JP2004007403A - Image forming device, memory control device and memory control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a memory control device, a memory control method and an image forming device capable of improving the application efficiency of page memories. <P>SOLUTION: The image forming device for controlling the storage of image data by using a memory area in which a plurality of page memories having regular size are continuously arranged comprises a number-of-page memories calculation means for calculating the number of page memories necessary for storing the image data, a grouping means for grouping the page memories in each continued page memories corresponding to the number of page memories calculated by the calculation means and a page memory acquiring means for acquiring the page memories in each page memory group grouped by the grouping means. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a memory control device and a memory control method for a page memory having a function of storing input image data and printing out the stored image data, and an image forming apparatus.
[0002]
[Prior art]
This is an image forming apparatus capable of forming an image in color. Even if image data for four colors of Y (Yellow), M (Magenta), C (Cyan), and K (black K) cannot be stored in the memory, There is an image processing apparatus that aims to enable image formation without increasing the memory capacity (for example, see Patent Document 1).
[0003]
In this image forming apparatus, Y, M, C, and K image forming units are provided in tandem along an intermediate transfer belt. Further, the image forming apparatus includes a resolution conversion unit that converts the resolution of the image data, and a determination unit that determines whether the memory overflows. When it is determined that the memory overflows, the image data whose resolution has been reduced by the resolution conversion means is compressed, stored in the memory, and used for forming a color image.
[0004]
Conventionally, input / output of image data has been performed between an input / output and an HDD serving as a secondary storage device via an intermediate buffer. This buffer is, for example, a page memory, and is used to compensate for the low transfer speed of the HDD.
[0005]
The input image data is temporarily stored in a page memory having a fast access speed, and is transferred to a secondary storage device such as an HDD. At the time of output for printing, the image data transferred from the HDD to the page memory is output.
[0006]
When this page memory is used, a plurality of page memories may be used by one image data. For example, if one page of the page memory has a capacity capable of storing A4 size image data, two page memories are required to store A3 size image data.
[0007]
At this time, when the image data is stored using two continuous page memories, the management of the page memories becomes easier and the processing speed is improved. Here, “continuous” is an address on two page memories, and two pages of two pages are located between the minimum address and the maximum address so that there is no page memory that does not belong to the two page memories. It means that the page memory is arranged on the memory.
[0008]
Unless the page memory is continuously acquired and the image data is not stored, it is necessary to generate and hold management information for associating discontinuous page memories. Therefore, a memory for holding the management information is newly required. Further, processing for generating and holding management information is newly added.
[0009]
Also, if the page memories are discontinuous, address calculations required for editing image data, such as date data, page data, partition lines, stamp synthesis, and shading, are complicated.
[0010]
[Patent Document 1]
JP 2000-253223 A
[0011]
[Problems to be solved by the invention]
For the above reasons, if multiple page memories are required, it is better to acquire continuous page memory and store the image data. Occurs because the page memory does not exist.
[0012]
An object of the present invention is to provide a memory control device, a memory control method, and an image forming apparatus capable of improving the use efficiency of a page memory in view of such a problem.
[0013]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides an image forming apparatus which performs control for storing image data by using a memory area in which a plurality of page memories having a prescribed size are continuously arranged. Grouping the page memories into page memory number calculating means for calculating the number of page memories required for storing image data, and the page memories for each continuous page memory of the number of page memories calculated by the page memory number calculating means. And a page memory obtaining unit that obtains the page memory for each group of the page memories grouped by the grouping unit.
[0014]
In order to solve the above problem, the present invention is characterized in that the number of groups of page memories to be grouped by the grouping means is the largest among the number of groups that can be grouped. I do.
[0015]
According to another aspect of the present invention, the page memory is used for storing image data input to the image forming apparatus and image data output to an image forming unit that forms an image. It is characterized by the following.
[0016]
In order to solve the above problem, the present invention is characterized in that the page memory number calculating means calculates the page memory number based on the number of color components of the image data.
[0017]
According to another aspect of the present invention, the page memory number calculation unit calculates the number of page memories based on the number of color components required to form the image data on a recording medium. It is characterized by doing.
[0018]
In order to solve the above problem, the present invention is characterized in that the page memory number calculation means calculates the page memory number based on the size of the image data.
[0019]
In order to solve the above-mentioned problem, the present invention is characterized by further comprising a storage unit for storing the input image data via the page memory.
