JP4274783B2 - Recording device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a recording apparatus and a recording method for decompressing and reproducing an image recorded by compression, and more particularly to a recording apparatus for preventing file destruction and information loss when the recording apparatus abnormally ends due to a power failure or the like. In place Related.
[0002]
[Prior art]
Conventionally, a surveillance system has a surveillance camera installed at a certain location, and monitors and reproduces the video of the location on the monitor in real time, accumulates the surveillance video in a recording / playback device, and plays back the recorded video as necessary. Like to do. A recording / playback apparatus that simultaneously plays back and searches while recording, stores all management information created on the recording medium in a physical memory that can be accessed at high speed, and performs recording while backing up to the recording medium at an arbitrary timing. However, in a recording / reproducing apparatus that records all management information on a physical memory that has only a limited address space, a magnetic disk that can be managed according to the capacity of the installed physical memory, There is a problem that the recording capacity of the optical disk is limited. Therefore, by installing a paging function, which is one method of virtual storage, in the recording / reproducing apparatus, management of a large-capacity recording medium using a small-capacity memory is realized.
[0003]
By the way, disk recording media such as a randomly accessible magnetic disk and magneto-optical disk have come to be used as storage media for recording and reproducing devices. With conventional tape media, if a power failure occurs during recording, the video up to the power failure is saved, but in the case of a disk recording medium configured for a computer, if the recording end process is not correct, There was a problem of losing all of the surveillance video up to the power failure.
Hereinafter, data recording on a disk recording medium configured for a computer will be described with reference to FIG. 15 (see, for example, Non-Patent Document 1).
[0004]
[Non-Patent Document 1]
File Allocation Table type file structure defined in JIS X 0605 standard.
[0005]
FIG. 15 is a diagram showing a file structure defined in the JIS X 0605 standard. In FIG. 15, the recording area of the disk recording medium includes a root directory 1001, a file allocation table 1002, and a cluster 1003.
The root directory 1001 holds the name of the file stored on the disk recording medium and the first cluster number of the file. The file allocation table 1002 holds connection information of the cluster 1003 in which the file is configured. The cluster 1003 is a minimum unit of recording / reproducing of a disk recording medium, and holds actual data.
[0006]
In the example shown in FIG. 15, the root directory 1001 indicates that a file named Data1 is stored on the disk recording medium from the cluster number 0002, and the file allocation table 1002 indicates that the Data1 is the cluster number 0002, the cluster number 0003, And that the data is configured in the order of the cluster number 0004. Therefore, the actual data of Data1 is stored in the areas of cluster number 0002, cluster number 0003, and cluster number 0004 of cluster 1003. Note that FFFF in the file allocation table 1002 is a cluster number indicating the final cluster of the file.
At the time of data recording, first, the file name and the leading cluster number are registered in the root directory 1001, and the actual data is recorded in each area of the cluster 1003 while updating the connection information of the cluster 1003 by the file allocation table 1002.
[0007]
By the way, the root directory 1001 and the file allocation table 1002 are fixed to the disk recording medium, and each area of the cluster 1003 uses an area of the disk recording medium other than the root directory 1001 and the file allocation table 1002.
If data is to be written to the file allocation table 1002 and each area of the cluster 1003 during data recording, the cluster connection information in the file allocation table 1002 needs to be updated each time the cluster 1003 is written. It becomes necessary to seek the writing head, and the writing speed becomes extremely slow.
[0008]
Therefore, data is written into the cluster 1003 while updating the information in the file allocation table 1002 in the memory, and the information in the file allocation table 1002 is reflected on the disk recording medium at the time of data recording end processing or periodically. The method is adopted.
Conventionally, a file recovery method as shown in FIG. 16 is known (see, for example, Patent Document 1).
[0009]
[Patent Document 1]
JP-A-2000-40023 (5th page, paragraphs 19 to 20, FIG. 1).
[0010]
The conventional file recovery system shown in FIG. 16 includes a process 1101 for accessing a file, an external storage device 1102, and a file management unit 1211. In the external storage device 1102, an update log 1103 that is a record of the recording operation of the file 1107, a backup update log 1104 that is a backup storage area of the update log 1103, and a hash that stores a repair directory according to a hash function It includes a table 1105, a file management block 1106 for managing files for each file, and a directory 1108 that summarizes file names and related information. The file management unit 1111 includes a file access unit 1112 that accesses the file 1107 according to the application program of the process 1101, a file restoration unit 1113 that includes a program that works on the external storage device 1102 when the file 1107 is restored, and a hash function at a predetermined time. And a hash table creating means 1114 for forming a table according to FIG.
[0011]
When the external storage device 1102 starts to be used, the update log 1103 is copied to the backup update log 1104, and the contents updated from the backup update log 1104 are registered in the hash table 1105. Thereafter, when there is an access to the file 1107, the hash table 1105 is first searched. If the file is to be repaired, the file 1107 is accessed after being repaired.
As described above, according to the conventional file system and file recovery method, file recovery processing is performed based on the update log 1103 recorded in the external storage device 1102, so that the active file is destroyed or data is lost when a power failure occurs. The loss of will never happen.
[0012]
[Problems to be solved by the invention]
However, if a power failure occurs before the recording end process is performed in the conventional recording on the disk recording medium, the file allocation table 1002 of the disk recording medium is not updated, so the power failure occurs from the start of recording. Up to now, although the data is recorded in the cluster 1003, the connection information of the file allocation table 1002 indicating the connection information of the cluster 1003 is lost, and there is a problem that the file is destroyed and the data is lost. It was.
