JP2009223924A - Apparatus and method for recording and reproducing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and a method for recording and reproducing which allow efficient recording of data for recording such as image data, voice data, and other data on a recording medium and efficient reading thereof. <P>SOLUTION: The apparatus for recording and reproducing packetizes the data for recording such as encoded image data, voice data, and other data and entry data containing positional information on the video data, voice data, and other data by each predetermined data range, and consecutively records the data on the recording medium. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

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

  In a conventional video signal recording apparatus, when a video signal input from a camera or the like is recorded, a method of encoding the video signal and recording it on a recording medium such as a hard disk or an optical disk is generally used. For applications that require long-term recording, such as surveillance applications, intra-coding techniques such as JPEG (Joint Photographic Experts Group), which uses spatial redundancy within the frame to reduce the data size, A method of recording using an inter-coding technique such as MPEG (Moving Picture Expert Group) that further reduces the data size more efficiently by utilizing temporal redundancy between frames is widely used.

  When the intra coding technique is used, the data is independent for each frame and can be decoded for each frame data. On the other hand, when inter coding is used, a key frame generated by intra coding is first coded, followed by a frame coded using inter-frame correlation in the time axis direction based on the key frame, Together they form video information. For example, in the case of MPEG, first, data of an intra-coded key frame called an I frame is encoded, followed by a P frame or a B frame that is predictively encoded using correlation in the time axis direction from the I frame. The P frame is a forward predictive encoded frame using prediction from a past frame, and the B frame is a bidirectional predictive encoded frame that is predictively encoded from both the I frame and the P frame. For example, since an MPEG-encoded video has such a data structure, an I frame can be independently decoded only by the data. However, when decoding a P frame or a B frame, first, from an I frame, Must be decrypted. Also, since the data size of P frames and B frames encoded using temporal correlation is smaller than that of intra-coded I frames, the code amount for each frame is not constant. The size is indefinite for each frame.

  By the way, when recording for a long time is required, it is important how efficiently the encoded recording data is recorded on a recording medium having a finite capacity. In general, a recording medium records a data recording area in which recording data aligned (sector-aligned) in recording units is recorded, and management data for managing the recording data in the recording units. And a management data area.

  Since the recording medium is limited, in order to record a large amount of data for recording, the management data area may be reduced and the data recording area may be increased. In order to reduce the management data area, for example, the recording unit may be increased to reduce the number of recording data managed. However, if the recording data whose data size is indefinite data length is aligned in a large recording unit, there is a data recording area that is hardly recorded even if only a part is used in the alignment at the end of the recording data. It appeared and there was a problem that it was not recorded efficiently. On the other hand, if data for recording with an indefinite data length is aligned in a small recording unit, the data recording area can be used without waste, but the number of management of recording data increases. There was a problem that the size increased.

  In playback of recorded video, it is necessary to find a desired scene from the recorded video. For this reason, it is important to skip frames and play them back at high speed or play them in the reverse direction. Become. However, since inter-coded video data such as MPEG must always be decoded from an I frame, data obtained by encoding an I frame is required first. However, since the size of the recording data encoded in the P frame or B frame is not constant, it is difficult to read out the encoded data of the I frame from the recording medium at high speed.

As these improvement measures, there is a method in which a key frame is recorded for every predetermined number of video frames, and data for recording is grouped for each key frame to form a data unit (for example, Patent Document 1). In Patent Document 1, data is efficiently recorded in order to record the size of a data unit as a recording unit for alignment on a recording medium, and a track number, a zone number, and a sector are recorded in the management data area in units of data units. Data management is performed by recording address information of numbers. Also, when the compressed video and audio data are multiplexed and recorded on a disk or semiconductor memory, the start position of the GOP when the start position of the packet and the group of a plurality of recorded frames are defined as GOP (Group of Pictures) In addition, there is also a case where a management file is created by collecting the end positions of at least one intra-frame encoded frame for each GOP and recorded on the medium separately from multiplexed data (for example, patents) Reference 2).
Japanese Patent Laid-Open No. 7-87443 (page 11, FIG. 1, FIG. 6) Japanese Patent Laid-Open No. 11-261964 (page 11, FIG. 4)

  However, in the conventional technique of Patent Document 1, since data of about 1 second is collected for each data unit and the generated code amount is controlled by each compression means to perform sector alignment, code amount control processing is performed. There was a problem of increasing. In addition, since sector alignment is performed for each small unit of about 1 second, sector alignment frequently occurs, and there is a problem that the recording data area cannot be efficiently used in this portion.

  Further, in this conventional technique, address information only considers recording of data of one channel, and simultaneous recording and reproduction of a plurality of channel data generally performed for monitoring applications and the like are performed. There was a problem that was not possible.

  Furthermore, in this conventional technique, since the key frame address is described by a physical address such as a zone number or sector number, when a part of the recording data is copied to another recording medium, the speed is not increased. There was a problem that reproduction was difficult.

  In the prior art of Patent Document 2, the GOP start position, I frame position, and the like are recorded on a recording medium as a management file separate from the multiplexed data of video encoded data and audio encoded data. ing. In this case, when data is recorded without being continuously fragmented, there is a problem that a large area must be secured for the management file in advance. That is, the number of I frames generated per unit capacity of the recording medium varies greatly depending on the encoding conditions at the time of recording. For example, a large management data area is secured in anticipation of the maximum number of I frames generated. In this case, however, there is a problem in that a large management data area is not actually required depending on the set encoding condition, and in this case, there is a problem that the recording area is wasted.

  In this conventional technique, when a part of recorded data is deleted and new data is recorded in an empty area, the number of GOPs in the originally recorded data and the GOP in the newly recorded data are recorded. Since there is no guarantee that the number matches, there is a problem that it takes time to reconstruct the management data area.

  The present invention has been made to solve the above-described problems. In a recording / reproducing apparatus and a recording / reproducing method, it is possible to efficiently record indefinite-length encoded data of a plurality of channels and perform high-speed reproduction or reverse reproduction. It is intended to provide a means for enabling.

