JP2004192402A - Recording method and recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recording apparatus which is protected from file destruction and information loss in the occurrence of abnormal termination of information recording resulting from a power failure or the like in the middle of information recording to a recording medium and enables recording to be started in a short period of time after restoration from an abnormal state. <P>SOLUTION: Inputted audiovisual data is recorded in a recording medium 16, and hierarchical file management information for managing audiovisual data is generated and stored in a memory 22 at each time audiovisual data is recorded in the recording medium, and page write priority levels are assigned in accordance with hierarchical levels of hierarchical file management information stored and updated in the memory 22, and hierarchical file management information is recorded in the recording medium 16 in the order of the page write priority levels. Thus, file management information recorded by the date when abnormality occurs is reproduced from the recording medium after restoration from the abnormal state to compensate for file management information which has lost from the memory due to abnormality of power supply. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a recording apparatus and a recording method for expanding and reproducing an image recorded by compression, and more particularly to a recording apparatus and a recording method for preventing file destruction and information loss when a recording apparatus abnormally ends due to a power failure or the like. .
[0002]
[Prior art]
Conventionally, a surveillance system has installed a surveillance camera at a certain location, monitors the video while playing it back in real time on a monitor, stores the monitoring video in a recording and playback device, and plays back the recorded video as necessary I am trying to do it. In a recording / reproducing apparatus that simultaneously performs reproduction and search while recording, stores all management information created on a 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. Although it is desirable, in a recording / reproducing apparatus that performs image recording while holding all management information on a physical memory having only a limited address space, a magnetic disk or a disk that can be managed according to the mounted physical memory capacity is used. There is a problem that the recording capacity of the optical disc is limited. Therefore, by mounting a paging function, which is a method of virtual storage, on a recording / reproducing apparatus, management of a large-capacity recording medium using a small-capacity memory is realized.
[0003]
Incidentally, disk storage media such as a magnetic disk and a magneto-optical disk which can be randomly accessed have been used as storage media of the recording / reproducing apparatus. In the case of a conventional tape medium, 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 processing is not correct, from the start of recording There was a problem that all the monitoring images up to the power failure were lost.
Hereinafter, data recording on a disk recording medium configured for a computer will be described with reference to FIG. 15 (for example, see Non-Patent Document 1).
[0004]
[Non-patent document 1]
FileAllocationTable type file structure defined in JIS X0605 standard.
[0005]
FIG. 15 is a diagram showing a file structure defined by 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 the minimum unit for recording and reproduction on the 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 in the disk recording medium from the cluster number 0002, and the file allocation table 1002 indicates that Data1 has the cluster number 0002, cluster number 0003, And the cluster number 0004 in this order. Therefore, it indicates that the actual data of Data1 is stored in the areas of the cluster number 0002, the cluster number 0003, and the cluster number 0004 of the cluster 1003. Note that FFFF of the file allocation table 1002 is a cluster number indicating the last 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 in 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.
When writing data to the file allocation table 1002 and each area of the cluster 1003 during data recording, it is necessary to update the cluster connection information of the file allocation table 1002 every time the cluster 1003 is written. It is necessary to seek the write head, and the write speed becomes extremely slow.
[0008]
Therefore, the data of the file allocation table 1002 is written in the cluster 1003 while updating the information of the file allocation table 1002 in the memory, and the information of the file allocation table 1002 is reflected on the disk recording medium at the time of the data recording end processing or periodically. That method is adopted.
Conventionally, a file recovery method as shown in FIG. 16 has been known (for example, see Patent Document 1).
[0009]
[Patent Document 1]
JP-A-2000-40023 (page 5, 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 storage area for backup of the update log 1103, and a hash that stores a directory for restoration 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 in which the names of the files and information related thereto are collected. The file management unit 1111 includes a file access unit 1112 for accessing the file 1107 in accordance with the application program of the process 1101, a file restoration unit 1113 having a program that operates on the external storage device 1102 when the file 1107 is restored, and a hash function And a hash table creating unit 1114 that forms a table in accordance with
[0011]
When the use of the external storage device 1102 is started, 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 access to the file 1107, the hash table 1105 is searched first, and if the file is to be restored, the file is restored and then the file 1107 is accessed.
