JP2000092471A - Video server device and its band managing method, and recording medium where band managing program is recorded - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dynamically change the band management according to the state of a load and to easily exhibit its maximum capability. SOLUTION: This device is equipped with a command input/output part 108 which inputs a command from a terminal, a video data storage part 106 which stores video data, a video data input/output part 107 which inputs and outputs the video data, and a disk control part 105 which controls the video data storage part 106. The band for transferring the video data is managed between the video data storage part 106 and video data input/output part 107. When the command is received from the terminal, a band to be assigned to the terminal is determined according to the kind of the received command and usable bands which are managed and currently usable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video server apparatus which is connected to at least one terminal and inputs / outputs digital data including video data and audio data in response to a command (request) from the terminal, and a bandwidth management thereof. The present invention relates to a method and a recording medium recording a band management program.

[0002]

2. Description of the Related Art A video server device stores, for example, video data constituting a movie title and sends out video data requested by a plurality of terminals connected by communication lines. In recent years, in video server apparatuses, those using a hard disk as recording media have become mainstream. As is well known, the maximum capacity of a video server device using a hard disk is defined by the read / write performance of the hard disk itself and the band (transfer speed) of the internal bus. Further, in such a video server device, the read and write performance may be degraded due to the seek operation of the head or the like, that is, the read and write performance may fluctuate. The conventional video server device has a configuration in which a buffer is provided for each of a plurality of terminals to absorb the above-described fluctuation and to prevent a delay in input / output (transfer) processing of video data. Further, in a conventional video server device, when a terminal is connected using a communication line, a band of video data is fixedly allocated to the terminal. Thus, the conventional video server device individually manages the transfer processing of the video data to each terminal.

[0003]

In the conventional video server apparatus as described above, a band of video data is fixedly allocated to each terminal. For this reason, the conventional video server device cannot dynamically cope with a data transfer request (load) from each terminal, and cannot fully utilize the capability of the video server device. A problem arose. Further, the conventional video server device and each of the plurality of terminals are connected via a buffer in order to absorb the above-mentioned fluctuation. For this reason, in the conventional video server device, it is necessary to first input and output video data to and from the buffer, and it takes time to transfer the video data. More specifically, a conventional video server device is, for example, one.
After receiving a cue-up (hereinafter referred to as “cue-up”) command for a video data file to be played back from one terminal until a terminal starts playing back the video data specified by the cue-up command, a predetermined amount It is necessary to fill the buffer with the video data and output the video data sequentially, which requires a great deal of time for the video data transfer process. Further, in the conventional video server device, the video data requested by the cue-up command is output to the one terminal without grasping the transfer process of the video data to another terminal. For this reason, in the conventional video server device, even when the video data reading and transfer capabilities have a margin, the video data transfer process is performed within the band allocated to the terminal in advance. Further, the conventional video server apparatus is configured to perform the video data transfer processing in real time without discriminating between real-time data transfer and non-real-time data transfer.
For this reason, in the conventional video server device, when it is not necessary to perform the transfer processing in real time, for example, even when outputting the video data in file units, the transfer processing is performed in real time, causing an unnecessary increase in load.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and it is possible to dynamically change the bandwidth management according to the load situation, thereby easily exhibiting the maximum capacity. It is an object of the present invention to provide a video server device, a bandwidth management method thereof, and a recording medium on which a bandwidth management program is recorded.

[0005]

A video server device according to the present invention is a video server device connected to at least one terminal and for inputting and outputting digital data including video data in response to a command from the terminal. A command input / output unit for inputting a command from the terminal, a video data storage unit for holding video data, a video data input / output unit for inputting / outputting the video data, and a disk control unit for controlling the video data storage unit And manages a band for transferring video data between the video data storage unit and the video data input / output unit, and when a command is received from the terminal, manages the type of the received command. The band to be allocated to the terminal is determined based on the currently available band. With this configuration,
Bandwidth management can be dynamically changed according to the load situation of the video server device, and the maximum capability of the video server device can be easily exhibited.

A video server device according to another aspect of the present invention is a video server device connected to at least one terminal and inputting / outputting digital data including video data in response to a command from the terminal. A command input / output unit that inputs a command from a terminal, a video data storage unit that holds video data, a video data input / output unit that inputs and outputs the video data, and a disk control unit that controls the video data storage unit, Manages a band for transferring video data between the video data storage unit and the video data input / output unit, and when a plurality of commands are received, a command type, a preset command priority, and management. The bandwidth to be allocated to the terminal is determined based on the currently available bandwidth. With this configuration, it is possible to dynamically change the bandwidth management according to the load status of the video server device, and to perform data transfer processing that requires real-time performance rather than non-real-time data transfer processing. Bandwidth can be preferentially allocated.

A video server device according to another aspect of the invention is a video server device connected to at least one terminal and inputting / outputting digital data including video data in response to a command from the terminal. A command input / output unit that inputs a command from a terminal, a video data storage unit that holds video data, a video data input / output unit that inputs and outputs the video data, and a disk control unit that controls the video data storage unit, Manages a band for transferring video data between the video data storage unit and the video data input / output unit, and when a command is received from a plurality of terminals, a command type, a preset terminal priority order,
The bandwidth to be allocated to the terminal is determined based on the currently available bandwidth being managed. With this configuration, it is possible to dynamically change the bandwidth management according to the load situation of the video server device, and to preferentially process a command issued by a terminal with a higher priority. Become.

A video server device according to another aspect of the invention is a video server device connected to at least one terminal and inputting / outputting digital data including video data in response to a command from the terminal. A command input / output unit that inputs a command from a terminal, a video data storage unit that holds video data, a video data input / output unit that inputs and outputs the video data, and a disk control unit that controls the video data storage unit, Manages a band for transferring video data between the video data storage unit and the video data input / output unit, and when a transfer request for the same video data from a plurality of terminals is received within a certain period, as one request At the same time, the same video data is reproduced and transferred. With this configuration, the bandwidth management can be dynamically changed according to the load status of the video server device, and by allocating one bandwidth, a plurality of terminals can request the same video data transfer processing. Can be processed, and the load on the video server device can be reduced.

A bandwidth management method for a video server device according to the present invention is connected to at least one terminal and inputs / outputs digital data including video data in response to a command from the terminal. A command input step of inputting a command from the terminal, a command interpreting step of interpreting the command input in the command input step, and a command interpreted in the command interpreting step, wherein the command If the command requires a predetermined band when transferring video data between the units, the command is allocated to the terminal based on the type of the interpreted command and the currently available band being managed. The method further includes a band determining step of determining a band. With this configuration, the bandwidth management can be dynamically changed according to the load status of the video server device, and the maximum capacity of the video server device can be easily exhibited.