[0013]
In addition, by periodically updating the file allocation table of the disk recording medium, it is possible to prevent the loss of data recorded from the start of recording to immediately before the power failure. Since it was necessary to repair the connection information of the cluster, there was a problem that the transition to the recording start state was delayed after recovery from abnormal termination.
[0014]
The present invention has been made in order to solve the above-described conventional problems. When information recording is abnormally terminated due to a power failure or the like during information recording on a disk recording medium, the file is destroyed and the information is lost. Recording device that can transition to a recording startable state in a short time after recovery from an abnormal state. Place It is to provide.
[0015]
[Means for Solving the Problems]
The recording method according to the present invention records input video / audio data on a recording medium, creates hierarchical file management information for managing the video / audio data every time the video / audio data is recorded on the recording medium, and stores it in a memory And assigning a page writing priority level according to the hierarchical level of the hierarchical file management information stored and updated in the memory, and recording the hierarchical file management information in the order of the assigned page writing priority level. It has the structure of having each process recorded on a medium. With this configuration, even if an abnormal termination of the recording device occurs due to a power failure or the like during video / audio data recording, file management is performed from the start of recording to immediately before the power failure without performing file repair processing after recovery from the abnormal state. Information can be reproduced from the recording medium, and the file management information lost from the memory due to power failure can be guaranteed by the recording medium.
[0016]
The recording method according to the present invention includes a step of determining a write timing of the hierarchical file management information based on a total frame rate of the hierarchical file management information being recorded on the recording medium. ing. With this configuration, hierarchical file management information can be recorded efficiently, and the number of data lost when the power supply is abnormal can be minimized.
[0017]
In the recording method of the present invention, the step of recording the hierarchical file management information on the recording medium is performed when the recording of the hierarchical file management information on the recording medium is completed and the video / audio file is closed. The file management information includes a step of writing a page including video / audio data management information and indirect block information to the recording medium. With this configuration, even in an operation state where a large number of video / audio files with a small number of video / audio data are created at an arbitrary time, the video / audio data management information and the indirect block information are written to the recording medium when the video / audio file is closed. Since the file management information in the memory can be erased and the number of file management information to be held in the memory can be suppressed, the memory usage capacity can be reduced.
[0018]
The recording apparatus according to the present invention creates a recording medium for recording input video / audio data and hierarchical file management information for managing the video / audio data every time the video / audio data is recorded on the recording medium. A file management means for storing, and a page write priority level is assigned according to the hierarchy level of the hierarchical file management information stored and updated in the memory, and the hierarchical file is in order of the assigned page write priority level. And a memory management unit that records management information on the recording medium. With this configuration, even if an abnormal termination of the recording device occurs due to a power failure or the like during video / audio data recording, file management is performed from the start of recording to immediately before the power failure without performing file repair processing after recovery from the abnormal state. Information can be reproduced from the recording medium, and the file management information lost from the memory due to power failure can be guaranteed by the recording medium.
[0019]
The recording apparatus according to the present invention includes a page control unit that determines a write timing of the hierarchical file management information based on a total frame rate of the hierarchical file management information being recorded on the recording medium. Have. With this configuration, hierarchical file management information can be recorded efficiently, and the number of data lost when the power supply is abnormal can be minimized.
[0020]
In the recording apparatus according to the present invention, the memory management unit includes video / audio data management of the hierarchical file management information when the recording of the hierarchical file management information to the recording medium is completed and the video / audio file is closed. A page including information and indirect block information is written to the recording medium. With this configuration, even in an operation state where a large number of video / audio files with a small number of video / audio data are created at an arbitrary time, the video / audio data management information and the indirect block information are written to the recording medium when the video / audio file is closed. Since the file management information in the memory can be erased and the number of file management information to be held in the memory can be suppressed, the memory usage capacity can be reduced.
[0021]
The program according to the present invention records input video / audio data on a recording medium in a computer and creates hierarchical file management information for managing the video / audio data each time the video / audio data is recorded on the recording medium. And assigning a page writing priority level according to the hierarchical level of the hierarchical file management information stored and updated in the memory, and the hierarchical file management information in order of the assigned page writing priority level. Each of the functions for recording on the recording medium is realized. With this configuration, even if an abnormal termination of the recording device occurs due to a power failure or the like during video / audio data recording, file management is performed from the start of recording to immediately before the power failure without performing file repair processing after recovery from the abnormal state. Information can be reproduced from the recording medium, and the file management information lost from the memory due to power failure can be guaranteed by the recording medium.
[0022]
The program according to the present invention is configured to cause a computer to realize a function of determining a write timing of the hierarchical file management information based on a total frame rate of the hierarchical file management information being recorded on the recording medium. have. With this configuration, hierarchical file management information can be recorded efficiently, and the number of data lost when the power supply is abnormal can be minimized.
[0023]
In the program according to the present invention, the function of recording the hierarchical file management information on the recording medium is performed when the recording of the hierarchical file management information on the recording medium is completed and the video / audio file is closed on the computer. The hierarchical file management information includes a function of realizing a function of writing a page including video / audio data management information and indirect block information to the recording medium. With this configuration, even in an operation state where a large number of video and audio files with a small number of video and audio data are created at an arbitrary time, the video and audio data management information and indirect block information are written to the recording medium when the video and audio files are closed Since the file management information in the memory can be erased and the number of file management information to be held in the memory can be suppressed, the memory usage capacity can be reduced.
[0024]
A recording medium according to the present invention has a configuration in which the program according to any one of claims 7 to 9 is recorded. With this configuration, by transferring the program according to any one of claims 7 to 9 to another computer using a recording medium, the recording method of the present invention can be realized and the recording apparatus can be realized even at the destination computer. It will be possible.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the first and second embodiments of the present invention will be described in detail with reference to the accompanying drawings.
