JP2005277687A - Method and apparatus for image processing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image processing method and an image processing apparatus capable of efficiently executing rotating processing of image data without increasing processing load on a computer more than necessary by executing the same rotating processing for both monochromatic image data and color image data even in a small and low-cost configuration compared to a conventional apparatus. <P>SOLUTION: In the image processing method for the monochromatic or color image data two-dimensionally developed in a memory, the image data are read using the same number of pixels as one unit in a row direction and a column direction to execute transposition processing, and the data after the transposition processing are written into an original address of the memory. In this method, it is determined whether the image data are monochromatic image data or color image data, and if the image data are determined to be monochromatic image data, a memory region specified by the reading address or writing address of the image data is segmented into a plurality of regions at the time of transposition processing, and one of the segmented memory regions is selected and read or written. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image processing method and an image processing apparatus for rotating image data stored in a page memory.

  In an image processing apparatus that processes image data, such as a facsimile machine, a digital copying machine, a printer, or a multifunction machine that integrates these functions, image data read by the image processing apparatus or an image input from an external device Some have a function of rotating data 90 degrees clockwise or counterclockwise and recording the data on a sheet (for example, see Patent Document 1). Using such image data rotation processing, the long and short directions of the graphic drawn by the image data are made to coincide with the long and short directions of the paper to be printed out, and the paper to be printed out set in a predetermined direction is out of paper. Even in such a case, it is possible to continue the print output process using the other paper set with the paper changed 90 degrees.

  The rotation processing of image data in the conventional image processing is performed as follows using a page memory. In other words, image data read by the image processing device or image data input from an external device is temporarily stored in a buffer, and when a predetermined page of image data is stored in the buffer, later reading is considered. The image data for one page stored in the buffer is developed at a predetermined address of the page memory calculated in this way, and the developed image data is read out and sent to the recording unit.

As image data, not only monochrome image data but also color image data is handled. Since the capacity of the color image data is larger than the capacity of the monochrome image data, if the image data is color image data so as to reduce the memory capacity for processing the image data, the image data is divided into a plurality of blocks, An image forming apparatus is disclosed that reduces the memory capacity to be used by performing data compression and decompression processing for each divided block (see, for example, Patent Document 2).
JP 2000-268169 A JP 2002-232692 A

  However, in a conventional image processing apparatus that performs rotation processing of image data, an arithmetic device for calculating the address of the page memory to which the image data is to be written is necessary, for example, by multiplication processing. There is a problem that high cost is inevitable. In addition, in the method of performing data compression and decompression processing for each divided block in order to reduce the memory capacity, the computer processing load increases due to the data compression and decompression processing, which increases the bulk and cost of the device configuration. This is one of the causes.

  Furthermore, when the units of the divided blocks are different between a monochrome image and a color image, the address control for performing data compression and decompression processing becomes complicated, and the computer processing load for performing rotation processing increases. There was also a point.

  The present invention has been made in view of such circumstances. Even if the configuration is smaller and lower in cost than the conventional apparatus, the computer processing is performed by performing the same rotation processing on the black and white image data and the color image data. An object of the present invention is to provide an image processing method and an image processing apparatus capable of efficiently rotating image data without increasing the load more than necessary.

  To achieve the above object, the image processing method according to the first aspect of the present invention reads out the same number of pixels in the row direction and the column direction as a unit from the monochrome or color image data expanded two-dimensionally in the memory. In the image processing method of executing transposition processing and writing the data after transposition processing to the original address of the memory, it is determined whether the image data is monochrome image data or color image data, and the image data is a monochrome image If the data is determined to be data, the memory area specified by the read address or the write address of the image data is divided into a plurality of parts at the time of the transposition process, and the selected one memory area is read or written. Features.