According to another aspect of the present invention, there is provided a bandwidth management method for a video server device connected to at least one terminal for inputting / outputting digital data including video data in response to a command from the terminal. A bandwidth management method, comprising: a command input step of inputting a command from the terminal; a command interpretation step of interpreting the command input in the command input step; In the case of a band required command that requires a predetermined band when transferring video data between the data input / output units, the type of the interpreted command, the priority of a preset command, and the current Bandwidth determining step of determining a bandwidth to be allocated to a terminal based on the available bandwidth of It is provided. With this configuration, it is possible to dynamically change the bandwidth management according to the load status of the video server device, and to perform data transfer processing that requires real-time performance rather than non-real-time data transfer processing. Bandwidth can be preferentially allocated.

According to another aspect of the present invention, there is provided a bandwidth management method for a video server device connected to at least one terminal, and for inputting / outputting digital data including video data in response to a command from the terminal. A bandwidth management method, comprising: a command input step of inputting a command from the terminal; a command interpretation step of interpreting the command input in the command input step; In the case of a band required command that requires a predetermined band when transferring video data between the data input / output units, the type of the interpreted command, the preset priority of the terminal, and the current A bandwidth determining step of determining a bandwidth to be allocated to the terminal based on the available bandwidth of the terminal. To have. With this configuration, it is possible to dynamically change the bandwidth management according to the load situation of the video server device, and to preferentially process a command issued by a terminal with a higher priority. Become.

According to another aspect of the present invention, there is provided a video server apparatus bandwidth management method for a video server apparatus which is connected to at least one terminal and inputs / outputs digital data including video data in response to a command from the terminal. A bandwidth management method, comprising: a command inputting step of inputting a command from the terminal, a command interpreting step of interpreting the command input in the command inputting step, wherein the command interpreted in the command interpreting step is a video data storage unit and a video data If the command requires a certain bandwidth when transferring video data between the input / output unit, whether the same video data transfer request as the command required for the bandwidth is received from another terminal within a certain period of time And the transfer of the same video data as the bandwidth required command Request is received from another terminal within a certain period of time, a transfer step of reproducing the same video data and transferring the same video data by combining the bandwidth required command and the transfer request from the another terminal as one request. ing. With this configuration, the bandwidth management can be dynamically changed according to the load status of the video server device, and by allocating one bandwidth, a plurality of terminals can request the same video data transfer processing. Can be processed, and the load on the video server device can be reduced.

The recording medium on which the bandwidth management program of the present invention is recorded has a command input step of inputting a command from a terminal, a command interpretation step of interpreting the command input in the command input step, and a command interpretation step of the command interpretation step. If the command is a band-required command that requires a predetermined band when transferring video data between the video data storage unit and the video data input / output unit, the type of the interpreted command and the current usage being managed The method includes a band determining step of determining a band to be allocated to the terminal based on a possible band. With this configuration, the bandwidth management can be dynamically changed according to the load status of the video server device, and the maximum capacity of the video server device can be easily exhibited.

According to another aspect of the present invention, there is provided a recording medium recording a bandwidth management program according to the present invention, comprising: a command input step for inputting a command from a terminal; a command interpretation step for interpreting the command input in the command input step; If the command interpreted in the above is a band required command that requires a predetermined band when video data is transferred between the video data storage unit and the video data input / output unit, the type of the interpreted command, a preset command And a bandwidth determining step of determining a bandwidth to be allocated to the terminal based on the priority of the terminal and the currently available bandwidth managed by the terminal. With this configuration, it is possible to dynamically change the bandwidth management according to the load status of the video server device, and to perform data transfer processing that requires real-time performance rather than non-real-time data transfer processing. Bandwidth can be preferentially allocated.

According to another aspect of the present invention, there is provided a recording medium storing a bandwidth management program according to the invention, comprising: a command inputting step of inputting a command from a terminal; a command interpreting step of interpreting the command input in the command inputting step; If the command interpreted in the above is a bandwidth required command that requires a predetermined bandwidth when transferring video data between the video data storage unit and the video data input / output unit, the type of the interpreted command, a preset terminal And a bandwidth determining step of determining a bandwidth to be allocated to the terminal based on the priority of the terminal and the currently available bandwidth managed by the terminal. With this configuration, it is possible to dynamically change the bandwidth management according to the load situation of the video server device, and to preferentially process a command issued by a terminal with a higher priority. Become.

According to another aspect of the present invention, there is provided a recording medium storing a bandwidth management program according to the present invention, comprising: a command input step for inputting a command from a terminal; a command interpretation step for interpreting the command input in the command input step; If the interpreted command is a bandwidth-required command that requires a predetermined bandwidth when transferring video data between the video data storage unit and the video data input / output unit, the same video data transfer request as that bandwidth-required command is added. A determination step of determining whether or not the terminal has been received within a predetermined period from the terminal, and if the same video data transfer request as the band required command has been received from another terminal within a predetermined period, the band required command and the Transfers transfer requests from different terminals into one request and plays back the same video data And a transfer step of transferring Te. With this configuration, the bandwidth management can be dynamically changed according to the load status of the video server device, and by allocating one bandwidth, a plurality of terminals can request the same video data transfer processing. Can be processed, and the load on the video server device can be reduced.

[0017]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a preferred embodiment of a video server apparatus according to the present invention.

First Embodiment [Configuration of Video Server] FIG. 1 is a block diagram showing a hardware configuration of a video server according to a first embodiment of the present invention. As shown in FIG. 1, a video server device 1 according to the present embodiment includes an MPU (microprocessor unit) 101 for executing a program, a main memory 103 for storing the program, and an MPU using a bus 104.
A bus bridge unit 102 for connecting the main memory 101 to the main memory 103 is provided. Further, the video server device 1 of the present embodiment includes a disk control device 105 for controlling the disk 106, and a video data input / output device for inputting / outputting video data to / from a plurality of terminals (not shown). 107, and a command input / output device 108 for inputting a command Cmd from each terminal and outputting a response to the command Cmd. The MPU 101 is connected via a bus bridge unit 102 to a main memory 103 and a disk control device 105, a video data input / output device 107, and a command input / output device 108 on a bus 104. The MPU 101 performs a function as the video server device 1 by executing a program stored in the main storage 103. Specifically, MP
The U 101 always keeps track of the transfer speed (bandwidth) of the video data between the video data input / output device 107 and the disk control device 105 connected to the plurality of disks 106 serving as the video data storage unit, and uses the data at its maximum usage. Manages available bandwidth. With this, when the MPU 101 receives a command Cmd from one terminal, the type of the command Cmd,
It is possible to determine the bandwidth to be allocated to the terminal based on the managed maximum available bandwidth. As a result, in the video server device 1 of the present embodiment, the bandwidth management can be dynamically changed according to the load status (operation status) of the video server device 1, and the maximum capacity of the video server device 1 Can be easily exhibited.