[0020]
According to another aspect of the present invention, there is provided a memory control device that performs control for storing image data using a memory area in which a plurality of page memories having a specified size are continuously arranged. A page memory number calculating means for calculating the number of page memories required to store the image data, and the page memory for each continuous page memory of the number of page memories calculated by the page memory number calculating means. It is characterized by having a grouping means for grouping, and a page memory obtaining means for obtaining the page memory in a group of page memories grouped by the grouping means.
[0021]
According to another aspect of the present invention, there is provided a memory control method for performing control for storing image data using a memory area in which a plurality of page memories having a prescribed size are continuously arranged. A step of calculating the number of page memories required to store the image data, and a step of calculating the number of page memories required by the step of calculating the number of page memories. The method includes a grouping step of grouping memories, and a page memory obtaining step of obtaining the page memories in groups of the page memories grouped by the grouping unit.
[0022]
As described above, according to the present invention, it is possible to provide a memory control device, a memory control method, and an image forming apparatus capable of improving the use efficiency of a page memory.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0024]
The structure of the image forming apparatus according to one embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a configuration diagram of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a configuration diagram of the image forming unit. FIG. 3 is a block diagram showing a configuration of a control unit corresponding to the memory control device. FIG. 4 is a developed view showing images on two surfaces formed on the intermediate transfer belt. FIG. 5 is a block diagram showing the internal configuration of the image processing unit. FIG. 6 is a block diagram showing the internal configuration of the memory controller and the image memory.
[0025]
As shown in FIG. 1, the image forming apparatus includes a scanner unit 1, a printer unit 2 corresponding to an image forming unit, and a paper feed unit 3. The scanner unit 1 sends image information of a document placed on the contact glass 11 to a color CCD image sensor (hereinafter, referred to as a color CCD) 13 by an optical scanning unit 12 having a light source, a plurality of mirrors, and a lens. The color CCD 13 separates the color into red R, green G, and black K, reads each color, and converts it into an electric image signal.
[0026]
The image signal separated into red R, green G, and black K is subjected to color conversion processing, converted into color components of black K, cyan C, magenta M, and yellow Y, and sent to the printer unit 2.
[0027]
The printer unit 2 has an image forming unit 21, a fixing unit 22, and a transfer paper transport unit 23. The image forming unit 21 includes a photoconductor 24, a revolver unit 25, a transfer unit 26, and a writing unit 27, as shown in FIG. The printer unit 2 includes a charge removing lamp 28, a charging charger 29, a revolver unit 25, a toner adhesion amount sensor 30, a charge removing lamp 31 before transfer, a transfer unit 26, and a drum cleaning unit 32 along the rotation direction of the photoconductor 24. Is provided.
[0028]
The revolver unit 25 includes developing devices 251, 252, 253, 254 for each color of black K, cyan C, magenta M, and yellow Y, and a revolver home position sensor 255.
[0029]
The transfer unit 26 is wound around a plurality of rollers and has an intermediate transfer belt 261 having a reference mark 262, a belt transfer charger 263, a mark sensor 264 for reading the reference mark 262, a paper transfer charger 265, and It has a belt cleaning section 266.
[0030]
The intermediate transfer belt 261 has, for example, a length twice as long as the length of A4 and twice as long as the circumference of the photoconductor 24 in addition to an interval between each transfer paper (paper interval). By two rotations, two screen images can be formed on the intermediate transfer belt 261 in the same color. A transfer roller 23 for transferring the transfer paper and a predetermined distance Lr from the registration roller 231 are disposed upstream of the transfer paper transport unit 23 provided on the upstream side of the paper transfer charger 265 to detect the leading end of the transfer paper. It has a leading end detection sensor S1 that performs the operation. The transfer paper corresponds to a recording medium.
[0031]
Next, the paper feed unit 3 shown in FIG. 1 will be described. The paper feed unit 3 has a plurality of paper feed trays 41, 42, 43. Each of the paper feed trays 41 to 43 has a paper feed claw 44 and a paper feed roller 45, and transfer paper detection sensors S2, S3, and S4 for detecting transfer paper are provided on the output side of the paper feed roller 45, respectively. Have been. The transfer paper fed from the paper feed unit 3 is sent to the transfer paper transport unit 23 by a transport roller 46 provided at an outlet of the paper feed unit 3.