  The recording / reproducing apparatus according to the present invention assigns a header having a control information item for decoding recording data to the encoded data for recording for each predetermined data range, and has an indefinite data length. A data multiplexing unit that generates a data packet, a management information generation unit that generates management information at the time of multiplexing, a data recording area in which the data packet is recorded, and a management data area in which the management information is recorded A medium, a data recording unit that continuously records data packets generated by the data multiplexing unit in the data recording area, a management information recording unit that records management information generated by the management information generating unit in the management data area, and a header And a data extraction unit for reading out the data packet recorded in the data recording area based on the control information of the management data area and the management information of the management data area. Video data encoded with a signal, audio data encoded with an audio signal, and other data encoded with a signal other than the video signal and the audio signal, and the data packet includes video data Alternatively, it includes entry data storing data position information on the recording medium of the data packet in the audio data or other data, and the header control information specifies the data type of the data packet to which the control information is added. ID information is included.

  The recording / reproducing method according to the present invention provides a header having a control information item for decoding recording data for each predetermined data range with respect to encoded recording data, and has an indefinite data length. A data packet generating step, a management information generating step for generating management information at the time of generating the data packet, a step for continuously recording the data packet in a data recording area of the recording medium, and a management information for managing the recording medium Recording in the data area, and recording data includes video data encoded video signals, audio data encoded audio signals, and other data encoded signals other than video signals and audio signals. An entry that contains at least one of the above, and is a type of data for recording the data position of video data, audio data, or other data Based on the control information of the header, the control information of the management data area, the step of adding ID information for specifying the type of the data packet to which the control information is assigned, And a step of reading a data packet recorded in the data recording area.

  As described above, according to the recording / reproducing apparatus and the recording / reproducing method of the present invention, entry data is packetized for each predetermined data range together with data for recording, for example, encoded video data, audio data, and other data. Since recording is continuously performed on the recording medium, efficient recording with little waste is realized in the data recording area and the management data area, and the data can be read efficiently.

Embodiment 1 FIG.
FIG. 1 is a block diagram illustrating a recording / reproducing apparatus according to Embodiment 1 for carrying out the present invention. In FIG. 1, a recording / reproducing apparatus 1 includes video input units 2 and 3, video encoding units 4 and 5, an audio input unit 6, an audio encoding unit 7, a data multiplexing unit 8, and control information generation. Unit 9, management information generation unit 27, entry data generation unit 28, data recording unit 10, data storage unit 11, control information reading unit 12, management information reading unit 29, data reading unit 13, and data Separation unit 14, video decoding units 15 and 16, video output units 17 and 18, audio decoding unit 19, audio output unit 20, additional information input unit 21, additional information encoding unit 22, and additional information A decoding unit 23 and an additional information output unit 24 are provided.

  In FIG. 1, of the parts provided in the recording / reproducing apparatus 1 or directly connected to the recording / reproducing apparatus 1, those parts that do not directly affect the effects of the present invention (for example, recording by the user) Command input means for designating start and stop, status display means for displaying the status of the device, data temporary storage means for temporarily storing data in image encoding and decoding processing, and temporary The control means for controlling the stored data and the display device for displaying the output image signal) are omitted.

  A video signal output from a camera or the like is input to each of the video input units 2 and 3. In the present embodiment, a video signal of ch1 is input to the video input unit 2, a video signal of ch2 is input to the video input unit 3, and a total of two channels of video signals are input. Yes. Each of the video encoding units 4 and 5 encodes the video signal input from each of the video input units 2 and 3 to generate video data. The audio input unit 6 receives a 1ch audio signal output from a microphone or the like. The audio encoding unit 7 encodes the audio signal input from the audio input unit 6 to generate audio data. Signals other than video signals and audio signals (hereinafter, other signals) are input to the additional information input unit 21, and the additional information encoding unit 22 encodes the signals to generate other data. For example, metadata corresponds to the other data. Hereinafter, the video encoding units 4 and 5, the audio encoding unit 7, and the additional information encoding unit 22 are collectively referred to as an encoding unit.

  The management information generation unit 27 generates management information related to data recorded in the data recording area, and the entry data generation unit 28 is a part of the generated video data, audio data, or other data. Address data for the data, that is, entry data which is entry point information data is generated.

  As shown in FIG. 2, the data multiplexing unit 8 is described later with respect to the recording data 41 within a predetermined data range regardless of the type of data such as video data, audio data, other data, or entry data. An access control header 30 that is a common header having the same control information item is added to generate and multiplex a packet having an indefinite data length. The data packet 40 shown in this figure is recorded in a data recording area 11c described later.

  The recording data 41 includes at least one of the above-described video data obtained by encoding a video signal, audio data obtained by encoding an audio signal, other data, and entry data. In the present embodiment, the recording data 41 corresponds to 2-channel video data, 1-channel audio data, 1-channel other data, and entry data. Hereinafter, when the video data, the audio data, the other data, and the entry data are not distinguished, they will be referred to as recording data 41.

  The access control header 30 has the same information item regardless of whether the recording data 41 is video data, audio data, other data, or entry data. The information item of the access control header 30 includes control information 31 to 35 used for control for reading the data packet 40. The contents of the control information 31 to 35 are given by the control information generation unit 9, but may be given by the data multiplexing unit 8 without providing the control information generation unit. The access control header 30 is added to the recording data 41 for each predetermined data range, and a data packet having an indefinite data length is generated. In the following diagram, the hatched portion in the horizontal direction represents the access control header 30.

  FIG. 3 is a diagram showing a recording medium 11a provided in the data storage unit 11 and a recording area on the recording medium 11a. The recording medium 11a is the same as or corresponds to the same number in FIG. 1, and has a data recording castle 11c in which the data packet 40 is recorded. Management data for managing the data packet 40 is stored in the management data area 11b of the recording medium 11a. The data recording unit 10 of FIG. 1 continuously records the data packet generated by the data multiplexing unit 8 and the entry data generated by the entry data generating unit as the data packet 40 in the data recording area 11c of the recording medium 11a. To do.

  When reproducing the data packet 40 recorded in the data recording area 11c, the data extraction unit constituted by the management information reading unit 28, the control information reading unit 12, and the data reading unit 13 controls the control information in the access control header 30. The data packet 40 recorded in the data recording ramp 11c is read out based on the management information recorded in the management data area 11b. In the present embodiment, the control information reading unit 12 searches and reads control information that matches the desired control information from the control information of the data packet 40 recorded in the data recording area 11c. The data reading unit 13 reads the data packet 40 that matches in the control information reading unit 12.