The main memory 103 is constituted by a RAM or a similar recording medium, and stores a plurality of programs including a band management program. Disk control device 10
5 issues an access command to each disk 106 based on a read / write command from the MPU 101.
The disk 106 is constituted by a nonvolatile large-capacity storage device, and stores digital data including video data constituting a title of a movie, for example. When the video server device 1 operates, necessary programs are read from the disk 106 to the main storage 103 and held.
Note that specific examples of video data include DV format and MP format.
Compression-encoded data based on the EG1 and EG2 standards are included. The video data input / output device 107 includes, for example, S
Video data is input / output to / from each terminal based on the DI (Serial Digital Interface) standard. The video data input / output device 107 is connected to each terminal via a communication line 600a such as a coaxial cable, an optical fiber cable, or a shielded twisted pair (STP) cable compliant with the SDI standard. More specifically, the video data input / output device 107 has a card member to which the above-described communication line is connected, and is connected to each terminal. The command input / output device 108 is, for example, a communication line 600b such as RS422.
Connected to each terminal. Similarly to the video data input / output device 107, the command input / output device 108 has a card member to which the above-mentioned communication line is connected, and is connected to each terminal.

[Software Configuration of Video Server]
FIG. 2 is a functional module configuration diagram showing a software configuration of the video server device shown in FIG. As shown in FIG. 2, the software of the video server device 1 of the present embodiment includes a command input / output processing unit 20 divided for each function unit.
1. Command interpretation processing unit 202, resource control processing unit 2
03, a disk control processing unit 204, a video data transfer processing unit 205, and a video data input / output processing unit 206. The command input / output processing unit 201 is software for transmitting and receiving a command Cmd with each terminal. Specifically, the command input / output processing unit 201
Is a command Cmd for instructing an interrupt received from each terminal via the command input / output device 108 (FIG. 1), or the MPU 101 (FIG. 1) via the command input / output device 108
(Inquiry) command Cmd received from
It is determined which command Cmd has been received. The command input / output processing unit 201 passes the received command Cmd to the command interpretation processing unit 202.

The command interpretation processing section 202 determines and interprets the command Cmd from the command input / output processing section 201. The command interpretation processing unit 202 interprets the interpreted command Cm
Based on d, the processing required to execute the command Cmd is performed by the resource processing unit 203 and the disk control processing unit 20.
4. Request the video data transfer processing unit 205 and the video data input / output processing unit 206. Also, the command interpretation processing unit 202 requests the command input / output processing unit 201 to perform a response process to the received command Cmd. The resource control processing unit 203 is software having a function of always managing the currently available bandwidth of the video server device 1 and allocating the bandwidth according to the type of the command Cmd.
With the function of the resource control processing unit 203, the video server device 1 of the present embodiment can dynamically change the bandwidth management according to the load situation, and can easily exhibit the maximum capacity (details). Will be described later).

The disk control processing unit 204 is a module that controls processing for reading video data from the disk 106 (FIG. 1) during reproduction and processing for writing to the disk 106 during recording. As is well known, in the video server device 1, interruption of video data at the time of reproduction and recording is not allowed. For this reason, the disk control processing unit 204 controls the read processing or the write processing of the video data in the disk control device 105 (FIG. 1) so that the video data is not interrupted. In the reading process or the writing process, the video data is input / output in the band allocated by the resource control processing unit 203. The video data transfer processing unit 205 is software that performs data transfer processing between the disk control processing unit 204 and the video data input / output processing unit 206. In this data transfer processing, the video data transfer processing unit 205 transfers video data using the band allocated by the resource control processing unit 203. The video data input / output processing unit 206 performs an output process of outputting video data from the video data transfer processing unit 205 to the terminal via the video data input / output device 107 (FIG. 1) during reproduction. Further, the video data input / output processing unit 206 performs an input process of transferring video data input from the terminal via the video data input / output device 107 to the video data transfer processing unit 205 during recording.

[Processing Operation of Command Interpretation Processing Unit] FIG.
3 is a flowchart illustrating a processing operation of a command interpretation processing unit illustrated in FIG. 2. The program of the flowchart shown in FIG. 3 is executed for each terminal connected to the video server device 1. As shown in FIG. 3, first, the command input / output processing unit 201
It is determined whether the command Cmd has been received in (FIG. 1) (step S1). When the command Cmd has not been received, the command input / output processing unit 201 enters a standby state. When receiving the command Cmd, the command input / output processing unit 201 determines that the received command Cmd is
After determining which command Cmd of polling from terminal 1 (FIG. 1) or interruption from the terminal has been received, the command Cmd is passed to the command interpretation processor 202. Next, the command interpretation processing unit 202 determines whether the received command Cmd is a Stop command for stopping the operation (Step S2). When a Stop command is received, it is not necessary to secure a band necessary for reproducing or recording video data. For this reason, the command interpretation processing unit 2
02 issues a bandwidth release event to release the bandwidth allocated to the terminal to the resource control processing unit 203,
The release of the band is notified (step S3). Thereafter, the command interpretation processing unit 202 proceeds to step S9 described below.

In step S2, if the received command Cmd is not a Stop command, the command interpretation processing unit 202 checks whether the command Cmd is a band-required command that requires a band to be allocated to the terminal (step S4). . In the broadcasting industry and the like, control command protocols such as Odetics and Louth that use RS422 as a communication line are used as standard, but not all of these commands require a band. For example, among the commands specified in the Odetics, a playback (Play) command and the like are included in the bandwidth required command, but a list (List) command and the like are commands that do not require the bandwidth. Note that a specific example of the bandwidth required command will be described later with reference to FIG. If the received command Cmd is a bandwidth required command, the command interpretation processing unit 20
2 checks whether another band required command is currently being executed (step S5). More specifically, the command interpretation processing unit 202 determines whether or not a band has been allocated to the terminal.
Contact On the other hand, if it is not a bandwidth required command,
Proceed to step S9.

When executing the bandwidth required command, the command interpretation processing unit 202 issues a bandwidth release event for releasing the bandwidth allocated to the terminal to the resource control processing unit 203 to notify the release of the bandwidth ( Step S
6). As a result, the processing of the executed band required command is stopped. After that, the command interpretation processing unit 202
Issues a bandwidth acquisition event to the resource control processing unit 203 in order to secure a bandwidth for executing the bandwidth required command received this time, and requests bandwidth allocation (step S7). Also, in step S5, if the bandwidth required command has not been executed, the command interpretation processing unit 2
02 performs the process shown in step S7. continue,
The command interpretation processing unit 202 secures an available bandwidth,
It is determined whether or not it has been acquired (step S8).
Specifically, when the allocated bandwidth is notified from the resource control processing unit 203, the command interpretation processing unit 202 determines that the bandwidth has been acquired.