As described above, according to the conventional file system and file recovery method, the file recovery processing is performed based on the update log 1103 recorded in the external storage device 1102. No loss occurs.
[0012]
[Problems to be solved by the invention]
However, in the conventional recording on the disk recording medium, if a power failure occurs before the recording end process is performed, the file allocation table 1002 of the disk recording medium is not updated, and the By the time, the connection information in the file allocation table 1002 indicating the connection information of the cluster 1003 is lost even though the data has been recorded in the cluster 1003, which causes a problem of file destruction and data loss. Was.
[0013]
By periodically updating the file allocation table on 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 is necessary to restore the connection information of the cluster, there is a problem that the transition to the recording start state after recovery from the abnormal termination is delayed.
[0014]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-described conventional problem. When an abnormal termination of information recording occurs due to a power failure or the like while recording information on a disk recording medium, file destruction and loss of information are performed. The present invention provides a recording apparatus and a recording method capable of causing a transition to a recording start enabled state in a short time after recovery from an abnormal state without occurrence of an abnormal state.
[0015]
[Means for Solving the Problems]
In the recording method according to the present invention, the input video / audio data is recorded on a recording medium, and each time the video / audio data is recorded on the recording medium, hierarchical file management information for managing the video / audio data is created and stored in a memory. And assigning a page write 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 write priority levels. It has a configuration of having each step of recording 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 recording of audiovisual data, file management performed from the start of recording to immediately before the power failure without performing file restoration processing after the restoration of the abnormal state. The information can be reproduced from the recording medium, and the file management information lost from the memory due to the power failure can be guaranteed by the recording medium.
[0016]
The recording method according to the present invention has a configuration including 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, the hierarchical file management information can be efficiently recorded, and the number of data lost at the time of a power failure or the like can be minimized.
[0017]
In the recording method according to the present invention, the step of recording the hierarchical file management information on the recording medium includes, when recording of the hierarchical file management information on the recording medium is completed and the video / audio file is closed, It is configured to include a step of writing a page including video / audio data management information and indirect block information in the file management 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 the 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 is configured to create a recording medium for recording input video and audio data, and hierarchical file management information for managing the video and audio data each time the video and audio data is recorded on the recording medium, and store the file in the memory. File management means for storing, and assigning a page write priority level according to the hierarchical level of the hierarchical file management information stored and updated in the memory, wherein the hierarchical file is assigned in the order of the assigned page write priority level A memory management unit for recording 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 recording of audiovisual data, file management performed from the start of recording to immediately before the power failure without performing file restoration processing after the restoration of the abnormal state. The information can be reproduced from the recording medium, and the file management information lost from the memory due to the power failure can be guaranteed by the recording medium.
[0019]
The recording apparatus according to the present invention is configured such that the recording apparatus includes a page control unit that determines a writing 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, the hierarchical file management information can be efficiently recorded, and the number of data lost at the time of a power failure or the like can be minimized.
[0020]
In the recording device according to the present invention, the memory management means may include, when the recording of the hierarchical file management information on the recording medium is completed and the video / audio file is closed, the video / audio data management of the hierarchical file management information. A page including information and indirect block information is written on 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 the file management information to be held in the memory can be suppressed, the memory usage capacity can be reduced.
[0021]
A program according to the present invention is a computer that records input video and audio data on a recording medium, and creates hierarchical file management information for managing the video and audio data each time the video and audio data is recorded on a recording medium. And assigns a page write priority level according to the hierarchical level of the hierarchical file management information stored and updated in the memory, and assigns the hierarchical file management information in the order of the assigned page write priority levels. It has a configuration for realizing each function to be recorded 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 recording of audiovisual data, file management performed from the start of recording to immediately before the power failure without performing file restoration processing after the restoration of the abnormal state. The information can be reproduced from the recording medium, and the file management information lost from the memory due to the power failure can be guaranteed by the recording medium.
