JP2008271414A - Stream data recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stream data recording apparatus which is capable of improving convenience of a storage medium in operation by ensuring independence of storage media of each other even when creating metadata related to text encoded data at the time retroactive from the time at which a metadata creation instruction was received. <P>SOLUTION: When free capacity in a first storage medium 9 is equal to or more than a prescribed value, a data recording section 8 records partial additional information on the first storage medium 9. When the free capacity in the first storage medium 9 is less than the prescribed value, the partial additional information is recorded on a second storage medium 10, a recording destination of text encoded data after a present recording position is switched to the second storage medium 10, and the text encoded data, recorded on the first storage medium 9, corresponding from a starting position to the present recording position are copied onto the second storage medium 10. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a stream data recording apparatus such as a video camera. In particular, the present invention relates to a recording apparatus that has a plurality of storage media and can record meta information associated with stream data when a trigger is given by a user during recording.

  Conventionally, in a video recording apparatus and an audio recording apparatus, a linear access medium such as a tape is used as a storage medium, and a photographed and recorded signal is recorded on the medium as a data stream. However, in recent years, even in handy video cameras and audio recorders, random accessible media such as semiconductor memories, hard disk drives, and optical disks are used as storage media, and the recorded information is recorded in a file format. Has become common.

  In particular, when the storage medium is detachable from the apparatus, the data capacity of the storage medium is often relatively small due to the necessity of downsizing the apparatus and the storage medium. In order to solve this problem, a method for continuously recording stream data on a plurality of storage media without interruption has been proposed (for example, described in Patent Document 1).

  The configuration disclosed in Patent Document 1 is one in which a sub disk is provided in an optical disk recording device, and recording can be continued by recording video on the sub disk while the main disk is replaced. Long-term recording is realized by sequentially switching. Further, even when the optical pickup is moving between the main disk and the sub disk, recording data such as video and audio signals of television broadcasts continuously input is recorded by the buffer memory without being lost.

  Further, using the fact that the storage medium can be accessed at random, during the recording of the stream data, additional information (metadata) associated with the time axis of the stream data is triggered by the action from the user as stream data. A method of simultaneously recording on the same storage medium is also proposed (for example, described in Patent Document 2).

  The configuration disclosed in Patent Document 2 is an image recording apparatus that records a high-definition still image on a storage medium on which a moving image is recorded when a still image release is operated during moving image shooting with a camera. In this configuration, a still image frame shooting flag is recorded at the time when a still image in the moving image file was shot, and when the flag is detected during moving image reproduction, it is recorded in another area of the storage medium. This is a method of reading out and displaying high-definition still image data.

  In the configuration disclosed in Patent Document 2, the metadata is a still image and is associated with a certain point in time of a moving image file that is stream data. However, as an application example, it is conceivable that the metadata is associated with a certain time range of the stream data.

  FIG. 10 and FIG. 11 are related to a problem in a device that simultaneously records meta information associated with a certain time range, triggered by an action from a user, in a recording apparatus capable of continuously recording stream data on a plurality of media. The description will be given with reference.

  FIG. 10 shows a general configuration of the recording apparatus. Note that the recording apparatus shown in FIG. 10 is a video camera that records video signals in two removable storage media 210 and 211.

  The recording apparatus includes a camera unit 200 (stream data acquisition unit), and the output from the camera unit 200 is branched into two, which are input to the metadata processing unit 201 and the stream processing unit 202, respectively. At this time, the video signals input to the metadata processing unit 201 and the stream processing unit 202 are the same.

  The stream processing unit 202 encodes input stream data to generate main part encoded data, and stores the generated main part encoded data in the stream buffer 204. Specific processing contents in the stream processing unit 202 include stream data down-conversion processing, video compression processing compliant with the DV standard, and video data and audio data packing processing.

  The recording device also includes an input unit 206 that receives a recording start / end instruction from the user. When the user instructs to start recording through the input unit 206, the transfer destination determination unit 208 in the data recording unit 207 determines the storage medium 208 based on information such as the remaining amount (recordable capacity) of the storage media 208 and 209. And 209 are determined. After determining the recording destination, the data transfer unit 209 reads out the main encoded data from the stream buffer 204, transfers the main encoded data to the storage medium determined by the transfer destination determining unit 208, and creates a video file.