(First embodiment)
First, the configuration of the recording apparatus according to the first embodiment of the present invention will be described in detail with reference to FIGS. In FIG. 1, a recording apparatus 10 includes a video input unit 11 that converts an input video signal into digital, an audio input unit 12 that converts an input audio signal into digital, a video input unit 11 and an audio input unit 12. Encoding means 13 for encoding digital data from the image data to generate video / audio data, image memory 14 for temporarily storing a plurality of video / audio data, and video / audio data generated by the encoding means 13 for image memory 14 The image memory control means 15 for controlling the transfer to the recording medium 16 or writing to the recording medium 16, the recording medium 16 for recording the video / audio data, and creating a hierarchical file structure each time the video / audio data is recorded on the recording medium, or A file that stores an updated, created, or updated hierarchical file structure in a corresponding page in the memory 22. And a part of the hierarchical file structure (directory file 102, indirect block file 103, video / audio block file 104, etc.) recorded on the recording medium 16 in units of pages. And a memory management means 23 having a page table including information relating to information transfer of file management information between the memory 22 and the recording medium 16 and controlling access to the pages stored in the memory 22; The page control means 24 for instructing the memory management means 23 to write the updated page in the memory 22 to the recording medium 16 and the file management means 21 in conjunction with the recording medium 16, the encoding means 13 and the decoding means 19 The file structure management unit 20 that controls the video and audio data recorded on the recording medium 16 It comprises decoding means 30 for separating image and audio digital data, video output means 31 for converting video digital data into video signals, and audio output means 32 for converting audio digital data into audio signals. Yes.
[0026]
The page control unit 24 requests the file management unit 21 to acquire the total frame rate of the video / audio file being recorded, and based on the total frame rate acquired from the file management unit 21, the updated page in the memory 22. The interval or timing for instructing to write the file management information to the recording medium 16 is determined (described in the second embodiment). The recording of the file management information in the memory 22 to the recording medium 16 may be designated at any time, for example, when a page is updated. By finely setting the file management information, the file management information at the time of recovery after a power failure, etc. It can guarantee its existence.
The recording medium 16 is a recording device capable of random access, such as a hard disk (HDD), and is composed of one or a plurality of devices. In addition, the video / audio data recorded on the recording medium 16 has been subjected to intra-frame compression such as JPEG or inter-frame compression such as MPEG.
[0027]
Next, the configuration of the file structure (not including actual information) of the recording medium 16 of the recording apparatus according to the present embodiment will be described with reference to FIG.
In FIG. 2, the file structure of the recording medium 16 includes a volume management file 101, a directory file 102, and ,while It is composed of a contact block file 103 and a video / audio block file 104.
[0028]
The volume management file 101 shown in FIG. 2 is composed of a free directory entry number, a free indirect block entry number, and a free video / audio block entry number. The free directory entry number contains the first free entry number of the directory file 102. In the example of FIG. 2, 1 is recorded, indicating that the directory entry 1 is the first free entry in the directory file 102. In the free indirect block entry number, the top free entry number of the indirect block file 103 is recorded. In the example of FIG. 2, 3 is recorded, and the indirect block entry 3 is the top free entry of the indirect block file 103. Is shown. In the empty video / audio block entry number, the leading empty entry number in the video / audio block file 104 is recorded. In the example of FIG. 2, 4 is recorded, and the video / audio block entry 4 is the top of the video / audio block file 104. Indicates that the entry is empty. In this embodiment, the directory entry 102, the indirect block file 103, and the video / audio block file 104 are used in order from the top entry. That is, at the time of data recording, an entry to be used is determined based on the empty directory entry number, empty indirect block entry number, and empty video / audio block entry number recorded in the volume management file 101.
[0029]
The directory file 102 includes a plurality of directory entries, and each directory entry includes a name of a video / audio file, a time stamp, a double indirect block pointer, and the number of video / audio data.
A double indirect block pointer records a double indirect block number, and a double indirect block records one or more indirect block entry numbers.
In FIG. 2, three indirect pointers are recorded in the double indirect block (indirect block entry 0), 1 is recorded in the first pointer, and indirect block entry 1 is an indirect block. 2 is recorded in the second pointer, indicating that indirect block entry 2 is an indirect block. The FFFF of the third pointer indicates that the indirect block following the indirect block entry 2 does not exist in the file “AV1”.
[0030]
In the number of video / audio data, the number of video / audio data recorded in the corresponding video / audio file is recorded. In the example of FIG. 2, 4 is recorded, indicating that 4 video / audio data are recorded in the video / audio file “AV1”. The indirect block file 103 is composed of a plurality of indirect block entries, and each indirect block entry is composed of a plurality of indirect pointers or direct pointers. An indirect block entry number is recorded in the indirect pointer, and a direct pointer (management value) indicating the recording position and data size of the video / audio data recorded on the recording medium 16 is recorded in the indirect block. Are accessed directly). In the example shown in FIG. 2, three direct pointers are recorded in each indirect block.
[0031]
In the direct pointer, an entry number of the video / audio block file 104 for managing the recording position and data size of the video / audio data recorded on the recording medium 16 is recorded. In the example shown in FIG. 2, 0 is recorded in the first pointer of the indirect block entry 1, and the recording position and data size of the first video / audio data constituting the video / audio file are recorded in the video / audio block entry 0. 1 is recorded in the second pointer, and the recording position and data size of the second video / audio data constituting the video / audio file are recorded in the video / audio block entry 1 The third pointer indicates that 2 is recorded, and that the recording position and data size of the third video / audio data constituting the video / audio file are recorded in the video / audio block entry 2; In the first pointer of the block entry 2, 3 is recorded, and the fourth video constituting the video / audio file is stored in the video / audio block entry 3. Indicating that the recording position and the data size of the voice data is recorded. The second pointer and the third pointer FFFF of the indirect block entry 2 indicate that the video / audio data indicated by the video / audio block entry 4 is the final data of the video / audio file “AV1”.