Next, when the bandwidth is acquired, the command interpretation processing unit 202 transmits the acquired bandwidth together with the received bandwidth required command to the disk control processing unit 204, the video data transfer processing unit 205, and the video data input / output processing unit 206. , And requests processing required to execute the bandwidth required command (step S9). If the command Cmd received this time is a Stop command in step S9, the command interpretation processing unit 202 requests the disk control unit 204 to stop the currently executing process. In step S9, if the command Cmd received this time is a command that does not require a band, the disk control unit 204 and the video data input / output processing unit 206 are requested to perform processing necessary to execute the command. Next, the command interpretation processing unit 202 requests the command input / output processing unit 201 to transmit a command response to the terminal (step S10). On the other hand, if the command interpretation processing unit 202 cannot allocate a band from the resource control processing unit 203 in step S8, the process returns to step S1.

[Processing Operation of Resource Control Processing Unit] FIG.
3 is a flowchart illustrating a processing operation of a resource control processing unit illustrated in FIG. 2. Only one program of the flowchart shown in FIG. 4 is executed in the entire video server device 1. As shown in FIG. 4, the resource control processing unit 203
Waits until a bandwidth acquisition event or a bandwidth release event is received from the command interpretation processing unit 202 (step S11). Subsequently, when an event is received from the command interpretation processing unit 202, the resource control processing unit 203 determines whether a bandwidth acquisition event has been received (step S12). When a bandwidth acquisition event is received, the resource control processing unit 203 calculates and allocates an available bandwidth for the required bandwidth command based on the type of the received required bandwidth command and the managed maximum available bandwidth ( Step S13). At this time, if there is a margin in the maximum available bandwidth, the resource control processing unit 203 calculates to allocate the maximum allocable bandwidth described later in the bandwidth required command.

Next, the resource control processing unit 203 sends the command interpretation processing unit 2 to notify the terminal of the allocated bandwidth.
02 (step S14). If the bandwidth cannot be allocated, the resource control processing unit 203 sets “0” as the allocated bandwidth to the command interpretation processing unit 20.
Tell 2 Subsequently, the resource control processing unit 203 recalculates the maximum available bandwidth (step S15), and holds the recalculated maximum available bandwidth. Step S above
In step 12, if the received event is not a bandwidth acquisition event, the resource control processing unit 203 determines whether a bandwidth release event has been received (step S1).
6). If the received event is not a band release event, the resource control processing unit 203 returns to step S11 and enters a standby state. On the other hand, when receiving the band release event, the resource control processing unit 203 takes in the available band allocated to the terminal into the managed maximum available band (step S17). After that, the resource control processing unit 203 recalculates the maximum available bandwidth (step S15), and holds the recalculated maximum available bandwidth.

[Specific Example of Band Required Command] FIG.
FIG. 4 is an explanatory diagram showing a specific example of a bandwidth required command in the video server device shown in FIG. The minimum required bandwidth shown in FIG. 5 is the minimum required bandwidth for executing the required bandwidth command, and the maximum allocable bandwidth is the maximum available bandwidth for the required bandwidth command. In FIG. 5, playback (Play) and recording (Re
cord), maximum forward speed playback (Fast Forward), maximum reverse speed playback (Rewind), variable speed playback (Variable Pla
y) and jump play (Jog Play) are band required commands that always require a constant band in any case. 1 / n times slow playback (n is an integer) is 1 / n
This is a band required command that requires only a band proportional to the double speed. For example, at the time of 1/3 speed slow reproduction, a band of 1/3 of that at the time of normal reproduction may be allocated. Cue Up is a command for filling a buffer provided between the video server device and each terminal. File transfer (FTP) is a command for transferring video data in file units. Note that, for example, MPEG1 and MPEG
In video data compressed and encoded based on the two standards, specific values of the minimum required bandwidth of the video data (video stream) are 1.5 Mbps and 6 Mbps, respectively.

Here, the video server device 1 of the present embodiment,
The effect of the bandwidth management method will be specifically described. In the following description, a video server device having a transfer capability of up to six video streams will be described as an example. Also, a case where a cue-up command is received from one terminal when input / output (transfer) processing of a video stream is not performed on the video server device will be described. In the conventional video server device, as described above, a band is fixedly allocated to one terminal. For this reason, in the conventional video server device, if only one terminal can recognize a band up to a maximum of one video stream, for example, the same time as the reproduction is required to first fill the buffer. More specifically, if a terminal is provided with a buffer for storing 24 frames, the video data is 30 frames / second in the NTSC system. Therefore, in the conventional video server device, it took 0.8 seconds to fill the buffer with the video data. On the other hand, in the video server device 1 of the present embodiment, it is possible to allocate six bands, which are the maximum capabilities, to terminals. Therefore, in the video server device 1 of the present embodiment, the processing time required for filling the buffer with the video data can be reduced to 0.13 (= 0.8 / 6) seconds.

As described above, in the video server device 1 of this embodiment, when a command from a terminal is received, the MPU
The bandwidth allocated to the terminal is calculated and determined based on the command type illustrated in FIG. 5 and the currently available (maximum) available bandwidth managed by the resource control unit 101 (resource control unit 203). As a result, the video server apparatus 1 of the present embodiment can allocate the maximum allocable bandwidth to the command, and can easily exhibit the maximum capacity of the video server apparatus 1.

<< Second Embodiment >> FIG. 6 is a block diagram showing a specific example in which a video server apparatus according to a second embodiment of the present invention and a plurality of terminals are connected. In this embodiment, in the configuration of the video server device, the command with the highest priority is preferentially processed based on the command priority set in advance. The other parts are the same as those of the first embodiment, and the duplicated description thereof will be omitted. In the following description, for the sake of simplicity,
For example, a case where four terminals are connected to a video server device will be described. As shown in FIG. 6, a monitor A 601 and a terminal A 602 are connected to the video server device 1. The monitor A 601 displays video data and the like reproduced by a reproduction command of the terminal A 602.
The terminal A 602 outputs a command to the video server device 1 and performs the operation of the video server device 1. The monitor A 601 and the video server device 1 are connected via a communication line 600a.
As shown in FIG.
01 for transmitting video data to the coaxial cable 609
Connected by The terminal A 602 and the video server device 1 are connected via a communication line 600b (FIG. 1) RS422.
610, a command and a command response are transmitted and received between the terminal A 602 and the video server device 1. The terminal A 602 is connected to the communication line 600a.
Are connected to the video server device 1 by an optical fiber cable 611 included in the server, and file transfer for an FTP command and transfer of video data to be recorded in the video server device 1 are performed. Similarly, the video server device 1 includes a monitor B 603 and a terminal B 604, a monitor C 605 and a terminal C 606, and a monitor D 607 and a terminal D 608.
Is connected.

