JP2000217076A - Video server device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a video server device that minimizes a damage to reproduced picture and audio data even when reading of moving picture data is failed. SOLUTION: The video server device is provided with a data read write controller 22 that reads moving picture data from a plurality of hard disks 1-10 and again reads the data when first reading is failed, a buffer 28 that temporarily stores moving picture data, a residual amount detector 30 that detects whether or not a data quantity stored in the buffer 28 is less than a preset residual quantity threshold and outputs an alarm signal when the data quantity is less than the residual threshold, and a controller that stops re-reading of the data read write controller 22 when an alarm signal is outputted, specifies data whose reading is failed and outputs data succeeding temporally to the failed data to the buffer 28 in place of the failed data.

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 used for providing moving images, a video library system, and the like.

[0002]

2. Description of the Related Art In recent years, MPEG (Moving Picture Exper
Data compression technology represented by the Digital Video Group, Inc., has advanced, and it has become possible to digitize moving images and record them. In addition, technology for distributing these via the Internet and cable television has been developed, and some have been put into practical use. I have. Digital signals are easy to remove noise even when long-distance communication is performed, and image quality and sound are hardly degraded by communication. Therefore, digital signals are likely to be used for general television broadcasting in the future.

[0003] Now, in practical video server apparatuses, apparatuses using a hard disk as a data recording medium have been put into practical use in view of access speed, recording capacity and the like. Further, in the current video server device, in order to improve the data writing and reading speed, data reading and writing are usually performed on a plurality of hard disks using a method called striping. The striping method is a type of method in which registered material data is distributed and stored on a plurality of hard disks.

[0004]

By the way, in a video server device, it is necessary to read temporally continuous data from a hard disk at predetermined time intervals due to the nature of data. Next, an inconvenience when data is not read at a fixed time interval will be described. FIG. 2 is a diagram illustrating a disadvantage when data is not read at a fixed time interval.

[0005] In FIG. 2, circles with symbols f _{6 to} f ₁₂ indicate frame numbers of moving image data. Frames of moving image data are fixed at fixed time intervals, for example, one frame is 33 ms. Now, the data of the sixth frame to which the reference numeral f ₆ is assigned is read out, and thereafter the reference numeral f 6
_It is assumed that a seventh frame to which ₇ is attached, an _eighth frame to which reference numeral f8 is attached, and so on are read.

[0006] Then, if the tenth frame code f ₁₀ is attached, and an error occurs such that the data read can not be read within a predetermined time interval from the hard disk where the data of the tenth frame is recorded The conventional device attempts to reread the data of the tenth frame. While performing the re-reading of the 10th frame the previous frame, i.e. data of the ninth frame is output (data of the frame 2, reference numeral f ₉ is attached is repeatedly output).

As described above, when an error occurs in reading data from the hard disk, not only the output of the data itself is delayed, but also the moving image is time-series data of images and sounds, so that subsequent data is reproduced. There was a problem that it became impossible. In order to solve this problem, it is conceivable to discard the data that failed to be read. However, simply discarding the data may cause a problem that the reproduction time is incorrect.

The present invention has been made in view of the above circumstances, and a video server apparatus capable of minimizing damage to reproduced images and sounds even when reading of moving image data fails. The purpose is to provide.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a data reading method for reading moving image data from a plurality of hard disks and re-reading the data if the reading fails. Means, a buffer for temporarily storing moving image data, and detecting whether or not the amount of data stored in the buffer is smaller than a predetermined remaining amount threshold, and determining whether the data amount is smaller than the remaining amount threshold. If the data is small, the remaining amount detection unit that outputs an alarm signal, and if the alarm signal is output, causes the data reading unit to stop re-reading, and specifies data that failed to be read, Control means for controlling output of temporally succeeding data to the buffer in place of the data. Also,
The present invention is characterized in that a memory device is provided between the data reading means and the buffer. In addition, according to the present invention, when the data reading unit fails to read the data, the data reading unit reads the data that follows temporally and outputs the data to the memory device, and the control unit controls the memory device. And outputting, to the buffer, temporally succeeding data in place of the data for which the reading has failed.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a video server device according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a video server device according to an embodiment of the present invention. As shown in FIG. 1, a video server device according to an embodiment of the present invention includes a plurality of hard disks 1 to 10 and a host computer 2.
It consists of 0.

The host computer 20 includes a data read / write control device 22 for controlling the reading and writing of data from and to the hard disks 1 to 10, a memory 24 for storing data read from the hard disks 1 to 10, Video interface card 2 which is an interface between host computer 20 and external equipment
6, the data read / write control device 22 and the memory 2
4 comprises a control device 32 for controlling the operation of FIG.

Moving image data is recorded on the hard disks 1 to 10 in a distributed manner for each frame as shown in FIG. The video interface card 26 includes a buffer 28 for temporarily storing input / output data with an external device,
It comprises a remaining amount detecting device 30 for detecting the remaining amount of data stored in the buffer 28. The remaining amount detection device 30 is connected to the control device 32 by a signal line 30a, and when the remaining amount of the buffer 28 becomes smaller than a preset remaining amount threshold value of the buffer 28, the control device 3 via the signal line 30a.
2 to output an alarm signal. The control device 32 is connected to the data read / write control device 22 by a signal line 32a, and is connected to the memory 24 by a signal line 32b.