[0032]
The video / audio block file 104 includes a plurality of video / audio block entries, and each video / audio block entry includes a recording position and a data size. In the example of FIG. 2, 0 and 10 are recorded in the recording position and data size of the video / audio block entry 0, indicating that the video / audio data is recorded at that position.
[0033]
Next, the data arrangement of the file structure of the recording medium 16 of the recording apparatus according to the present embodiment will be described with reference to FIG.
In the example shown in FIG. 3, the volume management file 101, the directory file 102, the indirect block file 103, and the video / audio block file 104 are arranged at physically continuous positions on the recording medium 16. In the data area 105, video / audio data is recorded.
In the present embodiment, an example is shown in which the directory file 102, the indirect block file 103, and the video / audio block file 104 on the recording medium 16 are managed in virtual storage (paging). An area on the recording medium 16 constituted by the directory file 102, the indirect block file 103, and the video / audio block file 104 is referred to as a page management area 200. The page management area 200 is divided into page units, and numbers consecutive from the first page are assigned as page numbers and used as virtual storage numbers.
[0034]
In the hierarchical file structure shown in the example of FIG. 3, when reproducing the audio / video data recorded in the data area 105 of the recording medium 16, the double indirect block pointer recorded in the directory entry (for example, 0000) is used. Acquire the recording position and size of the video / audio data to be played back by following three pieces of management data (double indirect block entry 0, indirect block entries 1 and 2, and video / audio block entries 0 to 3). can do.
In the example of FIG. 3, the volume management file 101, the directory file 102, the indirect block file 103, and the video / audio block file 104 are physically arranged continuously, but can also be distributed.
[0035]
In the example of FIG. 3, page numbers 0 to 5 are assigned to each page constituting the directory file 102, and page numbers 6 to 1FFF are assigned to each page constituting the indirect block file 103. Assigned. Also, audio / video block Each page constituting the file 104 has a page number 2000 to a page number 2FF. F is Assigned.
[0036]
FIG. 4 is a diagram showing a state where the address space of the memory 22 is divided into page frames. A page frame refers to a unit corresponding to a page in the memory 22, and the size of the page and the page frame is always the same.
In FIG. 4, there are ten page frames on the memory 22, and pages on the recording medium 16 are loaded into the page frames on the memory 22 as necessary during data recording / reproduction.
[0037]
Next, the data structure of the page table 40 in the memory management unit 23 of the recording apparatus according to the present embodiment will be described with reference to FIG.
In the page table 40, one page entry is assigned to each page frame (FIG. 4) in the memory 22. In the example of FIG. 5, the page table 40 includes 10 page entries (page entries 0 to 9), and information regarding the page loaded in the page frame 0 is recorded in the page entry 0 in the page table 40. It has a configuration.
[0038]
The page entry (0 to 9) includes a page number part 41, an update flag part 42, and a page writing priority level part 43.
In the page number section 41, the page number of the page loaded in the corresponding page frame on the memory 22 is recorded. In the example of FIG. 5, 0 is recorded in the page number part 41 of the page entry 0, and page 0 on the page management area 200 (FIG. 3) of the recording medium 16 is loaded into the page frame 0 on the memory 22. It shows that. 7 is recorded in the page number portion 41 of the page entry 1, indicating that the page 7 on the page management area 200 is loaded into the page frame 1 on the memory 22. 8 is recorded in the page number portion 41 of the page entry 2, indicating that the page 8 on the page management area 200 is loaded into the page frame 2 on the memory 22. 2000 is recorded in the page number portion 41 of the page entry 3, indicating that the page 2000 on the page management area 200 is loaded into the page frame 3 on the memory 22. 1 is recorded in the page number portion 41 of the page entry 4, indicating that page 1 on the page management area 200 is loaded into the page frame 4 on the memory 22. Note that FFFF in the page number portion 41 indicates that the page does not exist in the corresponding page frame and is in an empty state.
[0039]
The update flag section 42 records that data has been updated for the page loaded on the memory 22. That is, when a page is loaded into a page frame on the memory 22, the update flag unit 42 is cleared as an initial state, marked when the page is updated, and the updated page is written to the recording medium 16. When cleared, it is cleared. A mark (M) indicating data update is recorded in the update flag section 42 of the page entries 0, 1, 2, and 3, and the pages 0, 7, and 3 stored in the page frames 0, 1, 2, and 3 are recorded. 8 and 2000 indicate that the contents have been updated.
[0040]
The page writing priority level section 43 records the page writing priority level assigned to the directory file 102, the indirect block file 103, and the video / audio block file 104. That is, when a page is loaded into a page frame on the memory 22, the page write priority level is recorded according to the file type to which the page belongs, and is cleared when the page frame is empty. In this embodiment, page write priority levels 1, 2, and 3 are assigned to the directory file 102, the indirect block file, and the video / audio block file. In the example of FIG. 5, 1 is recorded in the page writing priority level of page entries 0 and 4, which means that pages 0 and 1 on the page management area 200 are pages belonging to the directory file 102. Is shown. 2 is recorded in the page writing priority level 43 of the page entries 1 and 2, indicating that the pages 7 and 8 on the page management area 200 are pages belonging to the indirect block file 103. 3 is recorded in the page writing priority level of the page entry 3, indicating that the page 2000 on the page management area 200 is a page belonging to the video / audio block file 104.
