JP2004343167A - File recording apparatus and file recording method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a file recording apparatus and a file recording method which is adopted for a video camera for recording an imaging result by a file of e.g., the QT format to avoid a deterioration in the user-friendliness for editing work or the like to the utmost thereby recording the file of the QT format or the like for a long time even when a memory with a small capacity is in use. <P>SOLUTION: The length of a management unit corresponding to a sample of the QT file is sequentially and stepwise increased by the progress of recording of real data. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a file recording device and a file recording method, and can be applied to, for example, a video camera that records an imaging result using a QT format file. The present invention increases the length of a management unit corresponding to a sample of a QT file in a stepwise manner in accordance with the progress of actual data recording, thereby minimizing deterioration in usability in editing work and the like, and minimizing the memory capacity. , It is possible to record a file or the like in the QT format for a long time.
[0002]
[Prior art]
Conventionally, a Quick Time file format (hereinafter, referred to as a QT format) has been widely known as a file format compatible with multimedia. In recent years, an ISO Base Media file format (MPEG4-part12), Motion based on the QT format has been used as a reference. The JPEG2000 (MJ2) file format, the AVC (Advanced Video Coding: MPEG4-part10) file format, and the like are standardized.
[0003]
In this type of file format, actual data such as moving images, still images, and audio are grouped into blocks, and separately from the blocks of the actual data, management information for managing the actual data is grouped into blocks. Is done. Hereinafter, such a block is called a box, and a box in which actual data is put together is called a media data box (Media Data Box). A box in which the management information is put together is called a movie box (Movie Box).
[0004]
In this type of file format, this movie box is created by grouping management information for each attribute into a box according to a hierarchical structure, and by this movie box, a media data box held integrally and held in another file The media data box can be managed to reproduce a moving image or the like, whereby various media can be provided in a so-called internal reference format or external reference format. In such an external reference format, the media data box of another file can be managed, so that it can be used for nonlinear editing or the like.
[0005]
In this type of file format, in the media data box, real data is divided by a predetermined minimum management unit, and in a movie box, management information is stored in the lowest layer box for each of the minimum management units of the real data. Is set. Hereinafter, the minimum management unit of the actual data is referred to as a sample. Thus, in this type of file format, editing processing, cueing processing, and the like can be executed in units of this sample.
[0006]
When a file is created in this type of file format, one frame or one GOP (one GOP) corresponding to a display unit is usually considered in consideration of the convenience of processing, for example, as disclosed in JP-A-2001-94933. Group Of Pictures) is set to one sample. Although the length of one sample can be changed in one file, in order to simplify the processing, one sample is set to a fixed length in one file. I have.
[0007]
As a result, in this type of file format, the data amount of the movie box increases with the progress of the recording using the actual data, and the content of the movie box is not determined unless the recording of the actual data is completed. Thus, when recording a file on a recording medium such as a hard disk or an optical disk in this type of file format, data necessary for creating a movie box is sequentially stored in a memory or the like while sequentially recording a media data box on the recording medium. When the recording is completed and the recording of the media data box is completed, a movie box is created from the data retained in the memory or the like and recorded on the recording medium.
[0008]
[Patent Document 1]
JP 2001-94933 A
[0009]
[Problems to be solved by the invention]
By the way, when the management information whose data amount increases along with the recording of the actual data is stored in a memory or the like and recorded on a recording medium, in a device such as a computer having a memory having a sufficient capacity, a long time is required. Even when actual time data is recorded, it is possible to sufficiently cope with the case.
[0010]
However, in such a file format, it is conceivable that the present invention is applied to a portable video recorder in order to achieve compatibility with a computer. In such a portable device, a sufficient memory is required compared to a computer or the like. There is a disadvantage that it is difficult to secure the capacity.
[0011]
As a result, when recording a file in this type of file format in such a portable device, there has been a problem that recording cannot be continuously performed for a long time.
[0012]
That is, in the case of recording for a long time, the capacity of the memory is insufficient for storing the management information in the middle of recording, and even if the recording of the media data box which is the actual data can be completed correctly, It becomes difficult to correctly record the movie box that manages this, and it becomes impossible to reproduce the actual data of the media data box that has been correctly recorded. As a result, the recording is forcibly stopped in the middle of the recording, one file is created by the previous recording, and the recording is restarted again.
[0013]
Incidentally, for example, when one sample is set to one frame and video data by MPEG (Moving Picture Experts Group) is recorded for one hour, the QT format is used for time management among boxes constituting a sample table box. The data amount of the box (composition time-to-sample box) becomes about 563 [KB], and the data amount of the box (Sample Size Box) for managing the data amount of the sample becomes about 422 [KB].
[0014]
One way to solve this problem is to set the number of frames to be allocated to one sample and the length of the GOP to be long. However, there is a problem that the resolution in processing such as processing becomes coarse, and usability in processing such as non-linear editing is significantly deteriorated.