[0032]
Next, a control unit of the image forming apparatus will be described with reference to FIG. The control unit 5 of the image forming apparatus controls the operations of the scanner unit 1, the printer unit 2, and the paper feed unit 3, as shown in FIG. The control unit 5 includes a central control unit 51 that displays an operation state and the like on the display unit 4, a transfer sheet interval detection unit 52, an operation mode change unit 53, and an image processing unit (hereinafter, referred to as IPU) 100.
[0033]
The transfer paper interval detection unit 52 receives transfer paper detection signals from the leading edge detection sensor S1 provided in the printer unit 2 and the transfer paper detection sensors S2, S3, and S4 provided in the paper supply unit 3. . In response to the input transfer paper detection signal, the transfer paper interval detection unit 52 determines that the rear end of the first transfer paper and the two Detects the distance from the leading edge of the transfer sheet fed to the sheet.
[0034]
The operation mode changing unit 53 is configured to operate when the interval between the first transfer sheet and the second transfer sheet detected by the transfer sheet interval detection unit 52 becomes longer than a predetermined reference value due to a delay in timing. In this case, the operation mode of two-chamfering is invalidated, and the operation mode is changed to an operation mode of forming an image on the intermediate transfer belt 261 one by one.
[0035]
The content of the processing when a full-color image is formed for one surface by the image forming apparatus configured as described above will be described again with reference to FIG.
[0036]
The image forming unit 21 rotates the intermediate transfer belt 261 of the photoconductor 24 and the transfer unit 26. Then, the image forming unit 21 starts reading black K image data at a predetermined timing after the mark sensor 264 of the transfer unit 26 detects the reference mark 262 of the intermediate transfer belt 261. The optical writing unit 27 forms an electrostatic latent image on the photoconductor 24 based on the black K image data.
[0037]
The electrostatic latent image formed on the photoconductor 24 is visualized by a black K developing unit 251 of the revolver unit 25. The visualized black image K is primarily transferred to the intermediate transfer belt 261 by the belt transfer charger 263 at a timing based on the reference mark 262 of the intermediate transfer belt 261 detected by the mark sensor 264.
[0038]
When the primary transfer of the first color black image K is completed, the revolver unit 25 rotates, and the cyan C developing device 252 comes into contact with the photoconductor 24. Thereafter, a cyan image C is formed on the photoconductor 24. The formed cyan image C is primarily transferred to the intermediate transfer belt 261 at a timing based on the detection of the reference mark 262 by the mark sensor 264, and the first color black image K and the second color cyan image C are superimposed. Is done. This image formation and primary transfer are repeated for each image of magenta M and yellow Y, and a full-color toner image is formed on the intermediate transfer belt 261.
[0039]
The full-color toner image formed on the intermediate transfer belt 261 is secondarily transferred by a paper transfer charger 265 to transfer paper sent from the transfer paper transport unit 23, and the transfer paper on which the full-color toner image has been transferred is transferred to the transfer paper. The sheet is sent to the fixing section 22 by the belt 33 and is fixed and discharged. A belt cleaning unit 266 is in contact with the intermediate transfer belt 261 that has secondary-transferred the toner image onto the transfer paper. Then, the toner remaining on the surface of the intermediate transfer belt 261 is removed by the belt cleaning unit 266 to prepare for the next image formation.
[0040]
When forming an image of one color, it is not necessary to superimpose toner images of different colors on the intermediate transfer belt 261, and thus image formation is started without particularly detecting the reference mark 262. In this image formation, writing, development, primary transfer, secondary transfer, and cleaning of the intermediate transfer belt 261 are sequentially performed at a predetermined timing. Further, even when a plurality of images are continuously formed, the image is formed at a required image interval regardless of the rotation of the intermediate transfer belt 261.
[0041]
Next, a description will be given of a case of a two-chamfer operation mode in which two full-color images are formed on the intermediate transfer belt 261. First, when the intermediate transfer belt 261 rotates and the mark sensor 264 detects the reference mark 262, a first black image K1 is formed on the photoconductor 24. As shown in the developed view of FIG. 4, the formed black image K1 is transferred to the intermediate transfer belt 261 by the belt transfer charger 263 at a timing based on the detection of the reference mark 262 of the intermediate transfer belt 261 by the mark sensor 264. Is primarily transferred.