  In the image processing method according to the first aspect of the present invention, the same number of pixels in the row direction and the column direction, that is, a plurality of squares of n × n (n is a natural number), for one page of image data expanded two-dimensionally in the memory. An operation of reading a pixel as a unit, performing a transposition process in which the row direction and the column direction are switched, and writing the data after the transposition process in the original address area of n × n of the memory is performed on image data for one page. Sequentially for this. When the image data is color image data, for example, when a color is specified by RGB, it is stored as one pixel in a page memory area of 3 m bits by m bits for one read address or write address. In the case of monochrome image data, m bits are stored as one pixel for one read address or write address. For reading or writing monochrome image data, the same read address or write address as color image data is used, and a memory area specified by the same address is an area indicated by upper m bits, an area indicated by middle m bits, And the three areas indicated by the lower m bits. Then, for example, by reading or writing using the area indicated by the upper m bits, the monochrome image data is read or written pixel by pixel. This eliminates the need for an arithmetic unit (divider) for calculating the write address in the page memory, and it is only necessary to add a selection circuit for the three divided areas, thereby reducing the size and cost of the device configuration. Can be achieved. Further, even when the image data is black and white image data, the rotation process can be performed using the same read address or write address as in the case of color image data, without complicated address control. Image data can be rotated.

  In the image processing method according to the second invention, in the first invention, when the image data is monochrome image data, a memory area is used with one pixel as m (m is a natural number) bits, and the image data is color image data. If the image data is determined to be black and white image data when one pixel is 3 m bits and the image data is determined to be monochrome image data, the divided 3 specified by the image data read address or write address is used. One of the memory areas is selected and read or written.

  In the image processing method of the second invention, for reading or writing of the monochrome image data, the same read address or write address as the color image data is used, and a memory area specified by the same address is an area indicated by upper m bits, The area is divided into three areas indicated by middle m bits and areas indicated by lower m bits. Then, for example, an area indicated by upper m bits is selected, and monochrome image data is read or written. As a result, an arithmetic device (divider) for calculating the write address in the page memory is not required, and the size and cost of the device can be reduced. Further, even when the image data is black and white image data, the rotation process can be performed using the same read address or write address as in the case of color image data, without complicated address control. Image data can be rotated.

  According to a third aspect of the present invention, there is provided a memory for expanding and storing the image data in two dimensions, and partial image data having the same number of pixels in the row direction and the column direction in the image data stored in the memory. In the image processing apparatus comprising: means for reading out the image data and executing transposition processing; and means for reading out image data for one page after the transposition processing from the memory; means for determining the type of the image data; Means for dividing the memory area specified by the read address or the write address of the image data into a plurality of memory areas when the image data is determined to be transposed, and selecting or reading one of the divided memory areas It is characterized by providing.

  In the image processing apparatus according to the third aspect of the present invention, the same number of pixels in the row direction and the column direction, that is, a plurality of squares of n × n (n is a natural number), for one page of image data expanded two-dimensionally in the memory An operation of reading a pixel as a unit, performing a transposition process in which the row direction and the column direction are switched, and writing the data after the transposition process in the original address area of n × n of the memory is performed on image data for one page. Sequentially for this. When the image data is color image data, for example, when a color is specified by RGB, it is stored as one pixel in a page memory area of 3 m bits by m bits for one read address or write address. In the case of monochrome image data, m bits are stored as one pixel for one read address or write address. For reading or writing monochrome image data, the same read address or write address as color image data is used, and a memory area specified by the same address is an area indicated by upper m bits, an area indicated by middle m bits, And the three areas indicated by the lower m bits. Then, for example, by reading or writing using the area indicated by the upper m bits, the monochrome image data is read or written pixel by pixel. This eliminates the need for an arithmetic unit (divider) for calculating the write address in the page memory, and it is only necessary to add a selection circuit for the three divided areas, thereby reducing the size and cost of the device configuration. Can be achieved. Further, even when the image data is black and white image data, the rotation process can be performed using the same read address or write address as in the case of color image data, without complicated address control. Image data can be rotated.

  According to the present invention, it is possible to generate image data rotated by one side of the page memory without requiring a circuit for performing complicated address calculation. Therefore, a circuit having a small circuit scale and a necessary capacity is provided. Thus, the rotation processing of the image data can be performed. Further, even when the image data is black and white image data, the rotation process can be performed using the same read address or write address as in the case of color image data, without complicated address control. Image data can be rotated. As a result, it is possible to realize an image processing apparatus that can perform image data rotation processing with high memory use efficiency even with a small-scale configuration.

  Hereinafter, the present invention will be described in detail with reference to the drawings showing embodiments thereof. FIG. 1 is a block diagram showing a configuration of a facsimile composite apparatus 20 as an image processing apparatus of the present invention.

