JP2006351089A - Method and device for recording and reproducing video image information - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce an unused area on a storage medium without damaging access performance to data in the case of recording the data of a long period. <P>SOLUTION: A method for recording and reproducing video image information encodes inputted image data, records the encoded image data in the storage medium (5) by each of prescribed data units (61, 62) and consecutively reproduces one or a plurality of pieces of the image data (61, 62) of the prescribed data units. The method prepares a data unit management information table (70) for storing encoded data of each of the prescribed data units (61, 62) consecutively in the data storage area (22) of the storage medium (5) and storing management information of the image data (61, 62) recorded by each of the prescribed data units (61, 62) in a management data area (21) on the storage medium (5). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a video information recording / reproducing method and apparatus, and more particularly to a video information recording / reproducing method applied to a monitoring application.

  In a conventional video information recording / reproducing apparatus, when recording a video, a method of encoding a video signal input from a camera or the like and recording it on a storage medium such as a video tape or a hard disk is generally used. For applications that require data, use intra-coding techniques such as JPEG (Joint Photographic Experts Group), which uses spatial redundancy in the frame to reduce the data size, and temporal redundancy between frames Accordingly, inter coding techniques such as MPEG (Moving Picture Expert Group) for reducing the data size are widely used.

  When intra coding technology is used, the data is independent for each frame, and on the storage medium, these encoded data are stored and managed in a fixed-length partition one or more. Has been.

  On the other hand, when inter coding is used, intra-coded key frames are coded first, followed by frames coded using inter-frame correlation in the time axis direction based on the key frames, and these are grouped together. As a result, a single unit that is significant as image information is formed. For example, in the case of MPEG-4, first, a header indicating data encoding conditions and the like, followed by I-VOP data, which is an intra-coded key frame, are sequentially correlated in time direction from I-VOP. Followed by the V-VOP encoded using. The range from a certain I-VOP to the V-VOP immediately before the next appearing I-VOP is referred to as a predetermined data unit here. On the storage medium, one or a plurality of predetermined data units are recorded and managed in fixed-length sections.

  By the way, when recording for a long time is required as seen in the example of monitoring application, it is important how efficiently the encoded data is recorded on the storage medium having a finite capacity. In the conventional technique, the maximum number of pieces of recording data stored in the data size of the fixed length section is stored. In such a management method, it is difficult to completely match the data size of the fixed-length partition with the data size of the predetermined data unit, so that an unused area occurs in the storage medium. Particularly in inter coding, since one predetermined unit data is generally a collection of a plurality of frame data, the unit data size is larger than that of one frame data of intra coding. The unused area in the case of being unable to fit in tends to be relatively large, and a large unused area is generated on the storage medium.

  As an improvement measure, the number of frames in a predetermined data unit is changed according to the amount of data after encoding, and encoding is performed so that a multiple of the predetermined data unit approaches the fixed-length partition data amount of the storage medium. There is one that reduces the unused area on the storage medium by controlling the processing (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2004-357086 (page 11, FIG. 2)

  However, according to the conventional technique, first, it is necessary to calculate the estimated code amount of the next input image and switch the encoding process, so that the processing is complicated by the calculation of the code amount estimation and the process switching. was there. Further, since the process is switched using the estimated code amount, the result of the actual encoding does not necessarily match the fixed-length partition data amount, and as a result, an unused area may occur. Further, when viewed from the viewpoint of efficiency at the time of encoding, even if the content of the recorded video is video content that can be efficiently recorded as an inter-encoded P-VOP without intra encoding, the fixed-length There has been a problem that the coding efficiency is lowered because the coding is forcibly switched to the intra coding due to the restriction on the data size of the section. Furthermore, in surveillance applications, etc., it is common to change the recording conditions using an external alarm or the movement of the surveillance image as a trigger, and it is widely used to view only the video associated with this alarm after recording. Therefore, when a trigger such as an alarm is input, it is desirable that the image at that time is intra-coded and can be accessed and played back from that time. Since the intra encoding timing is determined based on the fixed-length partition and the estimated cumulative data size, the alarm input time point is not necessarily intra-accessible at random access. There was a problem of poor accessibility, such as being unable to play back quickly.

  In addition, when the recordable area of the storage medium runs out, old recording data is deleted, and new data is recorded in the free space secured by that, but at this time also the same storage as above is performed. There has been a problem that the above-mentioned useless unused area occurs on the medium.

  The present invention has been made to solve the above-described problems, and in the video information recording / reproducing method, data recording is performed on a storage medium having a finite capacity without impairing random access performance to desired data. It is an object of the present invention to obtain a video information recording / reproducing apparatus that realizes long-time recording by reducing unused areas and reducing unused areas of a storage medium even when continuous recording is repeated.