[0022]
The program according to the present invention is configured to make a computer realize a function of determining a writing 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, the hierarchical file management information can be efficiently recorded, and the number of data lost at the time of a power failure or the like can be minimized.
[0023]
The program according to the present invention, the function of recording the hierarchical file management information on the recording medium, the computer, when the recording of the hierarchical file management information on the recording medium is completed and the video and audio file is closed, It is configured to include a function of realizing a function of writing a page including video / audio data management information and indirect block information in the hierarchical file management 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 the 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 by using a recording medium, the recording method of the present invention can be realized by the computer at the transfer destination, and a recording apparatus can be realized. You can do it.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, 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 device 10 includes a video input unit 11 for converting an input video signal to digital, an audio input unit 12 for converting an input audio signal to digital, a video input unit 11 and an audio input unit 12. Encoding means 13 for encoding the digital data from the digital camera to generate video / audio data, an image memory 14 for temporarily storing a plurality of video / audio data, and an image memory 14 for storing the video / audio data generated by the encoding means 13 An image memory control unit 15 for controlling the transfer to or writing to the recording medium 16, a recording medium 16 for recording the video and audio data, and creating a hierarchical file structure each time the video and audio data is recorded on the recording medium. A file that stores the updated, created, or updated hierarchical file structure in a corresponding page in the memory 22. The address space is divided into page frames, 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 is divided into pages. And a memory management unit 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 pages stored in the memory 22. , A page control unit 24 for instructing the memory management unit 23 to write the updated page in the memory 22 to the recording medium 16, and the recording medium 16, the encoding unit 13, and the decoding unit 19 in cooperation with the file management unit 21. A file structure management unit 20 for controlling the video and audio data recorded on the recording medium 16; It comprises decoding means 30 for separating digital data of images and sounds, video output means 31 for converting digital data of video to video signals, and audio output means 32 for converting digital data of audio to audio signals. I have.
[0026]
The page control unit 24 requests the file management unit 21 to obtain the total frame rate of the video / audio file during the recording operation, and updates the updated page in the memory 22 based on the total frame rate obtained from the file management unit 21. Then, an interval or timing for instructing the writing of 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 onto the recording medium 16 may be designated at any time, for example, when updating a page. By setting the details, the file management information can be recorded at the time of restoration after a power failure. We can guarantee its existence.
The recording medium 16 is a recording device that can be accessed randomly, such as a hard disk (HDD), and includes one or a plurality of devices. The video and 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 the actual information) of the recording medium 16 of the recording apparatus according to the present embodiment will be described with reference to FIG.
2, the file structure of the recording medium 16 includes a volume management file 101, a directory file 102, a directory file 102, an indirect block file 103, and a video / audio block file 104.
[0028]
The volume management file 101 shown in FIG. 2 includes a free directory entry number, a free indirect block entry number, and a free video / audio block entry number, and the free directory entry number includes 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 empty entry of the directory file 102. In the empty indirect block entry number, the leading empty 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 leading empty 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. Indicates that the entry is empty. In the present embodiment, the directory entry 102, the indirect block file 103, and the video / audio block file 104 are used in order from the first entry. That is, at the time of data recording, the entry to be used is determined based on the empty directory entry number, the empty indirect block entry number, and the empty video / audio block entry number recorded in the volume management file 101.
[0029]
The directory file 102 is composed of a plurality of directory entries, and each directory entry is composed of a video / audio file name, a time stamp, a double indirect block pointer, and the number of video / audio data.
The double indirect block pointer records a double indirect block number, and the 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 the 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]
The number of video / audio data records the number of video / audio data recorded in the corresponding video / audio file. In the example of FIG. 2, 4 is recorded, indicating that four pieces of video and audio data are recorded in the video and audio file “AV1”. The indirect block file 103 includes a plurality of indirect block entries, and each indirect block entry includes a plurality of indirect pointers or direct pointers. In the indirect pointer, an indirect block entry number is recorded. In the indirect block, a direct pointer (management value) indicating the video and audio entry number in which the recording position and data size of the video and audio data recorded on the recording medium 16 are recorded. Direct access) is recorded. In the example shown in FIG. 2, three direct pointers are recorded in each indirect block.