[0015]
The present invention has been made in consideration of the above points, and it is possible to avoid deterioration of usability in editing work and the like as much as possible, and to record a file or the like in the QT format for a long time even when a small capacity memory is used. A recording device and a file recording method are proposed.
[0016]
[Means for Solving the Problems]
In order to solve this problem, the invention according to claim 1 is applied to a file recording device that records sequentially input real data on a recording medium in a file of a predetermined format, and a data processing unit based on a monitoring result of the monitoring unit. Is provided with a control means for sequentially increasing the length of the management unit in a stepwise manner as the recording of actual data progresses.
[0017]
Further, according to the invention of claim 6, after the sequentially input real data is recorded on the recording medium, the management information based on the management unit sequentially set in the real data and other management information of the real data are collectively boxed in a hierarchical structure. By applying the management information box to a file recording method of recording the box on the recording medium, the length of the management unit is gradually increased step by step as the actual data is recorded.
[0018]
According to the configuration of the first aspect, if the length of the management unit is gradually increased step by step as the actual data is recorded, the memory capacity of the memory holding the management information is reduced by the recording. Accordingly, the rate of increase of the management information can be reduced and the rate of decrease of the free space can be reduced, thereby preventing the overflow of the management information in the memory. Thus, even when a small capacity memory is used, a file or the like in the QT format can be recorded for a long time. In the management information box created in this way, the management unit is initially set to a sufficient length, and the management unit becomes longer due to a decrease in the memory capacity. Can maintain the management unit as originally set. In addition, as the recording time becomes longer, the length of the management unit sequentially becomes longer at the end. As a result, it is possible to avoid as much as possible the deterioration of usability in editing work or the like due to an increase in the length of the management unit.
[0019]
Thus, according to the configuration of the sixth aspect, a file recording method capable of recording a file or the like in the QT format for a long time even when a small-capacity memory is used is provided while avoiding deterioration of usability in editing work and the like as much as possible. can do.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.
[0021]
(1) First embodiment
(1-1) Configuration of First Embodiment
(1-1-1) Overall configuration of video disk device
FIG. 2 is a block diagram showing a video disk device according to the embodiment of the present invention. In the video disk device 1, a video signal and an audio signal of a subject are obtained by an imaging unit and a voice obtaining unit (not shown), and an imaging result of the video signal and the audio signal is recorded on the optical disk 2. In addition, the imaging result recorded on the optical disk 2 is reproduced and output from a display unit using a liquid crystal display panel, an audio output unit using a speaker, and output to an external device. In the video disk device 1, after a video signal and an audio signal based on such an imaging result are data-compressed according to the MPEG format, they are recorded on the optical disk 2 in a predetermined file format. The QT format is applied to the format. In the following, a file in the QT format is called a QT file.
[0022]
Thus, in the video disk device 1, the video encoder 11 performs analog-to-digital conversion processing on the video signal DV1 based on the imaging result to generate video data, and encodes the video data according to the MPEG format. To output an elementary stream DV.
[0023]
Also, the audio encoder 12 generates audio data by performing an analog-to-digital conversion process on the audio signal DA1 based on the imaging result, encodes the audio data according to the MPEG format, and thereby outputs an elementary stream DA of the audio data. I do.
[0024]
During recording, the file generator 15 synchronizes and multiplexes the elementary streams DA and DV output from the video encoder 11 and the audio encoder 12, and creates a QT file under the control of the system control microcomputer 19. Therefore, the file generator 15 multiplexes the sequentially input elementary streams DA and DV and sequentially outputs the data of the media data box, and stores the movie box in the built-in memory 15A corresponding to the data of the media data box. The data necessary for the generation of the media data box is additionally recorded and stored, and upon completion of the recording of the media data box, a data string of the movie box is generated and output from the data stored in the memory 15A.
[0025]
The memory controller 18 switches the operation under the control of the system control microcomputer 19, and at the time of recording, sequentially records and temporarily retains the data string based on the QT file output from the file generator 15 in the memory 17, The held data is output according to the processing of the decoder 21. At the time of reproduction, on the contrary, the output data of the error correction code / decoder 21 is temporarily stored and output to the file decoder 16 and the system control microcomputer 19.
[0026]
The error correction code / decoder 21 switches its operation under the control of the system control microcomputer 19, and at the time of recording, temporarily records the output data of the memory controller 18 in the memory 20 and adds an error correction code. By reading and outputting the data held in the memory 20 in a predetermined order in this manner, the data is interleaved and output to the data modem 23. The error correction code / decoder 21 temporarily records the data output from the data modulator / demodulator 23 in the memory 20 in a predetermined order and outputs the data to the memory controller 18 in a reverse order to the time of reproduction and recording. The data output from the data modulator / demodulator 23 is deinterleaved and output. At this time, error correction processing is performed using an error correction code added during recording.