  The facsimile multifunction device 20 includes a control unit 1, a reading unit 2, a recording unit 3, a display unit 4, an operation unit 5, a ROM 6, a RAM 7, a codec unit 8, an image memory 9, a page memory 10, a buffer 11, a modem 12, an NCU ( Network Control Unit) 13, a PC interface unit 14 and the like. The facsimile multifunction device 20 responds to a reading function for reading an original by the reading unit 2 to acquire image data, read image data, image data received by facsimile communication, or image data received from an externally connected PC. A recording function for recording an image in the recording unit 3 and a transmission function for facsimile transmission of read image data or received image data are provided.

  Specifically, the control unit 1 is configured by a CPU, and is connected to the above-described hardware units of the facsimile multifunction peripheral 20 via the bus 15. The control unit 1 controls the above-described hardware units and also controls the ROM 6. Various software functions are executed in accordance with the control program stored in. The reading unit 2 reads a document using a CCD image sensor, for example, and outputs the read image data. Specifically, the optical unit irradiates and scans the document fed to the platen glass, and the reflected light from the document is captured into a CCD image sensor via a mirror, a lens, etc., and the scanned document image data is captured. Read. The read image data is output after, for example, shading processing.

  The recording unit 3 is an electrophotographic printer device, and displays images corresponding to image data of a document read by the reading unit 2, image data received by facsimile communication, image data sent from an external PC, and the like. Print on paper. The display unit 4 is a display device such as a liquid crystal display device or a CRT display. The display unit 4 displays an operation state of the facsimile multifunction device 20, displays a screen for prompting an operation input to the user, or reads an image of a document read for transmission. Data, image data transmitted from other facsimile machines and PCs, etc. are displayed.

  The operation unit 5 includes character keys, numeric keys, abbreviated dial keys, one-touch dial keys, various function keys, and the like necessary for operating the facsimile multifunction device 20. The operation unit 5 includes a rotation processing setting key 5a for setting whether or not to perform image data rotation processing using the page memory 10 and the buffer 11 as function keys. In addition, the display part 4 can substitute for a part or all of the various keys of the operation part 5 by making the display part 4 into a touch panel system. The ROM 6 stores in advance various software programs necessary for the operation of the facsimile composite apparatus 20. The RAM 7 is composed of SRAM, flash memory, etc., and stores temporary data generated when software is executed. The codec unit 8 encodes and compresses the image data and decodes the encoded and compressed image data. The image memory 9 stores image data obtained by reading and encoding a document.

  The page memory 10 is composed of SDRAM, and stores one page of image data read by the reading unit 2 and one page of image data received from another facsimile apparatus or PC. The image data for one page accumulated and developed in the page memory 10 is read to the recording unit 3, and an image corresponding to the read image data is recorded. The buffer 11 has 24 flip-flops for every 16 pixels configured in a 4 × 4 matrix, and multi-value data including 8 flip-flops as a set is converted into R, G, and B data. Hold as value. Data can be written or read between the page memory 10 and the buffer 11 with 4 × 4 16-pixel data of the page memory 10 as a unit, and the above-described data writing can be performed as necessary. Alternatively, transposed image data in the image data rotation process is generated by performing read control.

  The modem 12 is connected to the bus 15 and is a facsimile modem capable of facsimile communication. The modem 12 is also connected to the NCU 13 connected to the bus 15. The NCU 13 is hardware that performs operations of closing and opening the line L1 with a public switched telephone network (PSTN), and connects the modem 12 to the PSTN as necessary. The facsimile composite apparatus 20 is connected to other facsimile apparatuses by PSTN so that normal facsimile communication can be performed. The PC interface unit 14 is connected to an external PC via, for example, a LAN communication line L2, and transmits / receives data to / from the PC. Various image data created and edited by an external PC are transmitted to the facsimile multifunction apparatus 20 (PC interface unit 14) via the communication line L2, and an image corresponding to the transmitted image data is transmitted to the facsimile multifunction apparatus 20. The data is printed out on a sheet at (recording unit 3).