[0042]
Subsequently, a second black image K2 is formed on the photoconductor 24. The formed black image K2 is primarily transferred to an area of the intermediate transfer belt 261 after the area where the black image K1 has been transferred. When the secondary transfer of the black images K1 and K2 of the first color is completed, the revolver unit 25 rotates to bring the cyan C developing device 252 into contact with the photoconductor 24. Then, the first cyan image C1 is formed on the photoconductor 24. The formed cyan image C1 is primarily transferred to the intermediate transfer belt 261 at a timing based on the detection of the reference mark 262 by the mark sensor 264. Then, the first color black image K1 and the second color cyan image C1 are superimposed.
[0043]
Thereafter, a second cyan image C2 is formed on the photoconductor 24. The formed cyan image C2 is primarily transferred to the intermediate transfer belt 261 and is superimposed on the black image K2. This image formation and primary transfer are repeated for each image of magenta M and yellow Y, and a first full-color image FC1 and a second full-color image FC2 are formed on the intermediate transfer belt 261.
[0044]
After the image formation of the image of yellow Y, which is the final color of the image FC1 on the first surface, is started, the registration roller 231 rotates at a fixed secondary transfer timing. Then, the first full-color image FC1 is secondarily transferred onto the transfer paper and fixed, and the second full-color image FC2 is secondarily transferred onto the transfer paper that is subsequently fed and fixed.
[0045]
The image forming control timing when the two images FC1 and FC2 are formed on the intermediate transfer belt 261 will be described with reference to FIG. La shown in FIG. 4 is the distance between the tip of the image FC1 on the first surface and the tip of the image FC2 on the second surface.
[0046]
If this La is kept constant regardless of the image length, that is, the length of the transfer sheet for secondary transfer, various image forming control timings can be simplified regardless of the transfer sheet size.
[0047]
The distance LD1 between the image FC1 on the first side and the image FC2 on the second side, that is, the interval between the two transfer sheets sent during the two-sided printing is the maximum transfer sheet length for the two-sided printing, for example, a length of A4 size. Or the short length of the LT size.
[0048]
The interval LD1 is determined to be an operable length according to the paper feed interval of the transfer paper, the return speed of the scanner unit 1, and the like. Further, the distance LD2 from the end of the image FC2 on the second side to the start end of the intermediate transfer belt 261 having the reference mark 262 is a portion that does not affect the paper interval of the transfer paper. The distance LD2 is determined by the color change speed of the revolver unit 25, the return speed of the scanner unit 1, and the like, and normally, LD1 = LD2.
[0049]
Next, the internal configuration of the IPU 100 will be described with reference to FIG. The image information of the document from the optical scanning means 12 is photoelectrically converted by the color CCD 13 and further converted into a digital signal by the A / D converter 61.
[0050]
The image signal converted into the digital signal is subjected to shading correction by a shading correction unit 62 and then to MTF correction and γ correction by an MTF correction / γ correction unit 63. The image signal that has passed through the scaling unit 72 that performs the scaling process is scaled according to the scaling factor, and is sent to the selector 64.
[0051]
The selector 64 switches the destination of the image signal to the writing γ correction unit 71 or the memory controller 65. The image signal that has passed through the writing γ correction unit 71 has its writing γ corrected in accordance with the image forming conditions, and is sent to the writing unit 57. The memory controller 65 and the selector 64 are configured to be able to bidirectionally input and output image signals.
[0052]
Although not specifically shown in FIG. 5, the IPU 100 includes, in addition to the image data input from the scanner unit 1, image data supplied from outside such as data output from a data processing device such as a personal computer. It has a function of inputting and outputting a plurality of data so that it can also process data. Further, a CPU 68 for setting the memory controller 65 and the like and controlling the scanner unit 1 and the writing unit 57, and a ROM 69 and a RAM 70 for storing programs and data thereof are provided.
[0053]
Further, the CPU 68 writes and reads data in the image memory 66 via the memory controller 65. The image data 73 can be bidirectionally input / output between the memory controller 65 or the CPU 68 and the display unit 4 via the I / O port 67.
[0054]
Next, the internal details of the memory controller 65 and the image memory 66 in FIG. 5 will be described with reference to FIG. FIG. 6 is a diagram showing the details of the individual storage devices of the storage means in the present embodiment, and shows that the image memory 66 is also connected to the individual storage devices.
