JP2008166900A - Recorder/reproducer and recording/reproducing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recorder/reproducer which can record the recording data, e.g. image data, voice data or other data, efficiently on a recording medium and can read out the data efficiently, and to provide a recording/reproducing method. <P>SOLUTION: The recorder/reproducer comprises a data multiplexing section for generating a media packet of unfixed data length by imparting a common access control header 30 having an identical information item regardless of the type of data for every predetermined data range of encoded recording data 41, 45 and 47, and a recording medium 11a having a data recording region 11c for recording a media packet. A data recording section records a media packet generated from the data multiplexing section as packet data 40 in the data recording region 11c. A data extracting section reads out the packet data 40 recorded in the data recording region 11c based on the control information 31-36 of the access control header 30. <P>COPYRIGHT: (C)2008,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 recording / reproducing apparatus, when recording a video signal input from a camera or the like, a method of recording recording data obtained by encoding the video signal on a recording medium such as a hard disk or an optical disk is generally used. For example, the following two encoding techniques are widely used when long-time recording is required as in monitoring applications. One is an intra-coding technique such as JPEG (Joint Photographic Experts Group) that reduces the data size by utilizing spatial redundancy in a frame. The remaining one is an inter-coding technique such as MPEG (Moving Picture Expert Group) that uses the temporal redundancy between frames to reduce the data size more efficiently.

  In the intra coding technique, data is independent for each frame, and decoding is possible for each frame data. On the other hand, in the inter coding technique, a key frame is first coded by intra coding, and a frame following the key frame is coded using inter-frame correlation in the time axis direction with reference to the key frame. Thus, the encoded key frame and the subsequent frame are combined to form video information. For example, when MPEG encoding is performed, first, an intra-coded key frame called an I frame is encoded, and then a P frame following the I frame or an I frame is used as a reference by using inter-frame correlation in the time axis direction. B frames are predictively encoded. The P frame is a forward predictive encoded frame that is predictively encoded from a past frame, and the B frame is a bidirectional predictive encoded frame that is predictively encoded from both an I frame and a P frame. Since MPEG-encoded video information has such a data structure, an I frame can be decoded independently only by the data, but a P frame and a B frame can be decoded independently. First, when decoding a P frame or a B frame, the I frame must first be decoded. Furthermore, P frames and B frames that have been inter-coded using the phase in the time direction have a smaller data size and a larger amount of code than I-frames that have been intra-coded. The size is an indefinite data length 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 data. For this reason, it is necessary to skip frames and play back at a high speed or 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, Patent Document 1 describes an invention in which a key frame is recorded for each predetermined number of video frames, and recording data is grouped for each key frame to form a data unit. Since the size of the data unit is recorded on the recording medium as an alignment recording unit, data is efficiently recorded. Also, in the present invention, data management is performed by recording track number, zone number, and sector number address information in the management data area in units of data units.

Japanese Patent Laid-Open No. 7-87443 (page 11, FIG. 1, FIG. 6)

  However, in the conventional technique, since data of about 1 second is collected for each data unit and then the generated code amount is controlled by each compression means to perform sector alignment, the code amount control processing increases. was there. 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.

  In the prior art, address information only considers recording of data of one channel, and data of a plurality of channels generally used for monitoring purposes cannot be recorded or reproduced at the same time. There was a problem.

  Furthermore, in the conventional technology, when performing high-speed playback, the start address for each data unit is recorded in the management table of the management area for the purpose of quickly accessing the data unit. Only the address of the unit that plays in the forward direction is shown. Therefore, there is a problem that high-speed playback in the reverse direction cannot be performed even if high-speed playback in the forward direction can be performed.

  In addition, in the conventional technology, the key frame address is described by a physical address such as a zone number or sector number. Therefore, when a part of the recorded data is copied to another recording medium, it is played back at high speed as it is. There was a problem that was difficult.

  The present invention has been made to solve the above-described problems. In a recording / reproducing apparatus and a recording / reproducing method, video data and audio data are efficiently recorded on a recording medium and efficiently read out. It is for the purpose.