In the video server device 1 of the present embodiment, as shown in FIG. 7, for example, priorities are set in advance based on the types of commands. The priority of this command is stored in the disk 106 (FIG. 1). FIG.
FIG. 9 is an explanatory diagram showing an example of a command priority order in the video server device according to the second embodiment of the present invention. The video server device 1 of the present embodiment is configured to, when receiving a plurality of commands, preferentially process a command having a smaller numerical value (higher priority) in the priority column of FIG.
Specifically, in the video server device 1 of the present embodiment,
The MPU 101 (FIG. 1) performs bandwidth management so as to preferentially process a command required to transfer video data in real time according to the real-time nature of the video data. In other words, as shown in FIG. 7, the MPU 101 gives priority to each command from the playback command, which is particularly required to transfer video data in real time, to the 4 × speed recording command, over the cue-up command and the file transfer command. To process. Also, MPU 101
When a cue-up command and a file transfer command are received at the same time, a cue-up command required to transfer video data in real time has priority over a file transfer command not required to transfer video data in real time. To process. Furthermore, MPU
101, as in the first embodiment, constantly grasps and manages the maximum available bandwidth. Therefore, MPU 1
No. 01 can determine the allocation of the bandwidth to the terminal based on the type of the received command, the priority of the command set in advance, and the managed maximum available bandwidth. Thus, the video server device 1 of the present embodiment can perform the process of transferring the video data in real time preferentially while maximizing the performance.
Note that, on the software of the video server device 1 of the present embodiment, the resource control processing unit 203 (FIG. 2) performs the above-described bandwidth management (details will be described later).

[Processing Operation of Resource Control Processing Unit] The operation of the video server device 1 according to the present embodiment will be specifically described below with reference to FIGS. 8, 9 and 10. FIG.
It is a flowchart which shows the processing operation of the resource control processing part in the video server apparatus of the 2nd Example of this invention. FIG. 9 is an explanatory diagram showing an example of an allocated bandwidth allocated to each terminal before receiving a cue-up command in the video server device of the second embodiment of the present invention, and FIG. FIG. 9 is an explanatory diagram illustrating an example of an allocated band allocated to each terminal after receiving a cue-up command in the video server device of the embodiment. In the following description, an operation different from that of the first embodiment will be mainly described, taking a video server device having a transfer capability of up to six video streams as an example. In the configuration shown in FIG.
A case where the terminal D 608 outputs a cue-up command to the video server device 1 while the terminal 602 and the terminal B 604 are executing a playback command and the terminal C 606 is executing a file transfer command will be described.

When the video server device 1 receives the cue-up command from the terminal D 608, the resource control processing section 203 executes the processing shown in step S18 in FIG.
Based on the type and priority of the command and the maximum available bandwidth, allocation of available bandwidth to the queue-up command is calculated. At this time, as shown in FIG. 7, the priorities of the commands are preset such that the reproduction command has the highest priority, the cue-up command has the next highest priority, and the file transfer command has the lowest priority. I have. Therefore, the resource control processing unit 203
Are assigned bands 1, 1, and 4 respectively assigned to terminal A 602, terminal B 604, and terminal C 606 shown in FIG.
A terminal 602, terminal B 604, and terminal C shown in FIG.
The bandwidth is changed to the allocated bandwidths 1, 1, 0, and 4 respectively allocated to the mobile station 606 and the terminal D 608. More specifically, as shown in FIG. 9, before receiving the cue-up command, the resource control processing unit 203 uses the maximum allocatable bandwidth for the playback commands issued by the terminal A 602 and the terminal B 604. One band (shown in FIG. 5) is allocated, and four bands (4 = 6-), which are the maximum available bands for the file transfer command issued by the terminal C 606, are allocated.
1-1) is assigned. Further, as shown in FIG. 10, after receiving the queue-up command, the terminal D 608 issues a command so that the resource control processing unit 203 processes the queue-up command with a higher priority than the file transfer command. Allocated four bands, which are the maximum available bands, for the queue-up command
The bandwidth is set to 0 for the above-mentioned file transfer command. As described above, in the video server device 1 of the present embodiment, it is possible to preferentially process a command having a high priority by suppressing the allocation of a band to a command having a low priority.

As described above, in the video server device 1 of this embodiment, when a plurality of commands are received, the MPU 1
01 (the resource control unit 203) calculates and determines the bandwidth to be assigned to the terminal based on the command type and priority illustrated in FIG. 7 and the (maximum) available bandwidth managed at the present time. Accordingly, in the video server device 1 of the present embodiment, in addition to the effects of the first embodiment, in addition to the effect of the file transfer which is a non-real-time process, the video server device 1 can perform a data transfer process such as a queue-up command that requires a real-time property. It is possible to preferentially allocate the band.

<< Third Embodiment >> FIG. 11 shows a third embodiment of the present invention.
It is an explanatory view showing an example of a priority order of a terminal in a video server apparatus which is an example of an example. In this embodiment, in the configuration of the video server apparatus, processing is performed preferentially from the command from the terminal having the higher priority based on the priority of the terminal set in advance. The other parts are the same as those of the first embodiment, and the duplicated description thereof will be omitted. In the following description, as shown in FIG.
Four terminals A 602, terminal B 604, terminal C 60
6 and the case where the terminal D 608 is connected to the video server device 1 will be described. In the video server device 1 of the present embodiment, the terminal A 602, the terminal B 604, the terminal C
For the terminal 606 and the terminal D 608, band management is performed based on a preset terminal priority order so that, for example, a terminal having a smaller numerical value in the priority order column of FIG. Specifically, in the video server device 1 of the present embodiment, as shown in FIG. 11, the MPU 101 processes the commands issued by the terminal A 602 and the terminal B 604 with the highest priority, and then the terminal C 606 The command issued by the terminal D 608 is processed with priority over the issued command. Note that the priority of this terminal is
(FIG. 1). Further, MPU 101
, As in the first embodiment, always grasps and manages the maximum available bandwidth. Therefore, MPU 101
It is possible to determine the band allocation to the terminal based on the type of the received command, the preset priority of the terminal, and the managed maximum available band. Thereby, in the video server device 1 of the present embodiment,
A command issued by a terminal with a higher priority can be preferentially processed while maximizing the capability. Note that, on the software of the video server device 1 of the present embodiment, the resource control processing unit 203 (FIG. 2) performs the above-described bandwidth management (details will be described later).

[Processing Operation of Resource Control Processing Unit] Hereinafter, the operation of the video server device 1 of the present embodiment will be specifically described with reference to FIGS. 12, 13 and 14. FIG.
FIG. 2 is a flowchart showing the processing operation of the resource control processing unit in the video server device according to the third embodiment of the present invention. FIG. 13 is an explanatory diagram showing an example of an allocated bandwidth allocated to each terminal before receiving a cue-up command in the video server device of the third embodiment of the present invention, and FIG. FIG. 9 is an explanatory diagram illustrating an example of an allocated band allocated to each terminal after receiving a cue-up command in the video server device of the embodiment. In the following description, an operation different from that of the first embodiment will be mainly described, taking a video server device having a transfer capability of up to six video streams as an example. Further, in the configuration shown in FIG.
A case where the terminal D 608 outputs a cue-up command to the video server device 1 while the terminal A 602 and the terminal B 604 are executing a playback command and the terminal C 606 is executing a 4 × speed playback command will be described. .

