JPH11205755A - Data storage managing method in video server - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a data managing method for fast reproduction capable of reducing a data reading time at the time of fast reproduction and reducing the memory size of a necessary buffer memory. SOLUTION: A video server 10 is constituted of a data storage device 20 constituted of plural disk-like storage medium, an input/output device 40 connected to an external data storage device 70 and external terminals 90, 91, 92..., a buffer memory 30 storing input/output data, a disk-like storage medium/ buffer data managing part 60 managing the data storage arrangement and the data transfer of the device 20 and a microprocessor 50 controlling the device 20, the memory 30 and the device 40. Then, video data for fast reproduction is recorded in the device 20 to be consecutively arranged and video data is fast read to the memory 30 from the device 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a data storage management method in a video server.

[0002]

2. Description of the Related Art FIG. 3 shows a conventional data storage management method in a video server.

FIG. 4 is a block diagram of a data management apparatus showing a video server. In FIG. 4, reference numeral 10 denotes an entire video server, and 90 to 92 are terminal devices for receiving video data output from the video server. Reference numeral 20 denotes a data storage device that stores video data. Reference numeral 30 denotes a buffer memory for inputting and outputting data from the data storage device 20.

[0004] Reference numeral 40 denotes an input terminal for storing video data from an external data storage device 70 such as a video tape, and a terminal device for reading the video data stored in the buffer memory 30.
It is an input / output device for outputting to 90-92.

Reference numeral 60 denotes a data storage device 20 and a buffer memory 30.
The microprocessor 50 is a data storage device / buffer memory management unit having management information of
Video data is input and output between the data storage device 20 and the buffer memory 30 based on the information of the buffer memory management unit 60.

FIG. 3 shows a case where video data is handled as a file divided into blocks of a fixed size, and blocks are sequentially stored in each of hard disks 201 to 204 of a data storage device 20 composed of four hard disks. The state is shown.

In such a data storage method, when the video server performs high-speed reproduction, for example, at double-speed reproduction, the hard disk 201 and the blocks 0, 4, 8,.
.. Are read from the buffer memory 30 into the buffer memory 30, and the data is output from the buffer memory 30 to the terminals 90 to 92 through the input / output device 40 in the order of double speed reproduction. When the video data is distributed and stored in a plurality of hard disks in this way, by reading necessary blocks from each hard disk in parallel, a read speed similar to that of normal reproduction can be satisfied.

However, at the time of 8 × speed reproduction, a specific disc 2
Skip the odd-numbered blocks of video data from 01,
Only the even blocks need to be read. Generally, the data transfer speed of the hard disk is higher in a continuous area and as the data size to be transferred is larger. That is, in the case of high-speed reproduction, the data area to be read becomes discontinuous,
Extra time is required for the read head of the hard disk to move to the desired data storage location, thus reducing the overall read speed.

Therefore, there is a method of improving the reading speed by reading a plurality of blocks at once instead of reading only one block at a time. However, in such a method, for example, when reading four blocks at a time, the required data is only two blocks at 8 × speed and only one block at 16 × speed, and the buffer memory size is required to store unnecessary data. Has a problem that the size becomes larger.

[0010]

As described above, the conventional video server has a problem that the data read speed at the time of high-speed reproduction is reduced or the buffer memory size is increased.

SUMMARY OF THE INVENTION In view of the foregoing, it is an object of the present invention to provide a high-speed reproduction data management method that reduces the data read time during high-speed reproduction and reduces the required buffer memory size.

[0012]

According to a first aspect of the present invention, there is provided a data management method for a video server, comprising: a data storage device comprising a plurality of disk-shaped recording media; A buffer memory for storing video data input to and output from the data storage device; an input / output device for inputting video data from an external data storage device storing video data and outputting the video data to the outside; A data storage device / buffer memory management unit for managing the arrangement of video data of the device and data transfer between the data storage device and the buffer memory;
In a video server comprising a microprocessor for controlling the data storage device, the buffer memory and the input / output device based on the information of the data storage device / buffer memory management unit, video data for high-speed reproduction is continuously arranged. Recorded in the data storage device as follows,
The video data is read from the data storage device to the buffer memory at a high speed in accordance with the reproduction speed.

According to a second aspect of the present invention, there is provided a data management method in a video server according to the second aspect of the present invention, in which data reading from a data storage device is switched for each disk-shaped recording medium group so that a reading load can be distributed. It is.

According to a third aspect of the present invention, there is provided a data management method for a video server according to the third aspect of the present invention, in which data read from a data storage device is managed in file units in order to distribute a read load.

According to a fourth aspect of the present invention, there is provided a data management method for a video server according to a fourth aspect of the present invention, wherein a unit of reading data from a data storage device is made variable in order to make a speed range of high-speed reproduction variable. It is.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) FIGS. 1 and 2 are diagrams showing an embodiment utilizing a data management method in a video server according to the first invention of the present application.