  The recording / reproducing apparatus according to claim 1 of the present invention provides a common header having the same information item for each predetermined data range, regardless of the type of data, for encoded recording data. A data multiplexing unit for generating a packet having an indefinite data length, and a recording medium having a data recording area in which the packet is recorded. And a data recording unit for continuously recording the packets generated by the data multiplexing unit in the data recording area, and data for reading packet data recorded in the data recording area based on the control information of the header And an extraction unit.

  In the recording / reproducing method according to claim 14 of the present invention, a common header having the same information item is added to encoded data for recording for each predetermined data range regardless of the type of data. A step of generating a packet having an indefinite data length, and a step of continuously recording the packet in a data recording area of a recording medium. And the process of reading the packet data recorded on the said data recording area based on the control information of the said header is provided.

  According to the recording / reproducing apparatus and the recording / reproducing method of the present invention, recording data, for example, video data, audio data, and other data can be efficiently recorded on the recording medium and can be efficiently read.

<Embodiment 1>
FIG. 1 is a block diagram illustrating a recording / reproducing apparatus according to the present embodiment. The recording / reproducing apparatus 1 according to the present embodiment includes a 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, a control Information generation unit 9, data recording unit 10, data storage unit 11, control information reading unit 12, data reading unit 13, data separation unit 14, video decoding units 15 and 16, and video output unit 17 , 18, speech decoding unit 19, speech output unit 20, additional information input unit 21, additional information encoding unit 22, additional information decoding unit 23, and additional information output unit 24.

  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, stop, etc., 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 The control means for controlling the temporarily 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 1ch video signal is input to the video input unit 2, a 2ch video signal is input to the video input unit 3, and a 2-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. 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.

  As shown in FIG. 2, the data multiplexing unit 8 is a common header having the same information item regardless of the data type for each predetermined data range with respect to the encoded recording data 41. An access control header 30 is added to generate and multiplex a media packet that is a packet of indefinite data length. The packet data 40 shown in this figure is obtained by recording a media packet 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, and other data. In this embodiment, the recording data 41 corresponds to 2-channel video data, 1-channel audio data, and 1-channel other data. FIG. 2 exemplarily shows a case where the recording data 41 is video data obtained by encoding a 1ch video signal. Hereinafter, when video data, audio data, and other 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 in video data, audio data, or other data. The information item of the access control header 30 includes control information 31 to 36 used for control for reading the packet data 40. The contents of the control information 31 to 36 may be given by the data multiplexing unit 8 or may be given by the control information generating unit 9. The access control header 30 is added to the recording data 41 for each predetermined data range, and a media 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 storage area on the recording medium 11a. The recording medium 11 a is the same as or corresponds to the same number in FIG. 1 and has a data recording area 11 c in which media packets are recorded as packet data 40. Further, management data for managing the packet data 40 is stored in the management data area 11b of the recording medium 11a. The data recording unit 10 in FIG. 1 continuously records the media packets generated by the data multiplexing unit 8 as packet data 40 in the data recording area 11c of the recording medium 11a.

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

  Of the packet data 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 serving as decoding units decode the video data read by the data reading unit 13. The video output units 17 and 18 respectively output the video data decoded by the video decoding units 15 and 16, that is, video signals. Similarly, of the packet data 40 read from the data reading unit 13, the voice data is sent to the voice decoding unit 19 by the data separation unit 14. Then, the voice decoding unit 19 as a decoding unit decodes the voice 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 of the packet data 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 as a decoding unit 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 information 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 decoded according 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. It is assumed that the video data of the P frame which is the second recording data 41 that can be decoded by the conversion units 15 and 16 is included. Further, it is assumed that the audio data can be decoded independently by the audio decoding unit 19, and 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 packet data 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 packet data 40 increases, the width of the packet data 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 the packet data 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 as MPEG decoded data by the video decoding units 15 and 16.