  The present invention encodes input image data, records the encoded image data on a storage medium for each predetermined data unit, and continuously reproduces one or more of the image data in the predetermined data unit. In the video information recording / reproducing method, the encoded data for each predetermined data unit is continuously stored in a data storage area of a storage medium, and management data provided in an area different from the data storage area on the storage medium A video information recording / reproducing method is provided, wherein a data unit management information table for storing management information of image data recorded for each predetermined data unit is created in an area.

  As described above, according to the present invention, the encoded video data is continuously recorded on the storage medium in a predetermined data unit, and therefore it is generated due to the difference between the fixed length partition size on the storage medium and the encoded data size. It is possible to reduce the unused area of the storage medium and realize long-time recording. At this time, it is not necessary to control the encoding unit so that the recording data itself is equal to or smaller than a certain size as in the prior art, so that the processing load on the encoding unit can be reduced. In addition, a data unit management information table for accessing desired data is provided to manage the data. Since the head of the data indicated by the address is intra-coded data, the random accessibility to the data is impaired. There is nothing.

  Furthermore, even during continuous recording in which new data is recorded while deleting old data, the recording area and deletion area are managed by the data unit management information table provided on the storage medium, so the processing load is low. Thus, it is possible to reduce the unused area of the storage medium and continue the continuous recording.

Embodiment 1 FIG.
FIG. 1 is a diagram for explaining a video information recording / reproducing apparatus according to Embodiment 1 for carrying out the present invention, and more specifically, a block diagram for realizing the apparatus.

  A video information recording / reproducing apparatus 1 shown in FIG. 1 includes an image input unit 2, an image encoding unit 3, a data recording unit 4, a data storage unit 5 including a storage medium 5a, a management data generation unit 6, and the like. , A management data rewriting unit 7, a management data reading unit 8, a data reading unit 9, an image decoding unit 10, an image output unit 11, and a processing control unit 12.

  In FIG. 1, command input means directly connected to the video information recording / reproducing apparatus 1 for the user to specify recording start and stop, status display means for displaying the status of the device, image encoding and Parts that do not directly affect the effects of the present invention, such as data temporary storage means for temporarily storing data in the decoding process, and a display device for displaying the output image are omitted.

  In the video information recording / reproducing apparatus 1 of the first embodiment, a video input from a camera or the like connected to the image input unit 2 is controlled by the processing control unit 12 to a predetermined image quality and recording interval, and the image encoding unit 3, and the encoded data (image data) is recorded by the data recording unit 4 in the data storage unit 5 including the data storage medium 5 a for each predetermined data unit. In this data recording, management information of the recording data is generated by the management data generating unit 6 and recorded in the data storage unit 5.

  In the video information recording / reproducing apparatus 1, when reproducing the image data recorded in the storage unit 5, the management data read unit 8 reads out the management data recorded in the storage unit 5 and records desired image data. The data read unit 9 reads the desired data (image data) from the data storage unit 5 based on the information (address), and the image decoding unit 10 decodes the image data. Then, an image is output from the image output unit 11.

  Here, the data recording in the first embodiment will be described with reference to FIG. FIG. 2 is a diagram showing the data storage unit 5 and the storage area on the storage medium 5a of the data storage unit 5, 20 is the entire recording area of the data storage unit 5, and 21 is for storing management data A management data area 22 is an image data area for recording image data. As described above, in the video information recording apparatus 1 of the first embodiment, the recording area 20 of the data storage unit 5 is divided into the image data storage area 22 and the management data storage area 21 to record data.

  In the conventional data recording method, as described above, image data is recorded by a method of storing the maximum frame data that can be stored in each fixed-length partition. An unused area of data occurred due to a mismatch with the predetermined data unit size.

  In the above-mentioned Patent Document 1 for the purpose of reducing the unused area, the size of the predetermined data unit is changed by changing the number of frames in the predetermined unit data according to the estimated code amount by switching the process at the time of encoding. Is intended to reduce the unused area by controlling the size to approach the fixed-length partition size, but at this time, not only does the load on the control of the data size occur, but the figure in document 1 also shows In addition, unused areas still occur.

In the first embodiment, the data for each predetermined data unit is continuously stored in the data recording area without being divided by the fixed length section.
FIG. 3 shows an example of data storage in the data storage area of the first embodiment. In FIG. 3, 22 is an image data area on the storage medium, 41 to 55 are each one frame, 41 to 45 are one predetermined data unit 61, and 51 to 55 are the next predetermined data unit 62. It is. As described above, the data of each predetermined data unit is continuously recorded in time series without being divided into fixed length sections in the data area, and an unused area is not generated.