[0031]
The entry number of the video / audio block file 104 that manages the recording position and data size of the video / audio data recorded on the recording medium 16 is recorded in the direct pointer. In the example shown in FIG. 2, 0 is recorded as 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. The first pointer is recorded as 1, 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. And the third pointer indicates that 2 is recorded, and the recording position and data size of the third video / audio data forming the video / audio file are recorded in the video / audio block entry 2, and the third pointer is indirectly recorded. As 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 FFFF of the second pointer and the third pointer of the indirect block entry 2 indicates that the video and audio data indicated by the video and audio block entry 4 is the last data of the video and audio file “AV1”.
[0032]
The video / audio block file 104 is composed of a plurality of video / audio block entries, and each video / audio block entry is composed of a recording position and a data size. In the example of FIG. 2, 0 and 10 are recorded in the recording position and the data size of the video / audio block entry 0, which indicates that the video / audio data is recorded at that position.
[0033]
Next, with reference to FIG. 3, the data arrangement of the file structure of the recording medium 16 of the recording apparatus according to the present embodiment will be described.
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 by virtual storage (paging). Note that an area on the recording medium 16 including 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 the video / audio data recorded in the data area 105 of the recording medium 16 is reproduced, the video / audio data is reproduced based on the double indirect block pointer recorded in the directory entry (for example, 0000). By acquiring three pieces of management data (double indirect block entry 0, indirect block entries 1, 2, and video / audio block entries 0 to 3), the recording position and size of the video / audio data to be reproduced are obtained. 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 consecutively arranged. However, they can be dispersedly arranged.
[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. Have been assigned. Also, the pages constituting the video / audio data file 104 are assigned page numbers 2000 to 2FFFF.
[0036]
FIG. 4 is a diagram showing a state in which the address space of the memory 22 is divided into page frames. The page frame indicates a unit corresponding to the page in the memory 22, and the size of the page and the page frame are always the same.
In FIG. 4, there are ten page frames on the memory 22, and the pages on the recording medium 16 are loaded into the page frames on the memory 22 as necessary at the time of data recording and reproduction.
[0037]
Next, a data structure of the page table 40 in the memory management unit 23 of the printing apparatus according to the present embodiment will be described with reference to FIG.
In the page table 40, one page entry is allocated for each page frame (FIG. 4) in the memory 22. In the example of FIG. 5, the page table 40 is configured by ten page entries (page entries 0 to 9), and information relating to 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 entries (0 to 9) include a page number section 41, an update flag section 42, and a page write priority level section 43.
The page number of the page loaded in the corresponding page frame on the memory 22 is recorded in the page number section 41. In the example of FIG. 5, 0 is recorded in the page number section 41 of the page entry 0, and the page 0 in the page management area 200 (FIG. 3) of the recording medium 16 is loaded into the page frame 0 in the memory 22. It indicates that. 7 is recorded in the page number section 41 of the page entry 1, indicating that the page 7 in the page management area 200 has been loaded into the page frame 1 in the memory 22. 8 is recorded in the page number section 41 of the page entry 2, indicating that the page 8 in the page management area 200 has been loaded into the page frame 2 in the memory 22. 2000 is recorded in the page number section 41 of the page entry 3, indicating that the page 2000 in the page management area 200 has been loaded into the page frame 3 in the memory 22. In the page number section 41 of the page entry 4, “1” is recorded, which indicates that the page 1 in the page management area 200 has been loaded into the page frame 4 in the memory 22. Note that FFFF in the page number section 41 indicates that there is no page in the corresponding page frame and the page frame is empty.
[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 section 42 is cleared as an initial state, when the page is updated, a mark is added, and the updated page is written to the recording medium 16. Is cleared when Marks (M) indicating data update are recorded in the update flag sections 42 of the page entries 0, 1, 2, and 3, and the pages 0, 7, and 8 and 2000 are updated.
