JPH08153040A - Picture file device - Google Patents

Abstract

PURPOSE: To improve the efficiency of reading a picture disk. CONSTITUTION: The picture file device reproducing and displaying picture data of a disk specified from a host computer 1 is provided with a cache buffer memory 3 (a buffer, hereafter) holding the volume parts, the directory parts and the reference parameter parts of disks 81 to 8n, a buffer managing table 4 managing the address of each part and a disk exchange detecting means 11. At the time of reading picture data, the managing table is referred to and when data of each part does not exist on the buffer, access is given to a specified disk to read data to be held in the buffer. When data of each part exists on the buffer, the disk exchange detecting means 11 detects the presence of disk exchange. When disk exchange does not exist, data on the buffer is read but when disk exchange exists, data on the buffer of the disk device is canceled, and data is read from a disk and held in the buffer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magneto-optical disk or a CD-R in which a large number of still image data are compressed and recorded.
The present invention relates to an image file device for reproducing and displaying desired still image data from a removable disk such as an OM.

[0002]

2. Description of the Related Art Conventionally, a still image is converted into a digital signal, and a JPEG method is used to read a magneto-optical disk or a CD
BACKGROUND ART Exhibition-type high-definition still image disk systems, which are compressed and recorded in a ROM, and which combine a plurality of recorded still images and play back as a grouped work, are widely used in museums and the like.

In such a system, the type of disc,
The recording format, etc. is stipulated as an exhibition-type HDTV still image disc system technical guideline (HDTV Diffusion Support Center), and the image disc logical format consists of a volume part, a directory part, a reference parameter part, and a data part. .

FIG. 2 is a conceptual diagram of a logical format configuration. There is one volume part at a fixed sector address, and is a part where the disc identification and the management information of the image data recording area are recorded. The directory portion is a portion for recording the sector address where the image data is recorded, and the identification of the image data is based on the number determined in the order of recording in the directory.

The reference parameter section is a section for recording a compression parameter commonly used in the disc when an image is reproduced and displayed, and is recorded at a fixed sector address.
In the image data section, the substance of the image data including the header is recorded. An image file device for reproducing and displaying image data designated by a command from a host computer by using a plurality of the above-mentioned image discs and a plurality of disc devices, and a disc device number n and an image number to be reproduced from the host computer. When m is input, the disk mounted in the disk device number n is accessed, the volume section is first read, and the address and size of the directory section are acquired from the management information section in the volume.

Next, the acquired address of the directory portion is accessed, the acquired size is read, and the address of the data of the input image number m is acquired by reading the m-th address from the head of the directory portion. Access the address in the data section and read the header first. The image data describes the type, size, etc. of the image. If it is compressed data, read the reference parameter section and set the parameter in the decoding section for decompression,
The actual part of the image data is read, decompressed, and reproduced and displayed.

Usually, when a plurality of discs are loaded, the user specifies the disc device number from the host computer in order to identify the disc loaded in each disc device, and the disc device is loaded in the disc device. Read the volume part of the disc, and know the disc identification information. The user knows the disc device number in which the disc to be reproduced is mounted, and inputs the disc device number and the image number into the host computer to reproduce and display the image.

[0008]

SUMMARY OF THE INVENTION In the above method,
When reading the image data, the disk is always accessed to obtain the address of the image data, the volume part is read, and then the directory part is accessed. That is, three accesses to the disk, that is, the volume part, the directory part, and the reference parameter part, occur before the actual image data is accessed. The reproduction and display of the image data of the image filing apparatus is required to be as fast as possible, but access to a magneto-optical disk or a CD-ROM is generally slower than that of a hard disk, and it is desirable to reduce access to the disk.

In order to solve the above-mentioned problems, a memory is provided in the image filing apparatus, and after the disc is loaded and before the image is read, the volume part, the directory part and the compression parameter part of all the discs are stored in the memory in advance. A configuration is conceivable in which the volume part, the directory part, and the compression parameter part are read from the memory when reading and holding the image and reading the image, but the volume part, the directory part, and the reference parameter are stored in the memory each time the disk is replaced. An operation of inputting a command for newly reading a copy from the host computer occurs, resulting in an operation overhead.

The present invention is to solve the above-mentioned problems.
An object of the present invention is to provide an image filing apparatus that minimizes disk access, reads an image, and processes commands for accessing other disks at high speed.