The data read / write controller 22 and the memory 24 are connected by a data bus D1, and the memory 24 and the buffer 28 are connected by a data bus D2. Therefore, the data read from the hard disk devices 1 to 10 are stored in the data read / write control device 22, the data bus D1,
The data is output to the outside via the memory 24, the data bus D2, and the buffer 28 in this order.

Next, the operation of the video server device according to an embodiment of the present invention having the above configuration will be described. Hard disk 10 to the video server apparatus has some variation in response time to absolutely data read request from the host computer 20 because there is a seek and rotation waiting of the head.

In a broadcast station, when recording a transmission material, an ED
Generally, the TV2 material and the CM material cannot be compressed, so that the material is recorded and reproduced without being compressed. In such a video server device, it is assumed that reading of the tenth frame of the moving image data has failed, and an error retry of the hard disk has occurred. In addition, in this specification, the reading failure includes not only a case where the data cannot be read because the data is damaged, but also a case where the reading cannot be performed within a predetermined time.

In this case, when data is stored in a distributed manner using the striping method, even if the reading of one frame of the tenth frame is delayed and subsequent data reaches the host, the data is sequentially output. It is not possible to output the eleventh and subsequent frames because of necessity.

Therefore, if the user waits until the data of the tenth frame reaches the host computer 20, the reproduction is delayed as shown in FIG. When the 10th frame is skipped and output, the reproduction time is shortened by 33 mS (one frame time). If this occurs several times, the time is accumulated, and the time at which the material ends is greatly disturbed.

Accordingly, in the present embodiment, the video / audio data buffer 28 is provided in the video interface card 26, and the remaining amount of data stored in the buffer 28 becomes smaller than a predetermined remaining amount threshold. And a remaining detection device for detecting whether or not there is a fire.
That is, if a frame that should be read within a predetermined time is not read and a state in which the data stored in the buffer 28 is sequentially output continues, the buffer 28 eventually runs out.

If data reading from any of the hard disks 1 to 10 fails, the data read / write control device 22
Attempts to reread the frame that failed to be read. During this re-reading, data stored in advance is output from the buffer 28. It should be noted that data of a predetermined number of frames after the data of the tenth frame for which reading has failed is transferred from another hard disk to the memory 24.
Is read to The remaining amount detection device 30 compares the remaining amount of the buffer 28 with a predetermined remaining amount threshold, and
When the remaining amount becomes smaller than the predetermined remaining amount threshold, an alarm signal is output to the control device 32 via the signal line 30a.

When this alarm signal is input to the control unit 32, the control unit 32 specifies the data to be read again to the data read / write control unit 22,
2a, a cancel signal for canceling the reading of the data is output, and the last data output to the interface card 26 (in the present embodiment, the data of the ninth frame) is output to the tenth frame that failed to be read. Output in place of frame.

Then, the control device 32 reads the memory 2
The frames after the eleventh frame stored in No. 4 are sequentially output to the buffer. Therefore, in the present embodiment, the ninth frame is output instead of the tenth frame that should have been output, but the data after the occurrence of the error cannot be reproduced as in the related art. Also, there is no problem that the reproduction time is out of order.

In the example shown in this embodiment,
When a reading error occurs, the original frame is not displayed, but the frame is 33 ms as described above.
Since the time width is of the order, even if the data of one frame is different, the image and the sound to be reproduced can hardly be sensed by a human, so that the damage of the data can be minimized.

[0023]

As described above, according to the present invention, even if reading of moving image data from a hard disk fails, damage to reproduced images and sounds can be minimized. effective.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a video server device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a disadvantage when data is not read at a fixed time interval.

[Explanation of symbols]

1 to 10 hard disk 20 host computer 22 data read / write control device (data read means) 24 memory 26 video interface card 28 buffer 30 remaining amount detection device (remaining amount detection device) 32 control device (control means)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5B065 BA01 CE12 EK04 5C052 AA01 AA17 CC06 CC08 DD04 DD06 GA04 GA09 GB06 GB07 GC06 GD06 GD09 GE04 GF04 5C053 FA19 FA23 GA20 GB01 GB11 GB21 GB37 GB40 HA33 HB01 JA30 KA01 KA03 KA03

Claims (3)

[Claims] 1. A data reading means for reading moving image data from a plurality of hard disks and re-reading the data if the reading fails, a buffer for temporarily storing moving image data, A remaining amount detecting unit that detects whether the amount of data stored in the buffer is smaller than a preset remaining amount threshold and outputs an alarm signal if the data amount is smaller than the remaining amount threshold And when the alarm signal is output, causes the data reading means to stop rereading, specifies data that failed to be read, and outputs temporally succeeding data to the buffer in place of the data. A video server device, comprising: a control unit that performs control to perform the control. 2. The video server device according to claim 1, wherein a memory device is provided between said data reading means and said buffer. 3. The data reading means, if the data reading fails, reads out the temporally succeeding data and outputs the data to the memory device. The control means controls the memory device, 3. The video server device according to claim 2, wherein temporally succeeding data is output to the buffer in place of the data for which the reading has failed.