JP3056000B2 - Multimedia data network transfer method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multimedia data network transfer system for managing or transferring multimedia data accessed in a time series between a plurality of computers distributed and connected on a network.

[0002]

2. Description of the Related Art Local area networks (LANs)
In a computer system of a distributed processing system in which a plurality of host computers and terminals are connected to a network such as a computer and the processing is performed by distributing the host computers, various programs and databases can be used.
Also, even if one host computer on the network fails, another host computer can be used,
Resources can be shared and reliability can be improved.

In addition, with the recent trend toward computerized multimedia systems, operating systems are required to support multimedia functions. Further, multimedia processing of a network file system is also required for a computer system of a distributed processing system. At present, various network file systems (NFS, AFS, etc.) are provided.

In the conventional data transfer by this type of network file system, the transfer of time-critical data is not considered, and the entire file opened when the application is started is stored in the file.
The data is transferred as a cache to a local disk provided in each host computer.

Alternatively, a method has been used in which a file is divided into several blocks, and only the relevant blocks are transferred using a page fault caused by moving a file pointer.

[0006]

However, when handling multimedia data, the amount of data to be transferred for moving image data is enormous. When a file is opened, all data is stored in a local cache. In this case, it takes time to start an application that handles multimedia data.

Further, in the access using the page fault, a page fault occurs each time in an arbitrary block unit, so that a process for searching for a block corresponding to the page in which the page fault occurred must be performed each time. .

Therefore, as time passes,
There is also a problem that it is necessary to wait until a page fault occurs even for time-series data that is premised on sequential access.

[0009] In addition, when a file is fetched into the local cache by opening, the transfer time increases as the size of the fetched file increases, and it takes time to start up the application.

SUMMARY OF THE INVENTION An object of the present invention is to deal with time-series data by reducing the data transfer time, managing a large amount of multimedia data in a distributed processing environment, sharing multimedia data on a network, and using disk resources efficiently. It is to provide a multimedia data network transfer method that can be used.

[0011]

The present invention has the structure shown in FIG. 1 in order to solve the above problems and achieve the object. The present invention relates to a multimedia data network transfer system for managing or transferring multimedia data accessed in time series among a plurality of computers 2 distributed and connected on a network 1.
Is a network control unit 6 for controlling an agreement for data transfer on the network 1, a time measuring unit 3 for measuring time, a storage device 7 having a plurality of files 8 storing data, and a data The multimedia data control unit 5 controls a transfer block length of data to be transferred from the storage device 7 to the network control unit 6 and a transfer time interval of the data according to the format.

When a specific file among the files 8 is requested, the multimedia data control unit 5 determines which storage device 7 this specific file exists in, and according to the data format of the specific file. The transfer time interval is output to the time measuring unit 3, which measures time based on the transfer time interval, and transfers data from a specific file in the storage device 7 at each transfer time interval in units of transfer block length. To instruct the multimedia data control unit 5 to transfer the data to the network control unit 6.

More preferably, the following is desirable. That is, the storage device 7 has a file management table 9 for managing the file 8, and this file management table 9 has at least a transfer block length and a transfer time interval, and which storage device 7 owns the multimedia data. Link information indicating whether or not there is a

Each computer 2 has a network control unit 6 for controlling an agreement for data transfer on the network 1, a time measuring unit 3 for measuring time, and a storage device having a plurality of files 8 for storing data. Device 7,
A multimedia data control unit 5 for transferring data from the storage device 7 to the network control unit 6 based on a transfer block length and a transfer time interval designated by a user is provided.

When a specific file among the files 8 is requested, the multimedia data control unit 5 determines which storage device 7 this specific file exists in, and determines the transfer time specified by the user. The interval is output to the time measuring unit 3, which measures the time based on the transfer time interval specified by the user and transfers data from a specific file in the storage device 7 at each transfer time interval. The multimedia data control unit 5 is instructed to transfer the data to the network control unit 6 in block length units.

[0016]

According to the present invention, when a request for a specific file is made to the multimedia data control unit 5, the multimedia data control unit 5 determines which storage device 7 the specific file exists. Then, a transfer time interval corresponding to the data format of the specific file is output to the time measuring unit 3,
The time measuring unit 3 measures the time based on the transfer time interval, and controls the multimedia data to transfer data from a specific file in the storage device 7 to the network control unit 6 in units of transfer block length at each transfer time interval. Since the instruction is given to the unit 5, the multimedia data can be transferred to the multimedia data control unit 5 on the application side with a transfer block length and a transfer time interval specified in advance. Therefore, the transfer time can be reduced, and a large amount of multimedia data can be managed in a distributed processing environment. Therefore, multimedia data can be shared on a network, and disk resources can be effectively used.