[0041]
Next, with reference to FIG. 2 and FIG. 6 to FIG. 11, the operation of recording the video / audio data input to the recording apparatus in the first embodiment of the present invention will be described.
In the flowchart shown in FIG. 6, when a video signal or an audio signal is input, the video input means 11 and the audio input means 12 convert the input information into digital data, and the encoding means 13 encodes the video and audio data. Generate. The image memory control means 15 stores the video / audio data generated by the encoding means 13 in the image memory 14 and instructs the file management means 21 to write to the recording medium 16. In response to the write instruction from the image memory control means 15, the file management means 21 records the video / audio data on the recording medium 16 (step S101).
[0042]
The file management means 21 is a video / audio serving as a storage destination of information (recording position, data size) related to the video / audio data recorded on the recording medium 16 based on the empty video / audio block number recorded in the volume management file 101. Determine the block entry. In the example of FIG. 2, 4 is recorded in the empty video / audio block entry of the volume management file 101, and the file management means 21 stores information on video / audio data in the video / audio block entry 4 of the video / audio block file 104 ( (Recording position, data size) are stored.
[0043]
When the update of the video / audio block entry is completed, the file management unit 21 records the video / audio block entry number in the direct pointer in the indirect block 103. In the example of FIG. 2, 0004 is recorded in the second direct pointer of the indirect block entry 2. When all the direct pointers in the indirect block are in use (when there is no direct pointer in which FFFF is recorded), the free indirect block is acquired based on the free indirect block entry number of the volume management file 101. The video / audio block entry number is recorded in the direct pointer of the free indirect block, and the indirect block entry number of the acquired indirect block is recorded in the indirect pointer of the double indirect block.
When the update of the indirect block is completed, the number of video / audio data in the directory entry (0000 in FIG. 2) is updated. In the example of FIG. 2, the number of video / audio data of the directory entry 0 is updated to 5.
When empty entries of the directory file 102, the indirect block file 103, and the audio / video block file 104 are used, the empty entry numbers of the volume management file 101 are updated (step S102).
[0044]
The file management means 21 instructs the memory management means 23 to convert a virtual address into a physical address in order to store the created or updated file management information (directory entry, indirect block entry and video / audio block entry) in the memory 22. . Here, the virtual address indicates a recording position on the management information area 200 of the directory entry, the indirect block entry, and the video / audio block entry. As shown in FIG. 9, the virtual address 50 includes a page number part and an in-page address (step S103).
[0045]
When the memory management unit 23 is instructed by the file management unit 21 to convert the virtual address to a physical address, the memory management unit 23 refers to the page number section 41 in the page table 40 (FIG. 5), and the virtual address 50 (FIG. It is searched whether there is a page number (page entry) that matches the page number of () (step S104). If the corresponding page does not exist, page-in processing (described later) is performed (step S105). , If the corresponding page exists, the memory management unit 23 performs address conversion from the virtual address to the physical address for the memory 22 (step S106). When the address conversion is completed, the memory management unit 23 returns the converted physical address to the file management unit 21.
[0046]
Here, an example of address conversion from a virtual address to a physical address will be described with reference to FIG.
In FIG. 10, first, the virtual address 50 is a page number 000. 7 And in-page address α. The memory management unit 23 searches the page entry of the page table including the page number 0007, and when the corresponding page entry 1 is searched, replaces the page number 0007 of the virtual address 50 with the page frame number 1 to generate a physical address. .
[0047]
Returning to step 107 in FIG. 6, the file management means 21 stores the directory entry, the indirect block entry, and the video / audio block entry at predetermined positions in the memory 22 based on the physical address returned from the memory management means 23. The memory management means 23 is notified that the page has been updated (step S107). That is, only the management information created by the file management means 21 is stored in the memory 22.
In response to the page update notification from the file management unit 21, the memory management unit 23 marks the update flag part 42 of the corresponding page entry in the page table 40 (step S108).
[0048]
Next, a page-in operation of information from the recording medium 16 of the recording apparatus to the memory 22 according to the first embodiment of the present invention will be described with reference to the flowchart of FIG.
When reading of a page from the recording medium 16 is instructed, the memory management unit 23 determines whether there is an empty page frame on the memory 22 and whether the page number part 41 of each page entry in the page table 40 is an empty page. Judgment is made by checking whether the frame is an FFFF indicating a frame (step S201). If there is no empty page frame, the process proceeds to page-out processing (step S202). If there is an empty page frame, an empty page frame as a page transfer destination is acquired (step S203).
[0049]
The memory management unit 23 reads the corresponding page from the recording medium 16 and stores it in the acquired page frame. At this time, a group of pages including the corresponding page may be prefetched collectively. Here, prefetching means loading a page to be referred to in the future onto the memory 22 in advance (step S204).
The memory management unit 23 records the page number of the corresponding page in the page number portion 41 of the corresponding page entry of the page table 40 (step S205), and the file type to which the page belongs based on the page number of the corresponding page. And the page write priority level assigned to each file type is recorded in the page write priority level section 43 of the page entry (step S206).
[0050]
Next, the information page-out operation from the memory 22 of the recording apparatus to the recording medium 16 according to the first embodiment of the present invention will be described with reference to the flowchart of FIG.