[0055]
The memory controller 65 includes an input data selector 201, an image synthesizing unit 202, a primary compression / expansion unit 203, an output data selector 204, and a secondary compression / expansion unit 205. The setting of control data in each of these blocks is performed by the CPU 68. Note that the addresses and data in FIG. 5 are for the image data, and the data and addresses connected to the CPU 68 are not shown. The memory controller 65 and the CPU 68 correspond to a page memory number calculating unit, a grouping unit, and a page memory obtaining unit.
[0056]
On the other hand, the image memory 66 includes primary and secondary storage devices 206 and 207. The primary storage device 206 corresponding to the page memory has a data transfer speed required to write data to a designated area of the memory or to read data from a designated area of the memory when outputting an image when inputting / outputting image data. For example, a memory that can be accessed at a high speed, such as a DRAM, is used so that the operation can be performed substantially in synchronization with the operation.
[0057]
In addition, the primary storage device 206 is used for storing image data input to the image forming apparatus and image data output to the printer unit 2 that forms an image. The primary storage device 206 has an interface unit with a memory controller that can divide into a plurality of pages having a prescribed size and simultaneously execute input and output of image data.
[0058]
A secondary storage device 207 corresponding to the storage unit is a large-capacity nonvolatile memory for synthesizing and sorting input image data and storing the data. If the primary storage device 206 has a sufficient capacity for processing image data and is non-volatile, there is no need to input and output data to and from the secondary storage device 207.
[0059]
If the secondary storage device 207 can write / read data substantially in synchronization with the data transfer speed required at the time of image data input / output, the data can be directly written / read to / from the secondary storage device 207. Becomes possible. In such a case, data processing can be performed without distinction between primary and secondary.
[0060]
If the secondary storage device 207 cannot write / read data almost in synchronization with the data transfer speed required at the time of image data input / output, for example, the secondary storage device 207 may have a storage medium such as a hard disk or a magneto-optical disk. Is used, the input / output of data to / from the secondary storage device can be processed according to the data transfer capability of the secondary storage device 207 via the primary storage device.
[0061]
Here, a specific use example of the primary storage device 206 and the secondary storage device 207 in each application will be described.
[0062]
Example 1 One copy in copy application
In the case of one copy, first, image data from the scanner unit 1 is input to the primary storage device 206. Then, the image data is output to the image forming unit 21 at substantially the same timing. When the image formation ends normally, the image data stored in the secondary storage device 207 is deleted without being used. However, in the event of a jam or the like, an image can be formed by reading image data from the secondary storage device 207.
[0063]
Example 2 Sorting in copy application (multiple copy)
In the case of two or more copies, first, image data from the scanner unit 1 is input to the primary storage device 206. For the first copy, image data is output from the primary storage device 206 to the image forming unit 21 as in Example 1, and the image data is also stored in the secondary storage device 207 at the same time.
[0064]
The image data of the second copy and thereafter is output from the secondary storage device 207 to the primary storage device 206 and to the image forming unit 21, so that the scanner unit 1 does not need to read the second copy and thereafter. When the necessary number of copies are completed, the image data stored in the secondary storage device 207 is deleted.
[0065]
Example 3 Image storage from a scanner
In this case, the image data from the scanner unit 1 is stored in the secondary storage device 207 via the primary storage device 206. At this time, the image data remains stored unless intentional erasure is performed.
[0066]
Example 4 Printing from an external input device (for example, a personal computer)
This case is almost the same as in Examples 1 and 2, and the input source of the image data is not the scanner unit 1 but the external input device.
[0067]
Example 5 Image storage from external input device
In this case, the process is almost the same as in Example 3, and the input source of the image data is not the scanner unit 1 but the external input device.
[0068]
Example 6 Printing stored images
When printing the images stored in Examples 3 and 5, the images are printed by the secondary storage device 207, the primary storage device 206, and the image forming unit 21.
[0069]
Next, an operation example of the memory controller 65 will be described. Here, an example is shown in which the secondary storage device 207 cannot write / read data substantially in synchronization with the data transfer speed required at the time of image input / output.
[0070]
First, storage in the image memory 66 by image input will be described.
