JP2004007075A - Video image recording apparatus and video image recording method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a video image recording device capable of preventing the wasteful consumption of the recording capacity of a video image file and the index file of the video image file and the reproduction error of those files. <P>SOLUTION: The video image recording apparatus is provided with a video image file inspecting and repairing means (115) for inspecting and repairing a video image file, an index file inspecting and repairing means (113) for inspecting and repairing the index file including the index information of the video file, and a recording means (111) for recording the video image file and the index file. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a video recording device and a video recording method, and more particularly to a video recording device and a video recording method for recording an MPEG2-encoded video on a recording medium such as a hard disk.
[0002]
[Prior art]
In recent years, devices that encode terrestrial TV broadcasts by MPEG2 and record them on a hard disk or DVD-RAM disk have been receiving attention. When video is recorded on these devices, it is generally recorded as a file. When a general-purpose OS such as Linux is used as an OS (Operating System), a file system (file management, writing, The part for controlling the reading) also uses the file system attached to the OS.
[0003]
In this case, if a power failure occurs during recording or the user accidentally unplugs the AC plug and a forced power off occurs, the file restoration function of the OS file system will be used at the next power on and OS startup. The working file is repaired, but in the worst case, the file system itself may be destroyed. In recent years, Linux has started adopting a journaling file system having a function of preventing inconsistency and destruction of a file system from sudden power-off.
[0004]
[Problems to be solved by the invention]
However, even when a journaling file system having a repair function is used as the file system in the above-described conventional technology, only the consistency of the file management area (I-node) is guaranteed, and the data written to the file itself is not guaranteed. Not guaranteed. This is because if the data itself is guaranteed, the efficiency such as the writing speed of the file system decreases.
[0005]
FIG. 7 shows an outline of data of a recording target file when a power failure occurs during recording. As shown in FIG. 7, of the length of the video data recorded from the start of recording to the occurrence of power interruption, that is, the file length indicated by the management area, the data is normal up to the middle of the file, but random near the end of the file. Data is written. This phenomenon prevents the inconsistency from occurring by duplicating the management area that manages the length of the file, etc., but the data of the file itself is written in the OS write buffer and the hard disk write. This is because the ejection of data included in the cache is performed later than the writing of the management area.
[0006]
In many cases, a video recording apparatus simultaneously writes a video file obtained by compressing an input video by MPEG2 and an index file storing a GOP (Group of Picture) position and the like in the video file. In this case, meaningless data exists at the end of both the video file and the index file. If these files are used for reproduction as they are, the meaningless data portion of the video file cannot be decoded, and there is a problem that a useless area on the recording medium is consumed. Further, if meaningless data exists at the end of the index file, an impossible GOP position is indicated, and there is a problem that reproduction may not be performed at all.
[0007]
The present invention solves these problems, and a video recording apparatus and a video recording apparatus capable of preventing unnecessary consumption of a recording capacity by a video file and an index file of the video file and a reproduction error of the file. It is to provide a method.
[0008]
[Means for Solving the Problems]
In order to solve the above problems and achieve the object, a video recording device and a video recording method of the present invention are configured as follows.
[0009]
(1) A video recording apparatus according to the present invention comprises: a video file inspection / repair unit for inspecting and restoring a video file; an index file inspection / repair unit for examining and restoring an index file including index information of the video file; Recording means for recording the video file and the index file.
[0010]
(2) The video recording method of the present invention performs inspection and restoration of a video file and an index file including index information of the video file, and records the video file and the index file.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present embodiment will be described with reference to the drawings.
[0012]
FIG. 1 is a diagram showing a schematic configuration of a video recording device according to the first embodiment of the present invention. The outline of the operation of the present apparatus is as follows.