[0027]
The data modulator / demodulator 23 switches its operation under the control of the system control microcomputer 19, converts the output data of the error correction code / decoder 21 into a serial data string at the time of recording, modulates the data, and modulates the data by a magnetic field modulation driver 24 or an optical pickup. 33. At the time of reproduction, a clock is reproduced from a reproduction signal output from the optical pickup 33, and the reproduction signal is subjected to binary identification and demodulation processing with reference to this clock, whereby reproduction data corresponding to the serial data sequence generated at the time of recording is obtained. And outputs the reproduced data to the error correction code / decoder 21.
[0028]
When the optical disk 2 is a magneto-optical disk, the magnetic field modulation driver 24 drives the magnetic field head 32 by the output signal of the data modulator / demodulator 23 under the control of the system control microcomputer 19 during recording. Here, the magnetic field head 32 is held so as to face the optical pickup 33 with the optical disc 2 interposed therebetween, and applies a modulation magnetic field corresponding to the output data of the data modulator / demodulator 23 to the laser beam irradiation position of the optical pickup 33. Thus, in the video disk device 1, when the optical disk 2 is a magneto-optical disk, the imaging result is recorded on the optical disk 2 by a file in the QT format by applying a thermomagnetic recording method.
[0029]
Thus, the optical disk 2 is a disk-shaped recording medium. In this embodiment, the optical disk 2 is a rewritable optical disk such as a magneto-optical disk (MO: Magneto-Optical Disk) or a phase-change disk. Under control of the servo circuit 30, the spindle motor 31 controls the optical disk 2 according to the optical disk 2 according to the constant linear velocity (CLV), the constant angular velocity (CAV), the constant angular velocity (CAV), and the zone CLV (ZCLV: Zone Constant Linear). The optical disk 2 is rotationally driven under conditions such as Velocity).
[0030]
The servo circuit 30 controls the operation of the spindle motor 31 based on various signals output from the optical pickup 33, and thereby executes a spindle control process. Similarly, the servo circuit 30 performs tracking control and focus control of the optical pickup 33, seeks the optical pickup 33 and the magnetic field head 32, and further executes processes such as focus search.
[0031]
The drive control microcomputer 22 controls operations such as seeking in these servo circuits 30 according to an instruction from the system control microcomputer 19.
[0032]
The optical pickup 33 irradiates the optical disk 2 with a laser beam, receives the return light thereof by a predetermined light receiving element, and performs arithmetic processing on the received light to generate and output various control signals. And outputs a reproduction signal whose signal level changes in accordance with the pit row and mark row formed in the above. The optical pickup 33 switches its operation under the control of the system control microcomputer 19, and when the optical disk 2 is a magneto-optical disk, intermittently raises the amount of a laser beam applied to the optical disk 2 during recording. Thus, in the video disk device 1, an imaging result is recorded on the optical disk 2 by a so-called pulse train method. When the optical disk 2 is a phase change type disk or the like, the optical pickup 33 raises the light amount of the laser beam applied to the optical disk 2 from the light amount at the time of reproduction to the light amount at the time of writing according to the output data of the data modulator / demodulator 23. Thus, the imaging result is recorded on the optical disk 2 by applying the thermal recording method.
[0033]
Thus, in the video disk device 1, the video signal and the audio signal based on the imaging result are data-compressed by the video encoder 11 and the audio encoder 12 and converted into an elementary stream, and then the file generator 15 converts the video signal and the audio signal into a QT format file. The QT format file is recorded on the optical disk 2 by the optical pickup 33 or by the optical pickup 33 and the magnetic field head 32 through the memory controller 18, the error correction code / decoder 21, and the data modem 23 sequentially. It has been made.
[0034]
In the video disk device 1, the reproduced signal obtained from the optical pickup 33 is processed by the data modulator / demodulator 23 to obtain reproduced data, and the reproduced data is processed by the error correction code / decoder 21 and recorded on the optical disk 2. Files in the QT format can be reproduced, and data of the files in the QT format are output from the memory controller 18.
[0035]
The file decoder 16 receives the data of the QT file output from the memory controller 18, decomposes the data into elementary streams of video data and audio data, and outputs them. In this process, the file decoder 16 acquires and holds the data of the movie box in advance by the control of the seek and the like by the system control microcomputer 19, and based on the management information set in the movie box, the video data and the audio data. Output the elementary stream of.
[0036]
The video decoder 13 decompresses the elementary stream of the video data and outputs it to display means (not shown) and an external device. The audio decoder 14 decompresses the elementary stream of the audio data output from the file decoder 16 and outputs it to audio output means (not shown) and an external device. As a result, the video disk device 1 can monitor the imaging result reproduced from the optical disk 2.