  On the other hand, the metadata processing unit 201 processes input stream data to generate metadata (additional information), and stores the generated metadata in the metadata ring buffer 203. Specific processing contents of the metadata processing unit 201 include processing for creating video data of higher definition video than the video based on the main encoded data output from the stream processing unit 202, and compression format in the stream processing unit 202 A process of compressing a video signal in a compression format different from the above, a process of applying effects such as color conversion to input video data, and the like can be considered.

  In addition, the recording apparatus includes an input unit 205 that receives a metadata recording start instruction from the user. When recording of metadata is instructed by the user via the input unit 205, a metadata recording destination is determined using a mechanism similar to that of the main encoded data. The metadata read from the metadata ring buffer 203 is transferred to a designated storage medium, and a metadata file is created.

  FIG. 11 shows the relationship between user actions at each time point and data recorded as files, with the horizontal axis as time.

  When the user instructs the recording apparatus to start recording the main encoded data, 101, the recording of the main encoded data (main stream data) is started. For example, when the metadata creation instruction 102 is input at time t1 while recording the main encoded data, the data transfer unit 207 stores the metadata stored in the metadata ring buffer 203 based on this trigger on the storage medium 210. Or recorded in 211. At this time, the metadata read out from the metadata ring buffer 203 is read out from the metadata at time t0 that is a time Δt (first time) after time t1 and can be recorded in the storage medium 210 or 211 ( Partial additional information). Note that the maximum value of the time Δt is determined by the capacity of the metadata ring buffer 203. In this example, metadata recording continues for a certain time T (second time) from time t0, and automatically stops.

As described above, when the main encoded data and the metadata are simultaneously recorded, the remaining capacity of the main encoded data recording destination medium (assumed to be the first storage medium 210) at time t1 is the metadata data. Consider the case where it is less than the size. In that case, the recording destination of the metadata must be the storage medium that has not recorded the main encoded data at the time t1 (assumed to be the second storage medium 211).
Japanese Patent Laid-Open No. 10-106152 Japanese Patent Laid-Open No. 10-200859

  However, in the above configuration, metadata corresponding to time t0 to time t1 is stored in the second storage medium 211, and the main encoded data corresponding to time t0 to time t1 is recorded in the first storage medium 210. become. Therefore, the second storage medium 211 is in a state where there is no main encoded data regarding the time associated with the metadata even though the metadata exists. In addition, the first storage medium 210 is in a state where the metadata does not exist even though there is main encoded data that should be associated with the metadata. In this case, each of the removable first storage medium 210 and the second storage medium 211 cannot be handled independently, so that the operation of the storage medium becomes complicated and the convenience is significantly impaired.

  The object of the present invention is to ensure the independence of storage media even when creating metadata associated with the main encoded data from the time that has passed from the reception time of the metadata creation instruction. An object of the present invention is to provide a stream data recording apparatus that can improve operational convenience.

  The stream data recording apparatus of the present invention records input stream data on a plurality of storage media including a first storage medium and a second storage medium in a predetermined order, and includes a predetermined period of the stream data. A stream data recording device that generates additional information corresponding to stream data and records the additional information on any of the plurality of storage media, and encodes the input stream data to obtain main encoded data Encoding means; buffer memory for temporarily storing the main encoded data; recording means for continuously recording the main encoded data from the buffer memory to the plurality of storage media; and external input. An input unit that receives the video signal included in the stream data when the input unit receives an instruction to generate the additional information. The video signal in the period from the start position to the end position is defined as a position that is a first time later than the current recording position as a start position and a position that is a second time after the start position as an end position. Additional information generating means for generating corresponding additional information, and the recording means, when the additional information generating means generates the additional information, from the start position to the current recording position of the additional information. The partial additional information corresponding to is checked whether there is a recordable free space in the first storage medium in which the main encoded data corresponding to the current recording position from the start position is recorded, When the free capacity in the first storage medium is greater than or equal to a predetermined value, the partial additional information is recorded in the first storage medium, and the free capacity in the first storage medium is less than a predetermined value. In this case, the partial additional information is recorded on the second storage medium, the recording destination of the main encoded data after the current recording position is switched to the second storage medium, and the first storage medium The main encoded data corresponding to the current recording position is copied to the second storage medium from the start position recorded on the second storage medium.