  Of the data bucket 40 read from the data reading unit 13, the video data is sent to the video decoding units 15 and 16 by the data separation unit 14. Then, the video decoding units 15 and 16 decode the video data read by the data reading unit 13. Each of the video output units 17 and 18 outputs video data decoded by the video decoding units 15 and 16, that is, video signals. Similarly, the audio data in the data packet 40 read from the data reading unit 13 is sent to the audio decoding unit 19 by the data separation unit 14. Then, the audio decoding unit 19 decodes the audio data read by the data reading unit 13. The audio output unit 20 outputs the audio data decoded by the audio decoding unit 19, that is, the audio signal. Similarly, other data in the data packet 40 read from the data reading unit 13 is sent to the additional information decoding unit 23 by the data separation unit 14. Then, the additional information decoding unit 23 decodes the other data read by the data reading unit 13. The additional information output unit 24 outputs other data decoded by the additional information decoding unit 23, that is, other signals. Hereinafter, the video decoding units 15 and 16, the audio decoding unit 19, and the additional intelligence decoding unit 23 are collectively referred to as a decoding unit.

  In the present embodiment, it is assumed that the video encoding units 4 and 5 encode the video signal as MPEG, and the video decoding units 15 and 16 decode the MPEG encoded video data. The video data is subordinate to the I-frame video data or the I-frame video data, which is the first recording data 41 that can be independently decoded by the video decoding units 15 and 16. , 16 includes P-frame video data which is the second recording data 41 that can be decoded. The audio data can be decoded independently by the audio decoding unit 19, and the other data can be decoded independently by the additional information decoding unit 23.

  FIG. 4 is a diagram for explaining the recording method of the data packet 40 in detail. In this figure, the data recording area 11c is the same as or equivalent to that shown in FIG. Further, ch1 attached to the video data 42, 44, 46 indicates video data obtained by encoding the video signal of channel 1, and ch2 attached to the video data 43, 48 indicates the video signal of channel 2. The encoded video data is shown. In addition, (I) attached to the video data 42 and 43 indicates I frame video data that can be encoded independently, and (P) attached to the video data 44, 46, and 48 depends on the I frame. This indicates that the video data can be encoded as a P frame. Further, as the data size of each data packet 40 increases, the horizontal width of the data packet 40 in the figure is increased. In this figure, as described above, the media packets generated by the data multiplexing unit 8 are continuously recorded as data packets 40 in the data recording area 11c.

  The predetermined data range of the recording data 41 corresponds to the data size of the recording data 41. The predetermined data range is not necessarily defined by a fixed size, but is a data size defined by the encoding unit and the decoding unit. The predetermined data range is defined in, for example, the minimum data unit that can be recognized by the encoding unit and the decoding unit.

  In the present embodiment, the predetermined data range of the video data 42, 43, 44, 46, 48 is the data size when one frame of video is MPEG-encoded by the video encoding units 4 and 5. It is assumed that the data size is recognizable by the video decoding units 15 and 16 as MPEG decoded data.

  The data size of the P frame video data 44, 46, 48, that is, the predetermined data range is predictively encoded by inter-frame correlation with the I frame in the time axis direction. Different from the predetermined data range. Here, the video data 44 and 46 of the P frame of channel 1 and the video data 48 of the P frame of channel 2 are represented by the same size, but they are often different in size. Therefore, as shown in FIG. 4, the predetermined data range of the video data 42, 43, 44, 46, 48 is an indefinite data length. As a result, the data packet 40 in which the access control header 30 having a predetermined data length is added to the video data 42, 43, 44, 46, 48 has an indefinite data length.

  Although the predetermined data range of the video data has an indefinite data length, of course, a part of the predetermined data range may have a constant data size. In the present embodiment, as shown in FIG. 4, the predetermined data range of the audio data 45 and 49 is set to a constant data size, for example, about 1 KB. The predetermined data range of the other data 47 and 50 is also set to a constant data size.

  Next, control information 31 to 36 stored in the access control header 30 and reading using the control information will be described. The control information stored in the access control header 30 specifies whether the data packet 40 to which the control information is attached is video data, audio data, other data, or entry data. ID information 31 is included. The ID information 31 is assigned a unique value for each channel if, for example, video data has different channels.

  FIG. 5 shows an example of assignment of ID information 31. In this example, ID information 31 = "0x00" is the camera of channel 1, ID information 31 = "0x01" is the camera of channel 2, ID information 31 = "0x10" is the microphone of channel 1, ID information 31 ID information 31 is assigned such that “0x20” is channel 1 other data, ID information 31 = “0x40” is entry data, and ID information 31 = “0x80” is pointer data. In the present embodiment, it is assumed that the ID information 31 from “0x00” to “0xFF” expressed in hexadecimal can be assigned.

  When assigned in this way, “0x00” is given as the ID information 31 to all the data packets 40 generated from the camera image of channel 1. Similarly, “0x01” is given as the ID information 31 to all the data packets 40 generated from the camera image of the channel # 2. All data packets 40 generated from the microphone sound of channel 1 are given “0x10” as ID information 31. All data packets 40 generated from the other data of channel 1 are given “0x20” as ID information 31. All data packets 40 generated as entry data are given “0x40” as ID information 31. All data packets 40 generated as pointer data are given “0x80” as ID information 31.

  When reproducing the data packet 40, the control information reading unit 12 reads the ID information 31 of the data packet 40 that matches the desired ID information 31. If the ID information 31 matches the desired ID information 31, the data reading unit 13 reads the data packet 40 including the ID information 31 read by the control information reading unit 12. If it does not match the desired ID information 31, the control information of the next data packet 40, for example, the adjacent data packet 40, is read until the matching ID information 31 is read.

  As shown in FIG. 4, the control information of the access control header 30 includes date / time information 32 in which the data packet 40 including the control information is recorded in the data recording area 11c. When reproducing the data packet 40, the control information reading unit 12 reads the date information 32 of the data packet 40 that matches the desired date information 32. If it matches the desired date / time information 32, the data reading unit 13 reads the data packet 40 including the date / time information 32 read by the control information reading unit 12. If it does not match the desired date / time information 32, the control information of the next data packet 40, for example, the adjacent data packet 40, is read until the matching date / time information 32 is read.

  The control information of the access control header 30 includes data size information 33 of the data packet 40 including the control information. By reading the data size information 33, the control information reading unit 12 can know from which position the recording of the adjacent data packet 40 is started in the data recording area 11c.