[0013]
The system control unit 102 receives an instruction 101 from a user and outputs a control instruction 103 to each unit. Specifically, first, the system control unit 102 receives a video input selection instruction. Thereby, the system control unit 102 outputs the control instruction 103 to each unit, and switches the input video to either the video from the tuner or the video from the line input. Next, the system control unit 102 receives a recording start instruction. The system control unit 102 activates the MPEG2 encoder 110 and the recording control unit 111. The MPEG2 encoder unit 110 receives a signal selected from the tuner input or the line input, performs MPEG2 compression, and sends the signal to the subsequent stage. When the recording control unit 111 is activated, the index file 118 and the video file 117 are opened, and the respective file names are notified to the file system 120.
[0014]
FIG. 2 is a diagram showing an example of the data structure of the index file 118. The index file 118 includes index information of the video file 117. The index information is, for example, information indicating a GOP position. In the video file 117, MPEG2 compressed digital data output from the MPEG2 encoder unit 110 is stored. The recording control unit 111 receives the MPEG2 compressed data transmitted from the MPEG2 encoder 110, checks the MPEG2 header, and writes the GOP position from the file head into the index file 118 when detecting the GOP head. The GOP head may be detected by a notification from the MPEG2 encoder unit 110. The MPEG2 compressed data is written to the video file 117 regardless of whether the GOP head is detected. Each file writing is performed via the file system 120. This process is continued while the recording is continued.
[0015]
Finally, when receiving the instruction 101 from the user, that is, the recording stop instruction, the system control unit 102 stops encoding to the MPEG2 encoder unit 110 and stops processing to the recording control unit 111. Upon receiving the encoding stop instruction, the MPEG2 encoding unit 110 stops data transmission to the subsequent stage. Upon receiving the recording stop instruction, the recording control unit 111 closes the video file 117 and the index file 118.
[0016]
In the video recording apparatus according to the first embodiment, a restoration process is performed by the system control unit 102 at the time of startup, for example. FIG. 3 shows a schematic flowchart of the restoration process. The system control unit 102 extracts a set of the stored video file names and index file names of all recorded titles (ST101). Here, since the restoration of all the titles has not been completed (NO in ST102), a pair of the video file name and the index file name is extracted one by one (ST103), and the index file restoration unit 113, the mutual restoration unit 114, the video file The repair unit 115 is called in order (ST104, ST105, ST106). This process is performed for all pairs of the video file name and the index file name.
[0017]
First, the index restoration unit 113 is activated. FIG. 4 shows a processing flowchart of the index restoration unit 113. For example, it is assumed that the offset value from the head of the video file of each GOP in the index file is stored in 8 bytes. Each of these 8 bytes is called a record, and the value of each record in the index file is index [0], index [1],. . . . . , Index [N]. N indicates the total record length. The value of each record monotonically increases because the location of the GOP in the video file is stored in order. This is impossible when the value index [i + 1] of the next record is smaller than the value index [i] of a certain record. First, the index restoring unit 113 acquires the file size of the index file and substitutes it for fSize (ST201). Next, the remainder of fSize / 8 is obtained (ST202). If it is 0 (ST203, YES), the process proceeds to the next step without performing any operation. If it is not 0 (ST203, NO), the size of the index file is reduced by the remaining length (ST204). Next, 0 is assigned to the variable I (ST205), 8 bytes are read from the index file, and assigned to index [0] (ST206). Enter the loop from here. Eight bytes are read from the index file and assigned to index [I + 1] (ST207). If index [I] <index [I + 1] (ST208, YES), I is incremented by 1 (ST209). When I is larger than N-1 (ST211, NO), the process exits the loop and ends. Otherwise, the process returns to the beginning of the loop (ST207). If index [I] ≧ index [I + 1] holds (ST208, NO), it is determined that abnormal data has been written, the index file after index [I + 1] is truncated (ST210), and the restoration process ends. I do. The processing of the index restoration unit 113 guarantees that each record of the index file is monotonically increasing.