  According to the present invention, since the independence of the storage media can be ensured even when the metadata associated with the main encoded data is created from the time that has passed from the reception time of the metadata creation instruction, The operational convenience of is improved.

  The stream data recording apparatus of the present invention can take the following various modes based on the above configuration.

  That is, in the stream data recording apparatus configured as described above, the recording unit further deletes only a portion corresponding to the current recording position from the start position from the main encoded data recorded in the first storage medium. It can be set as the structure provided with the file deletion means to do.

  In the stream data recording apparatus having the above-described configuration, the recording unit may further reproduce the main encoded data recorded by being divided into a plurality of files or a plurality of storage media as a continuous stream. Content information adding means for adding reproduction order information to the encoded data file, and the main encoded data copied to the second storage medium are recorded on the first storage medium Content information rewriting means for rewriting the reproduction order information can be provided so that the main encoded data file is reproduced with correct continuity.

(Embodiment 1)
FIG. 1 shows a configuration of a stream data recording apparatus according to the first embodiment.

  The camera unit 1 (stream data acquisition means) includes optical means such as a lens and an image sensor, converts incident optical images into electrical images, and outputs stream data. Stream data output from the camera unit 1 is input to the metadata processing unit 2 and the stream processing unit 3.

  The stream processing unit 3 (encoding means) encodes the input stream data to generate main part encoded data. The generated main encoded data is stored in the stream buffer 5. Specific processing contents in the stream processing unit 3 include video signal down-conversion processing, video compression processing compliant with the DV standard, and video data and audio data packing processing. The main encoded data stored in the stream buffer 5 is transferred to the data recording unit 8 when the input unit 7 is turned on. The input unit 7 receives a video recording start or stop operation by a user.

  The metadata processing unit 2 (additional information generating means) processes input stream data and generates metadata. The generated metadata is stored in the metadata ring buffer 4. Specific processing contents of the metadata processing unit 2 include a process of creating video data of a higher definition video than the video processed by the stream processing unit 3, and a compression format different from the compression format of the stream processing unit 3. A process of compressing a video signal, a process of applying an effect such as color conversion to the video, and the like can be considered. The metadata accumulated in the metadata ring buffer 4 is transferred to the data recording unit 8 when the input unit 6 is turned on. The input unit 6 (input means) receives an operation of a metadata addition command by a user.

  The data recording unit 8 (recording unit) includes a content data adding unit 81 (content information adding unit), a transfer destination determining unit 82, a data transfer unit 83, and a file cutout moving unit 84 (file deleting unit). Further, the file cutout moving unit 84 includes a transfer band management unit 85, a time-offset conversion unit 86, and a content data rewriting unit 87 (content information rewriting means). The data recording unit 8 performs control to record the main encoded data and metadata in the first storage medium 9 or the second storage medium 10.

  Hereinafter, the operation of the stream data recording apparatus in the present embodiment will be described. In the following description, since the remaining capacity of the first storage medium 9 is insufficient, the metadata must be recorded in the second storage medium 10, and the metadata between the storage media 9 and 10 and the main part are recorded. An operation in the case where separation of encoded data has occurred will be described. The code | symbol showing time uses what was described in FIG.

  First, a content management method in each storage medium will be described in detail.

  FIG. 2 shows the configuration of directories and files in the first storage medium 9 immediately after time t1 (see FIG. 11). FIG. 3 shows a configuration in the second storage medium 10. As shown in FIGS. 2 and 3, all the files recorded on each storage medium are stored in a CONTENTS directory 600 directly under the root directory of the storage medium. In the CONTENTS directory 600, there are a VIDEO directory 602 for storing video files, an AUDIO directory 603 for storing audio files, a CLIP directory 601 for storing CLIP data as content information, and the like. In this example, the video file 606 and the audio file 607 are stored in the MXF file format (Material eXchange Format: SMPTE 377M-2004), and the CLIP data 605 is stored in the XML file format (Extensible Markup Language: JIS X 4159: 2002). ing.

  There is always one CLIP data for one video file. Note that a plurality of audio files may exist for one video file. In the CLIP data, information relating to the association of these files is recorded. A group of files centered on one video file is referred to as a “clip” in the following description.