  When this image data is recorded, the management data generator 6 generates image management data to be recorded in the management data area 21. A specific example of this management data is shown in FIG. In FIG. 4, 70 is a data unit management information table, 71 is a data presence / absence flag that is the first item of management information, 72 is the recording date of image data that is the second item of management information, and 73 is the first item of management information. The recording time of image data that is three items, and 74 is the start address of the image data on the storage medium that is the fourth item of management information. This management data comprises one item of data consisting of four items: a data presence / absence flag 71, a recording date 72, a recording time 73, and a head address 74, and one piece of management data is created for each predetermined data unit. The image data is stored in the management data area on the storage medium in the order in which the image data is recorded.

In this data unit management information table 70, “one or more predetermined data units recorded one or more consecutively, and the total data size sum_data is a specified data size (specified maximum total data size) SIZE_GROUP_MAX If the following predetermined data unit is added and the total data size sum_data exceeds the specified data size (SIZE_GROUP_MAX) is treated as one group, the predetermined data unit in this group is stored in the data unit management information table 70. After the management information associated with each of the groups, empty management information that is not associated with the predetermined data unit is generated until the count of management information for one group reaches the specified number COUNT_NUM_MAX.
This will be described with reference to FIG. FIG. 5 is a flowchart for explaining the first management information creation process.

  First, in step 80, the total data size sum_data of a predetermined data unit is reset to “0”, and the management data number count is reset to “1”. (Specifically, “0” is written in the register holding the total data size size_data, and “1” is written in a register or counter (not shown) that stores or counts the number of management data counts. .)

  Next, in step 81, an encoding process for a predetermined data unit is performed. Next, in step 82, the encoded data is written to the storage medium. Next, in step 83, the encoded data size of the predetermined data unit is stored. size_unit is acquired (data size size_unit of a predetermined data unit is written to register size_unit), and in step 84, the acquired size size_unit of the predetermined data unit is added to the total data size sum_data, and the addition result is a new total data size. Let sum_data.

  In step 85, it is determined whether the total data size sum_data is larger than the prescribed data size SIZE_GROUP_MAX. If the total data size sum_data is not larger (NO in step 85), the predetermined data unit belongs to the current group. In step 86, one piece of management data is created for this predetermined data unit.

Thereafter, in step 87, 1 is added to the count of management information, and then the process returns to step 81 to repeat the processes in and after step 81.
On the other hand, when it is determined in step 85 that the total data size sum_data is larger than the specified data size SIZE_GROUP_MAX (YES in step 85), the process proceeds to step 88.

  In step 88, a group is formed by assuming that up to the predetermined data unit of the previous time point belongs to one group (that is, excluding the last encoded predetermined data unit from the group), In step 89, it is determined whether or not the count of management information created so far matches the specified number COUNT_NUM_MAX.

  If they do not match in step 89 (NO in step 89), empty management data that is not associated with a predetermined data unit is created in step 90, and "1" is added to the management information count in step 91 ( The count value count of the counter is increased by “1”), and the process returns to step 89.

By such processing, the empty management information until the number of management information created in step 89 (the sum of the number of management information associated with the predetermined data unit and the number of empty management information) reaches the specified number COUNT_NUM_MAX. Is created.
When the total count of management information count reaches the specified number COUNT_NUM_MAX (YES in step 89), in step 92, management data associated with the latest predetermined data unit from which the data size has been acquired is created.

Thereafter, in step 93, the management data count count is set to 1, and in step 94, the total data size sum_data is made equal to the data size size_unit of the latest predetermined data unit (the register size_data storing the total data size size_data is the latest). The value of the data size size_data of the predetermined data unit is set and initialized).
Next, the process returns to step 81, and the same processing as described above is repeated for the next group.

  Of the processes shown in FIG. 5, step 81 is executed by the image encoding unit 3, steps 86, 90, and 92 are executed by the management data generating unit 6, and other processes are executed by the process control unit 12. The Therefore, a register, a counter, and the like that store variables and constants (size_data, size_unit, count, SIZE_GROUP_MAX), and the like are provided in the processing control unit 12.

  An example of management data created by such processing is shown in FIG. FIG. 6 is an example of management data created by the processing of FIG. 5, and shows an example in which the prescribed number COUNT_NUM_MAX of the number of management data items for each group is 32.