The following description focuses on the operation when the video server 10 performs high-speed playback. The input of the video data to the data storage device 20 is such that the input / output device 40 controlled by the microprocessor 50 reads the video data stored in the external data storage device 70 such as a video tape in block units, and transfers the video data to the buffer memory 30. This is done by writing.

Here, when each block is sequentially allocated to and stored in four hard disks constituting the data storage device 20, a block for high-speed reproduction which is a multiple of 4 (4/8/16,...) Are stored in the hard disk 301. If each block (0,4,8,12,16, ..) is arranged in a continuous area of the hard disk, the data for 8x speed (0,8,16, ..)
16x speed data (0,16, ..) is arranged discontinuously.

Generally, the data transfer time and effective data transfer speed of a hard disk are expressed by the following equations, respectively.

[0020]

(Equation 1)

[0021]

(Equation 2)

Although the moving time between blocks cannot be avoided in the discontinuous arrangement of a plurality of blocks, the reading time is shortened between a plurality of blocks arranged in a continuous area since the time can be ignored. That is, the effective data transfer speed is improved.

Therefore, a block group is composed of a fixed number of blocks, and the data storage device / buffer memory management unit 60 performs high-speed reproduction so that high-speed reproduction data (8 × speed / 16 × speed) is arranged continuously. A data storage device allocation table 80 for use. Based on the high-speed reproduction data storage device assignment table 80, the microprocessor 50 transfers data from the buffer memory 30 to the hard disk 301 in block group units and stores the data in a continuous area. Data is stored in other hard disks in the same arrangement.

When the video data is stored and arranged as described above, when the microprocessor 50 reads video data from the data storage device 20 to the buffer memory 30, the data storage device for high-speed reproduction is passed through the data storage device / buffer memory management unit 60. Based on the information obtained from the assignment table 80, only necessary data can be collectively read in units of 4 blocks at 8 × speed and in 2 blocks at 16 × speed. That is, since the read block size increases, the data transfer speed improves.

The input / output device 40 under the control of the microprocessor 50 reads the high-speed reproduction block data from the buffer 30 according to the reproduction order, and outputs the data to the terminal requesting the high-speed reproduction of the video data.

On the other hand, in the case of normal reproduction, since it is sufficient to read data from each hard disk in units of four consecutive blocks, there is no reduction in the reading speed due to discontinuity.

As described above, according to the present embodiment, the data storage device 20 for high-speed reproduction data is stored in the buffer memory.
It is possible to increase the read speed to 30. In addition, since only a desired plurality of block data is read at a time, the buffer memory size required for reading can be reduced.

(Embodiment 2) FIGS. 5 and 6 show an embodiment of a data management method in a video server according to the second invention of the present application.

According to a second aspect of the present invention, there is provided a data storage management method according to the first aspect of the present invention, wherein the video data storage arrangement of the data storage device on the disk-shaped recording medium is sequentially switched in block group units.

As shown in FIG. 5, when video data for high-speed reproduction is limitedly stored in the specific hard disk 301,
When high-speed playback requests are concentrated on the same file from a plurality of terminals, the time for reading video data from the data storage device 20 to the buffer memory 30 may be delayed.

Therefore, as shown in FIG. 6, the assignment of each hard disk is switched for every file in block units, and video data for high-speed reproduction is distributed and stored in each of the hard disks 401 to 404. The video data storage arrangement information of the hard disk in FIGS. 5 and 6 is stored in the data storage device / buffer memory management unit 60. As a result, since the data is read from all the hard disks, that is, the entire data storage device, to the buffer memory, it is possible to prevent a reduction in the reading speed.

(Embodiment 3) FIG. 7 shows a third embodiment of the present invention.
FIG. 13 is a diagram showing an embodiment of a data management method in the video server according to the third invention of the present application described in FIG.

According to a third aspect of the present invention, there is provided a data storage management method according to the first aspect of the present invention, wherein the video data storage arrangement of the data storage device on the disk-shaped recording medium is switched in file units.

As described in the second embodiment,
The read speed may be reduced due to the centralized storage of high-speed playback video data on a specific hard disk. Therefore, first, as shown in FIG. 7A, the storage arrangement of the video data for high-speed reproduction on the hard disk is classified into an arrangement format for centrally storing the video data for each hard disk. The type of arrangement is the number of hard disks (4 in this case).

Next, as shown in FIG. 7 (b), the file 1 is stored in the hard disk 401 in a centralized storage type 410.
Is repeated for each block group.