Further, data transfer may be managed using at least the transfer block length, transfer time interval, and link information stored in the file management table. The same effect as described above can also be obtained by designating the transfer block length and the transfer time interval by the user.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described.
FIG. 2 is a block diagram showing a configuration of an embodiment of the present invention, FIG. 3 is a flowchart of a data transfer method in the embodiment, and FIG. 4 is a diagram showing a configuration of a file management table.

Regarding access to the time-series data, the next access time, the position of the file, and the like can be predicted from the attributes of the file, such as the data update cycle and the block unit.

The LAN 1 is connected to a host computer 2-1 as an application and a host computer 2-2 as a file server. Here, the host computer 2-1 is described as an application, but may be used as a file server.

The host computers 2-1 and 2-2 are configured as follows. The program 10 included in the host computer 2-1 is one of a plurality of user processes, and is a user program requesting reproduction of multimedia data.

The allocate area 20 is an area which is requested from the program 10 and is temporally allocated (allocated). Timers 3-1 and 3-2 are allocated area 2
0 is temporally managed.

The area management unit 4 manages a user's physical memory over time. Discs 7-1 and 7-2
Has a file for storing data and a file management table for managing this file.

The multimedia data control unit 5-1 receives a request for opening or reading a file from the program 10, and stores the requested file in the disk 7 of any of the host computers 2-1 and 2-2 on the network 1. 1, 7-2, and determines, according to the format of the requested data, the data to be transferred from the disk (7-2) in which the requested data exists to the network control unit (6-2). The amount and timing are controlled, that is, it is determined whether processing is possible (accessible) in a mode for handling time-series data (a mode for automatically transferring an arbitrary data size as time passes).

If the multimedia data control unit 5-1 can process in a mode that handles time-series data, the multimedia data control unit 5-1 of the host computer 2-1 owning the requested file on the network 1 sends it to the multimedia data control unit 5-2. Request transfer of time series data.

The network control units 6-1 and 6-2 control a data transfer protocol of the network 1. The timer 3-2 measures the time according to the timing calculated by the multimedia data control unit 5-1. After the timing measurement, the timer 3-2 transfers the data requested from the disk 7-2 to the network control unit 6-2. An instruction is given to the media data control unit 5-2.

The file management table shown in FIG.
D information, NFS flag set, access right, time series data, data block length size, update period, and link information are stored.

Next, a data transfer method according to the first embodiment will be described with reference to FIGS. The user application requests the multimedia data control unit 5-1 to open the multimedia data file (step 100 in FIG. 3).

In the multimedia data control unit 5-1,
It is determined whether the requested file is on the disk 7-1 of the host computer 2-1 or on the disk 7-2 of another host computer 2-2 on the network 1 (step 101).

Then, the program 10 requests the area management unit 4-1 to allocate a time area for data processing. If it is determined that the target file is in a directory linked to another host computer during the directory search of the target file, an open request is sent to the multimedia data via the network control units 6-1, 6-1. Output to the control unit 5-2 (Step 10
2).

Upon receiving the open request, the multimedia data control unit 5-2 confirms the requested file and determines whether the file exists and is accessible in terms of data amount and timing (step 103).

If access is possible, success result information (this result information includes file permission information,
If the data is time-series data or time-series data, a unit block length and an update cycle are included. ) Is returned to the multimedia data control unit 5-1 (step 104).

When the multimedia data control unit 5-1 receives the result, if it is accessible, the multimedia data control unit 5-1 stores a flag of a network file system (NFS) as a file attribute and link information for associating disks.
The opened file is set in the file management table for managing the file (step 105). Then, the ID (personal information) of the file management table in which the information is set is returned to the user.

[0034] The user can then, based on the ID,
A read request is issued for the opened multimedia data file using the read. This request is sent to the multimedia data control unit 5-2 that owns the file via the network control units 6-1 and 6-2 (step 106).

In the multimedia data control unit 5-2,
After transferring the first block based on the information in the file header (step 107), the transfer block length and the data transfer time interval are registered in the timer 3-2 from the information on the file head (step 108). Timer 3-2
When the registered time arrives, it notifies the multimedia data control unit 5-2. Upon receiving the notification, the multimedia data control unit 5-2 reads the requested data from the disk 7-2 and reads the requested data from the disk 7-2.
(Step 109).