  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 packet data 40 obtained by adding the access control header 30 having a predetermined data length 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 includes ID information 31 for specifying whether the packet data 40 to which the control information is attached is video data, audio data, or other data. Including. The ID information 31 is assigned a unique value for each channel of the recording data 41.

  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 = “0x20” is assigned ID information 31 such as “other data of channel 1”. 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 packet data 40 generated from the camera image of channel # 1. Similarly, “0x01” is given as the ID information 31 to all the packet data 40 generated from the camera image of channel # 2. All packet data 40 generated from the microphone sound of channel 1 is given “0x10” as ID information 31. All packet data 40 generated from the other data of channel 1 is given “0x20” as ID information 31.

  When reproducing the packet data 40, the control information reading unit 12 reads the ID information 31 of the packet data 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 packet data 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 packet data 40, for example, the adjacent packet data 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 packet data 40 including the control information is recorded in the data recording area 11c. When reproducing the packet data 40, the control information reading unit 12 reads the date information 32 of the packet data 40 that matches the desired date information 32. If the data matches the desired date / time information 32, the data reading unit 13 reads the packet data 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 packet data 40, for example, the adjacent packet data 40, is read until the matching date / time information 32 is read.

  The control information of the access control header 30 includes an independent / subordinate flag 36 that is information for specifying whether the packet data 40 to which the control information is attached is video data of I frame or video data of P frame.

  In the present embodiment, if the packet data 40 is an intra-coded I frame, that is, a frame that can be decoded independently, for example, “1” is given to the independent / dependent flag 36. On the other hand, if the packet data 40 is an inter-coded P frame, that is, a frame that cannot be independently significantly decoded, for example, “0” is given to the independent / subordinate flag 36. Similarly, “1” is given to the independent / subordinate flag 36 of the audio data and other data that can be significantly decoded independently.

  When generating the independent / dependent flag 36, if the information about whether independent decoding is possible or not can be acquired in the encoding unit, the control information generating unit 9 determines whether the independent / dependent flag is based on the information. Flag 36 is given. When the information cannot be acquired by the encoding unit, the control information generating unit 9 performs data analysis as to whether or not independent encoding is possible, and based on the result, the control information generating unit 9 36 is given.

  In this embodiment, audio data and other data can be significantly decoded independently. However, the present invention is not limited to this, and when independent significant decoding cannot be performed, the independent The subordinate flag 36 may be given “0”.

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

  The control information of the access control header 30 is the position of the packet data 40 generated at the next time of the media packet including the control information among the packet data 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 packet data 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 packet data 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 packet data 40 generated at the next time point of the own packet data 40. The forward direction pointer 61 of the packet data 40 indicated by the forward direction pointer 60 includes the ID information 31 of the video ch1 and indicates the head position of the packet data 40 generated at the next time point of the own packet data 40. The forward direction pointer 62 of the packet data 40 indicated by the forward direction pointer 61 includes the ID information 31 of the video ch1 and indicates the head position of the packet data 40 generated at the next time point of the own packet data 40. The forward direction pointer 63 of the packet data 40 indicated by the forward direction pointer 62 includes the ID information 31 of the video ch1 and indicates the head position of the packet data 40 generated at the next time point of the own packet data 40.

  Similarly, the forward direction pointer 64 includes the ID information 31 of the video ch2 and indicates the head position of the packet data 40 generated at the next time point of the own packet data 40. The forward direction pointers 65 and 66 include the ID information 31 of the voice ch1 and indicate the head position of the packet data 40 generated at the next time point of the own packet data 40. The forward direction pointer 67 includes the ID information 31 of other data, and indicates the head position of the packet data 40 generated at the next time point of the own packet data 40.

  The control information of the access control header 30 is the position of the packet data 40 generated at the previous time of the media packet including the control information among the packet data 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 packet data 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 the packet data 40 are indicated by arrows.