[0071]
The input data selector 201 selects image data to be written into the primary storage device 206 in the image memory 66 from a plurality of data. The image data selected by the input data selector 201 is supplied to the image synthesizing unit 202, where the image data is synthesized as needed. The image data processed by the image synthesizing unit 202 is compressed by the primary compression / decompression unit 203, and the compressed image data is written to the primary storage device 206.
[0072]
The image data written in the primary storage device 206 is further compressed by the secondary compression / decompression unit 205 as necessary, and then stored in the secondary storage device 207.
[0073]
Next, image data output, which is reading from the image memory, will be described.
[0074]
When the image data is output, the image data stored in the primary storage device 206 is read. When the image data to be output is stored in the primary storage device 206, the primary compression / expansion unit 203 expands the image data in the primary storage device 206. The decompressed image data or the image data obtained by synthesizing the decompressed image data and the image data of the input image data is selected by the output data selector 204 and output.
[0075]
When the image data to be output is stored in the secondary storage device 207, the output target image data stored in the secondary storage device 207 is decompressed by the secondary compression / decompression unit 205. After the decompressed image data is written in the primary storage device 206, the above-described image data output operation is performed.
[0076]
Next, input / output control of image data using the page memory will be described. The page memory is configured in the primary storage device 206, and temporarily stores image data in page units.
[0077]
Further, the size of the normal page memory changes according to the resolution or the like, but the memory capacity of the A4 size unit is managed as one page unit. For example, when there is an input of A3 size, image data is input using two pages of the page memory. Further, in the case of color input, image data of magenta M, cyan C, yellow Y, and black K, which are color components of the color, are input from the scanner unit 1 to the page memory for each color component.
[0078]
The same applies to the output. If the color component to be printed exists in the page memory, the image data developed on the page memory is output to the printer unit 2. If the color component of the designated image data does not exist on the page memory but exists in the secondary storage device 207, the designated image data is first read from the secondary storage device 207 onto the page memory, and then the image data is transferred to the printer. Output to the section 2. In the case of a color copying machine, there is a so-called ACS (Auto Color Select: automatic color selection) mode function of automatically judging the color of an image of a document and performing copying in either black and white or full color. Further, the size of the document and the size of the transfer paper to be output are automatically determined or set, or set by an operator. The size can be referred to by the CPU 68.
[0079]
Hereinafter, an operation in a case where a page memory is acquired without considering grouping of page memories will be described.
[0080]
7 and 8 are explanatory diagrams showing an example in which a page memory is obtained without considering the grouping of the page memories in the input / output page memory acquisition. Here, ten page memories are mounted. Further, one page memory is an example in which a memory size capable of inputting A4 image data is allocated.
[0081]
FIG. 7 shows a case where there is an A3 color input (M, C, Y, K). At this time, since an A3 document is input, two page memories are used for one color component. In this example, two page memories, the second and third page memories, are acquired at the time of acquiring the page memory of the M component. In addition, two page memories of the fifth and sixth page memories are acquired for the C component, and two page memories of the eighth and ninth page memories are acquired for the Y component.
[0082]
Next, an attempt is made to acquire two page memories of the K component. However, although the number of free page memories is 1, 4, 7 and 10, the four free page memories exist discontinuously, these four page memories exist discontinuously. It is not possible to obtain two consecutive page memories for components.
[0083]
When grouping is not taken into consideration so that the number of groups of page memories is maximized, the page memory 7 is discontinued, but the page memory 7 is in use, although there are available page memories. Has not been utilized.
[0084]
If the page memory management is performed without considering the grouping of the page memories as described above, the acquisition of the page memory fails even though there is a page memory with a free space. As a result, a page memory acquisition wait state occurs, which causes a decrease in productivity. Therefore, efficient processing becomes possible by considering the grouping of page memories.
[0085]
FIG. 8 shows a second example in which a request for output (A3 color) from the page memory is received during input to the page memory (A3 color). As in FIG. 7, the acquisition process of the page memory with the M component at the time of input is performed without considering the grouping of the page memories, and as a result, the acquisition of the page memory at the time of output occurs.
[0086]
FIG. 8 shows a state where the input of the image data of the image number 2 occurs while the image data of the image number 2 is stored in the page memory.
[0087]
As shown in FIG. 8, in a state where the image data of the image number 2 is stored in the page memory, the fourth and first pages of the page memory are vacant. However, since these page memories are not continuous, they cannot store image data of image number 1.