  The operation of the recording process in the facsimile multifunction apparatus 20 having the above-described configuration will be described below. FIG. 2 is a flowchart showing an operation procedure of recording processing in the image processing apparatus according to the embodiment of the present invention, FIG. 4 is a diagram showing an accumulation state of image data in the page memory 10, and FIGS. FIG. 10 is a diagram for explaining a 90-degree rotation process in the clockwise direction of image data.

  As shown in FIG. 2, one page of image data read by the reading unit 2 or image data received from another facsimile machine or PC is stored in the page memory 10 (step S1). FIG. 3 is a flowchart of the process of the control unit 1 in step S1. As shown in FIG. 3, the control unit 1 determines whether the image data read by the reading unit 2 or the image data received from another facsimile apparatus or PC is monochrome image data or color image data. Is discriminated (step S11). When it is determined that the image is a color image (step S11: YES), as shown in FIG. 4A, 8 bits for each of RGB, and a total of 24 bits for one pixel of data for one read address or write address Are stored in the page memory 10 in association with (step S12). If it is determined that the image is a black and white image (step S11: NO), as shown in FIG. 4B, data for one pixel is stored in the page memory 10 with 8 bits (step S13).

  As shown in FIG. 4B, a 24-bit memory area is associated with one read address or write address. However, in this embodiment, the memory area is represented by the upper 8 bits, the middle 8 An area indicated by bits and an area indicated by lower 8 bits are divided into three areas, and which area is used is selected using a selection circuit.

  FIG. 5 is a diagram illustrating a configuration example of a selection circuit that selects a use area of the page memory 10 (SDRAM). In FIG. 5, SDRAM (R), SDRAM (G), and SDRAM (B) are respectively an area indicated by the upper 8 bits, an area indicated by the middle 8 bits, and an area indicated by the lower 8 bits of the page memory 10. In the figure, it is selected which 8-bit data is to be read or written out of the 24-bit data Data (23-0).

  Next, the control unit 1 determines whether or not the rotation process is set based on whether or not the rotation process setting key 5a is pressed (step S2). When rotation processing is not set (step S2: NO), image data is read from the page memory 10 to the recording unit 3 in the same order as written in the page memory 10 (step S8), and corresponds to the read image data. The image to be printed is printed out on a sheet by the recording unit 3 (step S9).

  When rotation processing of image data is set (step S2: YES), 16 pixels of 4 × 4 square shape in the image data stored in the page memory 10 are set as one unit (block), and Data of one block is read from the page memory 10 and written to the buffer 11 (step S3). In the writing process to the buffer 11, data is written in the row direction of the buffer 11. After the write processing to the buffer 11 is completed, the data written to the buffer 11 is read from the column direction, and the read data is written to the original 4 × 4 memory area of the page memory 10 (step S4). Thereby, transposed image data is generated as intermediate data for the rotation process. The control unit 1 determines whether or not transposed image data generation with 4 × 4 pixels as a unit over one page stored in the page memory 10 is completed (step S5). (Step S5: NO), the operation returns to Step S3 to generate transposed image data in the next block. When transposition image data generation is completed over one page (step S5: YES), the operation proceeds to step S6.

  FIG. 6 is a diagram showing a first data accumulation state in the page memory 10. As shown in FIG. 6, the image data for one page is divided into a total of 6 blocks, 3 in the row direction and 2 in the column direction. FIG. 7 is a diagram showing transposed image data obtained by reading or writing data with the buffer 11. The hatched portions in FIGS. 6 and 7 indicate where the data read before transposition is written after transposition.

  Next, the read address is controlled, the transposed image data is read from the page memory 10 to the recording unit 3 (step S6), and the rotated image corresponding to the read transposed image data is printed out on a sheet by the recording unit 3 (step S6). S7). Reading of each line from the page memory 10 is performed in the order described in the leftmost column of FIG. 6, and one line is read alternately in two blocks. By controlling the read address, an image rotated 90 degrees clockwise as shown in FIG. 8 is obtained.