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

  As shown in FIG. 6, the backward pointers 70 to 73 of the video ch 1 indicate the positions of the I frame packet data 40 that can be independently encoded from the P frame packet data 40. The backward pointer 74 of the video ch2 indicates the position of the packet data 40 generated at the previous time point, and this indicates the position of the packet data 40 of the I frame that can be independently encoded at the same time. . The backward pointers 75 and 76 of the voice indicate the position of the packet data 40 generated at the previous time point, and this indicates the position of the packet data 40 that can be independently encoded. The backward pointer 77 of the other data indicates the position of the packet data 40 generated at the previous time point, and this indicates the position of the packet data 40 that can be independently encoded. As described above, all the backward pointers 70 to 77 in the present embodiment indicate the head position of the packet data 40 that can be encoded independently.

  When reproducing the packet data 40, the control information reading unit 12 reads the ID information 31 of the packet data 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 packet data 40 including the ID information 31 read by the control information reading unit 12. At the same time, the control information reading unit 12 reads the packet data 40 indicated by the forward direction pointer 34 or the backward direction pointer 35 and its control information in a chain. If it does not match the desired ID information 31, the control information of the next packet data 40, for example, the adjacent packet data 40, is read until the matching ID information 31 is read.

  According to the recording / reproducing apparatus 1 and the recording / reproducing method as described above, the packet data 40 is continuously recorded in the data recording area 11c of the recording medium 11a. Thereby, even if the packet data 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, so that the data can be efficiently recorded on the recording medium 11a. it can. A plurality of types of packet data 40 are managed centrally by the control information 31 to 36 of the access control header 30. Therefore, when the type of data to be read is changed, the packet data 40 that can be read in the data recording area 11c can be read without going back and forth between the management data area 11b and the data recording area 11c as in the prior art. It can be read efficiently. In particular, since data encoded simultaneously by a plurality of encoding units is recorded at positions close to each other on the recording medium 11a, the data can be efficiently read when reading a plurality of packet data 40 simultaneously. it can.

  In addition, since the ID information 31 allows the desired type of packet data 40 to be read from the data recording area 11c, it can be reproduced for each data channel and each data type.

  In addition, when performing high-speed playback, it is common to thin out several frames of video data in the time direction and perform decoding using only video data of frames that can be decoded independently. Therefore, whether or not high-speed reproduction and high-speed reverse reproduction can be performed depends on how quickly a frame that can be independently decoded can be read out. In the present embodiment, by reading the independent / subordinate flag 36, it is possible to instantaneously determine whether or not the video data can be independently decoded. Therefore, for high-speed recording required in high-speed playback. Data 41 can be read.

  If the desired ID information 31 can be read once, the position of the packet data 40 to be read next can be known in a chain by reading the forward pointer 34 and the backward pointer 35. Thereby, since quick reading is possible, high-speed reproduction or high-speed reverse reproduction can be realized. Further, since the forward direction pointer 34 and the backward direction pointer 35 relatively indicating the position of the next packet data 40 are added to the packet data 40 itself, even when a part is copied to another recording medium 11a, The same effect can be obtained.

  Further, when the desired ID information 31 can be read once when the desired ID information 31 is read, it is possible to know the position of the packet data 40 that should be read next and can be decoded independently. As a result, data that cannot be decoded independently can be thinned out efficiently, and further high-speed reverse reproduction can be realized.

  The control information of the access control header 30 includes date / time information 32 in which the packet data 40 including the control information is recorded in the data recording area 11c. With this date / time information 32, the packet data 40 recorded at a desired date / time can be easily read.

  In the present embodiment, two video encoding units 4 and 5, one audio encoding unit 7, and one additional information encoding unit 22 are provided. However, the number of encoding units is as follows. It is not limited to this. Similarly, the number of decoding units is not limited to this.

  In addition, each of the one encoding unit and one decoding unit is shown as processing a signal of one channel, but each of the one encoding unit and one decoding unit has a plurality of channels. It may be processed. For example, 4 channel videos may be encoded by one encoding unit. In this case, the same effect can be obtained by assigning different ID information 31 corresponding to each of the four channels to the recording data 41 output from one encoding unit.