[0037]
The system control microcomputer 19 is a microcomputer that controls the operation of the entire video disk device 1, and controls the operation of each unit in response to a user operation by executing a predetermined processing procedure recorded in a memory (not shown). Thereby, the system control microcomputer 19 records the imaging result on the optical disk 2, reproduces the imaging result recorded on the optical disk 2 and provides the reproduction result to the user, and further executes the editing process. In the control of each unit related to such recording, the system control microcomputer 19 switches the settings of the file generator 15 so as to sequentially switch the setting of one sample in accordance with the progress of recording, thereby effectively reducing the usability in editing work and the like. Thus, the imaging result can be recorded for a long time even when a small capacity memory is used.
[0038]
(1-1-2) QT file
Here, FIG. 3 is a conceptual diagram showing a basic configuration of the QT file. The QT format is a file format created as an extended function of an OS (Operating System) for reproducing a moving image or the like without using special hardware. The QT format is a time-based multimedia file format in which real data in various formats such as moving images, audio, still images, characters, and MIDI can be reproduced in a synchronized manner on one time axis. It is made to be able to cope with. In the QT file, the actual data in these various formats is stored as individual tracks, and the actual data tracks of moving images, sounds, and characters are respectively referred to as video tracks, sound tracks (audio tracks), and text tracks. It has been made.
[0039]
In the QT files F1 and F2, a set of the tracks forms a media data box (Media Data Box), and management information of each track of the media data box (Media Data Box) is put together to form a movie box (Movie Box). Is formed. Here, the box is also called an atom. The type name of the media data box is set to mdat, and is also called movie data (Movie Data). On the other hand, the movie box has a box type name set to moov, and is also called a movie resource (Movie Resource).
[0040]
The QT file includes a self-contained file F1 having a format in which the media data box and the movie box are integrated, and an external reference file F2 having only the movie box. In the external reference file F2, A media data box existing in another file F1 can be set as a management target, so that it can be used for non-linear editing or the like. When the media data box existing in the other file F1 is to be managed as described above, management information such as a relative path and an absolute path on the recording medium for the other file is also assigned to the movie box. It has been made to be.
[0041]
FIG. 4 is a table showing the media data box and the movie box in detail when the media data box is constituted by the video track and the audio track with respect to the self-contained file F1. FIGS. 5 is a chart showing the configuration of FIG. 4 together with type names in C language description. In the movie box, the description of the track box (type name trak) for the lower layer of the track box related to the audio track is omitted in FIG. 4 because the box structure of the lower layer is almost the same for the video track and the audio track. Shown.
[0042]
Movie boxes are created in a hierarchical structure in which management information is boxed for each attribute. That is, the movie box is configured by a movie header box (movie header), a track box (track), and the like. The movie header box contains header information, and the type name is set to mvhd. On the other hand, the track boxes (track) are provided corresponding to the tracks provided in the media data box. The track box (track) is composed of a track header box (track header), an edit box (edit), a media box (media), and the like, and describes information on individual actual data in the media data box.
[0043]
Here, a track header box (track header) contains header information. The edit box (edit) includes an edit list box (edit list) as necessary, and by setting information such as time information up to an in point and an out point, reproduction speed, and the like in the edit list box (edit list). Has been made available for non-linear editing.
[0044]
In the media box (media), information for managing the compression method, storage location, display time, and the like of the corresponding real data is assigned, and the type name is set to mdia. The media box (media) is composed of a media header box (media header), a media handler reference box (media handler reference), and a media information box (media information). Here, a media header box (media header) is assigned header information, and a media handler reference box (media handler reference (indicated by media handler in FIG. 4)) records the type of the corresponding real data. Video data, audio data, and the like can be identified.
[0045]
In the media information box (media information), various types of information relating to the sample, which is the minimum management unit, are assigned, and the type name is set to minf. The media information box (media information) includes a media header (video media information header, sound media information header (indicated by a video media header in FIG. 4) corresponding to actual data), and a data handler reference box (representing a header field). , Data handler), a data information box (data information), and a sample table box (sample table).
[0046]
Here, the type of the media header is set to vmhd and smhd in the video track and the audio track, respectively, corresponding to the upper media handler reference box (media handler reference), and the header information is stored. In the data handler reference box (data handler reference), information relating to the handling of the corresponding real data is set, and in the data information box (data information), data actually referred to by the lower-level data reference box (data reference) is stored. Information on the location and storage method is assigned.
[0047]
In the sample table box (sample table), information about each sample is assigned, and the type name is set to stbl. The sample table box (sample table) includes a sample description box (sample description), a time sample box (time-to-sample), a sample size box (sample size), a sample chunk box (sample-to-chunk), and a chunk offset. It comprises a box (chunk offset), a synchronous sample box (sync sample), a composition time sample box (composition time-to-sample), and the like.