  The control information of the access control header 30 is the position of the data packet 40 generated at the next time of the media packet including the control information among the data packets 40 including the ID information 31 that matches the ID information 31 of the control information. Is included in the forward direction pointer 34 which is address information indicating the relative position from the position of the data packet 40 including the control information. On the lower side of FIG. 6, the positions of the forward direction pointers 34 indicated by the forward direction pointers 60 to 67 of the data packets 40 are indicated by arrows.

  For example, the forward direction pointer 60 includes the ID information 31 of the video ch1 and indicates the head position of the data packet 40 generated at the next time point of the own data packet 40. The forward direction pointer 61 of the data packet 40 indicated by the forward direction pointer 60 includes the ID information 31 of the video ch1 and indicates the head position of the data packet 40 generated at the next time point of the own data packet 40. The forward direction pointer 62 of the data packet 40 indicated by the forward direction pointer 61 includes the ID information 31 of the video ch1 and indicates the head position of the data packet 40 generated at the next time point of the own data packet 40. The forward direction pointer 63 of the data packet 40 indicated by the forward direction pointer 62 includes the ID information 31 of the video ch1 and indicates the head position of the data packet 40 generated at the next time point of the own data packet 40.

  Similarly, the forward direction pointer 64 includes the ID information 31 of the video ch 2 and indicates the head position of the data packet 40 generated at the next time point of the own data packet 40. The forward direction pointers 65 and 66 include the ID information 31 of the voice ch1 and indicate the head position of the data packet 40 generated at the next time point of the own data packet 40. The forward direction pointer 67 includes the ID information 31 of entry data, and indicates the head position of the data packet 40 generated at the next time point of the own data packet 40.

  The control information of the access control header 30 is the position of the data packet 40 generated at the time before the media packet including the control information among the data packets 40 including the ID information 31 that matches the ID information 31 of the control information. Includes a backward pointer 35 which is address information indicating the relative position from the position of the data packet 40 including the control information. On the upper side of FIG. 6, the positions of the backward pointers 35 indicated by the backward pointers 70, 74, 75, 76, and 77 of each data packet 40 are indicated by arrows.

  Furthermore, in the present embodiment, the control information of the access control header 30 is the data packet 40 including the ID information 31 that matches the ID information 31 of the control information, at a time point before the media packet including the control information. It includes a backward pointer 35 that is address information indicating the position of the data packet 40 that is generated and can be independently decoded, relative to the position of the data packet 40 that includes the control information. On the upper side of FIG. 6, the positions of the backward pointers 35 indicated by the backward pointers 71 to 73 of the data packets 40 are indicated by arrows.

  As shown in FIG. 6, the backward pointers 70 to 73 of the video ch1 indicate the positions of the I frame data packet 40 that can be independently decoded from the P frame data packet 40, respectively. The backward pointer 74 of the video ch2 indicates the position of the data packet 40 generated at the previous time point, and this indicates the position of the data packet 40 of the I frame that can be independently decoded at the same time. . The backward pointers 75 and 76 of the voice indicate the position of the data packet 40 generated at the previous time point, and this indicates the position of the data packet 40 that can be independently decoded at the same time. The backward pointer 77 of the entry data indicates the position of the data packet 40 generated at the previous point in time, and this indicates the position of the data packet 40 that can be independently decoded at the same time. As described above, all the backward pointers 70 to 77 in the present embodiment indicate the head position of the data packet 40 that can be decoded independently.

  Here, the data structure of the data recording area 11c will be described with reference to FIG. As shown in FIG. 7, the data recording area 11c may include a divided data recording area 89 that is divided at regular data intervals. A pointer packet 80 is provided for each divided data recording area 89. In the present embodiment, the constant data interval is an interval that is an integral multiple of the recording unit of the recording medium 11a, and the pointer packet 80 is provided every interval that is an integral multiple of the recording unit of the recording medium 11a. Shall. In the following drawings, the hatched ones represent pointer packets 80.

  For each ID information 31 of the data packet 40 recorded in the divided data recording area 89 provided with the pointer packet 80 in the pointer packet 80, data recorded in the divided data recording area 89 and including the ID information 31 The first pointers 81 to 83 which are address information indicating the position of the data packet 40 to be read first out of the packet 40 relative to the position of the pointer packet 80 are stored. It is assumed that the data packet 40 including the ID information 31 from “0x00” to “0xFF” can be recorded in the divided data recording area 89 of the present embodiment.

  The head pointer 81 stored in the pointer packet 80 is the data packet 40 that is read first in the divided data recording area 89 provided with the pointer packet 80 among the data packets 40 whose ID information 31 is “0x00”. Indicates an address. FIG. 8 shows such a situation. The data packet 40 to which 1 is attached indicates that the data packet 40 is read first in the divided data recording area 89. The head pointer 83 stored in the pointer packet 80 is a data packet that is first read out in the divided data recording area 89 in which the pointer packet 80 is provided among the data packets 40 whose ID information 31 is “0xFF”. 40 addresses are shown. Similarly, for each ID information 31 from “0x01” to “0xFE”, a head pointer 82 indicating the address of the same data packet 40 is stored in the pointer packet 80. In this way, the address of the data packet 40 that is read first is stored for all the ID information 31. If there is no data packet 40 of the ID information 31 corresponding to the divided data recording area 89, “0” is stored as the head pointer, for example.

  Further, the pointer packet 80 is recorded in the divided data recording area 89 for each ID information 31 of the data packet 40 recorded in the divided data recording area 89 provided with the pointer packet 80. Stored are end pointers 84 to 86 which are address information indicating the position of the data packet 40 to be read last among the included data packets 40 relative to the position of the pointer packet 80.

  The end pointer 84 stored in the pointer packet 80 is that of the data packet 40 that is read last in the divided data recording area 89 provided with the pointer packet 80 among the data packets 40 whose ID information 31 is “0x00”. Indicates an address. In this figure, no. The data packet 40 with k, l, m (k, l, m are natural numbers) indicates that it is the data packet 40 read last in the divided data recording area 89. The end pointer 86 stored in the pointer packet 80 is a data packet that is read last in the divided data recording area 89 in which the pointer packet 80 is provided, among the data packets 40 whose ID information 31 is “0xFF”. 40 addresses are shown. Similarly, for each ID information 31 from “0x01” to “0xFE”, a terminal pointer 85 indicating the address of the same data packet 40 is stored in the pointer packet 80. In this way, the address of the data packet 40 that is read last is stored for all the ID information 31. When there is no corresponding data packet 40 of ID information 31 in the divided data recording area 89, for example, “0” is stored as the end pointer. Further, when there is only one piece of ID data in the divided data recording area as in the entry data in this figure, the head pointer and the terminal pointer point to the same position.