  FIG. 5 is an example of CLIP data 605 recorded in the first storage medium 9. The CLIP data 605 is created one by one by the content data adding unit 81 each time a new clip is created in the storage medium 9 or 10 by the recording device. CLIP data 605 is a file in which general management information related to clips such as a list of files belonging to a clip and relevance of each clip is recorded. In the example of FIG. 5, a list of files belonging to the clip in the EssenceList tag is shown. Further, as shown in the Global Clip ID tag, each clip is assigned a unique ID. This ID is used to indicate the relationship between content created by a series of continuous recordings (hereinafter referred to as shots) and recorded on a plurality of storage media. The description in the Relation tag indicates the relevance of the clips divided in a series of records. The Top tag indicates the ID of the clip corresponding to the head of a series of recordings and the serial number of the storage medium. The Previous tag indicates the immediately preceding clip. The Next tag designates the ID of the immediately following clip and the serial number of the stored storage medium. In this example, a clip managed by the CLIP file 700 recorded in the second storage medium 10 is specified by the Next tag. FIG. 6 is an example of the CLIP file 700.

  As described above, the metadata created by the trigger from the user is stored as the file 701 in the META directory 702 of the second storage medium 10 as shown in FIG. Information regarding the existence of the metadata file 701 is described in the EssenceList tag in both the CLIP file of the first storage medium 9 (see FIG. 5) and the CLIP file of the second storage medium 10 (see FIG. 6). Yes. In this example, an ID given to a shot is used as the file name of the metadata file.

  When the transfer destination determination unit 82 shown in FIG. 1 detects that the main program encoded data and the metadata related to the same time are distributed to different storage media, the main program until time t1 is sent to the file cutout moving unit 84. The location of the file belonging to the clip related to the encoded data (that is, the path of the file 605, 606, 607 shown in FIG. 2 and the serial number of the first storage medium 9), time t0, and after time t1 The location of the file belonging to the clip storing the main encoded data (that is, the path of the files 700, 703 and 704 shown in FIG. 3 and the serial number of the second storage medium 10) is notified. In the following description, the video file processing will be particularly noted and detailed. With respect to the audio file, the same processing as that of the video file described below is performed, and detailed description thereof is omitted.

  The time-offset conversion unit 86 in the file cutout moving unit 84 calculates the data start point at the time t0 in the video file 606 (see FIG. 2) based on the information on the time t0 notified from the transfer destination determination unit 82. To do. This calculation may be calculated from the data size to be recorded per unit time, or may be retrieved from the time code stored in the MXF format.

  Next, the file cutout moving unit 84 sequentially reads out the data of the video file 606 (see FIG. 2) from the file offset calculated by the time-offset conversion unit 86, and is an independent video file for the second storage medium 10. Record as. Here, the operation of recording as an independent video file is not a simple copy of the main encoded data, but the same MXF format as the video file 606 (see FIG. 2) and the video file 703 (see FIG. 3). This means that an MXF header or the like defined by the MXF format standard is added. At this time, the file cutout moving unit 84 monitors the transfer amount of the main encoded data performed by the data transfer unit 83 in the transfer band management unit 85 and does not exclude the main encoded data recording to the second storage medium 10. In addition, data is recorded using the surplus bandwidth of the second storage medium 10.

  When the file cutout moving unit 84 finishes copying all the portion of the video file 605 after the time t0 to the second storage medium 10, it creates CLIP data corresponding to the video file that has been copied, and completes the complete clip. Let

  FIG. 7 shows a file structure in the second storage medium 10 at that stage. In FIG. 7, the same files as those shown in FIGS. 5 and 6 are given the same reference numerals. As shown in FIG. 7, the content of the main encoded data after time t0 recorded in the first storage medium 9 is generated as an independent video file 501 in the second storage medium 10, and the corresponding CLIP data 500 has been generated.

  Upon confirming that the data copy to the second storage medium 10 has been completed, the file cutout moving unit 84 notifies the content data rewriting unit 87 of the completion of the content movement and the CLIP data 605 regarding the copy source video file. In addition, the location of the CLIP data 500 relating to the copy destination video file and the location of the CLIP data 700 relating to the clip currently being recorded (that is, the path name and the serial number of the recorded storage medium) are notified.