[0048]
Here, in the sample description box (sample description), information on decoding is stored, and specifically, a data compression method and related information are assigned. That is, as shown in FIG. 7, the sample description box (sample description) is sequentially assigned a size (Size), a type name (stsd), a version, and a flag of the sample description box (sample description). Also, the number of entries (number of Entries) of the sample description box (sample description) is allocated, and an entry (Video sample description entry) based on the data compression method and related information is allocated by the number of entries.
[0049]
In the sample description box (sample description), these entries (Video sample description entry) are registered, and the number of entries (number of entry entries) is registered in response to a change in the processing of the actual data related to this entry (Video sample description entry). Is counted up. The sample description box (sample description) is provided with a field (Frame Count) for describing the number of frames to be allocated to one sample in one of the entries (Video sample description entry), and the number of frames of one sample is provided in this field. It is made to record it. Specifically, when one GOP is defined as one sample, 15 frames are described in this field. When two GOPs are defined as one sample, 30 frames are described in this field. By the way, the entry (Video sample description entry) related to such a change of the processing has the entry number in the index number (sample description Index) set in the entry of the sample chunk box (sample-to-chunk) described later. Corresponding settings are made so that a change in the corresponding process in the actual data can be detected.
[0050]
Accordingly, in the sample description box (sample description), even if the data amount of the media data box increases due to the progress of recording, the data amount is held at a constant value, but the frame allocated to one sample in the middle When the number is changed, the data amount is increased by one entry.
[0051]
In a time sample box (time-to-sample), a relationship between each sample and a time axis related to decoding is described by a frame rate. That is, as shown in FIG. 8, a time sample box (time-to-sample) is sequentially assigned a size (Size), a type name (stts), a version, and a flag of the time sample box (time-to-sample). The number of entries (number of entries) is assigned, and the entries (Time-to-Sample entries # 1 to #M) are registered by the number of entries. The time sample box (time-to-sample) includes a display time (Sample Duration) of one sample and a number of samples (Sample) to which the display time is applied to this entry (Time-to-Sample entry # 1 to #M). Count) is assigned. Thus, in a QT file, for example, when video signals of different frame rates are recorded by one file according to the NTSC system or the PAL system, the time sample box (time-to-sample) can be reproduced without discomfort. It has been made. In this embodiment, the time sample box (time-to-sample) is held at a constant data amount even when the data amount of the media data box increases due to the progress of recording.
[0052]
On the other hand, when the number of frames allocated to one sample is changed, the display time (Sample Duration) differs due to the change in the display time per sample. Thereby, in this case, an entry (Time-to-Sample entry) is added to the time sample box (time-to-sample), and the number of entries (number of Entries) is up-counted. Thus, when the number of frames assigned to one sample is changed during recording, the data amount of the time sample box (time-to-sample) is increased by one entry.
[0053]
The sample size box (sample size) describes the data amount of each sample. That is, as shown in detail in FIG. 9, the sample size box (sample size) is sequentially assigned the size (Size), the type name (stsz), the version, and the flag of the sample size box (sample size). The length (Default Sample Size value) is recorded. If even one sample size is different, the number of entries (Number of Entries) is described by a value corresponding to the number of samples, and the size (Sample Size value) of each sample is represented by an entry (Sample Size entry # 1 to #N). ). In the sample size box (sample size), this one entry (Sample Size entry) is described by 4 [Byte] having a fixed length, and this entry is provided for each sample in the actual data. Accordingly, in the sample size box (sample size), as the number of samples in the media data box increases due to the progress of recording, the number of entries (Number of Entries) and the entries (Sample Size entries # 1 to #N) increase accordingly. Thus, the data amount is increased.
[0054]
The sample chunk box (sample-to-chunk) describes the relationship between a chunk (chunk) and the samples that make up the chunk (chunk). Here, a chunk is a block when each track data is divided into blocks and assigned to a media data box, and one chunk is created by a set of a plurality of samples. In the sample chunk box (sample-to-chunk), a size (Size), a type name (stsc), a version, and a flag of the sample chunk box (sample-to-chunk) are sequentially assigned, the number of entries (Number of Entries), Entries (Sample-to-Chunk entry # 1 to Sample-to-Chunk entry #M) are described. Here, each time the number of samples constituting one chunk is changed, an entry (Sample-to-Chunk entry) is registered in the sample chunk box (Sample-to-Chunk), and this entry (Sample-to-Chunk) is registered. The first chunk number (First Chunk Number) related to the entry, the number of samples per chunk (Sample per Chunk), and the like are assigned to the entry.