  The data size of the start pointer 81 to the start pointer 83 and the end pointer 84 to the end pointer 86 is determined by the size of the divided data recording area 89. It is assumed that a size that can be expressed relatively is secured.

  As shown in FIG. 8, the pointer packet 80 includes information on the date and time when the data packet 40 was first recorded in the divided data recording area 89 where the pointer packet 80 is provided, that is, the minimum date and time information 87 and the pointer. Information on the date and time when the data packet 40 was last recorded, that is, maximum date and time information 88 is stored in the divided data recording area 89 in which the packet 80 is provided.

  FIG. 9 shows grouping of the divided data recording areas 89 in the data recording area 11c. In the data recording area 11c, a continuous divided data recording area 89 is managed as a single group area 100 with a plurality of prescribed areas. For example, 16 divided data recording areas 89 are managed as one group. A group number is assigned along the address of the recording area 11c. A divided data recording area number is assigned to each group along the address of the recording area 11c.

  Next, FIG. 10 shows the structure of entry data. The entry data is data that stores information about an I frame that can be decoded independently. In this data, ID information, address information, and time information about the I frame are stored in time series. The ID information indicates how many channels of the camera the I frame is, and is described as 0x00 if the camera is channel 1 and 0x01 if the camera is channel 2. This corresponds to the ID information 31. The time information describes the time information at which the I frame was generated. The address information describes where the data of the I frame is stored in the data recording area 11c. This address information clearly indicates the number of the divided data recording area 89 in the group area 100 and the data position from the head in that area. This entry data packet is intended for data in each group, and is recorded as a data packet 40 in the data recording area 11c.

  In this example, I-frames that can be independently decoded are targeted as entry data. However, the present invention is not limited to this, and entry data may be configured for audio data or other data as necessary. Also good. Further, it is not necessary to register all the I frames, and the data may be constituted by thinning out such that the I frame data is targeted once every two times as necessary. Of course, they may be mixed.

  Next, FIG. 11 shows pointer information to entry data provided in the management data area. This management information indicates position information of entry data in the data recording area. This management information is generated for each group, and includes a divided data area number in the group and a relative address from the head of the divided data area. Since the data size of one group area is a fixed size and the number of groups is determined once the size of the recording medium is determined, the data size of this management information is a fixed size. By referring to this management information, it is possible to quickly know where the entry data is stored in the group area.

  The management data provided in the management data area 11b is not limited to the position information of the entry data. There is no problem even if other management information is stored simultaneously with the position information of the entry data. For example, the minimum date information and the maximum date information for each group may be stored.

  In the present embodiment, the control information reading unit 12 first reads the pointer packet 80 before reading the control information of the data packet 40. Then, when the head pointers 81 to 83 are recorded in the data packet 40 including the desired ID information 31 and reproduction is performed, the data should be read first in the divided data recording area 89 based on the information of the head pointers 81 to 83. Read the data packet 40. When the end pointers 84 to 86 are recorded in the data packet 40 including the desired ID information 31 and reverse playback is performed, the data to be read last in the divided data recording area 89 according to the information of the end pointers 84 to 86. Read the packet 40. If the data packet 40 including the desired ID information 31 is not recorded, the next pointer packet 80 is read.

  When only I pictures are selected and played back by high-speed playback or the like, first, the position of the entry data for each group recorded in the management data area is read, and the entry data is read from the data recording area 11c based on this information. The data packet 40 including the desired information is read out from the position information list of the I picture described in the entry data.

  Further, the control information reading unit 12 first reads the minimum date / time information 87 and the maximum date / time information 88 before reading the head pointers 81 to 83 and the end pointers 84 to 86. Then, it is read out whether the desired date / time is between the minimum date / time information 87 and the maximum date / time information 88. If the desired date / time is between the minimum date / time information 87 and the maximum date / time information 88, the start pointers 81 to 83 or the end pointers 84 to 86 are read out. If the desired date / time is not between the minimum date / time information 87 and the maximum date / time information 88, the next pointer packet 80 is read.

  According to the recording / reproducing apparatus 1 and the recording / reproducing method as described above, the data packet 40 is continuously recorded in the data recording area 11c of the recording medium 11a. Thereby, even if the data packet 40, that is, video data, audio data, and other data has an indefinite data length, the unused area in the data recording area 11c can be reduced. Furthermore, since entry data whose data size varies greatly depending on the data recording conditions is simultaneously multiplexed and recorded as the data packet 40, a large area for entry data can be secured in advance in the management data area as in the prior art. It becomes unnecessary and data can be efficiently recorded on the recording medium 11a.

  In addition, when recording the entry data indicating the entry position of video, audio, and other data as the packet 40 at the same time as the data, the entry position is not limited if it is always placed at the beginning of the data as in the prior art. Since it can be arranged at any position within the group area of the recording area, writing can be performed after position information such as an I frame is determined. As a result, the recording area can be used effectively, and the process of rewriting the entry data again after the data is confirmed becomes unnecessary.

  While this entry data can be arranged at any position within the group, since the position of the entry data is stored in the management information, the entry data can be quickly accessed.

  Further, by reading the pointer packet 80 before reading the data packet 40, it is possible to instantaneously search whether or not the data packet 40 including the desired ID information 31 is recorded in the corresponding divided data recording area 89. it can. Thus, when the control information reading unit 12 reads the desired control information, the desired control information can be searched efficiently, so that the data packet 40 can be read at high speed.

  Further, since the pointer packet 80 is provided at intervals of an integral multiple of the recording unit of the recording medium 11a, the pointer packet 80 can be efficiently read from the recording medium 11a.

  Further, by reading out the minimum date information 87 and the maximum date information 88, it is possible to instantly search whether or not the desired data packet 40 is recorded in the corresponding divided data recording area 89. Thus, when the control information reading unit 12 reads the desired control information, the desired control information can be searched efficiently, so that the data packet 40 can be read at high speed.