  Other data other than video and audio are decoded by significant information by the additional information decoding unit 23 in FIG. 2 and output as signals from the additional information output unit 24. This signal output is directly output. It is not limited to things. For example, other data decoded by the additional information decoding unit 23 may be weighted as a video signal and output from the video output units 17 and 18.

  In addition, when the packet data 40 to be recorded on the recording medium 11a has an indefinite data length, the effect of the apparatus and method according to the present embodiment is great, but the fixed length packet data 40 is shown in the present embodiment. There is no problem even if it is recorded by the method. Furthermore, although the case where the video data is MPEG-encoded has been shown, the present invention is not limited to this, and even JPEG or other encoding scheme data can be recorded by the above-described method. For example, in the case of encoding with JPEG, the independent / subordinate flag 36 is always “1”. In this case, for example, the backward pointer 35 indicates the address immediately before the packet data 40 generated at the previous time for each ID information 31.

  Further, the recording / reproducing apparatus 1 may be configured with dedicated hardware, or may be realized by a processing means using software on a general-purpose personal computer.

<Embodiment 2>
FIG. 7 is a diagram for explaining the recording / reproducing apparatus 1 and the recording / reproducing method according to the present embodiment. More specifically, FIG. 7 is a diagram for explaining the data structure in the data recording area 11c. 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.

  As shown in FIG. 7, the data recording area 11c includes divided data recording areas 89 that are 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.

  Packets recorded in the divided data recording area 89 for each ID information 31 of the packet data 40 recorded in the divided data recording area 89 provided with the pointer packet 80 and including the ID information 31 in the pointer packet 80 In the data 40, the first pointers 81 to 83 which are address information indicating the position of the packet data 40 to be read first from the position of the pointer packet 80 are stored. It should be noted that packet data 40 including 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 packet data 40 that is first read out in the divided data recording area 89 in which the pointer packet 80 is provided among the packet data 40 whose ID information 31 is “0x00”. Indicates an address. FIG. 8 shows such a situation. The packet data 40 to which 1 is attached indicates that the packet data 40 is read first in the divided data recording area 89. The head pointer 83 stored in the pointer packet 80 is packet data that is first read out in the divided data recording area 89 in which the pointer packet 80 is provided, out of the packet data 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 packet data 40 is stored in the pointer packet 80. In this way, the address of the packet data 40 that is read first is stored for all the ID information 31. When there is no packet data 40 corresponding to the ID information 31 in the divided data recording area 89, for example, “0” is stored as the head pointer.

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

  The end pointer 84 stored in the pointer packet 80 is the packet data 40 that is read last in the divided data recording area 89 provided with the pointer packet 80 among the packet data 40 whose ID information 31 is “0x00”. Indicates an address. In this figure, no. The packet data 40 to which k, l, m, and n (k, l, m, and n are natural numbers) is the packet data 40 that is read last in the divided data recording area 89. The end pointer 86 stored in the pointer packet 80 is packet data read last in the divided data recording area 89 provided with the pointer packet 80 out of the packet data 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 packet data 40 is stored in the pointer packet 80. In this way, the address of the packet data 40 that is read last is stored for all the ID information 31. When there is no packet data 40 corresponding to the ID information 31 in the divided data recording area 89, for example, “0” is stored as the end pointer.

  The data size of the start pointer 81 to the start pointer 83 and the end pointer 84 to the end pointer 85 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.

  Further, as shown in FIG. 8, the pointer packet 80 has minimum date / time information 87 in which the packet data 40 is recorded at the first time in the divided data recording area 89 provided with the pointer packet 80, and the pointer packet 80. Is stored in the divided data recording area 89 where the packet data 40 is recorded at the last time.