The memory management unit 23 selects a page to be deleted from the pages stored in the page frame in the memory 22 (step S301). The memory management unit 23 determines whether or not the selected page has been updated by referring to the update flag part 42 of the corresponding entry in the page table 40 (step S302). If it is an unupdated page, the process proceeds to step 306. If it is an updated page, the process proceeds to step S303, where the corresponding page is recorded at a predetermined position on the recording medium 16 by the verify recording operation, and the page is recorded on the recording medium 16 based on the response result by the verify recording operation. It is determined whether or not normal termination has been completed (step S304). When the page is normally recorded on the recording medium 16, the process proceeds to step S305. When the page is not normally recorded on the recording medium 16, the memory management unit 23 notifies the file management unit 21 that a failure has occurred in the recording medium 16 that is recording data. In response to the notification from the management means 23, data recording to the recording medium 16 where the failure has occurred is stopped (step S308).
[0051]
The memory management unit 23 clears the update flag part 42 of the corresponding entry of the page table 40 (step S305), records FFFF in the page number part 41 of the corresponding page entry of the page table 40, and stores the corresponding page frame. An empty page frame is set (step S306).
The memory management unit 23 clears the page writing priority level part 43 of the corresponding entry in the page table 40 (step S307).
[0052]
Next, an update page write operation in the recording apparatus according to the first embodiment of the present invention will be described with reference to the flowchart of FIG.
When the memory management unit 23 receives an update page write request from the page control unit 24, the memory management unit 23 refers to the update flag section 42 and the page write priority level 43 of each page entry of the page table 40, and stores it in the corresponding page frame. It is determined whether or not the page being updated is an update page of page writing priority level 3 (step S401).
[0053]
If it is not an update page at page write priority level 3, the process proceeds to step S405. If it is an update page at page write priority level 3, the process proceeds to step S402, and the corresponding page is verified at a predetermined position on the recording medium 16. It is recorded by the operation, and based on the response result by the verify recording operation, it is determined whether or not the page recording on the recording medium 16 has been normally completed (step S403). Therefore, when the page is normally recorded on the recording medium 16, the process proceeds to step S404. If the page is not normally recorded on the recording medium 16, the process proceeds to step S411, and the memory management means 23 notifies the file management means 21 that a failure has occurred in the recording medium 16 that is recording data, and the file The management unit 21 receives the notification from the memory management unit 23 and stops data recording on the recording medium 16 where the failure has occurred.
[0054]
In step S404, the update flag part 42 of the corresponding page entry in the page table 40 is cleared (step S404).
The memory management unit 23 determines whether or not all the updated pages with the page writing priority level 3 have been recorded on the recording medium 16 (step S405). If the recording has not been completed, the process proceeds to step S401. When the recording is completed, the process proceeds to step S406, the update flag section 42 and the page writing priority level 43 of each page entry in the page table 40 are referred to, and the page stored in the corresponding page frame is written to the page. It is determined whether or not the page is a priority level 2 update page (step S406).
[0055]
If it is not an updated page of page writing priority level 2, the process proceeds to step S407. If it is an updated page of page write priority level 2, the process proceeds to step 402, where the corresponding page is recorded at a predetermined position on the recording medium 16 by a verify operation, and based on the response result by the verify recording operation, the recording medium It is determined whether or not the page recording to 16 has been completed normally (step S403). If the page is normally recorded on the recording medium 16, the process proceeds to step S404. When the page is not normally recorded on the recording medium 16, the memory management unit 23 notifies the file management unit 21 that a failure has occurred in the recording medium 16 that is recording data, and the file management unit 21 performs memory management. In response to the notification from the means 23, data recording to the recording medium 16 where the failure has occurred is stopped (step S411).
[0056]
In step S404, the update flag part 42 of the corresponding page entry in the page table 40 is cleared, and the process proceeds to step S407 (step S404).
Therefore, the memory management unit 23 determines whether or not all the updated pages with the page writing priority level 2 have been recorded on the recording medium 16 (step S407). If the recording has not been completed, the process proceeds to step S406. When the recording is completed, the process proceeds to step S408, and the update flag part 42 and the page writing priority level 43 of each page entry of the page table 40 are referred to, and the page stored in the corresponding page frame is set to the page writing priority. It is determined whether or not the page is a level 1 update page (step S408).
[0057]
If it is not an update page of page writing priority level 1, the process proceeds to step S409. If it is an update page of page writing priority level 1, the process proceeds to step 402, where the corresponding page is recorded at a predetermined position on the recording medium 16 by a verify recording operation, and recording is performed based on the response result by the verify recording operation. It is determined whether or not the page recording on the medium 16 has been normally completed (step S403). If the page is normally recorded on the recording medium 16, the process proceeds to step S404. When the page is not normally recorded on the recording medium 16, the memory management unit 23 notifies the file management unit 21 that a failure has occurred in the recording medium 16 that is recording data, and the file management unit 21 performs memory management. In response to the notification from the means 23, data recording to the recording medium 16 where the failure has occurred is stopped (step S411).
[0058]
In step S404, the update flag part 42 of the corresponding page entry in the page table 40 is cleared, and the process proceeds to step S409 (step S404).
The memory management unit 23 determines whether or not all the updated pages with the page writing priority level 1 have been recorded on the recording medium 16 (step S409). If the recording has not been completed, the process proceeds to step S408. When the recording is completed, the process proceeds to step S410, and the volume management file 101 is recorded at a predetermined position on the recording medium 16 (step S410).
[0059]
As a result, the update page is recorded in order from the update page corresponding to the lowest level of the hierarchical file structure when the update page is written, and the page writing process is immediately stopped when a failure occurs in the recording medium 16 during the update page write. Thus, the file structure on the recording medium 16 can be prevented from being destroyed, so that the recorded file can be reproduced without performing file repair.