  In the first embodiment, an example is shown in which a plurality of divided data recording areas divided at regular data intervals and a group of a predetermined number of divided recording areas are provided. The number of regions and groups is not necessarily plural. When the size of the recording area is small, it may be composed of one divided recording area and one group.

Embodiment 2. FIG.
In the first embodiment, pointer packets 80 are provided in the data recording area 11c at regular data intervals in order to perform high-speed reading. For this reason, when the data packet 40 having a large data size is recorded in the area around the pointer packet 80, the data recording area 11c immediately before the pointer packet 80 may be insufficient and cannot be recorded. In such a case, the data must be recorded in the data recording area 11c of the next pointer packet 80. As a result, an area that is not recorded immediately before the pointer packet 80 is generated, and this area is wasted. This embodiment is for preventing the waste.

  FIG. 12 is a diagram for explaining the recording / reproducing apparatus 1 and the recording / reproducing method in the second embodiment for carrying out the present invention, and more specifically, a data storing method in the data recording area 11c. FIG. Note that in this embodiment, components that are the same as or correspond to the components described in Embodiment 1 are denoted by the same reference numerals.

  Video data 90 corresponds to the video data in the first embodiment. Here, the video data 90 is shown, but any recording data 41 may be used, and audio data, other data, or entry data may be used. The data multiplexing unit 8 gives each of the divided video data 91 to 93 which is a plurality of divided data generated by dividing the video data 90 which is one recording data 41 to the video data 90 before the division. The access control header 30 is added to generate a media packet. In the present embodiment, the video data 90 is divided into three parts.

  The control information of the access control header 30 includes a chain flag 36 indicating the division state. For example, when the value of the chain flag 36 is “1”, it means that the divided video data 91 is the first divided video data of the video data 90. Similarly, when the value of the chain flag is “2”, it means that the divided video data 92 is intermediate divided video data of the video data 90. When the value of the chain flag 36 is “3”, it means that the divided video data 93 is the last divided video data of the video data 90.

  In FIG. 12, “1” is described in the chain flag 36 in the access control header 30 assigned to the first divided video data 91. Similarly, “2” is described in the chain flag 36 in the access control header 30 added to the intermediate divided video data 92, and the chain flag 36 in the access control header 30 added to the final divided video data 93 is “3” is described.

  The data recording unit 10 records the data packet 40 including the chain flag 36 in an unused area of the data recording area 11 c generated immediately before the pointer packet 80. When the data packet 40 including the chain flag 36 is read in the data recording area 11c, the control information reading unit 12 reads all the data packets 40 including the corresponding chain flag 36. Then, the original video data 90 for recording is restored from the divided video data 91 to 93 included in the data packet 40.

  The recording / reproducing apparatus 1 according to the present embodiment configured as described above can record the divided video data 91 to 93 obtained by dividing the video data 90 having a predetermined data range in the data recording area 11c. Therefore, by providing the pointer packet 80 and recording the divided video data 91 to 93 in the unused area generated in the data recording area 11c before and after the pointer packet 80, the data recording area 11c is not wasted. Can be recorded efficiently. Further, even when the data packet 40 larger than the data interval of the divided data recording area 89 provided with the pointer packet 80 is recorded, the data packet 40 is recorded in the divided data recording area 89 in the same manner as described above. Can do. Further, the above configuration is not limited to a configuration for recording for a long time, and may be applied to, for example, a memory that temporarily stores and records the recording data 41 output from the encoding unit. Good. Then, even when recording data 41 having a predetermined data range that is large relative to the capacity of the memory is recorded in the memory, the memory required for the apparatus is divided and recorded. Can be substituted with a smaller memory.

  In this embodiment, an example in which one video data 90 is divided into three is shown. However, it is possible to divide the video data 90 into four or more. In this case, a plurality of pieces of data positioned in the middle are also possible. For example, 2 is described for the chain flag of the packet 40. There is no problem even if recording is performed in two parts. Further, it is not necessary to divide all the video data 90.

  In the present embodiment, the packetization of the divided data has been described on the assumption that the recording data 41 is video data. However, the recording data 41 is not limited to video data, and is not limited to video data. Data may be packetized in the same manner, and in this case, the same effect as described above can be obtained.

Embodiment 3 FIG.
FIG. 13 is a diagram for explaining the recording / reproducing apparatus 1 and the recording / reproducing method in the third embodiment for carrying out the present invention. More specifically, FIG. 13 is a diagram for explaining the data structure in the data recording area 11c. is there. Note that in this embodiment, components that are the same as or correspond to the components described in Embodiment 1 are denoted by the same reference numerals.

  S1 to S10 shown in FIG. 13 indicate the data size of each data packet 40. In the present embodiment, the data sizes S1 to S10 of the data packet 40 are configured with discrete indefinite data lengths. The discrete indefinite data length is constituted by, for example, an integer multiple of a data transfer unit (for example, 32 bytes). When the data size of the recording data 41 is not an integer multiple of 32 bytes, stuffing for data alignment is performed at the end of the recording data 41.

  The values of the data size information 33, the forward direction pointer 34, and the backward direction pointer 35 stored in the access control header 40 are expressed as values based on the 32 bytes. For example, when the size of the data packet 40 is 3072 bytes and the reference value is 32 bytes, it is expressed by a new address of 96 (= 3072/32).

  According to the recording / reproducing apparatus 1 and the recording / reproducing method as described above, the head position of the data packet 40 becomes discrete, and a range delimited by recording units can be set as a new address. In this way, the data size information 33 of the data packet 40, the forward direction pointer 34 indicating the head position of the data packet 40, and the backward direction pointer 35 can express an address with a smaller data size. It becomes. Then, by reducing the data size of the access control header 30, the recording area of the recording data 41 with respect to the access control header 30 is increased, so that it is possible to improve the recording efficiency of the recording medium 11a. This effect is the same for the start pointers 81 to 83 and the end pointers 84 to 86 of the pointer packet 80 described in the first embodiment, and the recording efficiency of the recording medium 11a can be improved. Become. Further, this effect is the same as that of the entry data address information provided in the management data area 11b described in the first embodiment, and the recording efficiency of the recording medium 11a can be improved.