An arrangement type 402 for centrally storing the file 2 on the hard disk 402, and a file 3 for the hard disk 402.
Placement type 430 for central storage in 403, file 4 for placement type 440 for central storage in hard disk 404, file 5
Is an arrangement type 410. Hereinafter, this assignment is repeated for each file. By dispersing and storing the high-speed playback video data on a file-by-file basis in each of the hard disks 401 to 404, the read speed from the data storage device to the buffer memory decreases in response to a high-speed playback request from a plurality of terminals for a plurality of files. It became possible to prevent.

(Embodiment 4) FIG. 8 is a diagram showing an embodiment of a data management method in a video server according to the fourth invention of the present application.

According to a fourth aspect of the present invention, there is provided a data storage management method according to the first aspect of the present invention, wherein the readout size is made variable.

FIG. 8 shows a data arrangement of a hard disk in which high-speed reproduction data is stored.

In FIG. 1 showing the first embodiment of the present invention, only block data of 8 × speed reproduction and 16 × speed reproduction are continuous, and for example, block data of 12 × speed reproduction are discontinuous. Was. In this manner, the types of high-speed reproduction that are continuously arranged may be limited.

Therefore, by combining a plurality of small block groups having different arrangements, the arrangement is configured to increase the types of continuous high-speed reproduction block data.
In FIG. 8, small block groups 600 to
The large block group 700 is configured using six 605s so that each block data of 8/12/16 speed reproduction is continuous, and thereafter, the same arrangement is repeated with the large block group as one unit.

This makes it possible to make the speed range of the high-speed reproduction continuously arranged variable and to change the size of the read buffer.

Although the embodiment of the present invention has been described using a hard disk, the present invention can be applied to a disk-shaped recording medium such as a magneto-optical disk. Further, the data continuously arranged in the present invention is not limited to the block data for high-speed reproduction, and can be applied to a special reproduction such as reverse reproduction or a case of improving the reading speed for a specific type of data.

[0044]

As described above, according to the present invention, a data storage device / buffer memory management unit for continuously arranging video data for high-speed reproduction in a data storage device is constructed so that a buffer from a data storage device can be obtained. It has become possible to improve the reading speed to the memory.

Further, since data reading from the data storage device is switched for each disk-shaped recording medium group and collectively read, the buffer memory size required for reading can be reduced, and the load of reading can be reduced by dispersing the reading load. Was.

Similarly, in order to manage data reading from the data storage device on a file basis and perform batch reading,
The buffer memory size required for reading can be reduced, and the load can be reduced by dispersing the reading load.

Further, since the unit of reading data from the data storage device is made variable, it becomes possible to make the speed range of high-speed reproduction variable and to make the buffer memory size variable.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a data storage management method in a video server according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a high-speed playback data management device in the video server of the present invention.

FIG. 3 is a block diagram showing a data storage management method in a conventional video server.

FIG. 4 is a block diagram of a data management device in a conventional video server.

FIG. 5 is a block diagram showing a data storage management method according to the first embodiment of the present invention.

FIG. 6 is a block diagram illustrating a data storage management method according to a second embodiment of the present invention.

FIG. 7 is a block diagram illustrating a data storage management method according to a third embodiment of the present invention.

FIG. 8 is a block diagram showing a data storage management method according to a fourth embodiment of the present invention.

[Description of sign]

 10 Video server 20 Data storage device 30 Buffer memory 40 Input / output device 50 Microprocessor 60 Data storage device / buffer memory management unit 70 External data storage device 80 Data storage device allocation table for high-speed playback 90 Terminal 1 91 Terminal 2 92 Terminal 3 100 ~ 104 File 201 ~ 204 Hard Disk 301 ~ 304 Hard Disk 401 ~ 404 Hard Disk 410 ~ 440 Data Allocation Type 1-4 501 ~ 504 Hard Disk 600 ~ 605 Small block group of video data 700 Large block group of video data

Claims (4)

[Claims] 1. A data storage device comprising a plurality of disk-shaped recording media; a buffer memory for storing video data input / output to / from the data storage device; and an external data storage device for storing video data. An input / output device for inputting and outputting video data from an external device, a data storage device / buffer memory management unit for managing the arrangement of video data in the data storage device and data transfer between the data storage device and the buffer memory A video server comprising a microprocessor for controlling the data storage device, the buffer memory, and the input / output device based on information of the data storage device / buffer memory management unit, wherein video data for high-speed reproduction is continuously arranged; Recorded in the data storage device so that the data Data storage management method characterized in that from the storage device of video data at high speed into the buffer memory. 2. The data storage management method according to claim 1, wherein the data arrangement of the data storage device is switched for each disk-shaped recording medium group. 3. The data storage management method according to claim 1, wherein the data arrangement of the data storage device is managed in file units. 4. The data storage management method according to claim 1, wherein a speed range of the high-speed reproduction is made variable.