[0011]

In order to solve the above problems, according to the first invention of the present application, a plurality of disk devices to which a plurality of disks can be attached and detached and a host computer are provided, and instructions from the host computer are provided. A cache buffer memory that holds, for each disk, the volume part, directory part, and reference parameter part of the disk necessary to read the image data in the image file device that reads, decodes, and displays the image data of the specified disk. And a command for reading and reproducing and displaying an image from a disk, a cache buffer management table that manages the addresses on the cache buffer memory of each part that it holds, and a disk exchange detection means in the disk device, or a volume part of the disk, and a directory. Part, reference para If the command for reading one of the over data unit is issued from the host computer,
If the necessary data of each part corresponding to the designated disk does not exist in the cache buffer memory by referring to the management table, the designated disk is accessed, the necessary parts are read into the cache buffer memory, and the management table is read. Update, if each of the necessary units are present in the cache buffer memory, the presence or absence of disk replacement of the disk device is detected, and if there is no replacement, read the relevant data of the necessary units on the cache buffer memory, When a disk replacement is detected, discard all data on the cache buffer memory of the disk,
It is provided with means for accessing the disk, newly reading the necessary parts into the cache buffer memory, and updating the management table.

In the second invention of the present application, there is provided means for reading out the volume part, the directory part and the reference parameter part of all the disks mounted when the power is turned on, holding them in the cache buffer memory, and validating the management table. Be prepared.

[0013]

According to the present invention, in the above construction, if there is no data portion necessary for the cache buffer in the image reading command or the command for accessing the disk, the disk is actually accessed to access the volume portion, the directory portion and the reference parameter. The necessary data part of the copy is read and held in the cache buffer, and the command is executed. If the cache buffer holds the required data,
First, the presence or absence of disk replacement is detected, and if replacement is not detected, the data in the cache buffer is regarded as the same as the content of the installed disk, the command is executed using the data in the cache buffer, and the replacement is detected. In this case, the contents of the cache buffer are regarded as invalid and discarded, and the newly required data section is read from the disk, held in the cache buffer, and the command is executed. In other words, only the read command or access command to the disc for the first time after mounting the disc causes access to the disc to read the volume part, the directory part, and the reference parameter part, and the subsequent access to the disc. Read or access command does not cause access to the above data part,
Disk access can be minimized, and images can be read and commands for accessing other disks can be processed at high speed.

Further, it is possible to provide an image filing device in which a user can issue a read command or a disc access command without being aware of disc exchange.

[0015]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the construction of an embodiment of an image filing apparatus according to the first and second aspects of the present invention. Only the essential parts relating to the present invention are shown and the other parts are omitted. In FIG. 1, reference numeral 1 is a host computer to which commands such as an image display command and a disc identification information display command are input. A controller unit 2 interprets a command issued from the host computer 1 and controls each unit.

Reference numerals 81 to 8n are n disk devices,
They are identified by device numbers d1 to dn, respectively. 91
9n are removable image discs such as magneto-optical discs and CD-ROMs that can be mounted in any of the disc devices 81-8n, and up to n discs can be mounted in each disc device at the same time. The logical format of these image disks has the configuration of FIG. 2 shown in the conventional example.

Reference numeral 3 denotes a cache buffer memory for holding a volume portion, directory portion, and reference parameter portion read from the image disc, and 4 denotes a volume portion, directory portion, reference parameter for each image disc held in the cache buffer memory 3. It is a cache buffer management table that manages the head address of each copy.

Reference numeral 11 denotes a disk exchange detection means, which is used when the host computer 1 issues a command to read out any of the volume section, the directory section and the reference parameter section from the image disk. If there exists, the controller unit 2
In response to the instruction to check whether or not the disk of the corresponding disk device is exchanged, it is checked whether or not the disk of the corresponding disk device is exchanged.

The means for detecting the disk exchange is realized, for example, in a disk device such as a magneto-optical disk or a CD-ROM, by issuing a unique command to the disk device, reading the status of the disk device, and judging by the contents. It Reference numeral 5 decompresses the compressed image data read by the decoder unit and writes the restored image into the image memory 6. If the read image data is uncompressed, it is directly written in the image memory 6 without going through the decoder unit 5.

A display unit 7 outputs the contents of the image memory to the monitor 10. FIG. 3 is a diagram showing the configurations of the cache buffer memory 3 and the cache buffer management table 4. The cache buffer management table 4 stores the addresses on the cache buffer memory 3 of the volume part, the directory part, and the reference parameter part for each disk device number. When the data of each part is not held in the cache buffer memory, the address of each part of the cache buffer management table 4 is 0.