[0040]
The page write priority level section 43 records page write priority levels 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 write priority level of the page entries 0 and 4, which means that pages 0 and 1 in the page management area 200 are pages belonging to the directory file 102. Is shown. 2 is recorded in the page write priority level 43 of the page entries 1 and 2, indicating that pages 7 and 8 in the page management area 200 are pages belonging to the indirect block file 103. As the page write priority level of the page entry 3, "3" is recorded, indicating that the page 2000 in the page management area 200 is a page belonging to the video / audio block file 104.
[0041]
Next, with reference to FIGS. 2 and 6 to 11, an operation of recording video and audio data input to the recording device according to 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 unit 11 and the audio input unit 12 convert the input information into digital data, encode the digital information by the encoding unit 13, and convert the video and audio data. Generate. The image memory control unit 15 stores the video and audio data generated by the encoding unit 13 in the image memory 14 and instructs the file management unit 21 to write the data on the recording medium 16. Upon receiving the write instruction from the image memory control unit 15, the file management unit 21 records the video and audio data on the recording medium 16 (step S101).
[0042]
The file management means 21 is a video / audio storage destination of information (recording position, data size) on video / audio data recorded on the recording medium 16 based on the free 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 unit 21 stores information (video / audio data) in the video / audio block entry 4 of the video / audio block file 104. (Recording position, data size).
[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), a free indirect block is acquired based on the free indirect block entry number of the volume management file 101. Then, the video / audio block entry number is recorded in the direct pointer of the empty 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 of the directory entry (0000 in FIG. 2) is updated. In the example of FIG. 2, the number of video and 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 video / audio block file 104 are used, the empty entry numbers of the volume management file 101 are updated (step S102).
[0044]
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, the file management means 21 instructs the memory management means 23 to convert the virtual address into a physical address. . Here, the virtual address indicates a recording position of the directory entry, the indirect block entry, and the video / audio block entry in the management information area 200. As shown in FIG. 9, the virtual address 50 includes a page number portion and an address within a page (step S103).
[0045]
When the memory management unit 23 is instructed to convert the virtual address to the physical address from the file management unit 21, the memory management unit 23 refers to the page number part 41 in the page table 40 (FIG. 5), and refers to the virtual address 50 (FIG. 9). A search is performed to determine whether or not a page number (page entry) that matches the page number in ()) exists (step S104). If there is no corresponding page, a page-in process (described later) is performed (step S105). If the corresponding page exists, the memory management unit 23 performs the 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 divided into a page number 0002 and an in-page address α. The memory management means 23 searches for a page entry of the page table 40 including the page number 0007, and when the corresponding page entry 1 is found, replaces the page number 0007 of the virtual address 50 with the page frame number 1 and generates a physical address. I do.
[0047]
Returning to step 107 in FIG. 6, the file management unit 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 unit 23. It notifies the memory management unit 23 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.
Upon receiving the page update notification from the file management unit 21, the memory management unit 23 puts a mark (M) on the update flag unit 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 to the memory 22 of the recording apparatus according to the first embodiment of the present invention will be described with reference to a flowchart of FIG.
When an instruction to read a page from the recording medium 16 is issued, the memory management unit 23 determines whether or not there is a free page frame in the memory 22 by checking whether the page number portion 41 of each page entry in the page table 40 has a free page. It is determined by checking whether or not the frame is FFFF (step S201). If there is no empty page frame, the process proceeds to the page-out process (step S202). If there is an empty page frame, an empty page frame to which the page is to be transferred is acquired (step S203).
[0049]
The memory management unit 23 reads the corresponding page from the recording medium 16 and stores the page in the acquired page frame. At this time, a group of pages including the corresponding page may be collectively pre-read. The pre-reading here means that a page to be referred to in the future is loaded on the memory 22 in advance (step S204).
The memory management unit 23 records the page number of the corresponding page in the page number section 41 of the corresponding page entry of the page table 40 (step S205), and based on the page number of the corresponding page, the file type to which the page belongs Is determined, 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, a page-out operation of information from the memory 22 to the recording medium 16 of the recording device according to the first embodiment of the present invention will be described with reference to a 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 section 42 of the corresponding entry of the page table 40 (Step S302). If the page is not updated, the process proceeds to step 306. If the page is an update page, the process proceeds to step S303, 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 the process has been completed normally (step S304). If the page has been normally recorded on the recording medium 16, the process proceeds to step S305. If 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 on which data is being recorded. Upon receiving the notification from the management unit 23, the data recording on the recording medium 16 in which the failure has occurred is stopped (step S308).