Embodiment 4 FIG.
FIG. 14 is a block diagram for explaining a recording / reproducing apparatus 1 and a recording / reproducing method according to the fourth embodiment for carrying out the present invention, and more specifically, the recording / reproducing apparatus shown in the first embodiment. 1, a network receiver 25 and a network transmitter 26 are provided. Note that in this embodiment, components that are the same as or correspond to the components described in Embodiment 1 are denoted by the same reference numerals. Further, as in the first embodiment, in FIG. 14, portions that do not directly affect the effects of the present embodiment are omitted.

  A video signal output from a camera or the like is input to each of the video input units 2 and 3. In this embodiment, a two-channel video signal is input. Each of the video encoding units 4 and 5 encodes the video signal input from each of the video input units 2 and 3 to generate video data. In addition, an audio signal output from a microphone or the like is input to the audio input unit 6. The audio encoding unit 7 encodes the audio signal input from the audio input unit 6 to generate audio data. These are the same as in the first embodiment. The network receiving unit 25 is connected to an encoding device such as a network camera via a network such as a LAN. In this way, the network receiving unit 25 receives the encoded recording data 41 from the outside, for example, an external device via the network.

  The entry data generation unit 28 generates address information, that is, entry point information data for a part of the generated video data, audio data, or other data.

  The data multiplexing unit 8 assigns a common access control header 40 having the same information item to the encoded recording data 41 for each predetermined data range regardless of the type of data, and makes the data undefined. A data packet having a data length is generated and multiplexed. Here, the recording data 41 includes at least video data obtained by encoding the above-described video signal, audio data obtained by encoding an audio signal, data received by the network receiving unit 25, and entry point data. Including one. Here, the data received by the network receiving unit 25 may be video data, audio data, or other data obtained by encoding other signals other than the video signal and the audio signal.

  The management information generation unit 27 generates management information related to data recorded in the data recording area, and the entry data generation unit 28 is a part of the generated video data, audio data, or other data. Address information, i.e., entry point information data.

  The information item of the access control header 40 includes control information used for control of reading the packet medium. The contents of this control information may be given by the data multiplexing unit 8 or may be given by the control information generating unit 9. Thereafter, the data recording unit 10 continuously records the data packets generated by the data multiplexing unit 8 as data packets 40 in the data recording area 11c.

  When reproducing the data packet 40 recorded in the data recording area 11c, the data extraction unit constituted by the control information reading unit 12 and the data reading unit 14 performs data recording based on the control information in the access control header 40. The data packet 40 recorded in the area 11c is read out. In the present embodiment, the control information reading unit 12 searches and specifies control information that matches the desired control information among the control information of the data packet 40 recorded in the data recording area 11c. Further, when only I-picture data is required for high-speed playback or the like, the entry data packet position is specified based on the management information read by the management information reading unit 29, and based on the information of this entry data packet. Only the necessary I picture data is specified. The data reading unit 13 reads the data packet 40 that matches the control information and the entry data.

  The recording data 41 read from the data reading unit 13 is separated by the data separation unit 14 and sent to the video decoding units 15 and 16, sent to the audio decoding unit 19, or network transmission. Sent to the unit 26. The network transmission unit 26 transmits the data packet 40 read based on the control information to the outside, for example, an external device via the network.

  The recording / reproducing apparatus 1 according to the present embodiment having the above configuration records the data 41 for recording via the network as the data packet 40 by adding the access control header 40 in the data multiplexing unit 8. For this reason, when data at a remote location is recorded by the recording / reproducing apparatus 1, the recording data 41 recorded on the recording / reproducing apparatus 1 can be reproduced at a remote location via the network. Since the recording / reproducing apparatus 1 has the same configuration as that of the first embodiment, it has the same effect as that of the first embodiment, realizes efficient use of the data recording area 11c, and the access control header 40. By using the information and the information of the pointer packet 80, high-speed reading can be realized even in normal reproduction and special reproduction such as fast-forwarding.

  In the present embodiment, the configuration has been described in which the recording data 41 received from the network receiving unit 25 and recorded in the data recording area 11c is transmitted from the network transmitting unit 26 to the outside. However, the present invention is not limited to this, and the recording data 41 received from the network receiving unit 25 and recorded in the data recording area 11c is decoded by the decoding unit, and the video output units 17, 18 or the audio output is performed. It may be output by the unit 20. In this way, for example, the recording data 41 recorded in a remote recording device can be viewed on the recording / reproducing device 1. The recording data 41 encoded by the encoding unit of the recording / reproducing apparatus 1 and recorded in the data recording area 11c is read by the data reading unit 13 and then transmitted to the outside by the network transmission unit 26. Also good. In this way, the recording data 41 in the recording / reproducing apparatus 1 can be viewed on the remote recording / reproducing apparatus 1 via the network.

1 is a block diagram showing a recording / reproducing apparatus according to Embodiment 1. FIG. It is a figure explaining the data packet of the recording / reproducing apparatus and recording / reproducing method which concern on Embodiment 1. FIG. 2 is a diagram for explaining a recording medium of a recording / reproducing apparatus and a recording / reproducing method according to Embodiment 1. FIG. FIG. 3 is a diagram for explaining in detail a recording method of the recording / reproducing apparatus and the recording / reproducing method according to the first embodiment. It is a figure explaining ID information of the recording / reproducing apparatus and recording / reproducing method which concerns on Embodiment 1. FIG. It is a figure explaining the forward direction pointer and reverse direction pointer of the recording / reproducing apparatus and recording / reproducing method which concern on Embodiment 1. FIG. 6 is a diagram for explaining the data structure of a data recording area of the recording / reproducing apparatus and the recording / reproducing method according to Embodiment 1. FIG. It is a figure explaining the pointer packet of the recording / reproducing apparatus and recording / reproducing method which concern on Embodiment 1. FIG. 6 is a diagram for explaining grouping of divided recording areas in the recording / reproducing apparatus and the recording / reproducing method according to Embodiment 1. FIG. It is a figure explaining the structure of the entry data of the recording / reproducing apparatus and recording / reproducing method which concern on Embodiment 1. FIG. 6 is a diagram for explaining pointer information to entry data in a management data area of the recording / reproducing apparatus and recording / reproducing method according to Embodiment 1. FIG. It is a figure which shows the principal part of the recording / reproducing apparatus and recording / reproducing method which concern on Embodiment 2. FIG. It is a figure which shows the principal part of the recording / reproducing apparatus and recording / reproducing method which concern on Embodiment 3. FIG. FIG. 10 is a block diagram showing a recording / reproducing apparatus according to Embodiment 4.