[0060]
Next, a file structure different from that shown in FIG. 1 of the recording apparatus according to the first embodiment of the present invention will be described in detail with reference to FIG.
FIG. 13 is a diagram showing a file structure when one new video / audio data is recorded in the video / audio file “AV1” shown in FIG. Here, it is assumed that the hierarchical file structure shown in FIG. 2 is recorded on the recording medium 16.
In FIG. 13, 5 is recorded as the number of video / audio data in the directory entry 0, indicating that five video / audio data are recorded in the video / audio file “AV1”. 4 is recorded in the second direct pointer of the indirect block (indirect block entry 2), and the recording position and data size of the fifth video / audio data forming the video / audio file are recorded in the video / audio block entry 4. Indicates that 5 is recorded in the empty video / audio block entry number of the volume management file 101.
[0061]
Here, in the example of FIG. 13, when an abnormal end occurs before the update page writing process on the recording medium 16 is completed, the video newly recorded on the recording medium 16 stored in the memory 22. Although the entry information regarding the audio data (the second pointer of the indirect block entry 2 and the video / audio block entry 4) is lost, the hierarchical file structure shown in FIG. At the start of energization, the entry information recorded until immediately before the page writing process can be reproduced without performing the file restoration process.
[0062]
As described above, according to the first embodiment of the present invention, a hierarchical file structure is created or updated each time video / audio data is recorded on the recording medium 16, and the hierarchical file structure created or updated is created. Is stored in the corresponding page on the memory 22 and has a page table for storing information relating to the data transfer of the hierarchical file structure between the memory 22 and the recording medium 16. And a memory management unit 23 that controls access to a page, and when a page write priority level is assigned in advance for each layer of the hierarchical file structure and an updated page is recorded on the recording medium 16. Even if an abnormal termination such as a power failure occurs during data recording by recording in order from the page with the highest page writing priority level, Since the file information has already been recorded on the recording medium 16 when the power is resumed, the file information lost from the memory 22 due to the power supply abnormality is not subjected to the file information repair process after the power supply abnormality is terminated, and immediately before the power failure. Since the data recorded so far can be reproduced, the file information lost from the memory 22 due to the power supply abnormality can be guaranteed, and the recording can be resumed quickly after the abnormality is resolved.
[0063]
(Second Embodiment)
Next, a recording apparatus according to the second embodiment of the present invention will be described in detail with reference to FIG. In the present embodiment, the page control unit 24 performs recording. Medium The difference from the first embodiment is that the setting of the page writing interval for 16 is controlled.
That is, the page control unit 24 records Medium 16 requests the file management means 21 to obtain the total frame rate of the file management information during the recording operation, and based on the total frame rate obtained from the file management means 21, the recording medium of the update page in the memory 22 The interval or timing for instructing writing to 16 is determined.
FIG. 12 shows an example of an interval or timing for instructing writing of an updated page to the recording medium 16, and recording is performed at 11:00 to 11:59 at a total of 30 frames / second, during this interval of 40 seconds. 10:00 to 12:59 indicates that the recording operation is performed at a total of 60 frames / second, and during this time, the page writing process is performed at intervals of 20 seconds. -13: 59 indicates that the recording operation is performed at a total of 120 frames / second, and the page writing process is performed at intervals of 10 seconds.
As described above, in the present embodiment, by setting the page writing interval in advance and changing the page writing interval according to the time, the maximum number of data lost due to abnormal termination of the recording apparatus can be obtained. At most, for example, it can be guaranteed that there are 1,200 frames, and the number of lost data can be minimized.
[0064]
(Third embodiment)
Next, a recording apparatus according to the third embodiment of the present invention will be described in detail with reference to FIG.
The recording device in the present embodiment is different from the first embodiment described above in that when the video / audio file is closed (closed), the memory management means 23 includes the video / audio of the hierarchical file management information. The difference is that a page of hierarchical file management information including a block entry and an indirect block entry is written to the recording medium 16.
[0065]
The operation of the recording apparatus according to the third embodiment of the present invention will be described with reference to the flowchart shown in FIG.
First, the file management means 21 requests the memory management means 23 to write the video / audio block entry assigned to the video / audio file to the recording medium 16. In response to the video / audio block entry write request from the file management unit 21, the memory management unit 23 receives the memory 2 2 The page including the file management means is acquired from the pages stored therein. (Step S501).
[0066]
The memory management unit 21 records the corresponding page at a predetermined position on the recording medium 16 by the verify recording operation (step S502), and based on the response result by the verify recording operation, the page recording on the recording medium 16 is normal. It is determined whether or not the processing has been completed (step S503). If the page is normally recorded on the recording medium 16, the process proceeds to step S504. When the page is not normally recorded on the recording medium 16, the memory management unit 23 notifies the file management unit 21 that a failure has occurred in the recording medium 16 that is recording data, and the file management unit 21 performs memory management. In response to the notification from the means 23, data recording to the recording medium 16 where the failure has occurred is stopped (step S506).
[0067]
In step S504, the memory management unit 23 clears the update flag part 42 of the corresponding entry in the page table 40 (step S504).
It is determined whether or not writing to the recording medium 16 has been completed for all of the video / audio blocks assigned to the video / audio file. If the writing is completed as a result of the determination, the memory management unit 23 notifies the file management unit 21 that the writing of the video / audio block to the recording medium is completed, and the process proceeds to step S508. If the writing has not been completed, the process proceeds to step S501 (step S507).
[0068]
The file management means 21 requests the memory management means 23 to write the indirect block entry assigned to the video / audio file to the recording medium 16. The memory management unit 23 receives the indirect block entry write request from the file management unit 21, and acquires a page including the indirect block entry from the pages held in the memory 22 (step S508).