  In FIG. 6, 22 is an image data area on the storage medium, 70 is a data unit management information table recorded in the management data area on the storage medium, and 100 to 107 are predetermined data recorded in the image data area 22. One unit (first group) G1 is composed of predetermined data units 100 to 104, and another group (second group) G2 is composed of predetermined data units 105 to 107. . Reference numerals 110 to 143 denote management data recorded in the data unit management information table 70. The management data 110 to 114 are associated with the predetermined data units 100 to 104 of the first group G1, and the management data 130 to 132 are associated with the predetermined data units 105 to 107 of the second group G2. It is.

Management data 120 to 122 and 141 to 143 are empty management data.
The sum of the number of management data 110 to 114 (5) and the number of management data 120 to 122 (27) is 32, the number of management data 130 to 132 (3) and the number of management data 141 to 143 (29) Is 32.

  As described above, in the illustrated example, the predetermined data units 100 to 104 are treated as constituting one group (first group) G1, and the management data associated with the predetermined data unit for this group G1. Empty management data is added so that the total number of cases 110 to 114 and empty management data 120 to 122 is the prescribed number 32.

  Similarly, the predetermined data units 105 to 107 are treated as constituting the next group (second group) G2, and management data 130 to 132 associated with the predetermined data unit for this group G2 and empty management Empty management data is added so that the total number of data 141 to 143 is the prescribed number 32.

  Next, a process in the case where continuous recording is performed on a storage medium using the management data configured as described above will be described. In monitoring applications, continuous recording is generally performed such as recording data for a long period of time such as days or months. In this case, data is recorded in order from the oldest data recorded in the past. Delete and record new data in the newly reserved free space. Also in this case, it is important not to create an unused area on the storage medium without impairing the accessibility to the data.

  In the first embodiment, a method of performing a continuous recording process using the data unit management information table 70 configured by the process described with reference to FIG. 4 will be described with reference to FIG. FIG. 7 is a flowchart for explaining a method of recording new data while deleting old data on the storage medium when there is no free space for new recording on the storage medium. In the present embodiment, the recorded data is deleted in units of groups described above.

  First, in step 150, the total size (deleted region size) sum_delete of the deleted region is set to 0. Next, in step 151, the value (group number) target_group specifying the group to be deleted is set to the oldest. In step 152, a flag flg_first for determining whether or not the group is the first group to be deleted is set to “1”.

  Subsequently, in step 153, the data size size_target occupied by this group is calculated from the management data corresponding to the first group using the data unit management information table 70 (data size is calculated and stored in the register size_target). To do). This data size is calculated based on the address value. That is, the start address 74 of the first data unit of one group and the start address of the first data unit of the next group are read, and the difference between them (the value obtained by subtracting the former from the latter) is set as the data size size_target. However, for the last data in the address, the end of the data is known by a separately managed pointer.

  Thereafter, in step 154, the data of the group designated by the group number target_group is deleted.

  Next, in step 155, the data size size_target calculated in step 153 is added to the total value (total data size) sum_delete of the deleted area sizes, and the addition result is set as a new total data size size_delete. The total data size size_delete indicates how much data has been deleted so far.

  In step 156, the target group number is incremented by one (ie, “1” is added to the group number (initially “1” representing the oldest group), and then the old group is designated. To the number you want).

  Next, in step 157, it is determined by referring to the flag flg_first whether the group deletion process executed in step 154 is performed for the first time. In step 158, the flag flg_first is set to “0”, the process returns to step 153, and steps 153 to 156 are performed once again.

  As described above, when Steps 153 to 156 are executed for the second time, if the determination in Step 157 is performed, the result is NO (the flag flg_first is not 1).

  In step 159, therefore, it is determined whether the total size (total data size) sum_delte of the deleted data is larger than the specified data size SIZE_GROUP_MAX at the time of recording.

  If the accumulated value sum_delete is less than or equal to the specified data size SIZE_GROUP_MAX (NO in step S159), the process returns to step 153, and the same process as above is repeated after step 153.

  In step 159, if the total data size (cumulative value) sum_delete is larger than the specified data size SIZE_GROUP_MAX (YES in step 159), the data deletion operation for securing the free space is temporarily suspended here, and the processing up to this point In step 160, new group data and management information are written into the reserved free space.

  In step 160, processing similar to that in steps 80 to 94 in FIG. 5 is performed. The total data size_data at the end of the process is temporarily stored as the total data size sum_group (stored in the register size_group).

In step 161, the total data size sum_group of the group recorded in step 160 is stored in the register sum_group, and in step 162, the newly recorded group data from the accumulated value (total data size) sum_delte of the deleted data size is stored. The size sum_group is subtracted, and the subtraction result is set as a new “cumulative value of deleted data size (total data size)” sum_delete (that is, the subtraction result is written in the register sum_delete). This cumulative value represents how much of the previously reserved free space remains.
Thereafter, the series of processes is repeated from the process 153 in the same manner.