[0088]
Therefore, after the second and third page memories are released, the first to fourth page memories can be obtained and stored.
[0089]
9 and 10 are flowcharts showing a control procedure of page memory acquisition in consideration of grouping of page memories. FIG. 9 is a flowchart showing a procedure of page memory acquisition processing.
[0090]
In this process, if there is an image data input / output request in step S10, the CPU 68 proceeds to the page memory acquisition process in step S12 and thereafter. In step S12, the CPU 68 acquires the image number and color component of the requested image data. Here, the description will be made on the assumption that an image input request for a color component is generated for the same image number. In step S13, the CPU 68 determines whether or not the page memory has already been acquired with the image number for which the input page memory request was made. If it has been acquired, return.
[0091]
On the other hand, if the acquisition has not been completed in step S13, the CPU 68 performs acquisition processing and processing in the event of an acquisition failure in steps S14 to S19. In step S14, the CPU 68 calculates the number of page memories acquired this time by the memory controller 64. In particular,
The number of page memories to be obtained by performing the calculation of (input / output image data size) / (size of one page memory) is calculated, but if it is not divisible, it is obtained by the above calculation because of the fractional image data size. The number of page memories is obtained by adding 1 to the quotient.
[0092]
After calculating the number of page memories to be acquired in this way, the CPU 68 executes a page memory acquisition subroutine of step S15. FIG. 10 is a subroutine of the page memory acquisition processing in step 15. This subroutine is a process of actually acquiring a page memory in consideration of grouping.
[0093]
First, grouping will be described. For example, when the number of mounted page memories is 10, the page memory numbers are 1 to 10, and the calculated number of page memories is 2, the CPU 68 sets the page memories to 1-2, 3-4, 5-6, and 7-8. , 9-10. Then, the CPU 68 searches for a usable group and acquires the page memory of the page memory group.
[0094]
A general process of this grouping will be described. Assuming that the calculated number of page memories is m, the CPU 68 groups m successive page memories from the page memory having the same page memory number as 1 using m as one group.
[0095]
For example, a case where the calculated m is 3 will be described. Natural numbers congruent with 1 modulo 3 are (1, 4, 7,...). That is, three consecutive page memories are one group from the natural number of page memory numbers determined by an arithmetic progression with the first term being 1 and the tolerance being 3. By grouping in this way, the number of groups is the largest among the possible numbers of combinations that can be grouped in three consecutive page memories.
[0096]
The flowchart will be described. First, the CPU 68 resets the page memory in step S30, and sets a page memory search counter to 1. The next step S31 is processing in which the CPU 68 determines whether or not the group of the page memory has been used for all the groups. If the processing has been performed for all the groups, the CPU 68 ends the processing of this flowchart.
[0097]
In step S32, the CPU 68 determines whether or not (i-1)% GetPageNnm == 0. This expression is an expression in the C language, and means that the remainder obtained by dividing (i-1) by GetPageNnm is equal to 0. That is, the above equation means that i is equal to 1 modulo GetPageNnm. Here, GetPageNnm is the calculated number of page memories, and is 2 for A3.
[0098]
Therefore, if the formula of step S32 is established, the page memory number i becomes the head of one group. Therefore, if the formula of step S32 does not hold, the CPU 68 performs the process of step S38 in order to obtain the head of the group.
[0099]
In step S38, the CPU 68 increments the loop counter i in order to search the next page memory, and the process proceeds to step S31 again.
[0100]
Thereafter, the CPU 68 initializes the page memory continuous acquisition monitoring counter in step S33, and checks whether the [i + k] th page memory is usable. If the page memory is unusable, the CPU 68 searches for the next page memory in step S38. Then, the process returns to step S331.
[0101]
If the CPU 68 succeeds in continuously acquiring the page memory in step S32, the CPU 68 sets the page memory continuous acquisition monitoring counter to 0 in step S33. Then, in step S34, the CPU 68 checks whether or not the i-th page memory can be continuously used.
[0102]
If not usable, the CPU 68 increments i by 1 in step S38 and repeats the same processing from step S31 for the next page memory.
[0103]
If it is possible to use the (i + k) th page memory in step S34, the CPU 68 increments the page memory number by one in step S35 and searches for a page memory having the next larger page memory number. Then, the CPU 68 checks whether or not two available page memories have been continuously obtained in step S36.
