JPH06105100A - Picture processor - Google Patents

Abstract

PURPOSE:To provide the picture processor which improves the system reliability by effectively and quickly storing a compressed picture signal in a memory to prevent an error like memory overflow. CONSTITUTION:The picture processor consists of an image reader 12 which inputs picture data in the unit of a page, a compressor 14 which compresses picture data from the image reader, an expander 15, a picture memory 18 where compressed picture data is stored, and a control circuit 17 which is connected to these devices and controls them. When the memory 18 has plural storage available areas, compressed picture data is written in a maximum storage available area out of these areas; and when the data size of the picture is settled after the end of compression, data is copied to and stored in an optimum storage available area of the memory 18 in accordance with the data quantity of the compressed picture.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for electrically handling image data, such as a copying machine or a facsimile, and more particularly to compressing image data for encoding and storing image data stored in a storage device. The present invention relates to an image processing device that effectively handles an image memory when handling.

[0002]

2. Description of the Related Art In a conventional image processing apparatus having an image storage means, a storage device is used to store image data input page by page from an image input means, and the storage device preferably has a large capacity. Since a high processing speed is required, a storage device such as a semiconductor memory is used.

By the way, with the resolution of 400 dpi, A3
An image signal of about 4 Mbytes is used to represent a size image with a binary signal. Therefore, in order to store this image signal, a memory having a storage capacity of at least the same number of bytes is required, and in order to store images for a plurality of sheets, a capacity twice that number is naturally required. Therefore, it is possible to compress the image when storing the image. According to this, a general image data amount can be reduced to about 1/10, and a plurality of images can be stored in a memory having a relatively small capacity. However, the amount of information after compression is uncertain because it depends on the image content, and the storage area of the storage means necessary for storing this is also uncertain. Therefore, it may not fit in the prepared storage area.

In general, when image data is stored in a memory, an image reading operation or a printout operation can be continuously performed on one image in time (for example, rotation of a photosensitive drum in a copying machine). It is difficult to control the speed arbitrarily.) Therefore, one image is stored in a continuous storage area on the memory.

Therefore, as described in JP-A-61-176261, when a plurality of storable areas are present in the storage means, the storage area is selected according to each storable amount. There is something. Here, in a system in which the operation of compressing the input image data and the operation of storing the compressed image data in the storage device are simultaneously performed, the data amount of the compressed data cannot be determined until the compression is completed. When there are multiple storable areas, the largest storage area of the plurality of storable areas is preferentially selected to perform image storage, thereby preventing overflow in the storage means and destruction of image signals. I am trying to do it.

[0006]

However, the compressed data is stored in an area having the maximum storable area regardless of the size of the compressed data, or a unique process similar to this is performed. However, the image memory cannot be used to the maximum extent. When the maximum storage area is selected and stored, the area is divided, and the maximum storage area becomes smaller and smaller. Therefore, there are many opportunities to cause a memory overflow or the like, which causes the device to stop or to perform exception processing for recovery, resulting in a decrease in operating efficiency of the entire device.

The present invention has been made in view of the above points. Therefore, an object of the present invention is to effectively and quickly store a compressed image signal in a storage means and prevent an error such as a memory overflow as much as possible. The object of the present invention is to provide an image processing apparatus which improves the reliability of the system.

[0008]

According to the present invention, there is provided input means for inputting image data in page units, means for compressing image data from the input means, and storage capable of storing compressed image data for a plurality of pages. And a storage management unit that manages management data relating to the storage unit.

[0009]

According to the present invention, with the above construction, the address of the area having the maximum storable amount stored in the storage managing means at the time of inputting the image data becomes the temporary storage destination after compression. Here, the image data is stored in the storage means together with the compression operation, and this temporary storage destination address becomes the start address of the area having the maximum storable amount among the plurality of storable areas, and this area is stored by the storage management means. It becomes a memory non-permitted area. Therefore, in order to prevent overflow when temporarily storing at the same time as compression, when the storage amount of the area with the maximum storable amount is less than the raw data amount of the input image data before compression, start image input. It is also possible to improve the reliability of the device by performing control not to perform it.

At the time when the data amount of the compressed image is defined after completion of the compression and accumulation, the storage management means searches for the address of the smallest storable area that exceeds the determined data amount after image compression according to the compressed image data amount. The data temporarily stored in the maximum storable area is copied to the storable area. Simultaneously with the start of data copying, the maximum storable area changes from the storage non-permitted state to the storage permitted state, and the next page can be stored.
If the optimum storage area is the same as the temporarily stored storage area, the data is not copied, the storage area remains in the storage disapproved state, and the storage area where the compressed image data is stored is not stored. It is managed by being divided into a permitted area and a storable area starting immediately after the storage area.

By performing the control as described above, it is possible to provide an apparatus which performs image processing to an optimum area with a quick and simple structure and a minimum memory capacity.