The memory management unit 21 records the corresponding page at a predetermined position on the recording medium 16 by the verify recording operation (step S502), and based on the response result by the verify recording operation, the page recording on the recording medium 16 is normal. It is determined whether or not the processing has been completed (step S503). When the page is normally recorded on the recording medium 16, the process proceeds to step S504. If the page is not normally recorded on the recording medium 16, the process proceeds to step S506, where the memory management means 23 notifies the file management means 21 that a failure has occurred in the recording medium 16 that is recording data, and the file Upon receiving the notification from the memory management unit 23, the management unit 21 stops data recording on the recording medium 16 where the failure has occurred (step S506).
[0069]
In addition, the memory management unit 23 clears the update flag part 42 of the corresponding entry in the page table 40 (step S504).
It is determined whether writing to the recording medium 16 has been completed for all of the indirect block entries assigned to the video / audio file (step S509). When the writing is completed, the memory management unit 23 notifies the file management unit 21 that the writing of the video / audio block to the recording medium is completed. If the writing has not been completed, the process proceeds to step S508.
[0070]
As described above, according to the third embodiment of the present invention, in the case of closing a video / audio file, the memory management unit 23 stores the video / audio block entry and the indirect block entry in the hierarchical file management information. Even when the video / audio file is closed, even when the video / audio file is closed, the video / audio data management information and By writing the indirect block information to the recording medium, the number of management data to be held in the memory can be reduced, so that the used capacity of the memory 22 can be reduced.
[0071]
【The invention's effect】
Recording device in the present invention Is In particular, the hierarchical file management information for managing the video / audio data every time the video / audio data is recorded on the recording medium is created and stored in the memory, and the updated hierarchy is stored in the memory. Record audio / video data by assigning page write priority levels according to the hierarchical level of the type file management information, and always recording the hierarchical file management information from the memory to the recording medium in the order of the assigned page write priority levels. Even if an abnormal termination of the recording device due to a power failure occurs at times, without recovering the file after recovery from the abnormal termination, the file management information recorded from the start of recording to immediately before the power failure is reproduced from the recording medium, The file management information lost from the memory due to power failure can be guaranteed by the recording medium.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a recording apparatus according to a first embodiment of the invention.
FIG. 2 is a diagram showing a file structure of a recording medium in the first embodiment of the invention,
FIG. 3 is a diagram showing the data arrangement of the file structure of the recording medium in the first embodiment of the invention;
FIG. 4 is a diagram showing a page frame on a memory according to the first embodiment of the present invention;
FIG. 5 is a diagram showing a configuration of a page table in the first embodiment of the present invention;
FIG. 6 is a flowchart showing a recording method according to the first embodiment of the invention.
FIG. 7 is a diagram showing a flowchart of a page-in operation in the first embodiment of the present invention;
FIG. 8 is a flowchart showing a page-out operation according to the first embodiment of the present invention;
FIG. 9 is a diagram showing a configuration of a virtual address in the first embodiment of the invention;
FIG. 10 is a diagram for explaining address translation in the first embodiment of the present invention;
FIG. 11 is a flowchart showing an update page recording processing operation in the first embodiment of the invention;
FIG. 12 is a diagram showing an example of an update page writing interval in the second embodiment of the present invention;
FIG. 13 is a diagram showing another file structure of the recording medium in the first embodiment of the invention,
FIG. 14 is a diagram showing a flowchart of a recording start process in the third embodiment of the invention;
FIG. 15 is a diagram showing a conventional file structure;
FIG. 16 is a diagram showing the structure of a conventional file system and file recovery method.
[Explanation of symbols]
10 Recording device
11 Video input means
12 Audio input means
13 Encoding means
14 Image memory
15 Image memory control means
16 Recording media
20 File Structure Management Department
21 File management means
22 memory
23 Memory management means
24 page control means
30 Encoding means
31 Video output means
32 Audio output means
40 page table
41 Page number part
42 Update flag part
43 Page write priority level
50 virtual addresses
101 Volume management file
102 Directory file
103 Indirect block file
104 Video / audio block file
200 page management area
1001 Root directory
1002 File allocation table
1003 cluster
1101 Process
1102 External recording device
1103 Update log
1104 Backup update log
1105 Hash table
1106 File management block
1107 files
1108 directory
1111 File management means
1112 File access means
1113 File repair means
1114 Hash table creation means

Claims (3)

A data management area in which video / audio data in which an input video signal or audio signal is encoded is recorded, and a page management area configured in a hierarchical manner with a plurality of files for managing the video / audio data recorded in the data area A recording medium having
The video / audio data is recorded in the data area of the recording medium, and each time the video / audio data is recorded in the data area of the recording medium , management information of a plurality of files for managing the video / audio data is updated and updated. File management means for storing the management information in a memory;
Assign a higher level from the lowest level of a page write priority levels in the order in accordance with the hierarchical level of the file of the management information store in the memory, the memory high order of the page write priority levels assigned And a memory management unit for recording the stored management information in a page management area of the recording medium. The frame rate of the video and audio data recorded on a recording medium acquired from said file management unit, wherein based on the frame rate obtained from the file management means, the management information stored in said memory said recording medium recording apparatus according to claim 1, further comprising a page control means for determining the write-free timing written in the page management area. When the recording of the video / audio data on the recording medium is completed and the video / audio file in which the video / audio data is recorded is closed, the memory management unit includes the video / audio data management information and the management information of the plurality of files. recording apparatus according to claim 1 or 2, wherein the writing the page containing the indirect block information to the recording medium.

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