[0055]
When the number of frames allocated to one sample is changed during recording, the sample chunk box (sample-to-chunk) corresponds to the addition of an entry in the sample description box (sample description) described above. Chunk entry) is added, and the entry of the corresponding sample description box (sample description) can be specified by the index number (sample description Index) of this entry. As a result, the sample chunk box (sample-to-chunk) is kept at a fixed data amount even if the number of samples in the media data box increases due to the progress of recording. When the number is changed, the data amount is increased by one entry.
[0056]
In the chunk offset box (chunk offset), position information of the beginning of each chunk based on the beginning of the file is recorded by an entry. As a result, in the chunk offset box, as the number of chunks in the media data box increases due to the progress of recording, the data amount increases in the same manner as in the sample size box (sample size). I have.
[0057]
The synchronization sample box (sync sample) and the composition time sample box (composition time-to-sample) are optional. In the synchronous sample box (sync sample), the position information of the I picture in the sample is described in the form of a table, and in the composition time sample box (composition time-to-sample), the order on the stream and the display on the stream are determined by data compression processing. , The time information related to the display is recorded. Accordingly, in the composition time-to-sample, as the number of samples in the media data box increases as recording progresses, the data amount increases accordingly. In this embodiment, by setting one sample in GOP units, these synchronous sample boxes (sync samples) are omitted.
[0058]
The audio track does not require the rearrangement of decoding results as in the case of the video track, so that a composition time-to-sample is omitted, and data is compressed at a fixed rate. Thus, although the data amount increases due to an increase in the number of samples due to the progress of recording, the degree of the increase is smaller than that of the video track.
[0059]
Thus, in the sample table box, the management information of the sample, which is the minimum management unit, is boxed for each attribute. In these boxes, a sample size box (sample size), a chunk offset box (chunk offset), and a synchronous sample box ( Sync sample) and composition time-to-sample are assigned management information whose data amount increases in accordance with the data amount of actual data due to the progress of recording. In particular, in a sample size box (sample size), a synchronous sample box (sync sample), and a composition time sample box (composition time-to-sample), data is set according to the number of samples which is the minimum management unit due to the progress of recording. Management information is assigned by a management unit whose amount increases. On the other hand, in the sample description box (sample description), the time sample box (time-to-sample), and the sample chunk box (sample-to-chunk), as in the other boxes of the sample table box, the actual data is stored. The management information required for the processing is allocated, and every time a parameter constituting the management information is changed, the changed management information is provided by the entry.
[0060]
On the other hand, in the media data box, elementary streams of video data and audio data, which are actual data of a QT file, are respectively assigned to chunks as a set of samples, and chunks and audios by the elementary streams of video data are assigned. Chunks based on elementary streams of data are provided alternately.
[0061]
In this embodiment, the audio encoder 12 and the video encoder 11 use the MPEG1 Audio Layer 2 compression encoding system to encode these audio data and video data elementary streams into audio data and MPEG2 Video compression code. Video data encoded according to a coding scheme is applied. In the QT file, various video data such as Motion JPEG, Motion JPEG2000, MPEG4, and AVC, and various audio data such as Dolby AC3 and ATRAC (Adaptive Transform Acoustic Coding) are applied to these audio data and video data. It is also possible to use linear data that has not been subjected to any compression encoding processing.
[0062]
FIG. 11 shows an example of video data having a frame rate of 30 [frames / second] with respect to data DQ of a QT file in such a media data box and a movie box. 6 is a time chart showing a relationship between a frame, a sample, and a chunk in comparison with an elementary stream DV. In the QT file, as described above, the minimum management unit is set to a sample, and a chunk is created by a set of the samples, so that one GOP (15 video frames) is set to one sample, and two samples are set to one chunk. (FIGS. 11A and 11B), one chunk is set per second, and the actual data of the elementary stream DV of the video data is sequentially managed. In FIG. 11, SH is a sequence header in the elementary stream DV. As a result, in the QT file, the actual data can be decoded by directly accessing the sample unit. In such a setting, it is desirable to apply a so-called closed GOP in which a predicted frame is set in the GOP.
[0063]
On the other hand, FIG. 12 shows an example in which sampling data of 48 [kHz] and two-channel audio data are used to compare frames, samples, and audio data output from the audio encoder 12 with the elementary stream DA. 6 is a time chart showing a relationship between chunks. In this case, in the audio data DA output from the audio encoder 12 (FIG. 12A), an audio decode unit as a decoding unit is set by 1152 samples × 2 channels. When the audio decoding unit is set to one sample for such audio data, and one chunk is set to one second in correspondence with the chunk setting in the video data shown in FIG. Are 41.66... Samples. Thereby, in this case, 41 samples, 42 samples, and 42 samples are allocated to three consecutive chunks, respectively, and the file generator 15 multiplexes video data and audio data in units of three chunks (see FIG. B)). As a result, in the QT file, even for audio data, actual data can be directly accessed and decoded in sample units.