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

  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 desired ID information 31 is included in the corresponding divided data recording area 89 by reading the pointer packet 80 before reading the packet data 40. Whether the packet data 40 is recorded can be instantly searched. In this way, when the control information reading unit 12 reads desired control information, the desired control information can be searched efficiently, so that the packet data 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 packet data 40 is recorded in the corresponding divided data recording area 89. In this way, when the control information reading unit 12 reads desired control information, the desired control information can be searched efficiently, so that the packet data 40 can be read at high speed.

<Embodiment 3>
In the second 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 packet data 40 having a large data size is recorded in the area before and after 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. 9 is a diagram for explaining the recording / reproducing apparatus 1 and the recording / reproducing method according to the present embodiment. More specifically, FIG. 9 is a diagram for explaining a data storing method in the data recording area 11c. Note that in this embodiment, components that are the same as or correspond to the components described in Embodiment 2 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 the recording data 41 may be used, and audio data or other data may be used. The data multiplexing unit 8 assigns the divided video data 91 to 93, which are a plurality of divided data generated by dividing the video data 90 that is one recording data 41, to the video data 90 before 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 37 indicating the division state. For example, when the value of the chain flag 37 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 37 is “3”, it means that the divided video data 93 is the last divided video data of the video data 90.

  In FIG. 9, “1” is described in the chain flag 37 in the access control header 30 assigned to the first divided video data 91. Similarly, “2” is described in the chain flag 37 in the access control header 30 added to the intermediate divided video data 92, and the chain flag 37 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 packet data 40 including the chain flag 37 in an unused area of the data recording area 11c generated immediately before the pointer packet 80. When the control information reading unit 12 reads the packet data 40 including the chain flag 37 in the data recording area 11c, the control information reading unit 12 reads all the packet data 40 including the corresponding chain flag 37. Then, the original video data 90 for recording is restored from the divided video data 91 to 93 included in the packet data 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. Furthermore, even when packet data 40 larger than the data interval of the divided data recording area 89 provided with the pointer packet 80 is recorded, the packet data 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 storing 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 the present embodiment, an example is shown in which one video data 90 is divided into three. However, it is possible to divide the video data 90 into four or more. In this case, a plurality of packets positioned in the middle are used. For example, 2 is described for the chain flag of the data 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.

  Further, in the present embodiment, the packetization of the divided data is 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 the above-described audio data or other data. Similarly, packetization may be performed, and in this case, the same effect as described above can be obtained.

<Embodiment 4>
FIG. 10 is a diagram for explaining the recording / reproducing apparatus 1 and the recording / reproducing method according to the present embodiment. More specifically, FIG. 10 is a diagram for explaining the data structure in the data recording area 11c. 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 S9 shown in FIG. 10 indicate the data sizes of the packet data 40, respectively. In the present embodiment, the data sizes S1 to S9 of the packet data 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 30 are expressed as values based on these 32 bytes. For example, when the size of the packet data 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 packet data 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 packet data 40, the forward direction pointer 34 indicating the head position of the packet data 40, and the backward direction pointer 35 can express an address with a smaller data size. Become. Then, by reducing the data size of the access control header 30, the ratio of recording the recording data 41 to the access control header 30 increases, 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 second embodiment, and the recording efficiency of the recording medium 11a can be further improved. Become.

<Embodiment 5>
FIG. 11 is a block diagram for explaining the recording / reproducing apparatus 1 and the recording / reproducing method according to the present embodiment. More specifically, in addition to the recording / reproducing apparatus 1 shown in the first embodiment, network reception Unit 25 and network transmission unit 26. 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. In addition, as in the first embodiment, in FIG. 11, 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 data multiplexing unit 8 assigns a common access control header 30 having the same information item to the encoded recording data 41 for each predetermined data range regardless of the type of data. Generate and multiplex data length media packets. Here, the recording data 41 includes at least one of the data received by the network receiver 25 in addition to the video data obtained by encoding the video signal and the audio data obtained by encoding the audio signal. Here, the data received by the network receiving unit 25 may be any of video data, audio data, video signals, and other data obtained by encoding other signals other than audio signals.

  The information item of the access control header 30 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 media packets generated by the data multiplexing unit 8 as packet data 40 in the data recording area 11c.