[0018]
Next, the mutual repair unit 114 is activated. FIG. 5 shows a processing flowchart of the mutual repair unit 114. In this embodiment, for simplicity, the length of each pack is fixed at 2048 bytes, and the length of the pack header is also fixed at 14 bytes. Further, it is assumed that a System Header always exists at the head pack of the GOP. In the case of this structure, it is possible to determine that the GOP is the head of the GOP if the data from the 15th byte to the 18th byte is 0x00, 0x00, 0x01, 0xbb (System Header start code). First, 0 is substituted for the variable I (ST301). Enter the loop from here. 8 bytes are read from the index file (ST302) and assigned to index [0]. Next, the video file is sought by index [0] from the top (ST303), 1024 bytes are read, and assigned to a buffer (ST304). If Buffer [14] == 0 and buffer [15] == 0 and buffer [16] == 1 and buffer [17] == 0xbb, it is determined as a normal GOP (ST305, YES), and I is increased by 1 (ST306). ). When I becomes N or more (ST307, NO), the process exits the loop and ends. Otherwise (ST307, YES), the process returns to the loop head (ST302). Buffer [14]! = 0 or buffer [15]! = 0 or buffer [16]! = 1 or buffer [17]! In the case of = 0xbb, it is determined to be an abnormal GOP (ST305, NO), the portion after index [I] in the video file is deleted (ST308), the record after the Ith in the index file is deleted (ST309), and the correction process is performed. To end.
[0019]
Finally, the video file restoration unit 115 is activated. In the video file recording unit, only the last GOP is checked, and a detailed check is made as to whether or not it conforms to the MPEG2 standard. The purpose of the video file restoration unit 115 is that the mutual restoration unit 114 checks only the top of the GOP, so that the validity of the GOP immediately before the last GOP can be guaranteed, but the top of the GOP exists for the last GOP. Can only be guaranteed. Therefore, the video file restoration unit 115 needs to check the last GOP. For example, it is determined whether the final GOP is a multiple of 2048 bytes (a multiple of the pack length). If the final GOP is not a multiple of the pack length, the remainder is discarded.
[0020]
When the power supply to the system is cut off due to a power failure or the like while recording is being performed on the video recording device, the video file and index file already recorded on the recording medium are restored, and the damaged part and the video file are deleted. The part where the inconsistency occurs between the index files and the incomplete GOP are removed. As a result, it is possible to save the title that was recorded before the power was turned off as much as possible. Further, since there is no inconsistency between the video file and the index file, no trouble occurs during reproduction. Also, at the time of startup, the restoration processing is performed on all the recorded titles, and this processing always keeps the consistency of all the titles.
[0021]
The format of the index file is not limited to the format described above. If the position of each GOP in the video file is stored in some form, the above-described restoration processing in the video recording device can be realized.
[0022]
The video recording apparatus described above detects that power has been lost during recording at the next start-up even if the power has been lost during the execution of recording. In this case, a file can be independently repaired and repaired by consistency of mutual relations, and abnormal data in the video file and the index file can be truncated to make the file playable normally.
[0023]
FIG. 6 is a diagram showing a schematic configuration of a video recording device according to the second embodiment of the present invention. An outline of the operation of the present apparatus will be described focusing on points different from the video recording apparatus shown in FIG.
[0024]
In this video recording apparatus, when the system control unit 102 receives a recording start instruction from the user, the system control unit 102 activates the MPEG2 encoder 110 and the recording control unit 111, and also activates the state recording unit 112. To the “Recording” information. The state recording unit 112 writes the “recording flag” in the recording medium 116 or the nonvolatile memory based on the “recording” information received from the system control unit 110 so that the information is not lost even when the power is turned off.
[0025]
Next, when the system control unit 102 receives a recording stop instruction from the user, the system control unit 102 notifies the status recording unit 112 of “recording stop” information. The state recording unit 112 determines that the recording has been normally completed only when receiving the “recording stop” notification from the system control unit 102, and clears the “recording flag” stored in the recording medium 116. As described above, the “recording” flag is ON only when recording is being performed in the system.