[0064]
FIGS. 13 and 14 are time charts showing the relationship between interleaving and chunks for such video data and audio data. In the example shown in FIG. 13, a video signal DV1 having a frame rate based on a frame period t0 is input to the video encoder 11, and one GOP of video data DV obtained by encoding the video signal DV1 is set to one sample. It is. In this case, four samples are allocated to one chunk with respect to the sample based on one GOP, and interleaved with audio data in chunk units. The head of each chunk is detected by the above-described chunk offset box (chunk offset).
[0065]
On the other hand, as shown in FIG. 14, for the audio signal DA1, one audio decoding unit is assigned to one sample, and one chunk is constituted by a plurality of samples so as to correspond to an interleave unit in the video data. The video data is interleaved.
[0066]
FIGS. 15 to 17 are schematic diagrams for explaining the layout of the chunks set as described above on the optical disc 2. When a QT file having such a configuration is recorded on the optical disk 2 on which no file is recorded, data of the media data box is sequentially recorded in a continuous area first, and when the recording of the media data box is completed, the corresponding data is recorded. The movie box data is sequentially recorded in a continuous area, whereby the QT file is recorded in a continuous area as if by a single stroke.
[0067]
On the other hand, when recording and deletion of a file on the optical disk 2 are repeated, fragments are advanced on the optical disk 2 and it becomes difficult to record a QT file in a continuous area. FIGS. 15 to 17 show the layout of a QT file in such a case. FIG. 15 shows a QT file having one track structure as an example and records the QT file in at least a continuous area in chunk units. To improve accessibility. FIGS. 16 and 17 show an example of a QT file having a track structure of audio and video data, and improve the accessibility by recording the QT file in a continuous area at least in units of corresponding chunks of audio and video data. Things.
[0068]
(1-1-3) QT file processing
Accordingly, in the video disk device 1, the file generator 15 stores the sample as the minimum management unit and the chunk as the upper management unit of the sample in the elementary streams DV and DA based on the video data and the audio data as the actual data. While sequentially setting, multiplexing the elementary streams DV and DA and recording them by the recording means, the management information is sequentially acquired corresponding to the recording of the actual data and held in the memory 15A. According to the management information held in the memory 15A, the data of the movie box, which is a box of the management information, is output to the recording means, and constitutes a data processing means for these processes.
[0069]
The file generator 15 executes such setting of the management unit under the control of the system control microcomputer 19. That is, the file generator 15 sets the length of one sample for the video data and sets the number of samples constituting one chunk and the like according to the instruction of the system control microcomputer 19. The file generator 15 sets the length of one sample for the audio data as described above with reference to FIGS. 11 to 17 corresponding to the setting of one sample and one chunk for the video data. Set the number of samples to be configured.
[0070]
In response to the processing of the file generator 15, the system control microcomputer 19 instructs each circuit block including the file generator 15 to start and end recording of the imaging result in response to the operation of the trigger switch by the user. In this embodiment, the process from the start to the end of recording according to this instruction is recorded on the optical disc 2 as one QT file. In this case, the result of the repeated operation of the trigger switch may be recorded on the optical disc 2 by splicing, and the recording from power-on to power-down may be a single QT file.
[0071]
Thus, in the video disk device 1, the file generator 15 sequentially processes the elementary streams of the video data and the audio data to record the media data box on the optical disk 2, and stores the data necessary for constructing the movie box in the memory 15A. When the recording of the media data box is completed under the control of the system control microcomputer 19, the movie box is recorded on the optical disc 2 by the data accumulated in the memory 15A, and one QT file is recorded on the optical disc 2 by these. It has been made to be.
[0072]
When instructing the start of recording of the imaging result in this way, the system control microcomputer 19 instructs the file generator 15 to set the length of one sample to one GOP. When recording is started, the free space M of the memory 15A held in the file generator 15 is monitored, and the processing procedure of FIGS. 1 and 18 is executed. To be increased step by step. Thus, in this embodiment, even when recording is performed for a long time, the capacity of the memory 15A is not insufficient, and the QT file can be recorded for a long time even when a memory having a small capacity is used.
[0073]
That is, the system control microcomputer 19 moves from step SP1 to step SP2 in response to a recording start instruction from the user, instructs the file generator 15 to set the length of one sample to 1 GOP, and then records the data in each circuit block. Start is instructed, thereby starting recording of the media data box. Thus, in step SP3, the system control microcomputer 19 sequentially stores management information necessary for the movie box in the memory 15A while setting one sample to 1 GOP and recording the media box on the optical disc 2.