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

  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 It is sent to the network transmission unit 26. The network transmission unit 26 transmits the packet data 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 packet data 40 by adding the access control header 30 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 30. By using the information and the information of the pointer packet 80, high-speed reading can be realized.

  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 and 18 or the audio data is recorded. It may be output by the output 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. By doing so, 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. 1 is a diagram illustrating a recording / reproducing apparatus and a recording / reproducing method according to Embodiment 1. FIG. 1 is a diagram illustrating a recording / reproducing apparatus and a recording / reproducing method according to Embodiment 1. FIG. 1 is a diagram illustrating a recording / reproducing apparatus and a recording / reproducing method according to Embodiment 1. FIG. 1 is a diagram illustrating a recording / reproducing apparatus and a recording / reproducing method according to Embodiment 1. FIG. 1 is a diagram illustrating a recording / reproducing apparatus and a recording / reproducing method according to Embodiment 1. FIG. It is a figure which shows the recording / reproducing apparatus and recording / reproducing method which concern on Embodiment 2. FIG. It is a figure which shows the recording / reproducing apparatus and recording / reproducing method which concern on Embodiment 2. FIG. It is a figure which shows the recording / reproducing apparatus and recording / reproducing method which concern on Embodiment 3. FIG. It is a figure which shows the recording / reproducing apparatus and recording / reproducing method which concern on Embodiment 4. FIG. 10 is a block diagram showing a recording / reproducing device according to Embodiment 5;

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, 30 access control header, 31 ID information, 32 Date / time information, 33 Data size information, 34, 60 to 67 Forward pointer, 35, 70 to 77 Reverse direction poi 36, independent / subordinate flag, 37 chain flag, 40 packet data, 41 recording data, 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, 80 pointer packet, 81-83 head pointer, 84-86 end pointer, 87 minimum date and time information, 88 maximum date and time information, 89 divided data recording area, 90 video data, 91-93 divided video data.

Claims (18)