[0051]
The memory management unit 23 clears the update flag section 42 of the corresponding entry of the page table 40 (step S305), records FFFF in the page number section 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 write priority level section 43 of the corresponding entry in the page table 40 (Step S307).
[0052]
Next, an operation of writing an updated page in the recording apparatus according to the first embodiment of the present invention will be described with reference to a flowchart of FIG.
When the memory management unit 23 receives a write request for an updated page from the page control unit 24, the memory management unit 23 refers to the update flag unit 42 and the page write priority level 43 of each page entry of the page table 40, and saves it in the corresponding page frame. It is determined whether the written page is an updated page of page write priority level 3 (step S401).
[0053]
If the page is not an update page of page write priority level 3, the process proceeds to step S405. If the page is an update page of page write priority level 3, the process proceeds to step S402 to verify the corresponding page to a predetermined position on the recording medium 16. The recording is performed by the operation, and it is determined whether or not the recording of the page on the recording medium 16 is normally completed based on the response result by the verify recording operation (step S403). Therefore, if the page has been 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 unit 23 notifies the file management unit 21 that a failure has occurred in the recording medium 16 on which data is being recorded. Upon receiving the notification from the memory management unit 23, the management unit 21 stops recording data on the recording medium 16 in which the failure has occurred.
[0054]
In step S404, the update flag section 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 of 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, and the page stored in the corresponding page frame is written in the page by referring to the update flag section 42 and the page writing priority level 43 of each page entry of the page table 40. It is determined whether or not the page is a priority level 2 update page (step S406).
[0055]
If the page is not an update page of page write priority level 2, the process proceeds to step S407. If the page is an update page of page write priority level 2, the process proceeds to step 402, where the corresponding page is recorded in a predetermined position on the recording medium 16 by a verify operation, and the recording medium is recorded based on a response result of the verify recording operation. Then, it is determined whether or not the recording of the page to the P.16 has been completed normally (step S403). If the page has been normally recorded on the recording medium 16, the process proceeds to step S404. If the page has not been normally recorded on the recording medium 16, the memory management means 23 notifies the file management means 21 that a failure has occurred in the recording medium 16 on which data is being recorded. In response to the notification from the means 23, the data recording on the recording medium 16 in which the failure has occurred is stopped (step S411).
[0056]
In step S404, the update flag section 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 all the updated pages of 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. If the recording is completed, the process proceeds to step S408, and the page stored in the corresponding page frame is referred to as the page writing priority by referring to the update flag section 42 and the page writing priority level 43 of each page entry of the page table 40. It is determined whether the page is a level 1 update page (step S408).
[0057]
If the page is not an update page of page write priority level 1, the process proceeds to step S409. If the page is an update page of page write priority level 1, the process proceeds to step 402, where the corresponding page is recorded in a predetermined position on the recording medium 16 by a verify recording operation, and recording is performed based on a response result by the verify recording operation. It is determined whether the recording of the page on the medium 16 has been completed normally (step S403). If the page has been normally recorded on the recording medium 16, the process proceeds to step S404. If the page has not been 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 on which data is being recorded. In response to the notification from the means 23, the data recording on the recording medium 16 in which the failure has occurred is stopped (step S411).
[0058]
In step S404, the update flag section 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 all the updated pages of 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]
Thus, at the time of writing the update page, the update pages corresponding to the lowest level of the hierarchical file structure are sequentially recorded, and if a failure occurs in the recording medium 16 during the writing of the update page, the page writing process is immediately stopped. Thus, the file structure on the recording medium 16 can be prevented from being destroyed, and the recorded file can be reproduced without performing file restoration.
[0060]
Next, a file structure of the recording device according to the first embodiment of the present invention, which is different from that shown in FIG. 1, will be described in detail with reference to FIG.