  In the processing of FIG. 7, step 153 is executed by the management data reading unit 8 and the processing control unit 12, and step 154 is the data recording unit 4 (when data is actually erased) or the management data generation unit 6 (management data is stored). Other processing is executed by the processing control unit 12. Therefore, a register for storing variables, constants (flg_first, size_target, target_group, size_delete, size_data) and the like is provided in the processing control unit 12.

  By the way, in the present embodiment, since the data size of each predetermined data unit is not processed so as to have a fixed length, the number of predetermined data units in the group to be newly recorded is the predetermined number of the group previously deleted. A case different from the number of data units is conceivable, but as described above, in the data unit management information table, an empty management data area is added to each group, and the total number of management data is the specified number (FIG. 6). In the example shown in (3), since the number of data in the newly written group is larger than the number of data in the deleted group, the management of the predetermined data unit is possible without any problem as long as it does not exceed the specified number. Information can be created, and there is no inconsistency in management information for past data already recorded.

  When data is deleted during these series of processing, the data presence flag 71 in the data unit management information table 70 is rewritten from “1” to “0” by the management data rewriting unit 7 and data exists. When data is recorded, it is clearly indicated that data exists by rewriting the data presence / absence flag from “0” to “1”. This makes it possible to instantly know which data has been deleted in the management data search.

  With the configuration as described above, when image data is recorded on the storage medium 5a, the image data can be continuously recorded for each predetermined data unit without being divided into fixed length sections. Reduction of the above unused area can be realized. Further, even in continuous recording in which new data is recorded while deleting old data, the unused area can be reduced by the data management method using the data unit management information table 70. At this time, high-level data amount control in encoding as in the conventional example is not necessary, and can be realized with a simple configuration.

  Further, in this configuration, when the recorded data is reproduced, even if the data is not divided into fixed sections, the second item (72) and the third item (73) of the data unit management information table 70 are desired. The recording area of the desired data can be searched from the address described in the fourth item (74), and the head of the data indicated by this address is always intra-coded I Since it is a -VOP, reproduction from that part is possible, and there is an effect of realizing good access to desired data.

  In the data unit management information table 70, the prescribed number (COUNT_NUM_MAX) of the number of data to be allocated to one group may be allocated more than the maximum number that can be considered according to the encoding condition at the time of actual image data recording. There is no limitation to “32” as in the above example.

  In addition, the specified data size (SIZE_GROUP_MAX) for handling a group of one or more predetermined data units as a group also depends on the cache size and hardware configuration for realizing the device, and the size of encoded data to be recorded. It may be set accordingly, and is not limited to the numerical values in the above example.

  Further, when data is continuously recorded, the management data associated with the latest data is located in the middle of the data unit management table 70 instead of at the end. It can be known from the presence / absence flag 71. However, instead of doing this, a unique value indicating that the predetermined data unit is the last data, for example, 256 may be assigned to the data presence / absence flag 71 of the data unit management table 70, or The terminal pointer may be managed by another means such as a non-volatile memory provided on the apparatus.

  Further, the data stored in the data unit management information table 70 shown in the first embodiment is not limited to the above-described example. For example, date and time information is directly related to the date and time. It is not necessary to be a value, and it is sufficient that the date and time is uniquely determined by using arithmetic operations, for example, a method in which the date and time are simultaneously indicated by serial continuous values may be used. In addition to the items in the data unit management information table 70 shown in the example, attribute data such as a camera number and a sensor state may be included.

  Furthermore, when deleting data, it is not always necessary to delete the actual data area. It is clearly indicated that the data has been deleted only in the data unit management information table, and that the corresponding data area can be written. Just doing it doesn't matter.

Embodiment 2. FIG.
In the first embodiment, the data unit management information table shown in FIG. 4 is used, but in addition to that, the group management information table shown in FIG. 8 may be used.

  The group management information table 170 shown in FIG. 8 includes a data status flag 171 that is the first item of management information, a group total data size 172 that is the second item of management information, and a third item of management information. The group head address 173 is continuously recorded in the order of the recording date and time of the image data of each group. In the group management information table 170, one piece of management data of the first item to the third item is created for one group composed of the aforementioned predetermined data unit. In this group management information table 170, the data status flag 171 indicates that data of the group is recorded. If data is recorded, a value of 0x01 is set, for example, and the data is erased. In this case, a value of 0x00 is set.