When the video server device 1 receives the cue-up command from the terminal D 608, the resource control processing unit 203 determines the type of the command and the terminal priority set in advance as shown in step S19 in FIG. ,
Then, based on the maximum available bandwidth, the allocation of the available bandwidth to the queue-up command is calculated. At this time, as shown in FIG. 11, the priorities of the terminals are set such that terminal A 602 and terminal B 604 have the highest priority, terminal D 608 has the highest priority, and terminal C 606 has the lowest priority. Is set. Therefore, the resource control processing unit 203 allocates the allocated bands 1, 1, and 4 respectively allocated to the terminal A 602, the terminal B 604, and the terminal C 606 illustrated in FIG. 13 to the terminal A 602, the terminal B 604, and the terminal illustrated in FIG. The assigned bandwidth is changed to 1, 1, 0, and 4 assigned to the terminal C 606 and the terminal D 608, respectively.
As described above, since the bandwidth allocated to the terminal C 606 is changed to 0, the process of transferring the video data in response to the quadruple speed playback command is stopped. Also, to the cue-up command from the terminal D 608, four bands, which are the maximum available bands at the present time, are allocated, and the video data transfer processing for the cue-up command is performed.

As described above, in the video server device 1 of the present embodiment, when a command is received from a plurality of terminals,
The PU 101 (resource control unit 203) calculates and determines the bandwidth to be allocated to the terminal based on the type of command, the priority of the terminal illustrated in FIG. 11, and the (maximum) available bandwidth managed at the present time. ing. Thereby, in addition to the effects of the first embodiment, the video server device 1 of the present embodiment can preferentially process a command issued by a terminal with a higher priority.

<< Fourth Embodiment >> FIG. 15 shows a fourth embodiment of the present invention.
It is an explanatory view showing a concrete example of a request registration table which manages a request from a terminal in a video server device of an example. In this embodiment, in the configuration of the video server device, when the same video data transfer request is input from a plurality of terminals,
It is configured to collectively reproduce as one transfer request from the video data storage unit (disk) and perform transfer processing. The other parts are the same as those of the first embodiment, and the duplicated description thereof will be omitted. In the video server device 1 of the present embodiment, when the command input / output device 108 (FIG. 1) receives a command, the MPU 101 (FIG. 1) transmits predetermined information including the terminal that transmitted the command, the type of the command, and the like. Store in the request registration table. Specifically,
In the request registration table, as shown in FIG. 15, for each terminal, the reception time of the command, the type of the reception command, the video data file name required for the reception command,
And information indicating the start frame value (time code value) of the video data. This request registration table is stored in the disk 106 when the video server 1 operates.
(FIG. 1).

Further, the MPU 101 determines whether or not a transfer request for the same video data has been requested from a plurality of terminals within a certain period (for example, 33 msec). When a plurality of terminals request the same video data transfer request, the MPU 101 collects the same video data as one transfer request, and reads the same video data from the disk 106 (FIG. 1). Work). As a result, the video data is transferred to the disk 106
Is transferred to the video data input / output device 107 (FIG. 1) in one band through the disk control device 105, and is transferred to a plurality of terminals. As described above, the video server device 1 of the present embodiment can process a request for transfer processing of the same video data from a plurality of terminals by allocating one band.

More specifically, in the case illustrated in FIG.
The MPU 101 provides the scene 1. The playback command from the 00 hour 00 minute 00 second 00 frame of (moving image) is received from the terminal A,
A reproduction command of the same video data as that of the terminal A is received from the terminal C at 0: 10: 00: 10 ms. MPU10
Since terminal 1 receives these playback commands within the above-mentioned fixed period, terminal A and terminal C are stored in the same requesting terminal list 1 (not shown), and a band is allocated as one transfer request. Perform bandwidth management. In the software of the video server device 1 of the present embodiment, the functions of the resource control processing unit 203 (FIG. 2) and the disk control processing unit 204 (FIG. 2) are changed as compared with those of the first embodiment. Thereby, the above-described processing operations and effects can be obtained (details will be described later).

[Processing Operation of Resource Control Processing Unit] First, the processing operation of the resource control processing unit 203 of this embodiment will be described with reference to FIG. FIG. 16 is a flowchart showing the processing operation of the resource control processing unit in the video server device according to the fourth embodiment of the present invention. The program of the flowchart shown in FIG. 16 is executed only once in the entire video server device 1 as in the first embodiment, but in order to make the description clear,
The terminal m and the terminal n will be described as an example. As shown in FIG. 16, the resource control processing unit 203 waits until a bandwidth acquisition event or a bandwidth release event is received from the command interpretation processing unit 202 (FIG. 2) (step S20). Subsequently, when receiving an event from the command interpretation processing unit 202, the resource control processing unit 203 determines whether or not a bandwidth acquisition event issued by the terminal m has been received (step S21).

When a bandwidth acquisition event is received, the resource control processing unit 203 calculates an available bandwidth for the required bandwidth command based on the type of the received required bandwidth command and the managed maximum available bandwidth. (Step S22). At this time, if there is room in the available bandwidth, the resource control processing unit 203 calculates to allocate the maximum allocable bandwidth in the bandwidth required command. Further, the resource control processing unit 20 of the present embodiment
In step 3, as shown in step S22, a process of registering a request (bandwidth required command) from the terminal m in the request registration table illustrated in FIG. Subsequently, the resource control processing unit 203 determines whether or not another terminal n has requested reproduction to the same place within a certain period (step S23). That is, the resource control processing unit 203
Determines whether a playback command of the same video data has been received from the terminal m and the terminal n within a certain period.

If the same video data reproduction command has been received from the terminals m and n within a certain period of time, the resource control processing unit 203 puts the terminal m and the terminal n in the same request terminal list 1 and performs disk control. The same event described later is notified to the processing unit 204 (step S24). After that, the resource control processing unit 203 notifies the command interpretation processing unit 202 to notify the terminal of the allocated bandwidth (step S25). On the other hand, in the above step S23, the terminal m and the terminal n
If not received from the resource control processing unit 203
Proceeds to step S25 without performing the processing operation shown in step S24, and notifies the command interpretation processing unit 202 to notify the terminal m of the allocated band. continue,
The resource control processing unit 203 recalculates the maximum available bandwidth (step S26), and holds the recalculated maximum available bandwidth.