[0012]

EXAMPLES The present invention will be described below with reference to examples. Figure 1
FIG. 3 is a block diagram of a basic configuration of an embodiment of the present invention. Figure 1
In the image processing apparatus shown in FIG. 1, reference numeral 12 denotes an image reading apparatus that reads a document page by page and outputs image data.
Reference numeral 1 is an automatic document feeder (ADF) that feeds documents one by one to the image reading device 12, and 14 is a compressor that compresses and encodes input image data and outputs compressed image data.
Reference numeral 5 denotes a decompressor for decompressing and inputting the compressed image data and outputting the image data, 18 denotes an image memory capable of storing a plurality of compression-coded compressed image data, 19
Is an image recording device for forming an image on a recording material based on the image data output from the decompressor 15 and recording the image. Reference numeral 17 is a control circuit for controlling each of the above devices.

Reference numeral 16 is a data bus for transferring data among the compressor 14, the decompressor 15 and the image memory 18.
The compressor 14, the decompressor 15, the data bus 16, the control circuit 17, and the image memory 18 constitute the image processing device 13. An operation input unit (UI) 20 includes a numeric keypad and function keys, and includes a file name of an original document for desired correction such as addition, replacement, and deletion, original document information of several pages, and start of correction processing of these. This is a device for performing various inputs such as termination.

The control circuit 17 has a built-in CPU,
It is provided with a ROM for controlling the entire apparatus and for storing a program and a RAM for storing management data of a memory necessary for control. Further, the control circuit 17 is divided into a memory control section for controlling the image memory and a system control section for controlling the operation of the system. When writing the image data to the image memory, the memory control unit searches for empty areas in the image memory, stores the leading addresses of these empty areas, and connects them to create a chain of empty areas. Further, when the compressed image data from the compressor is written into the image memory to create data in page units, the system controller is notified of the start address and end address of the data file.

The control unit of the system is a ROM for storing a program for executing a CPU for controlling the system, a primary storage for data for operating the system, and a data for inputting data from an image reading device to a compressor. It consists of RAM required for buffering, and controls the operation of the entire device. Next, FIG. 2 will be described.

FIG. 2A shows an image memory management table (M
An em-Table (Memory-Table) is shown. The image memory management table is a table for managing the storage area of the image data of the document stored in the image memory and the empty area in which nothing is stored. The image memory management table stores the system state indicating the state of the image memory, the temporary storage address for storing the temporary storage address, the temporary storage area size indicating the size of the temporary storage area, and the optimum size for the compressed image data. An optimum area address indicating the address of the storage permitted area and a Mem for managing an empty area where nothing is stored or no longer needs to be stored.
-Emp-mem-Q (Empty-memory-node-Q) for queuing Node (Memory-Node (memory node))
ueue (empty memory node sequence)) and M for managing the storage area of the image data of the original document stored in the image memory
Exec-mem-Q (E for queuing em-node
xecute-memory-node- Queue (execution memory node sequence))
And Input-end-flg (Input-end
-flag (input operation end flag), Output-end-flg (Output-end-flag (output operation end flag)) indicating the end of the output operation, and the end of the copy operation from the temporary storage area to the optimum storage area Copy-end-flg (Copy-end-flag
(Copy operation end flag)).

The memory node is a node in which management information such as an address for one page of the storage area of the image data of the original document stored in the image memory or the empty area in which nothing is stored is stored. FIG. 2B shows a memory map of a memory node. The node link is used for queuing a plurality of node links, the file identification such as a file name for identifying a file, the deletion, the transmission, File status management indicating presence / absence of print, copy request, etc., page number indicating page number, original area start address indicating which address in the image memory the writing is started, area end indicating original end It has an address, a storage area size that indicates the amount of data in the area, and U / I (User Interface) information that stores a command from the operator. Such a node is created for each page of the document to be stored and for each empty area on the memory.

FIG. 4 is a flow chart showing the operation of the apparatus constructed according to FIG. Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The document is set and UI20
When the copy key is pressed by the operator, the image reading device 12 performs the initial setting necessary for the copy operation, such as the number of sheets instruction, the paper size instruction, and the image output instruction to the control circuit 17, and the instruction from the control circuit 17 The image reading device 12 starts reading a document.

The image data output from the image reading device 12 is encoded by the compressor 14 and, at the same time, stored in the image memory 18. The address on the memory when the compressed image data is stored in the memory is stored in the temporary storage address area of the image memory management table.
FIG. 3 is a diagram showing a storage state of the memory. On the left side, memory addresses are continuously present in the range of 0 to M-MAX. Here, M-MAX indicates the maximum value of the address in this memory, and the area surrounded by the mesh line indicates that valid data already exists.