  When recording data, the video information recording apparatus according to the second embodiment creates management data for each predetermined data unit in the data unit management information table 70 as in the first embodiment. A range in which the total data size value of one or more consecutive predetermined data units is less than or equal to the specified data size (SIZE_GROUP_MAX) is treated as one group. One piece of management data having the size and the top data address of the group is created, and this data is continuously recorded to form the group management information table 170.

  The group management information table 170 created in the second embodiment will be described with reference to FIG. In FIG. 9, 180 is the first management data of the group management information table 170, 181 is the second management data, and the other items with the same reference numerals as those in FIGS. It is equivalent to. In FIG. 9, the management data 110 to 122 in the data unit management information table 70 is handled as one group. In the group management information table 170, one record is assigned to the group corresponding to the management data 110 to 122. Management data 180 is generated. Similarly, the management data 130 to 143 in the data unit management information table 70 corresponds to one group, and one piece of management data 181 is generated for this group.

  When image data is recorded while creating such a data unit management information table 70 and a group management information table 170 in the management data area 21, if recording continues for a long time and the free space of the storage medium runs out, By deleting the oldest data, a free area for new data recording is secured, and continuous recording is continued. At this time, the data is processed by the above-described processing (first embodiment) for each group. However, by using this group management information table 170, continuous recording of data is performed without generating an unused area on the storage medium 5a. At this time, since the video information recording / reproducing apparatus can easily obtain from the group management information table 170 the number of groups that need to be deleted in order to secure a free space. Has the effect of reducing the processing load of the recording and reproducing apparatus, it is possible to realize an effect that even an unused area reduction in performance is low image information recording and reproducing apparatus.

  Note that the contents of the group management information table 170 are not limited to the illustrated example, and may include information other than the items shown in the above example for the purpose of another effect.

Embodiment 3 FIG.
10 and 11 are diagrams for explaining a video information recording / reproducing apparatus according to Embodiment 3 for carrying out the present invention. More specifically, FIG. 10 is a block diagram for realizing the apparatus. FIG. 11 is an explanatory diagram of a recording area on the storage medium 5a.

The video information recording / reproducing apparatus shown in FIG. 10 is generally the same as that shown in FIG. 1, and the same members as those in FIG. The apparatus shown in FIG. 10 is different in that a management data comparison unit 13 is added.
In FIG. 11, 190 is a first data unit management information table, 191 is a first group management information table, 192 is a second data unit management information table, 193 is a second group management information table, and 194 is A checksum table for the data unit management information table 195 is a checksum table for the group management information table.

  As shown in FIG. 11, in the video information recording / reproducing apparatus of the present embodiment, data unit management information tables (190, 192) are provided at two locations, and two group management information tables (191, 193) are provided. The data unit management information tables 190 and 192 have the same contents, and the group management information tables 191 and 193 also have the same contents. Further, a checksum table 194 for evaluating the validity of data is provided for the data unit management information tables 190 and 192, and a similar checksum table 195 is provided for the group management information tables 191 and 193. Is provided.

  In the video information recording / reproducing apparatus of the third embodiment, at the time of data recording, the data unit management information table (190, 192) is created in the two locations of the storage medium 5a by the management data generating unit 6. At this time, the data amount of the described contents is totaled for each fixed number of data units in the data unit management information table (190, 192), and a value representing the amount is added to the checksum table 194 for the data unit management information table. (Create a table or record in a table). Similarly, at the time of data recording, the management data generation unit 6 creates group management information tables (191, 193) with the same contents at two locations on the storage medium 5a. At this time, the group management information table (191) , 192), the total amount of data is calculated for each group and a checksum table 195 for the group management information table is created (recorded in the table).

In the operation of the video information recording / reproducing apparatus of the present embodiment, first, the management data comparison unit 13 compares the data in the two data unit management information tables 190 and 192 with each other and there is no difference between the data. Uses one of the data unit management information tables 190 or 192, for example, the first management information table 190 to search and manage data. If there is a difference between the two, the data amount of the portion where there is a difference is compared with the value recorded in the checksum table 194 in the management data comparison unit 13, and if either of them matches, the data matches The data unit management information table (one of 190 and 192) is switched to be used for data retrieval.
Similarly for the group management information tables (191, 193), the management data comparison unit 13 compares the data of the two management information tables 191 and 193 with each other. Data search and management are performed using a group management information table (one of 191 and 193), for example, the first group management information table 191. If there is a difference between the two, the data amount of the portion where there is a difference is compared with the value recorded in the checksum table 195 in the management data comparison unit 13, and if either matches, the match is found. The group management information table (one of 191 and 193) is switched to use it for data retrieval.