In step S21, if the received event is not a bandwidth acquisition event, the resource control processing unit 203 determines whether a bandwidth release event has been received (step S27). If the received event is not a band release event, the resource control processing unit 203 returns to step S20 and enters a standby state. Subsequently, the resource control processing unit 203 checks whether or not the terminal m is included in the same request list 1 (step S2).
8). If the terminal m is not in the same request list 1,
The resource control processing unit 203 captures the available bandwidth allocated to the terminal m into the managed maximum available bandwidth (step S29), and performs the processing operation shown in step S26 described above. On the other hand, if the terminal m is in the same request list 1, the resource control processing unit 203 notifies the disk control processing unit 204 of the same release event, and deletes the terminal m from the same request list 1 (step S30). .
Thereafter, the resource control processing unit 203 performs the processing operation shown in step S26 described above.

[Processing Operation of Disk Control Processing Unit] Next, the processing operation of the disk control processing unit 204 of this embodiment will be described with reference to FIG. FIG. 17 is a flowchart showing a processing operation of the disk control processing unit in the video server device according to the fourth embodiment of the present invention. In the following description, only processing operations corresponding to the same event or the same cancellation event notified from the resource control processing unit 203 will be described, and other processing operations will be general processing operations for controlling a disk. Therefore, the description is omitted.
As shown in FIG. 17, the disk control processing unit 204 waits until receiving the same event or the same cancellation event from the resource control processing unit 203 (step S3).
1). Subsequently, when an event is received from the resource control processing unit 203, the disk control processing unit 204 determines whether the same event has been received (step S3).
2).

When the same event is received, the disk control processing section 204 requests the disk 106 (FIG. 1) as a single request for reproduction requests from terminals belonging to the same request list 1 within a predetermined period (step). S33).
On the other hand, if the same event has not been received in step S32, the disk control processing unit 204 determines whether the same release event has been received (step S34). If the same release event has not been received, the disk control processing unit 204 returns to step S31 and enters a standby state. Also, when the same release event is received,
The disk control processing unit 204 stops processing requests for reproduction within a certain period from terminals belonging to the same request list 1 as one request (step S35).

As described above, in the video server device 1 of the present embodiment, when the same video data transfer request from a plurality of terminals is received within a certain period, the MPU 101 (resource control unit 203) executes one request. And the same video data is reproduced and transferred. Thereby, the video server device 1 of the present embodiment can process a request for the same video data transfer processing from a plurality of terminals by allocating one band, and in addition to the effect of the first embodiment, The load on the video server device 1 can be reduced.

As described above, any of the bandwidth management methods of the video server device in the above-described first to fourth embodiments can be computer-programmed. It is also possible to provide the bandwidth management method of the present application. The recording medium referred to here is a floppy disk, CD-R
OM, DVD, magneto-optical disk, and removable hard disk. Also, the first to fourth embodiments may be appropriately combined to perform band management.

[0052]

According to the video server apparatus and the bandwidth management method of the present invention, when a command is received from a terminal,
The bandwidth to be allocated to the terminal is determined based on the type of the received command and the currently available bandwidth managed. Thus, in the video server device and the bandwidth management method of the present invention, the bandwidth management can be dynamically changed according to the load status of the video server device, and the maximum capacity of the video server device can be easily reduced. Can be demonstrated.

A video server device according to another aspect of the present invention,
In the band management method, when a plurality of commands are received, the band to be allocated to the terminal is determined based on the types and priorities of the commands and the currently available band managed. Thus, in the video server device and the bandwidth management method of the present invention, the bandwidth management can be dynamically changed according to the load status of the video server device, and the maximum capacity of the video server device can be easily reduced. Can be demonstrated. Further, in the video server device and the band management method of the present invention,
It is possible to allocate a band with priority to data transfer processing that requires real-time performance over non-real-time data transfer processing.

A video server device according to another aspect of the present invention,
And in the band management method, when a command is received from a plurality of terminals, a band to be allocated to the terminal is determined based on the type of command, the priority of the terminal, and the currently available band being managed. Make up. Thus, in the video server device and the bandwidth management method of the present invention, the bandwidth management can be dynamically changed according to the load status of the video server device, and the maximum capacity of the video server device can be easily reduced. Can be demonstrated. Further, in the video server device and the bandwidth management method of the present invention, it is possible to preferentially process a command issued by a terminal having a higher priority.

A video server device according to another aspect of the present invention;
Also, the bandwidth management method is configured such that, when transfer requests for the same video data from a plurality of terminals are received within a predetermined period, the same video data is collectively reproduced as one request and transferred. Thus, in the video server device and the bandwidth management method of the present invention, the bandwidth management can be dynamically changed according to the load status of the video server device, and the maximum capacity of the video server device can be easily reduced. Can be demonstrated. Further, in the video server device and the band management method of the present invention, a single band can be assigned to process a request for transfer processing of the same video data from a plurality of terminals, thereby reducing the load on the video server device. it can. Further, since the bandwidth management method of the present invention can be made into a computer program as shown in each of the above-described first to fourth embodiments, the bandwidth management method of the present invention can be executed by a computer. It can be recorded on a medium and executed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a hardware configuration of a video server device according to a first embodiment of the present invention.

FIG. 2 is a functional module configuration diagram showing a software configuration of the video server device shown in FIG. 1;

FIG. 3 is a flowchart showing a processing operation of a command interpretation processing unit shown in FIG. 2;

FIG. 4 is a flowchart showing a processing operation of a resource control processing unit shown in FIG. 2;

FIG. 5 is an explanatory diagram showing a specific example of a bandwidth required command in the video server device shown in FIG. 1 and a bandwidth required by each bandwidth required command.

FIG. 6 is a configuration diagram showing a specific example in which a video server device according to a second embodiment of the present invention and a plurality of terminals are connected;

FIG. 7 is an explanatory diagram showing an example of command priorities in the video server device according to the second embodiment of the present invention;

FIG. 8 is a flowchart showing a processing operation of a resource control processing unit in the video server device according to the second embodiment of the present invention;

FIG. 9 is an explanatory diagram showing an example of an allocated bandwidth allocated to each terminal before receiving a cue-up command in the video server device according to the second embodiment of the present invention.

FIG. 10 is an explanatory diagram showing an example of an allocated bandwidth allocated to each terminal after receiving a cue-up command in the video server device according to the second embodiment of the present invention;

FIG. 11 is an explanatory diagram showing an example of terminal priorities in a video server device according to a third embodiment of the present invention;

FIG. 12 is a flowchart illustrating a processing operation of a resource control processing unit in the video server device according to the third embodiment of the present invention;

FIG. 13 is an explanatory diagram showing an example of an allocated bandwidth allocated to each terminal before receiving a cue-up command in the video server device according to the third embodiment of the present invention.

FIG. 14 is an explanatory diagram showing an example of an allocated bandwidth allocated to each terminal after receiving a cue-up command in the video server device according to the third embodiment of the present invention.

FIG. 15 is an explanatory diagram showing a specific example of a request registration table for managing requests from terminals in the video server device according to the fourth embodiment of the present invention.

FIG. 16 is a flowchart illustrating a processing operation of a resource control processing unit in a video server device according to a fourth embodiment of the present invention.

