. In FIG. 23, components having the same functions as those of the image data transfer system Ta are denoted by the same reference numerals.

FIG. 24 shows the transmission order of monochrome image data in the image data transfer system Ta.
As shown in FIG. 24, in the Y-color transfer unit 50, (1-1), (1-2), (1-3), (1-3) ( After the 1-4th pack is continuously transmitted in this order, the numbers (2-1), (2-2), (2-3), and (2-4) of each block delayed by the FIFO 15 are transmitted. The packs are sent sequentially in this order. Similarly, in the K-color transfer unit 50, the numbers (1-1), (1-2), (1-3), and (1-4) of the blocks located on the 4th to 7th lines in the sub-scanning direction y are also shown. The packs (2-1), (2-2), (2-3), and (2-4) of each block delayed by the FIFO 15 are sequentially transmitted in this order. Send continuously. Since the transfer unit 50 for each color transfers one pack of 8 bits per unit time, it is possible to transmit monochrome image data using a 16-bit area out of 40 bits that can be transferred by the network G3 per unit time. .

FIG. 25 shows a timing chart at the time of image data transfer. One square in FIG. 25 represents one line, and the number in the square represents the line number in the sub-scanning direction y.
As shown in FIG. 25, since the image data of two blocks are transmitted at the same time, the degeneration / decompression processing is performed at the time when the image data for 8 lines such as the 0th to 7th lines, the 8th to 15th lines, etc. is received. Has been done.

[Comparative Example 3]
FIG. 26 shows a configuration example of an image data transfer system Tc in the case where a plurality of transfer units capable of simultaneously transferring image data of a plurality of colors are provided, and monochrome image data is combined with other color transfer units. . In FIG. 26, components having the same functions as those of the image data transfer system Gb are denoted by the same reference numerals. The image data transfer system Tc can use four color transfer units 50 of Y, M, C, and K. Among them, image data can be input simultaneously to the image processing units 22 of Y color and K color. The FIFO 111 of each input unit 11 is connected.

  In the image data transfer system Tc, one block of 4 pixels × 4 lines after the compression process is expanded in the main scanning direction x as shown in FIG. 18B and divided in units of 4 pixels × 1 line. Transfer in time division. Therefore, in the image data transfer system Tc, as shown in FIG. 26, three FIFOs 15 are arranged for each color in each of the transmission device G1 and the reception device G2.

FIG. 27 shows the transfer order of monochrome image data in the image data transfer system Tc.
As shown in FIG. 27, in the image data transfer system Tc, each block is divided into odd-numbered (EVEN) blocks whose arrangement order in the main scanning direction x is 1, 3, 5,. .. and even numbered (ODD) blocks. In the Y-color transfer unit 50, the (1) number packs of each block of the EVEN are sequentially transmitted in sequence, and then the (2) number packs of the respective blocks are sequentially transmitted. Similarly, after the (3) th pack of each block of EVEN is transmitted, the (4) th pack is transmitted. In the K-color transfer unit 50, the packs (1) to (4) in each block of the ODD are arranged in units of one line in the same manner as the Y-color transfer unit 50 except that EVEN replaces the ODD block. Send in time division.

FIG. 28 shows a timing chart at the time of image data transfer. One square in FIG. 28 represents one line, and the number in the square represents the line number in the sub-scanning direction y.
As shown in FIG. 28, since the image data of two blocks are simultaneously transmitted in units of one line, the time point when image data for four lines is received such as the 0th to 3rd lines, the 4th to 7th lines, etc. Degeneration / decompression processing is performed at.

As shown in FIGS. 17, 25, and 28, the comparative example 1 extended in the sub-scanning direction y requires less FIFO 15 than the comparative example 2 extended in the main scanning direction x, but the transfer rate is high. Low. Although the comparative example 2 has a high transfer rate, a large number of FIFOs 15 are required.
On the other hand, according to the present embodiment, since the FIFO 15 is unnecessary and there is no burden on the receiving device G2, image data can be transferred regardless of the performance of the receiving device G2. Further, it is possible to obtain a higher transfer rate than that of the first comparative example while maintaining the data amount transferred per unit time at the target data amount.