  The comparison processing of the data in the management information table may be performed based on a preset task schedule. For example, a method performed at a predetermined time every day or a certain amount of time after the apparatus starts operation. The method may be performed every time.

  With this configuration, in the video information recording / reproducing apparatus of the present embodiment that does not cause an unused area on the storage medium, a part of the data unit management information table and the group management information table is damaged for some reason. In this case, both the data unit management information table and the group management information table are provided, and the checksum table is provided, so that the management information table (data unit management information with no data corruption) is obtained. Table and group management information table) can be selected, and recording and reproduction can be continued.

  In this embodiment, two management information tables having the same contents are provided for both the data unit management information table and the group management information table, and each checksum table is provided. The position on the storage medium where the management information is recorded is not limited to the above example. For example, two management information tables (a data unit management information table and a group management information table) are successively (adjacent to each other). It may be recorded in a suitable area).

Embodiment 4 FIG.
FIG. 12 is a diagram for explaining a video information recording / reproducing apparatus according to Embodiment 4 of the present invention, and more specifically, a block diagram showing a configuration of the apparatus. In FIG. 12, reference numeral 14 denotes a management data storage unit, and components having the same reference numerals as those in FIG. 1 are the same or equivalent.

  In the video information recording / reproducing apparatus of the present embodiment, the image data is recorded in the data storage unit 5, and the data unit management information table 70 and the group management information table 170 are different from the data storage unit 5 that stores the image data. The storage medium 14a for storing the management data, which is recorded in the management data storage unit 14 having the medium 14a, is composed of, for example, a volatile memory. In general, since the image data size is enormous for long-time recording of image data, a storage medium with a low capacity unit price such as an HDD is used. However, the management data has a data size much larger than that of image data. Since the information is small, the information can be recorded in a semiconductor memory or the like.

  With this configuration, when the storage medium for recording the management information table is configured by a semiconductor memory in the video information recording / reproducing apparatus of the present embodiment in which an unused area is not generated on the storage medium. Since the access speed is generally higher than that of a storage medium such as an HDD, the time required to search for desired data when accessing the management information table (70, 170) and image data can be reduced. Realize performance. Also, compared to accessing both management data and image data on one medium, the number of accesses per medium can be reduced, and as a result, the number of accesses to the HDD, which is a consumable component, can be reduced. Can be reduced, and there is an effect of extending the life of the product.

  In the fourth embodiment, an example in which both the data unit management information table and the group management information table are recorded on a storage medium different from the storage medium for storing image data has been described. Alternatively, only the data unit management information table or only the group management information table may be recorded on a storage medium different from the storage medium that stores the image data, depending on the capacity of the management data storage unit 14 that can be used.

  When the data size of the management information table (70, 170) is relatively small relative to the size of the storage medium 14 for the management data amount area, the data unit management information table and the group management information table are stored. Each of the tables need not be limited to one, and a plurality of tables may be provided as described in the third embodiment. In this case, as described in the third embodiment, the management data comparison unit 13 is provided to perform the data comparison process of the management information table.

  Although the embodiments have been described above, in any of the embodiments, the video recording / playback apparatus may be configured with dedicated hardware, or realized by software processing means on a general-purpose personal computer. Also good.

1 is a block diagram for explaining a video information recording / reproducing apparatus according to Embodiment 1. FIG. FIG. 2 is a data storage area diagram for explaining the video information recording / reproducing apparatus of the first embodiment. FIG. 2 is a data storage structure diagram for explaining the video information recording / reproducing apparatus of the first embodiment. FIG. 3 is a management data configuration diagram for explaining the video information recording / reproducing apparatus of the first embodiment. 4 is a flowchart for explaining a data management method in the video information recording / reproducing apparatus of the first embodiment. FIG. 3 is a management data configuration diagram for explaining the video information recording / reproducing apparatus of the first embodiment. 4 is a flowchart for explaining a continuous recording operation in the video information recording / reproducing apparatus of the first embodiment. 6 is a management data configuration diagram for explaining a video information recording / reproducing apparatus according to Embodiment 2. FIG. 6 is a management data configuration diagram for explaining a video information recording / reproducing apparatus according to Embodiment 2. FIG. FIG. 10 is a block diagram for explaining a video information recording / reproducing apparatus in a third embodiment. FIG. 11 is a configuration diagram of a storage medium area for explaining a video information recording / reproducing apparatus of a third embodiment. FIG. 10 is a block diagram for explaining a video information recording / reproducing apparatus in a fourth embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Image | video information recording / reproducing apparatus, 2 Image input part, 3 Image encoding part, 4 Data recording part, 5 Data storage part, 6 Management data generation part, 7 Management data rewriting part, 8 Management data reading part, 9 Data reading Section, 10 image encoding section, 11 image output processing section, 12 control processing section, 13 management data comparison section, 14 management data storage section, 20 total data area, 21 management data area, 22 image data area, 30 fixed length section Area, 41 VOP1, 42 VOP2, 43 VOP3, 44 VOP4, 45 VOP5, 51 VOP6, 52 VOP7, 53 VOP8, 54 VOP9, 55 VOP10, 61 Predetermined data unit 1, 62 Predetermined data unit 2, 70 Data unit management information table 71 Data presence flag 72, recording date, 73 recording time, 74 start address, 100-107 predetermined data unit, 110-143 management data, 170 group management information table, 171 data status flag, 172 group total data size, 173 start address, 180-181 management data, 190 first data unit management table, 191 first group management table, 192 second data unit management table, 193 third group management table, 194-195 checksum table.