FIG. 13 is a diagram showing a file structure when one piece of video / audio data is newly recorded for 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 and audio data of the directory entry 0, which indicates that five video and audio data are recorded in the video and 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. To indicate 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, if an abnormal end occurs before the update page writing process on the recording medium 16 is completed, the video newly stored on the recording medium 16 and stored in the memory 22 Although the entry information relating to the audio data (the second pointer of the indirect block entry 2 and the video / audio block entry 4) will be lost, since the hierarchical file structure shown in FIG. At the start of energization, the entry information recorded immediately before the previous 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 every time video / audio data is recorded on the recording medium 16, and the created or updated hierarchical file structure is created. And 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 stored in the memory 22. This is a recording device having a memory management unit 23 that controls access to a page, and assigns a page write priority level in advance to each layer of a hierarchical file structure, and records an updated page on the recording medium 16. By recording in order from the page having the highest page write priority level, even if an abnormal termination such as a power failure occurs during data recording, Since the file information has already been recorded on the recording medium 16 when the power supply is restarted, the file information that has been lost from the memory 22 due to the power supply failure can be restored from the start of recording to immediately before the power failure without performing the file information restoration process after the power failure. By being able to reproduce the data recorded until then, the file information lost from the memory 22 due to the power failure can be guaranteed, and the recording can be resumed quickly after the failure is eliminated.
[0063]
(Second embodiment)
Next, a recording apparatus according to a second embodiment of the present invention will be described in detail with reference to FIG. The present embodiment is different from the first embodiment in that the setting of the page writing interval for the recording device 16 is controlled by the page control unit 24.
That is, the page control unit 24 requests the file management unit 21 to acquire the total frame rate of the file management information during the recording operation from the recording device 16, and based on the total frame rate acquired from the file management unit 21. , An interval or timing for instructing writing of the updated page in the memory 22 to the recording medium 16 is determined.
FIG. 12 shows an example of an interval or timing for instructing the writing of the update page to the recording medium 16. In the period from 11:00 to 11:59, the recording operation is performed at a total of 30 frames / sec. 12:00 to 12:59 indicates that the recording operation is performed at a total of 60 frames / sec, and that 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 / sec, 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 reduced. At most, for example, 1200 frames can be guaranteed to minimize the number of lost data.
[0064]
(Third embodiment)
Next, a recording apparatus according to a third embodiment of the present invention will be described in detail with reference to FIG.
The recording device according to the present embodiment is different from the first embodiment in that when the video / audio file is closed (closed), the memory management unit 23 sets the video / audio The difference is that the page of the hierarchical file management information including the block entry and the indirect block entry is written to the recording medium 16.
[0065]
The operation of the printing 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 unit 21 requests the memory management unit 23 to write the video / audio block entry assigned to the video / audio file to the recording medium 16. Upon receiving the video / audio block entry write request from the file management unit 21, the memory management unit 23 acquires a page including the file management information from the pages held in the memory 21 (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 to the recording medium 16 is normal. It is determined whether the process has been completed (step S503). If the page has been normally recorded on the recording medium 16, the process proceeds to step S504. If the page has not been 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 on which data is being recorded. In response to the notification from the means 23, data recording on the failed recording medium 16 is stopped (step S506).
[0067]
In step S504, the memory management unit 23 clears the update flag section 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 video and audio blocks assigned to the video and audio file. As a result of the determination, 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, and proceeds to step S508. If the writing has not been completed, the process proceeds to step S501 (step S507).
[0068]
The file management unit 21 requests the memory management unit 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 recording of the page on the recording medium 16 is normal. It is determined whether the process has been completed (step S503). If the page has been normally recorded on the recording medium 16, the process proceeds to step S504. If the page has not been normally recorded on the recording medium 16, the process proceeds to step S506, in which the memory management unit 23 notifies the file management unit 21 that a failure has occurred in the recording medium 16 on which data is being recorded. Upon receiving the notification from the memory management unit 23, the management unit 21 stops recording data on the failed recording medium 16 (step S506).