The above embodiment is a preferred example of the present invention, and the present invention is not limited to this. Modifications can be made as appropriate without departing from the spirit of the present invention.
For example, in the above-described embodiment, an example in which two-color transfer units 50 are used together to transfer single-color image data has been described. However, the network G3 can transfer the data amount of each pack that is simultaneously transferred by each transfer unit 50. If the amount of data per unit time is less than or equal to, it is possible to simultaneously transfer three or more different blocks using transfer units 50 of three or more colors in combination.

  In addition, as long as all packs in the same block are transmitted continuously, the pack dividing method is not limited to the above-described example.

Ga, Gb, Gc Image data transfer system G1 Transmitter 11 Input unit 110 FIFO
12 image processing unit 13 dividing unit 14 transmitting unit G2 transmitting device 21 receiving unit 22 image processing unit 23 image memory 50 transfer unit G3 network Ta, Tb, Tc image data transfer system (comparative example)
15 FIFO

Claims (12)

Image data is processed in block units, and each block after the image processing is divided into one or a plurality of packs so that the data amount of one pack becomes the target data amount, and each divided pack is transmitted via a network. A transmitting device for transmitting
Each pack transmitted from the transmission device via the network is received, and the received packs are connected to generate a block, each generated block is subjected to image processing, and each block after the image processing is processed. A receiving device for generating image data,
The transmitting device continuously transmits all packs in the same block to the receiving device,
The image data transfer system, wherein the reception device generates the block by concatenating all packs in the same block continuously transmitted from the transmission device.   The image data transfer system according to claim 1, wherein the transmission device generates a block having a target data amount by performing image processing that is completed for each block.   3. The image data according to claim 1, wherein the transmission device simultaneously generates a plurality of different blocks after image processing by performing independent image processing for each of the blocks. 4. Transfer system. The transmitting device simultaneously transmits the packs of the different blocks;
The image data transfer system according to any one of claims 1 to 3, wherein the receiving device receives the pack of the plurality of different blocks at the same time.   5. The image data according to claim 1, wherein the reception device generates a block having a target data amount by performing image processing that is completed for each block at one time. Transfer system.   The image data transfer system according to any one of claims 1 to 5, wherein the receiving device generates a plurality of different blocks simultaneously by performing independent image processing for each of the blocks. The transmission device performs compression processing as the image processing, and the amount of data transferred per unit time for each block after the compression processing is equal to or less than the amount of data per unit time that can be transferred by the network. Dividing into one or more packs,
7. The image data transfer system according to claim 1, wherein the receiving device performs decompression processing as the image processing, and generates a block having an original data amount before the compression processing. .   The image data transfer system according to claim 7, wherein the compression process is a BTC compression process or a degeneracy compression process.   A plurality of transfer units that transfer image data of a plurality of colors at the same time are provided, and when transferring single-color image data, two or more transfer units among the plurality of transfer units are used for transfer. The image data transfer system according to claim 1.   The image data transfer system according to claim 1, wherein the network is a network that serially transfers the image data.   The image data transfer system according to claim 1, wherein the network standard is V-by-One (registered trademark). In the transmission device,
Image processing the image data in units of blocks;
Dividing each block after the image processing into one or a plurality of packs so that one pack has a constant data amount;
Transmitting each of the divided packs via a network;
In the receiving device,
Receiving each pack transmitted from the transmitting device via the network;
Concatenating each received pack to generate a block, and image processing each generated block;
Generating image data consisting of each block after the image processing,
In the transmitting step, all packs in the same block are continuously transmitted to the receiving device,
In the receiving step, the block is generated by concatenating all packs in the same block continuously transmitted from the transmitting device.

Images