As shown in FIG. 3A, when no image is written in the image memory, the temporary storage address is initialized to the leading address of this empty area.
Moreover, one memory node is not connected to Exec-mem-Q of the image memory management table. See also Emp-mem-Q
A memory node is connected to. The start address of this empty area is set to the area start address of the memory node, M-MAX is set to the area end address, and M-MAX is set to the storage area size. This indicates the maximum empty area of the memory. By setting the area start address and the storage area size, it is possible to judge the success or failure of the memory writing of the compressed image, and it is possible to protect the image data previously written.

When an image of an A4 size original is read, a memory node is newly generated for the image stored in the memory A as shown in FIG. 3B, information on which mode the image was compressed, and the compressed image. Of the document size, the area start address of the memory A, the area end address of the memory A, and the data size of the area of the memory A are stored and linked to Exec-mem-Q of the image memory management table. Also,
For the remaining empty area, the area start address of the memory node of Emp-mem-Q is added by the amount of data from 0 to A.

Here, when the compressed image data of A is read out, decoded by the decompressor 15 and output by the image processing apparatus, the image memory as shown in FIG. The image scale management table and the memory node are changed so as to become (a). Now, let us consider a case where the state of the image memory has a plurality of empty regions as shown in FIG. At this time, the Emp of the image memory management table
An empty area, an empty area, and a memory node for the empty area are queued in -mem-Q. Also, Exec-
Memory nodes for areas B and C where images are stored are also queued in mem-Q. (Final area address of area C + 1) is stored in the temporary storage address of the image memory management table.

Here, when the image data of the original is read by the image reading device and stored in the image memory through the compressor, the storage destination of the image data is stored from the beginning of the empty area, but the storage is completed after the compression. At the stage when is completed, the one having the optimum area for the image data amount of the compressed image is determined from the three empty areas, and the image data is copied to the selected area. If the empty area is selected, the image data accumulated in the empty area is copied to the empty area and becomes as shown in FIG. At this time, the memory node for the empty area queued in Emp-mem-Q of the image scale management table is removed and
It is queued in c-mem-Q. Until the copy starts, the empty area is temporarily in the memory non-permitted state, but when the copy starts, it returns to the memory permissible state, so it becomes possible to store the image data of the next page. Data is not accidentally erased because it is faster.

Depending on the compression ratio of the image, the selected empty area may be an empty area, that is, a temporary storage area. In that case, as shown in FIG. 3E, the image scale management table is temporarily stored. The address area is shown in Figure 3.
It is changed to the top address of the empty area in (e). In this way, the accumulation is repeated until the image memory overflows until the image accumulation of the final document is completed. Here, if the amount of the compressed image data exceeds the capacity of the compressed image data storage area and cannot be stored in the empty area of the image memory, an image compression error occurs and the image data cannot be written. The memory area is set as an empty area, and the output of the image from the memory is prohibited, and the fact is displayed on the display unit of the UI.

[0025]

As is apparent from the above description, according to the present invention, when the image data is input, the storage management means finds the address of the area having the maximum storable amount, and The area pointed to becomes the temporary storage destination after compression. Here, the compression operation and the storage operation are performed at the same time, and the compressed image data is stored in the area having the maximum storable amount. At the same time, when the amount of stored data is determined after the compression is completed, the address of the storable area most suitable for the amount of data is searched by the storage management means, and the data temporarily stored in the maximum storable area is stored in the optimum storage. Data is copied to the feasible area. Simultaneously with the start of data copying, the maximum storable area changes from the storage non-permitted state to the storage permitted state, and the next page can be stored. When the optimum storage area is the maximum storable area, no data is copied and the storage area remains in the storage disapproval state. By performing control in this manner, it is possible to provide a device that performs image processing to an optimum area with a quick and simple structure and a minimum memory capacity.

Further, when the area having the largest storage capacity among the storable areas is smaller than the original image data quantity before compression, the memory overflow is prevented by not activating the input of the image data, and an error exception occurs. Opportunities for processing can be reduced as much as possible.

[Brief description of drawings]

FIG. 1 is a block diagram of a basic configuration showing an embodiment of the present invention.

FIG. 2 is a block diagram of an image memory.

FIG. 3 is a diagram showing a storage state of a memory.

FIG. 4 is a flowchart showing an embodiment of the present invention. 11 Automatic Document Feeding Device 12 Image Reading Unit 13 Image Processing Device 14 Compressor 15 Decompressor 16 Data Bus 17 Control Circuit 18 Image Memory 19 Image Output Device 20 Operation Input Unit

Claims (1)

[Claims] 1. Input means for inputting image data in page units, means for compressing image data from the input means, storage means capable of storing compressed image data for a plurality of pages, and management relating to the storage means. When there are a plurality of storable areas, the compressed image data is written and compressed at the same time as compression in the area having the maximum storable amount in each area. After completion, when the data size of the compressed image is determined, the image processing apparatus is controlled to copy the compressed image data to an optimum storable area according to the data amount of the compressed image.