  Upon receiving the notification, the content data rewriting unit 87 rewrites the values of Previous and Next tags in the Relation tag of the CLIP data 605 and CLIP data 500 and the Previous value of the CLIP data 700. 7A and 7B show the contents of CLIP data before and after the value is rewritten. In each of FIGS. 7A and 7B, the left side in the figure is a state before rewriting, and the right side in the figure is a state after rewriting. In order to simplify the description in FIGS. 7A and 7B, XML tags and the like are described more simply than the examples shown in FIGS.

  As shown in FIG. 7A, in the CLIP data 605 related to the copy source video file, the ID indicated by Next is changed to indicate the copy destination clip. Also, as shown in FIG. 7B, the copy destination CLIP data is changed so that Previous indicates the copy source and Next indicates the clip currently in progress. At the same time, the relationship between the metadata file 701 and the copy source clip is disconnected by deleting information about the metadata from the EssenceList of the CLIP data 605.

  Next, the file cutout moving unit 84 that has received the CLIP data rewriting completion notification from the content data rewriting unit 87 deletes the portion of the video file 606 after time t0. That is, the size of the video file 606 is truncated to the offset value obtained by the time-offset conversion unit 86 until time t0.

  Hereinafter, the concept of the operation of the present embodiment will be described.

  FIG. 8 is a diagram schematically showing a process at the time of dividing the main program encoded data. FIG. 9 is a diagram schematically showing processing at the time of dividing the main encoded data in the present embodiment.

  As shown in FIG. 8, in the conventional configuration, when the remaining amount of one storage medium decreases during recording of the main stream data 22 (main-encoded data), processing for dividing the main stream data 22 is performed. The first stream data 23 and the second stream data 24 are stream data obtained by dividing the main stream data 22, and are recorded on different storage media. The first stream data 23 includes data 23a from time t11 to t12 in the main stream data 22, data 23b in the first half of data from t12 to t13, and free space 23c. The second stream data 24 is composed of data 24a from the time t13 to t14 of the main stream data 22, data 24b in the latter half of the data from the time t12 to t13, and metadata 24c.

  As shown in FIG. 8, when the main stream data 22 is divided, the stream data corresponding to the metadata 24c included in the second stream data 24 is only the data 24b which is the latter half of the data 22a, and the data 22a There is no data corresponding to the first half of. Therefore, the storage medium on which the first stream data 23 is recorded and the storage medium on which the second stream data 24 is recorded cannot be handled independently. In other words, for example, if the storage medium on which the second stream data 24 is recorded is removed from the apparatus, the data 23b in the first stream data 23 cannot be normally reproduced.

  As shown in FIG. 9, in the stream data recording apparatus of the present embodiment, the main stream data 22 is divided by the same procedure as the processing method described with reference to FIG. 25 b (the first half of the data 22 a) is copied to an empty area in the second stream data 26, and data 26 d is generated in the second stream data 26. Next, the clip information corresponding to the first stream data 25 and the second stream data 26 is rewritten so that the second stream data 26 can be normally reproduced. That is, when reproducing the divided stream data, first, the data 25a of the first stream data 25 is reproduced, then the data 26d of the second stream data 26 (the first half of the data 22a) is reproduced, and the next The clip information is rewritten so that the data 26b (the second half of the data 22a) is reproduced, and then the data 26a is reproduced. Finally, the data 25b (the first half of the data 22a) in the first stream data 25 is deleted.

  In the configuration shown in FIG. 9, since the second stream data 26 includes data 26b and 26d corresponding to the metadata 26c, the storage medium on which the second stream data 26 is recorded is temporarily removed from the apparatus. In addition, the first stream data 25 can be normally reproduced.

  As described above, according to the present embodiment, even when the metadata associated with the main encoded data is created from the time traced back from the reception time of the metadata creation instruction, the associated data are separated from each other. The storage medium can be prevented from being divided, and the independence of the storage media is ensured, so that the convenience of operation of the storage medium is improved. Further, since the relationship between the clips is also maintained, the recorded main program encoded data can be continuously reproduced.

  In this embodiment, the video file, the audio file, and the CLIP data are placed under the CONTENTS directory of the storage medium. However, the configuration on the file system is not limited to this, and the directory hierarchy and file name are not limited to this. Etc. may be freely determined by the system.