In accordance with the data format specified in this manner, the multimedia data control unit 5-2 has a block length of 600K as shown in FIG. 4 based on the information of the file header of the file management table. In addition, since the data is transferred to the multimedia data control unit 5-1 at an update period of 30 ms based on the timer 3-2, a large amount of multimedia data can be managed in a distributed environment, so that the multimedia data can be shared on the network 1. The disk resources can be used effectively.

The present invention is not limited to the embodiment described above. (1) In the embodiment, the data transfer is controlled based on the information (block length, update cycle, etc.) written in the file header. For example, when the user requests read, the block length, update cycle, etc. May be changed.

[0038] In this way, it is possible to perform reproduction at a changed speed. (2) In the embodiment or the example of (1), the allocation area 20 is updated at the data transfer timing of the multimedia data control unit 5-2. 1
May be performed based on the notification of the timer 3-1.

In this case, the same effect as that of the embodiment can be obtained. (3) Further, in the embodiment or the example of (2), the computer 2-2 on the file server side transfers data at a proper timing, but the timer 3-1 periodically sets the pseudo page. A fault may be generated so that data of a page to be accessed next by the application is obtained from the network. Even in this case, the same effect as that of the embodiment can be obtained.

[0040]

According to the present invention, since a large amount of multimedia data can be managed in a distributed processing environment, multimedia data can be shared on a network, disk resources can be effectively used, and multimedia can be used in a distributed processing environment. It has a great effect.

[Brief description of the drawings]

FIG. 1 is a principle diagram of the present invention.

FIG. 2 is a configuration block diagram of an embodiment of the present invention.

FIG. 3 is a flowchart of a multimedia data transfer method according to the embodiment.

FIG. 4 is a diagram showing a configuration of a file management table.

[Explanation of symbols]

 1. LAN 2-1 2-2 Host computer 3-1 2-2 Timer 4-1 Area management unit 5-1 5-2 Multimedia data control unit 6-1 , 6-2 .. Network control unit 7-1, 7-2. Disk 10. Program 20. Allocate area

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-85654 (JP, A) JP-A-5-14763 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G06F 13/00 G06T 1/00 H04N 7/173 H04L 12 / 54,12 / 58

Claims (3)

(57) [Claims] 1. A multimedia data network transfer system for managing or transferring multimedia data accessed in time series among a plurality of computers (2) dispersedly connected on a network (1), Each computer (2) is connected to the network (1)
A network control unit (6) for controlling the above data transfer agreement and a time measurement unit (3) for measuring time
And a storage device (7) having a plurality of files (8) storing data, and transferring the data from the storage device (7) to the network control unit (6) according to the data format of the file (8). A multimedia data control unit (5) for controlling a transfer block length of data to be transferred and a transfer time interval of the data, wherein the multimedia data control unit (5) is a specific file among the files (8) Is requested, it is determined which storage device (7) this specific file exists in, and the transfer time interval according to the data format of the specific file is sent to the time measuring unit (3). The time measurement unit (3) measures time based on the transfer time interval, and transfers data from a specific file in the storage device (7) at each transfer time interval to the transfer block. Multimedia data network transfer method, characterized by instructing the multimedia data control unit (5) to transfer the network controller using the clock length units (6). 2. The storage device (7) has a file management table (9) for managing the file (8). The file management table (9) includes at least the transfer block length and the transfer time. 2. The multimedia data network transfer system according to claim 1, wherein link information indicating an interval and which storage device (7) owns the multimedia data is stored. 3. A multimedia data network transfer system for managing or transferring time-series accessed multimedia data among a plurality of computers (2) distributed and connected on a network (1), Each computer (2) is connected to the network (1)
A network control unit (6) for controlling the above data transfer agreement and a time measurement unit (3) for measuring time
A storage device (7) having a plurality of files (8) storing data, and the network control unit (6) from the storage device (7) based on a transfer block length and a transfer time interval designated by a user. And a multimedia data control unit (5) for transferring data to the specific file when the specific file is requested from the file (8). Is determined in which of the storage devices (7), the transfer time interval specified by the user is output to the time measuring unit (3), and the time measuring unit (3) A time is measured based on a transfer time interval designated by a user, and data is transferred from a specific file in the storage device (7) in units of the transfer block length at each transfer time interval. Multimedia data network transfer method, characterized by instructing the multimedia data control unit (5) to forward to the network control unit (6).