Therefore, the controller 2 determines whether or not the data exists in the cache buffer memory depending on whether the address of each unit is 0 or not. FIG. 4 is a diagram showing the state of the cache buffer management table of the image file apparatus immediately after the power is turned on, and the addresses of all parts are 0.

The operation of the image reproduction / display command when this embodiment is used will be described below with reference to the flowchart of FIG.

In S1, the disk device N and the image number M are designated by the host computer 1, and the image reproduction display command is input. The controller unit 2 receives the image reproduction display command, and performs the operations after S2. In S2, the address of the directory portion corresponding to the disk device N in the cache buffer management table 3 is referred to. In S3, it is determined whether or not the directory portion of the disk device N exists on the cache buffer memory 3 depending on whether the address of the directory portion is 0 or not.

If the address is 0, it does not exist in the cache buffer memory 3, and in other cases, the directory portion exists at that address in the cache buffer memory 3. If the directory portion exists in S3, the disc exchange detecting means 11 checks in S4 whether or not the disc of the disc device N has been replaced. When the disk exchange is not detected in S4, the directory section on the cache buffer memory is referred to in S5, the Mth address is read from the start address, and the data start address on the disk of the image number M is obtained.

On the other hand, if the directory portion does not exist in the cache buffer memory 3 in S3, the address of the volume portion corresponding to the disk device N of the cache buffer management table 3 is referred to in S6, and the address of the volume portion is 0 in S7. Whether or not the volume portion of the disk device N exists on the cache buffer memory 3 is determined. If the address is 0, it does not exist in the cache buffer memory 3, and otherwise, the volume part exists at that address in the cache buffer memory 3.

If the volume portion exists in the determination in S7, the disc exchange detecting means 11 checks in S8 whether or not the disc of the disc device N has been replaced. When the disk exchange is not detected in S8, the volume section on the cache buffer memory is referred to in S9 to obtain the start address and size of the directory section on the corresponding disk, and in S10, the directory section is read from the disk of the disk device N. Is read to the cache buffer memory 3 and S11
And the disk device N of the cache buffer management table 4
The address of the directory part corresponding to is updated. After that, the process proceeds to S5.

If the volume portion does not exist in the cache buffer memory 3 in S7, the disk of the disk device N is accessed in S12, the volume portion is read out and held in the cache buffer memory 3, and S1
In 3 the address of the volume part corresponding to the disk device N in the cache buffer management table 4 is updated, after which the process proceeds to S9.

When the disk exchange is detected in S8, all the data of the disk device N existing in the cache buffer memory is discarded in S14, and the address of each part corresponding to the disk device N of the disk management table 4 is set. It is initialized to 0 and the process proceeds to S12. Similarly, when the disk exchange is detected in S4, all the data of the disk device N existing in the cache buffer memory is discarded in S15, and the address of each part corresponding to the disk device N of the disk management table 4 is set to 0. Initialize, S1
Proceed to step 2.

As described above, the directory portion is read from the cache buffer or the disc, the image data address of the designated number is obtained, the disc device N is accessed in S16, and the image data is first obtained from the obtained address. Read only the header information of the copy.

Next, in S17, it is determined from the header information whether the image data is compressed data or uncompressed data. If it is compressed data, the address of the reference parameter portion corresponding to the disk device N of the cache buffer management table 3 is referred to in S18, and the disk is stored in the cache buffer memory 3 depending on whether the address of the reference parameter portion is 0 in S19. It is determined whether the reference parameter part of the device N exists. If it exists, it is checked in S20 whether the disk of the disk device N has been replaced. If the disk exchange is not detected in S20, the decoder unit 5 reads out the reference parameter portion of the disk device N existing on the cache buffer memory and decompresses the parameter in S23.
Set to.

Next, in S24, the disk of the disk device N is accessed, the main body of the image data is read, the expanded image data is written in the image memory 6 via the decoder unit, and in S25 via the display unit 7. , The contents of the image memory 6 are displayed, and the command processing ends.

On the other hand, if the image data M to be read in S17 is uncompressed, the main body of the image data is directly read into the image memory 6 without passing through the decoder section in S26, and the process proceeds to S25. When the disk exchange is detected in S20, it means that the disk exchange has occurred during the command processing. S2
At 7, all the data of the disk device N on the cache buffer memory 3 is discarded, and the address of each part corresponding to the disk device N of the disk management table 4 is initialized to 0.