FIG. 17 is a flowchart showing a processing operation of a disk control processing unit in the video server device according to the fourth embodiment of the present invention;

[Explanation of symbols]

 1 Video Server Device 101 MPU 102 Bus Bridge Unit 103 Main Memory 104 Bus 105 Disk Controller 106 Disk 107 Video Data Input / Output Device 108 Command Input / Output Device

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5C053 FA28 FA29 GA11 GB21 GB37 GB40 HA21 HA23 HA24 HA25 KA24 KA30 LA11 LA20 5C064 BA07 BB05 BB10 BC06 BC10 BC25 BD02 BD08 BD09 5K030 GA08 HB01 HB02 KA01 KA02 KA11

Claims (12)

[Claims] 1. A video server device connected to at least one terminal and for inputting / outputting digital data including video data in response to a command from the terminal, wherein a command input for inputting a command from the terminal is provided. An output unit, a video data storage unit that holds video data, a video data input / output unit that inputs and outputs the video data, and a disk control unit that controls the video data storage unit. The video data storage unit and the video data Manages the bandwidth for transferring video data between the input and output units, when receiving a command from the terminal, based on the type of the received command and the currently available bandwidth being managed,
A video server device configured to determine a band to be allocated to the terminal. 2. A video server device connected to at least one terminal for inputting / outputting digital data including video data in response to a command from the terminal, wherein a command input for inputting a command from the terminal is provided. An output unit, a video data storage unit that holds video data, a video data input / output unit that inputs and outputs the video data, and a disk control unit that controls the video data storage unit. The video data storage unit and the video data Manages the bandwidth for transferring video data between the input and output units, and when multiple commands are received, the type of command, the priority of a preset command, and the currently available bandwidth managed A video server device configured to determine a band to be allocated to a terminal based on the video server. 3. A video server device connected to at least one terminal and inputting / outputting digital data including video data in response to a command from the terminal, wherein a command input for inputting a command from the terminal is provided. An output unit, a video data storage unit that holds video data, a video data input / output unit that inputs and outputs the video data, and a disk control unit that controls the video data storage unit. The video data storage unit and the video data Manages the bandwidth for transferring video data between the input and output units, and when commands are received from multiple terminals, the types of commands, the priorities of the preset terminals, and the currently available managed A video server apparatus configured to determine a bandwidth to be allocated to a terminal based on a minimum bandwidth. 4. A video server device connected to at least one terminal and for inputting / outputting digital data including video data in response to a command from the terminal, wherein a command input for inputting a command from the terminal is provided. An output unit, a video data storage unit that holds video data, a video data input / output unit that inputs and outputs the video data, and a disk control unit that controls the video data storage unit. The video data storage unit and the video data By managing the band for transferring video data between the input and output units, when receiving a transfer request of the same video data from a plurality of terminals within a certain period, the same video data is reproduced as one request collectively. A video server device configured to perform transfer processing. 5. A bandwidth management method for a video server device connected to at least one terminal and inputting / outputting digital data including video data in response to a command from the terminal, comprising: A command input step for inputting, a command interpretation step for interpreting the command input in the command input step, and transferring the video data between the video data storage unit and the video data input / output unit using the command interpreted in the command interpretation step. If the command is a band required command that requires a predetermined band, a band determining step of determining a band to be allocated to the terminal based on the type of the interpreted command and the currently available band managed is provided. Bandwidth management method for a video server device. 6. A bandwidth management method for a video server device connected to at least one terminal and inputting / outputting digital data including video data in response to a command from the terminal, comprising: A command input step for inputting, a command interpretation step for interpreting the command input in the command input step, and transferring the video data between the video data storage unit and the video data input / output unit using the command interpreted in the command interpretation step. In the case of a band required command requiring a predetermined band, the type of the interpreted command, the priority of a preset command,
And a bandwidth determining step of determining a bandwidth to be allocated to the terminal based on a currently available bandwidth managed by the video server apparatus. 7. A bandwidth management method for a video server device connected to at least one terminal and inputting / outputting digital data including video data in response to a command from the terminal, comprising: A command input step for inputting, a command interpretation step for interpreting the command input in the command input step, and transferring the video data between the video data storage unit and the video data input / output unit using the command interpreted in the command interpretation step. If the command is a bandwidth required command that requires a predetermined bandwidth, based on the type of the interpreted command, the preset priority of the terminal, and the currently available bandwidth managed, Determining a bandwidth of the video server device. . 8. A bandwidth management method for a video server device connected to at least one terminal and inputting / outputting digital data including video data in response to a command from the terminal, comprising: A command inputting step for inputting, a command interpreting step for interpreting the command input in the command inputting step, a command interpreted in the command interpreting step, when the video data is transferred between the video data storage unit and the video data input / output unit. In the case of a band required command that requires the band, a determination step of determining whether the same video data transfer request as the band required command has been received from another terminal within a predetermined period, and the same as the band required command If a video data transfer request is received from another terminal within a certain period, A transfer step of combining the bandwidth required command and the transfer request from the another terminal into one request, and reproducing and transferring the same video data. 9. A command inputting step for inputting a command from a terminal, a command interpreting step for interpreting the command input in the command inputting step, and a command interpreted in the command interpreting step being used to input / output a video data storage unit and a video data input / output. If the command requires a predetermined band when transferring video data between the units, the command is allocated to the terminal based on the type of the interpreted command and the currently available band being managed. A recording medium recording a bandwidth management program, comprising: a bandwidth determination step of determining a bandwidth. 10. A command inputting step for inputting a command from a terminal, a command interpreting step for interpreting the command input in the command inputting step, and a command interpreted in the command interpreting step being used to input / output a video data storage unit and a video data input / output. In the case of a band required command that requires a predetermined band when transferring video data between the units, the type of the interpreted command, the priority of a preset command,
And a band determining step of determining a band to be allocated to the terminal based on the currently available band being managed. 11. A command inputting step of inputting a command from a terminal, a command interpreting step of interpreting the command input in the command inputting step, and a command interpreted in the command interpreting step being used to input / output a video data storage unit and a video data input / output. If the command is a bandwidth-required command that requires a predetermined bandwidth when transferring video data between units, the type of the interpreted command, the preset priority of the terminal, and the currently available managed A band determining step of determining a band to be allocated to the terminal based on the optimum band. 12. A command inputting step of inputting a command from a terminal, a command interpreting step of interpreting the command input in the command inputting step, wherein the command interpreted in the command interpreting step is a video data storage unit and a video data input / output unit. If the command is a band-required command that requires a predetermined band when transferring video data between the terminals, it is determined whether or not a transfer request for the same video data as the command requiring the band has been received from another terminal within a certain period of time The determination step, and if the same video data transfer request as the bandwidth required command has been received from another terminal within a certain period of time, the bandwidth required command and the transfer request from the different terminal are combined into one request A transfer step of reproducing and transferring the same video data. Storage medium that stores the processing program.