[0104]
If continuous acquisition has not been performed, the CPU 68 performs the process of step S34 again. If the page memory can be continuously obtained, the CPU 68 sets the page memory to a usable state in step S37 and returns.
[0105]
When the CPU 68 executes the page memory acquisition process in the subroutine of step S15 in this way, it is determined in step S16 whether the page memory has been acquired in the page memory acquisition process of step S15. If acquired, in step S17, the CPU 68 performs an acquisition process of the page memory. If the acquisition fails, the CPU 68 suspends the current input / output execution request because the page memory could not be acquired in S18.
[0106]
Then, entry is made in the page memory empty wait notification queue in step S19, a notification is made when other input output ends and page memory empty occurs, and reacquisition processing can be performed in step S11.
[0107]
By performing control as described above, a page memory acquisition process in consideration of grouping of page memories can be realized, and page memory resources can be effectively used, so that highly productive page memory management can be provided.
[0108]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a memory control device, a memory control method, and an image forming apparatus capable of improving the use efficiency of a page memory.
[Brief description of the drawings]
FIG. 1 is a configuration diagram illustrating a schematic configuration of an image forming apparatus according to an embodiment of the present invention.
FIG. 2 is an enlarged configuration diagram illustrating an image forming unit of the image forming apparatus of FIG. 1;
FIG. 3 is a block diagram illustrating a configuration of a control unit of the image forming apparatus of FIG. 1;
FIG. 4 is a development view showing two images formed on the intermediate transfer belt.
FIG. 5 is a block diagram illustrating an internal configuration of the image processing unit in FIG. 3;
FIG. 6 is a block diagram showing an internal configuration of a memory controller and an image memory in FIG. 5;
FIG. 7 is an explanatory diagram showing an example in which a page memory is acquired without considering grouping of page memories in input / output page memory acquisition.
FIG. 8 is an explanatory diagram showing another example in which a page memory is acquired without taking into account grouping of page memories in acquiring an input / output page memory.
FIG. 9 is a flowchart illustrating a procedure of a page memory acquisition process.
FIG. 10 is a flowchart showing details of S15 in FIG. 9;
[Explanation of symbols]
65 Memory Controller
65a Data input / output control unit
66 Image memory
68 CPU

Claims (9)

In an image forming apparatus that performs control for storing image data by using a memory area in which a plurality of page memories having a prescribed size are continuously arranged,
A page memory number calculation unit for calculating the number of page memories required to store the image data,
Grouping means for grouping the page memories for each page memory continuous by the number of page memories calculated by the page memory number calculation means;
An image forming apparatus comprising: a page memory acquisition unit that acquires the page memory in a group of page memories grouped by the grouping unit. 2. The image forming apparatus according to claim 1, wherein the number of groups of page memories grouped by the grouping unit is the largest among the number of groups that can be grouped. 3. The image according to claim 1, wherein the page memory is used for storing image data input to the image forming apparatus and image data output to an image forming unit that forms an image. Forming equipment. 4. The image forming apparatus according to claim 1, wherein the page memory number calculation unit calculates the page memory number based on the number of color components of the image data. 5. 5. The number of page memories according to claim 1, wherein the page memory number calculation unit calculates the number of page memories based on the number of color components required to form the image data on a recording medium. 2. The image forming apparatus according to claim 1. The image forming apparatus according to claim 1, wherein the page memory number calculation unit calculates the page memory number based on a size of the image data. The image forming apparatus according to claim 1, further comprising a storage unit configured to store the input image data via the page memory. In a memory control device that performs control for storing image data by using a memory area in which a plurality of page memories having a specified size are continuously arranged,
A page memory number calculation unit for calculating the number of page memories required to store the image data,
Grouping means for grouping the page memories for each page memory continuous by the number of page memories calculated by the page memory number calculation means;
A memory control device, comprising: a page memory acquisition unit that acquires the page memory in groups of page memories grouped by the grouping unit. A memory control method for performing control for storing image data by using a memory area in which a plurality of page memories having a prescribed size are continuously arranged,
A page memory number calculation step of calculating a page memory number required to store the image data,
A grouping step of grouping the page memories for each continuous page memory of the number of page memories calculated in the page memory number calculation step;
A page memory acquisition step of acquiring the page memory in groups of page memories grouped by the grouping means.

Images