Explanation of symbols

    DESCRIPTION OF SYMBOLS 1 Recording / reproducing apparatus, 2,3 Video input part, 4,5 Video encoding part, 6 Audio input part, 7 Audio encoding part, 8 Data multiplexing part, 9 Control information generation part, 10 Data recording part, 11 Data Storage section, 11a recording medium, 11b management data area, 11c data recording area, 12 control information reading section, 13 data reading section, 14 data separation section, 15, 16 video decoding section, 17, 18 video output section, 19 audio decoding Unit, 20 audio output unit, 21 additional information input unit, 22 additional information encoding unit, 23 additional information decoding unit, 24 additional information output unit, 25 network receiving unit, 26 network transmitting unit, 27 management information generating unit, 28 entries Data generation unit, 29 management information reading unit, 30 access control header, 31 ID information, 32 date and time information, 33 data size Information, 34, 60 to 67 Forward pointer, 35, 70 to 77 Reverse pointer, 36 Chain flag, 40 Data packet, 41 Data for recording, 42 Channel 1 I frame video data, 43 Channel 2 I Frame video data, 44, 46 channel 1 P frame video data, 45, 49 channel 1 audio data, 47, 50 other data, 48 channel 2 P frame video data, 51 entry data, 80 pointer packet, 81-83 start pointer, 84-86 end pointer, 87 minimum date information, 88 maximum date information, 89 divided data recording area, 90 video data, 91-93 divided video data, 100 group area.

Claims (15)

Data multiplexing for generating a data packet of indefinite data length by adding a header having a control information item for decoding the recording data to the encoded recording data for each predetermined data range A data recording area in which the data packet is recorded and a management data area in which the management information is recorded, and the data multiplexing A data recording unit that continuously records the data packets generated by the data generating unit in the data recording area, a management information recording unit that records the management information generated by the management information generating unit in the management data area, and Based on the header control information and the management data area management information, a data extraction unit that reads the data packet recorded in the data recording area,
The data packet includes at least one of video data obtained by encoding a video signal, audio data obtained by encoding an audio signal, and other data obtained by encoding a signal other than the video signal and the audio signal.
Further, the previous data packet includes entry data storing data position information on the recording medium of the data packet in the video data or the audio data or other data,
The recording / reproducing apparatus according to claim 1, wherein the control information of the header includes ID information for specifying a data type of the data packet to which the control information is added.   The recording / reproducing apparatus according to claim 1, wherein the control information items are the same regardless of the type of data.   A decoding unit that decodes the data packet read by the data extraction unit; wherein the data packet is first data for recording that can be independently decoded by the decoding unit; or It includes any of the second recording data that can be decoded by the decoding unit depending on the recording data, and stores part of the recording position information of the first recording data as entry data The recording / reproducing apparatus according to claim 1.   The control information is the relative position of the data packet generated immediately after the generation time of the data packet including the control information among the data packets including the ID information that matches the ID information of the control information. Relative to the position of the data packet generated before the generation time of the packet including the control information among the data packets including the ID information that matches the ID information of the control information. 4. The recording / reproducing apparatus according to claim 1, further comprising: address information shown in FIG. 4 and data size information of the data packet including the control information.   The data recording area includes a divided data recording area divided at regular data intervals, groups a plurality of continuous divided data recording areas, and sets one group management information as a data area for each group. 5. The recording / reproducing apparatus according to claim 1, wherein the data is stored in different management data areas.   As the group management information, ID information of data packets included in group data and position information are associated with each other and stored in the management data area, and the position information is a group number given in the order of addresses from the top of the data area, 6. The divided data recording area number assigned in the address order within the group, and address information from the start position of the divided data recording area in the divided data recording area, Recording / playback device.   7. The recording / reproducing apparatus according to claim 6, wherein ID information and position information of the entry data are stored as management information recorded in the group management information.   The data multiplexing unit generates the data packet by adding the header added to the recording data before division to each divided data generated by dividing one piece of the recording data. The recording / reproducing apparatus according to claim 1, wherein the control information includes information indicating a division state.   9. The recording / reproducing apparatus according to claim 1, wherein a data size of the data packet is discrete.   10. The recording / reproducing apparatus according to claim 1, further comprising a network receiving unit that receives the recording data from outside via a network.   The recording according to any one of claims 1 to 10, further comprising a network transmission unit that transmits the data packet read based on the management information and the control information to the outside via a network. Playback device. Adding a header having a control information item for decoding the recording data to the encoded recording data for each predetermined data range, and generating a data packet of indefinite data length; A management information generating step of generating management information at the time of data packet generation, a step of continuously recording the data packet in a data recording area of a recording medium, and a step of recording the management information in a management data area of the recording medium When,
The recording data includes at least one of video data obtained by encoding a video signal, audio data obtained by encoding an audio signal, and other data obtained by encoding a signal other than the video signal and the audio signal. Generating the data position of the video data or the audio data or the other data as entry data which is one type of the recording data;
Providing the control information with ID information for identifying the type of the data packet to which the control information is attached;
And a step of reading a data packet recorded in the data recording area based on the control information of the header and the management information of the management data area.   13. The recording / reproducing method according to claim 12, wherein the control information items are the same regardless of the type of data.   A step of decoding the data packet read based on the control information, wherein the data packet is converted into the first recordable data or the first recordable data that can be independently decoded; 13. The recording apparatus according to claim 12, further comprising any one of the second recording data that can be subordinately decoded and storing a part of recording position information of the first recording data as entry data. The recording / reproducing method described in 1. The data recording area includes a divided data recording area divided at regular data intervals, and a plurality of continuous data recording areas are grouped into one group, and one group management information is assigned to the one group. , As the group management information, the ID information and the position information of the data packet included in the group data are associated and stored in the management data area,
This position information includes a group number assigned in the order of addresses from the beginning of the data recording area, a divided data area number assigned in the order of addresses within the group, and an address from the start position of the divided data area in the divided data area. 15. The recording / reproducing method according to claim 14, further comprising a step of storing as information, wherein the group management information includes position information of the entry data.

Images