Next, the disk device N is accessed in S28, the reference parameter part is read out, the reference parameter part is held in the cache buffer in S29, and the address of the reference parameter part of the disk device N in the cache buffer management table 3 is updated. To do. After that, in S30, the host computer is notified that the disk has been replaced during the command processing, and the host computer performs error processing such as displaying an error and interrupts the processing.

As described above, in the command that needs to refer to the volume part, directory part, and reference parameter part of the disk, the data of each part is read from the cache buffer if it is in the cache buffer, and if it is not in the cache buffer, the disk is read. When the above command is issued to the same disk the next time, the necessary data for each part will be read quickly without accessing the disk by reading the data from the disk, holding it in the cache buffer, and managing its address using the management table. Can be referred to.

That is, in the above command, the disk is accessed and the data of each section is read out by the first command that requires each section after the power of the image file apparatus is turned on, and the disk apparatus in which the disk is replaced. On the other hand, only the first command that requires each part is issued, and the commands for the same disk from the next time onward can refer to the data in the cache buffer, so that the command processing can be speeded up.

Further, when referring to the data in the cache buffer, the data in the cache buffer must be checked by the disk device in order to confirm that the data in the image disk is currently loaded in the disk device. On the other hand, it is checked whether or not the disk has been replaced, and if it is detected that the disk has been replaced, all the data in the cache buffer held by the disk unit number is discarded, and it is necessary from the disk newly installed in the disk unit. The data of each part is read and the cache buffer is updated.

As a result, the user who issues the command can correctly read the currently mounted disc without being aware of disc replacement.

In the second embodiment of the invention, when the power of the image filing apparatus in FIG. 1 is turned on, the programs installed in the controller section 2 cause the connected disk apparatuses 81 to 8n to be connected. The volume part, the directory part, and the reference parameter part of each disk are all read and held in the cache buffer memory 3, and the head address of each part on the cache buffer memory 3 is written in the cache buffer management table 4.
That is, since the data of all the respective parts of the disk, which are mounted when the power is turned on, exist in the cache memory,
High-speed processing is possible from the first command.

[0040]

As described in detail above, according to the first and second aspects of the present invention, by holding in the cache buffer the necessary data commonly used by the commands to access the disk, the image data Playback display of other commands to access the disc. Disk access can be efficiently minimized and commands for accessing the disk can be processed at high speed. Further, it is possible to provide an image filing device in which a user can issue a read command or a disc access command without being aware of disc exchange.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an image filing device according to an embodiment of the invention of claims 1 and 2 of the present application.

FIG. 2 is a schematic diagram of a logical format of an image disc used in an image filing apparatus according to the present invention.

FIG. 3 is a schematic diagram of a cache buffer memory and a cache buffer management table of the image file device according to the present invention.

4 is a schematic diagram showing an initial state of a cache buffer management table according to FIG.

FIG. 5 is a flowchart showing a flow of a control procedure of an image reproduction display command using the same embodiment.

[Explanation of Codes] 1 host computer 2 controller section 3 cache buffer memory 4 cache buffer management table 5 decoder section 6 image memory 7 display section 10 monitor 11 disk replacement detection means 81-8n disk device 91-9n image disk

Claims (2)

[Claims] 1. An image file comprising a plurality of disc devices to which a plurality of discs can be attached and detached, and a host computer, wherein image data of a designated disc is read, decoded, reproduced and displayed according to an instruction from the host computer. In the device, a cache buffer memory that holds a volume part, a directory part, and a reference parameter part of a disk necessary for reading image data for each disk, and a cache buffer management table that manages addresses on the cache buffer memory of each part that is held When,
When the host computer issues a command for reading and reproducing and displaying an image from the disc or a command for reading out any of the volume portion, directory portion, and reference parameter portion of the disc, which has disc exchange detection means in the disc device. If the necessary data of each part corresponding to the designated disk does not exist in the cache buffer memory by referring to the management table, the designated disk is accessed, the necessary parts are read into the cache buffer memory, and the management table is stored. If the necessary parts are present in the cache buffer memory, the presence / absence of disk replacement in the disk device is detected, and if there is no replacement, the corresponding data in the necessary parts in the cache buffer memory is read out. , A disk swap was detected The image file device characterized by discarding all data on the cache buffer memory of the disk, accessing the disk, newly reading the necessary parts into the cache buffer memory, and updating the management table. . 2. A volume section, a directory section, and a reference parameter section of all the disks mounted in the disk device when the power is turned on are read, held in the cache buffer memory for each disk, and the management table is validated. The image file device according to claim 1, wherein