[0069]
Further, the memory management unit 23 clears the update flag section 42 of the corresponding entry of 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 and audio files (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, when 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. By writing the corresponding page including the data to the recording medium 16, 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 By writing the indirect block information on 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】
The recording device and the recording method according to the present invention are configured as described above, and in particular, create hierarchical file management information for managing video / audio data every time video / audio data is recorded on a recording medium, and store it in a memory. A page write priority level is assigned according to the hierarchical level of the hierarchical file management information stored and updated in the memory, and the hierarchical file management information is always recorded from the memory to the recording medium in the order of the assigned page write priority levels. By doing so, even if an abnormal termination of the recording device due to a power failure or the like occurs during recording of audio / video data, file management performed from the start of recording to immediately before the power failure without performing file restoration processing after restoration of the abnormal termination The information can be reproduced from the recording medium, and the file management information lost from the memory due to the power failure can be assured by the recording medium. Kill.
[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 present invention;
FIG. 2 is a diagram showing a file structure of a recording medium according to the first embodiment of the present invention;
FIG. 3 is a diagram showing a data arrangement of a file structure of a recording medium according to the first embodiment of the present 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 according to the first embodiment of the present invention;
FIG. 6 is a diagram showing a flowchart of a recording method according to the first embodiment of the present invention;
FIG. 7 is a diagram showing a flowchart of a page-in operation according to the first embodiment of the present invention;
FIG. 8 is a diagram showing a flowchart of 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 according to the first embodiment of the present invention;
FIG. 10 is a diagram for explaining address conversion according to the first embodiment of the present invention;
FIG. 11 is a diagram showing a flowchart of an update page recording processing operation according to the first embodiment of the present invention;
FIG. 12 is a diagram showing an example of an update page writing interval according to the second embodiment of the present invention;
FIG. 13 is a diagram showing another file structure of the recording medium according to the first embodiment of the present invention;
FIG. 14 is a diagram showing a flowchart of a recording start process according to the third embodiment of the present invention;
FIG. 15 shows 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 section
42 Update flag section
43 Page write priority level section
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 recovery means
1114 Hash table creation means

Claims (10)

A step of recording the input video and audio data on a recording medium, and a step of creating hierarchical file management information for managing the video and audio data each time the video and audio data is recorded on the recording medium and storing the same in a memory; Assigning a page write 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 write priority levels. Recording on a medium. 2. The recording method according to claim 1, further comprising a step of determining a writing 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. . The step of recording the hierarchical file management information on the recording medium includes, when the recording of the hierarchical file management information on the recording medium is completed and the video / audio file is closed, 3. The recording method according to claim 1, further comprising a step of writing a page including audio data management information and indirect block information to the recording medium. A recording medium for recording the input video and audio data, and file management means for creating hierarchical file management information for managing the video and audio data each time the video and audio data is recorded on the recording medium and storing it in a memory, A page write priority level is assigned according to the hierarchical level of the hierarchical file management information stored and updated in the memory, and the hierarchical file management information is stored in the recording medium in the order of the assigned page write priority levels. A recording device comprising: a memory management unit for recording. 5. The apparatus according to claim 4, further comprising: a page control unit that determines a writing 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. Recording device. When the recording of the hierarchical file management information on the recording medium is completed and the video / audio file is closed, the memory management unit includes video / audio data management information and indirect block information of the hierarchical file management information. 6. The recording apparatus according to claim 4, wherein a page is written on the recording medium. A function of recording input video and audio data on a recording medium, and a function of creating hierarchical file management information for managing the video and audio data each time the video and audio data is recorded on a recording medium and storing the information in a memory. And a function of assigning a page write 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 the order of the assigned page write priority levels. A program for realizing a function of recording on the recording medium. 8. The computer according to claim 7, wherein a function of determining a write timing of said hierarchical file management information based on a total frame rate of said hierarchical file management information being recorded on said recording medium is realized. The program described. The function of recording the hierarchical file management information on the recording medium has a function of, when the recording of the hierarchical file management information on the recording medium is completed and the video / audio file is closed, 9. The program according to claim 7, further comprising a function of realizing a function of writing a page including video / audio data management information and indirect block information to the recording medium. A computer-readable recording medium on which the program according to claim 7 is recorded.

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