  When the image data is monochrome image data, the data read or write control method differs from the buffer 11 for generating transposed image data. FIG. 9 is a diagram illustrating a first data accumulation state in the page memory 10 when the image data is monochrome image data. As in the case of color image data, the image data for one page is divided into a total of 6 blocks, 3 in the row direction and 2 in the column direction. A 24-bit data read or write area is provided for one address. For data reading, the first line is the upper 8 bits of the first line of the block, the second line is the upper 8 bits of the second line of the same block, and the third line is the upper 8 bits of the third line of the same block. Only the upper 8 bits are sequentially read out and written to the page memory 10 as shown in FIG. That is, data is read or written by accessing a different address every 8 bits. FIG. 10 is a diagram showing transposed image data obtained by reading or writing data with the buffer 11. Thus, by performing address control so as to access every 8 bits, even if the image data is monochrome image data, it is possible to generate transposed image data in the same manner as color image data.

  Next, the read address is controlled, the transposed image data is read from the page memory 10 to the recording unit 3 (step S6), and the rotated image corresponding to the read transposed image data is printed out on a sheet by the recording unit 3 (step S6). S7). The reading of each line from the page memory 10 is performed in the order described at the left end of FIG. 7, and one line is read alternately by two blocks. By controlling the read address, an image rotated 90 degrees clockwise as shown in FIG. 8 is obtained. Even when the image data is monochrome image data, the reading of each line from the page memory 10 is performed in the order described at the left end of FIG. 10, and is read by 8 bits alternately in two blocks. By controlling the read address, an image rotated 90 degrees clockwise as shown in FIG. 8 is obtained.

  In the above-described embodiment, the case where the transposed image data is generated with 4 × 4 pixels as one unit is described. However, the present invention is not particularly limited to 4 × 4 pixels, and for example, 8 × 8 pixels are used. The value of n may be arbitrary as long as the unit is a square pixel block.

  In this embodiment, the facsimile complex apparatus is described as an example. However, it goes without saying that the present invention can be applied to all apparatuses that rotate and output acquired image data, such as a facsimile apparatus, a digital copying machine, and a printer. Yes.

1 is a block diagram illustrating a configuration of an image processing apparatus (facsimile multifunction apparatus) according to the present invention. 5 is a flowchart showing an operation procedure of recording processing in the image processing apparatus according to the embodiment of the present invention. It is a flowchart which shows the operation | movement procedure of the page memory accumulation | storage process of the image processing apparatus which concerns on embodiment of this invention. It is a figure which shows the accumulation | storage state in the page memory of image data. It is a figure which shows the structural example of the selection circuit which selects the use area | region of a page memory (SDRAM). It is a figure for demonstrating the 90 degree rotation process to the clockwise direction of image data. It is a figure for demonstrating the 90 degree rotation process to the clockwise direction of image data. It is a figure for demonstrating the 90 degree rotation process to the clockwise direction of image data. It is a figure which shows the first data accumulation state in a page memory in case image data is monochrome image data. It is a figure which shows the transposition image data obtained by the data reading or writing between buffers.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control part 2 Reading part 3 Recording part 5 Operation part 5a Rotation process setting key 6 ROM
7 RAM
10 page memory 11 buffer

Claims (3)

  For black and white or color image data expanded two-dimensionally in the memory, the same number of pixels are read out as one unit in the row direction and the column direction, and transposition processing is executed. In the image processing method for writing to an address, it is determined whether the image data is monochrome image data or color image data, and if it is determined that the image data is monochrome image data, the image data is read out during transposition processing. An image processing method, wherein a memory area specified by an address or a write address is divided into a plurality of areas, and the divided memory area is selected and read or written.   When the image data is monochrome image data, a memory area is used with 1 pixel as m (m is a natural number) bits, and when the image data is color image data, a memory area is used with 1 pixel as 3 m bits. When it is determined that the image data is monochrome image data, one of the three divided areas specified by the read address or the write address of the image data is selected and read or written during the transposition process. The image processing method according to claim 1, further comprising:   A memory for expanding and storing the image data in two dimensions, and means for executing transposition processing by reading out partial image data of the same number of pixels in the row direction and the column direction in the image data stored in the memory; , In an image processing apparatus comprising means for reading out image data for one page after transposition processing from the memory, when the means determines the type of the image data, and the means determines that the image data is monochrome image data, Image processing comprising: a memory area specified by a read address or a write address of image data at the time of transposition processing, and a means for selecting and reading or writing one divided memory area apparatus.

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