Claims (12)

Video information recording / reproduction that encodes input image data, records the encoded image data in a storage medium for each predetermined data unit, and continuously reproduces one or more of the image data in the predetermined data unit In the method
The encoded data for each predetermined data unit is continuously stored in a data storage area of a storage medium,
Creating a data unit management information table for storing management information of image data recorded for each of the predetermined data units in a management data area provided in an area different from the data storage area on the storage medium; Video information recording and playback method. In the data unit management information table,
One piece of management information of fixed length is created for each predetermined data unit. One piece of management information includes date and time information on which data of a predetermined data unit is recorded and head address information of the recorded data. The video information recording / reproducing method according to claim 1, wherein the management information is continuously configured in order of recording date and time. One or more predetermined data units continuously recorded in the data storage area,
If the total data size is less than or equal to the specified data size and the next predetermined data unit is added, the total data size exceeds the specified data size as one group,
In the data unit management information table, following the management information associated with each predetermined data unit in this group,
3. The video information recording / reproducing method according to claim 2, wherein empty management information that is not associated with each predetermined data unit is generated until the number of management information items for one group reaches a specified number. On the data storage area, when there is no more free space for recording data due to data recording, in the process of recording new data while securing old space by deleting old data,
When deleting the group that is composed of one or more predetermined data units and is recorded in a range where the total data size is less than or equal to the specified data size, the recorded data in order from the oldest recording date It is deleted in units of groups, and at the time of writing new data, at least two groups are always deleted, and a plurality of groups whose deleted data area size exceeds the specified data size are deleted. In addition, when recording new data, one group is recorded in a range where the total data size of the data to be recorded is equal to or less than the specified data size, and deletion and recording of these data groups are necessary. The video information recording according to claim 1, wherein a part of the data unit management information table is reconstructed at this time. Raw way.   A range in which the total data size of one or more predetermined data units continuously recorded in the data storage area is equal to or less than a specified value is treated as a group, and for this group, the data unit management information table is 2. The video information recording / reproducing method according to claim 1, wherein a group management information table for managing group information is created. In the group management information table,
Each group consists of one piece of management information, and one piece of management information includes the total data size of all the predetermined data units included in each group and the start address information of each group. 6. The video information recording / reproducing method according to claim 5, wherein one piece of management information is continuously arranged in order of recording date and time of image data of each group.   Two or more data unit management information tables having the same contents are configured on a storage medium, and a data unit management information table checksum table is provided for recording a data amount for each predetermined range of the data unit management information table. The video information recording / reproducing method according to claim 1, wherein:   Two or more group management information tables having the same contents are configured on a storage medium, and a checksum table for a group management information table for recording a data amount for each predetermined range of the group management information table is provided. The video information recording / reproducing method according to claim 1.   9. The video information recording / reproducing method according to claim 1, wherein the data unit management information table is stored in a storage medium different from a storage medium in which image data is stored.   10. The video information recording / reproducing method according to claim 5, wherein the group management information table is stored in a storage medium different from a storage medium in which image data is stored. An image input section;
Means for encoding the input image;
Data storage means for storing the encoded image data;
Image search means for searching for desired data from the stored image data;
Means for controlling reading of desired image data;
The encoded image data is continuously stored in the data storage area of the storage medium as encoded data for each predetermined data unit, and the management data area provided in an area different from the data storage area on the storage medium, A video data recording / reproducing apparatus comprising: management data generating means for creating a data unit management information table for storing management information of data recorded for each predetermined unit.   12. The management data generation means treats one or more predetermined data units continuously recorded in the data storage area as a group, and creates a group management information table for the group. The video information recording / reproducing apparatus according to 1.

Images