  In this embodiment, the video file and the audio file are in the MXF format, and the CLIP data is in the XML format. However, the file format is not limited to this as long as the same function is achieved. For example, the video file may be MPEG (Motion Picture Expert Group) TS (Transport Stream) or PS (Program Stream). Also, the video and audio may be multiplexed.

  In this embodiment, the continuity of the clip is described in an independent file, but this information may be recorded in a format directly embedded in a video file and an audio file.

  In the recording apparatus according to the present embodiment, the signals input to the metadata processing unit 2 and the stream processing unit 3 are the same. However, this may be a different type of signal. For example, the video signal generated by the camera unit 1 is input to the stream processing unit 3, while the output signal of an infrared camera separately provided and the output signals of various measuring devices are input to the metadata processing unit 2. Thus, the type of signal is not limited as long as data at least along the time axis is handled.

  The stream data recording apparatus according to the present invention is useful for recording video / audio data, and is particularly suitable for a system capable of simultaneously recording additional information having time information on the recorded data.

FIG. 2 is a block diagram showing a configuration of a stream data recording apparatus according to Embodiment 1. Schematic diagram showing the file structure in the first storage medium Schematic diagram showing the file structure in the second storage medium Schematic diagram showing the final file structure in the second storage medium Schematic diagram showing the contents of CLIP data stored in the first storage medium Schematic diagram showing the contents of CLIP data stored in the second storage medium Schematic diagram showing the contents of CLIP data before and after rewriting Schematic diagram showing the contents of CLIP data before and after rewriting Schematic diagram showing the configuration of conventional stream data division processing Schematic diagram showing the configuration of stream data division processing according to Embodiment 1 Block diagram showing the configuration of a conventional recording apparatus Timing chart for explaining conventional stream data division processing

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Camera part 2 Metadata processing part 3 Stream processing part 4 Metadata ring buffer 5 Stream buffer 8 Data recording part 81 Content data provision part 82 Transfer destination determination part 83 Data transfer part 84 File extraction moving part 85 Transfer band management part 86 Time -Offset conversion unit 87 Content data rewriting unit 9 First storage medium 10 Second storage medium

Claims (3)

The input stream data is recorded in a predetermined order on a plurality of storage media including the first storage medium and the second storage medium,
A stream data recording device that generates additional information corresponding to stream data of a predetermined period of the stream data and records the additional information on any of the plurality of storage media;
An encoding means for encoding the stream data to be inputted into the main encoded data;
A buffer memory for temporarily storing the main encoded data;
Recording means for continuously recording the main encoded data from the buffer memory to the plurality of storage media;
Input means for accepting external input;
When the input means receives the instruction to generate the additional information, a position that is back by a first time from the current recording position of the video signal included in the stream data is set as a start position, and a second time from the start position. An additional information generating means for generating additional information corresponding to a video signal in a period from the start position to the end position, with the position just after as the end position;
With
The recording means includes
When the additional information generating means generates the additional information, partial additional information corresponding to the additional information from the start position to the current recording position is included from the start position to the current recording position. Check whether there is a recordable free space in the first storage medium in which the main part encoded data is recorded,
When the free space in the first storage medium is a predetermined value or more, the partial additional information is recorded in the first storage medium,
When the free space in the first storage medium is less than a predetermined value, the partial additional information is recorded in the second storage medium, and the recording destination of the main encoded data after the current recording position is recorded. Stream data recording that switches to the second storage medium and copies the main encoded data corresponding to the current recording position from the start position recorded on the first storage medium to the second storage medium apparatus. The recording means further includes:
2. The stream data recording apparatus according to claim 1, further comprising: a file deleting unit that deletes only a portion corresponding to the current recording position from the start position, from the main encoded data recorded in the first storage medium. . The recording means further includes:
Content for adding reproduction order information for making it possible to reproduce the main coded data divided and recorded in a plurality of files or a plurality of storage media as a continuous stream to the coded data file Information providing means;
The reproduction order information so that the main encoded data copied to the second storage medium is reproduced with correct continuity with respect to the main encoded data file recorded on the first storage medium. The stream data recording device according to claim 1, further comprising content information rewriting means for rewriting the content information.

Images