A data multiplexing unit that generates a packet of indefinite data length by adding a common header having the same information item to a predetermined data range regardless of the type of data for encoded recording data When,
A recording medium having a data recording area in which the packet is recorded;
A data recording unit for continuously recording the packets generated by the data multiplexing unit in the data recording area;
A data extraction unit for reading packet data recorded in the data recording area based on the control information of the header;
Recording / playback device. The data for recording includes at least one of video data encoded video signals, audio data encoded audio signals, and other data encoded other signals,
The control information includes ID information for specifying whether the packet data to which the control information is attached is the video data, the audio data, or the other data.
The recording / reproducing apparatus according to claim 1. A decoding unit for decoding the packet data read by the data extraction unit;
The one packet data can be decoded by the decoding unit depending on the first recording data that can be decoded independently by the decoding unit or the first recording data. Including any of the second recording data,
The control information includes information for specifying whether the packet data provided with the control information is the first recording data or the second recording data.
The recording / reproducing apparatus according to claim 2. The control information is
Data size information of the packet data including the control information;
Among the packet data including the ID information that matches the ID information of the control information, the position of the packet data generated immediately after the generation time of the packet including the control information is the packet including the control information. Address information relative to the data position;
Among the packet data including the ID information that matches the ID information of the control information, the position of the packet data generated immediately before the generation time of the packet including the control information is the packet including the control information. Including address information relative to the data position,
The recording / reproducing apparatus of Claim 2 or Claim 3. A decoding unit for decoding the packet data read by the data extraction unit;
The one packet data can be decoded by the decoding unit depending on the first recording data that can be decoded independently by the decoding unit or the first recording data. Including any of the second recording data,
The control information is
Data size information of the packet data including the control information;
Among the packet data including the ID information that matches the ID information of the control information, the position of the packet data generated immediately after the generation time of the packet including the control information is the packet including the control information. Address information relative to the data position;
Of the packet data that includes the ID information that matches the ID information of the control information, the packet data that is generated immediately before the generation time of the packet that includes the control information and includes the first recording data. Address information indicating the position relative to the position of the packet data including the control information,
The recording / reproducing apparatus according to claim 2. The data recording area is
Including a divided data recording area divided at regular data intervals;
A pointer packet provided for each of the divided data recording areas,
In the pointer packet,
For each of the ID information of the packet data recorded in the divided data recording area provided with the pointer packet, it is recorded in the divided data recording area and read out first among the packet data including the ID information. Address information indicating the position of the packet data relative to the position of the pointer packet;
For each of the ID information of the packet data recorded in the divided data recording area provided with the pointer packet, it is recorded in the divided data recording area and is finally read out of the packet data including the ID information. Storing address information indicating the position of the packet data relative to the position of the pointer packet,
The recording / reproducing apparatus according to claim 2. The fixed data interval is
The interval is an integral multiple of the recording unit of the recording medium,
The recording / reproducing apparatus according to claim 6. In the pointer packet,
The minimum date and time information in which the packet data is recorded at the first time in the divided data recording area in which the pointer packet is provided, and the packet data in the last time in the divided data recording area in which the pointer packet is provided. Stores the recorded maximum date and time information,
The recording / reproducing apparatus according to claim 6 or 7. The control information includes date and time information when the packet data including the control information is recorded in the data recording area.
The recording / reproducing apparatus according to claim 1. The data size of the packet data is discrete.
The recording / reproducing apparatus according to claim 1. The data multiplexing unit generates the packet by adding the header added to the recording data before the division to each of the divided data generated by dividing the one recording data,
The control information includes information indicating a division state.
The recording / reproducing apparatus according to claim 1. A network receiving unit for receiving the data for recording from outside via a network;
The recording / reproducing apparatus according to claim 1. A network transmission unit for transmitting the packet data read based on the control information to the outside via a network;
The recording / reproducing apparatus according to claim 1. For the encoded data for recording, for each predetermined data range, adding a common header having the same information item regardless of the type of data, and generating a packet of indefinite data length;
Continuously recording the packets in a data recording area of a recording medium;
Reading packet data recorded in the data recording area based on the control information of the header,
Recording and playback method. The data for recording includes at least one of video data encoded video signals, audio data encoded audio signals, and other data encoded other signals,
The control information includes ID information for specifying whether the packet data to which the control information is attached is the video data, the audio data, or the other data.
The recording / reproducing method according to claim 14. Further comprising the step of decoding the packet data read based on the control information,
One of the packet data is either the first recording data that can be decoded independently or the second recording data that can be decoded depending on the first recording data. Including
The control information includes information for specifying whether the packet data provided with the control information is the first recording data or the second recording data.
The recording / reproducing method according to claim 15. Further comprising the step of decoding the packet data read based on the control information,
One of the packet data is either the first recording data that can be decoded independently or the second recording data that can be decoded depending on the first recording data. Including
The control information is
Data size information of the packet data including the control information;
Among the packet data including the ID information that matches the ID information of the control information, the position of the packet data generated immediately after the generation time of the packet including the control information is the packet including the control information. Address information relative to the data position;
Of the packet data that includes the ID information that matches the ID information of the control information, the packet data that is generated immediately before the generation time of the packet that includes the control information and includes the first recording data. Address information indicating the position relative to the position of the packet data including the control information,
The recording / reproducing method according to claim 15. The data recording area is
Including a divided data recording area divided at regular data intervals;
A pointer packet provided for each of the divided data recording areas,
In the pointer packet,
For each of the ID information of the packet data recorded in the divided data recording area provided with the pointer packet, it is recorded in the divided data recording area and read out first among the packet data including the ID information. Address information indicating the position of the packet data relative to the position of the pointer packet;
For each of the ID information of the packet data recorded in the divided data recording area provided with the pointer packet, it is recorded in the divided data recording area and is finally read out of the packet data including the ID information. Storing address information indicating the position of the packet data relative to the position of the pointer packet,
The recording / reproducing method according to claim 15.

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