[0026]
If a power failure occurs or the user accidentally removes the power plug during the above-described recording state, the power supply to the entire system is cut off, and all the systems are stopped. Then, after the power is turned on for the first time and the system is started, the system control unit 102 inquires the state control unit 112 of the necessity of restoration. The system control unit 102 determines whether restoration is necessary based on the “recording flag” recorded in the recording medium 116 or the nonvolatile memory. If the "recording flag" is present, it is determined that an unexpected power interruption has occurred during the execution of recording, and a notification of the need for repair and a file name of the file to be repaired are sent to the system control unit 102. If the “recording flag” is cleared, the recording has been completed normally and there is no need for restoration, so that the system controller 102 is notified that restoration is unnecessary.
[0027]
When the system control unit 102 receives the notification of the need for repair, the system control unit 102 starts the file repair process only for the file to be repaired. The file restoration processing of the recording / reproducing apparatus shown in FIG. 6 is the same as the file restoration processing of the video recording / reproducing apparatus shown in FIG.
[0028]
With the video recording device of the second embodiment, the restoration process can be started only when necessary, and the system can be started quickly.
[0029]
It should be noted that the present invention is not limited to the above-described embodiment, and can be variously modified in an implementation stage without departing from the spirit of the invention. In addition, the embodiments may be implemented in appropriate combinations as much as possible, in which case the combined effects can be obtained. Further, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriate combinations of a plurality of disclosed constituent elements. For example, even if some components are deleted from all the components shown in the embodiment, the problem described in the column of the problem to be solved by the invention can be solved, and the effects described in the column of the effect of the invention can be solved. Is obtained, a configuration from which this configuration requirement is deleted can be extracted as an invention.
[0030]
【The invention's effect】
According to the present invention, it is possible to provide a video recording apparatus and a video recording method capable of preventing unnecessary consumption of a recording capacity by a video file and an index file of the video file and a reproduction error of the file.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a schematic configuration of a video recording device according to a first embodiment of the present invention.
FIG. 2 is a diagram illustrating an example of a data structure of an index file.
FIG. 3 is a flowchart illustrating an outline of a restoration process of a video file and an index file.
FIG. 4 is a flowchart illustrating an index file restoration process performed by an index file restoration unit.
FIG. 5 is a flowchart showing a process of repairing a video file and an index file by a mutual repair unit.
FIG. 6 is a block diagram illustrating a schematic configuration of a video recording device according to a second embodiment of the present invention.
FIG. 7 is a diagram showing an outline of data of a video file affected by a power-off during recording.
[Explanation of symbols]
102 system control unit 110 MPEG encoder 111 recording control unit 112 state recording unit 113 index file restoration unit 114 mutual restoration unit 115 video file restoration unit 116 recording medium 120 file system

Claims (6)

Video file inspection and repair means for inspecting and repairing video files;
Index file inspection and repair means for inspecting and repairing the index file including the index information of the video file,
Recording means for recording the video file and the index file;
A video recording device comprising: 2. The video recording apparatus according to claim 1, further comprising a mutual inspection and repair unit that performs mutual consistency inspection and repair of the video file and the index file. State recording means for recording the recording state of the video file and the index file by the recording means,
Control means for determining the necessity of restoration of the video file and the index file based on the recording state recorded by the state recording means and executing the restoration,
The video recording device according to claim 1, further comprising: Inspect and repair the video file and the index file containing the index information of this video file,
Recording the video file and the index file,
A video recording method, characterized in that: 5. The video recording method according to claim 4, wherein in addition to the inspection and restoration of the video file and the index file, a mutual consistency inspection and restoration of the video file and the index file are performed. When recording the video file and the index file, record the recording state of these files,
Determining the need for restoration of the video file and the index file based on the recorded recording state and causing the restoration to be performed;
7. The video recording method according to claim 5, wherein:

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