[0074]
When the recording is started in this manner, the system control microcomputer 19 determines whether or not the end of the recording is instructed by the operation of the trigger operator by the user in a succeeding step SP4. Moving to SP5, it is determined whether or not the free space M of the memory 15A is equal to or less than 1/2 of the capacity of the memory 15A. If a negative result is obtained here, the system control microcomputer 19 returns to step SP3. Thereby, the system control microcomputer 19 repeats the processing procedure of step SP3-step SP4-step SP5-step SP3 until the free space M of the memory 15A becomes equal to or less than 1/2 of the capacity of the memory 15A, and one sample. Is set to 1 GOP, and the imaging result is recorded on the optical disc 2. On the way, if a positive result is obtained in step SP4 by the operation of the trigger switch by the user, the process moves from step SP4 to step SP6, and instructs the file generator 15 or the like to end the recording, thereby recording the media data box. After completion, a movie box is generated from the management information stored in the memory 15A and recorded on the optical disc 2. When the recording of the movie box is completed, the process moves to step SP7, and the processing procedure ends.
[0075]
Thus, in the video disk device 1, for a file having a relatively short time, one sample is set to one GOP and recorded on the optical disk 2, thereby effectively avoiding deterioration in usability in editing processing and the like. .
[0076]
On the other hand, in this way, one sample is set to 1 GOP and the media data box is recorded. When the free space M of the memory 15A becomes equal to or less than の of the capacity of the memory 15A due to the progress of the recording, step SP5 Is obtained, the system control microcomputer 19 proceeds from step SP5 to step SP8. Here, the system control microcomputer 19 instructs the file generator 15 to set one sample to 2 GOPs, thereby increasing the length of one sample.
[0077]
Subsequently, the system control microcomputer 19 proceeds to step SP9, determines whether or not the end of recording has been instructed by the operation of the trigger operator by the user. If a negative result is obtained here, the system control microcomputer 19 proceeds to step SP10 to store the data in the memory 15A. It is determined whether or not the free space M is equal to or less than 1/4 of the capacity of the memory 15A. Here, if a negative result is obtained, the system control microcomputer 19 returns to step SP8. Thereby, the system control microcomputer 19 repeats the processing procedure of step SP8-step SP9-step SP10-step SP8 when the free space M of the memory 15A is in the range of 1/2 to 1/4 of the capacity of the memory 15A. The sample is set to 2 GOP and the imaging result is recorded on the optical disc 2. If a positive result is obtained in step SP9 by the operation of the trigger switch by the user in the middle, the process proceeds from step SP9 to step SP6, and after the recording of the media data box is completed, a movie box is generated and recorded on the optical disk 2. When the recording of the movie box is completed, the process moves to step SP7, and this processing procedure ends.
[0078]
Thus, in the video disk device 1, one sample is set to one GOP, and after recording on the optical disk 2 is started, the recording time becomes longer than a certain time, and when the capacity of the memory 15A becomes small, one sample becomes two GOPs. The imaging result is set and recorded, and the deterioration of usability in editing processing or the like due to an increase in the length of one sample is avoided as much as possible.
[0079]
On the other hand, in this way, one sample is set to 2 GOPs and the media data box is recorded, and when the free space M of the memory 15A becomes 1/4 or less of the capacity of the memory 15A as the recording progresses, step SP10 Is obtained, the system control microcomputer 19 proceeds from step SP10 to step SP11. Here, the system control microcomputer 19 instructs the file generator 15 to set one sample to 3 GOPs, thereby further increasing the length of one sample.
[0080]
Subsequently, the system control microcomputer 19 proceeds to step SP12, determines whether or not the user has instructed the end of the recording. If a negative result is obtained here, the system control microcomputer 19 proceeds to step SP13, where the free space M of the memory 15A is stored in this memory. It is determined whether or not the capacity of 15A is 1/8 or less. If a negative result is obtained here, the system control microcomputer 19 returns to step SP11. Thereby, the system control microcomputer 19 repeats the processing procedure of step SP11-step SP12-step SP13-step SP11 when the free space M of the memory 15A is in the range of 1/4 to 1/8 of the memory 15A. The sample is set to 3 GOP and the imaging result is recorded on the optical disc 2. If a positive result is obtained in step SP12 by the operation of the trigger switch by the user, the process proceeds from step SP12 to step SP6.
[0081]
Thus, in the video disk device 1, one sample is set to one GOP, and after recording on the optical disk 2 is started, the recording time becomes longer than a certain time, and when the capacity of the memory 15A becomes small, one sample becomes two GOPs. The imaging result is set and recorded, and when the recording further proceeds and the remaining capacity of the memory 15A further decreases, the imaging result is recorded by setting one sample to 3 GOP, and the length of one sample becomes longer. Thus, the deterioration of usability in editing processing or the like due to the above is avoided as much as possible.
[0082]
On the other hand, if one sample is set to 3 GOPs in this way and the free space M of the memory 15A becomes 1/8 or less of the capacity of the memory 15A due to the progress of recording, a positive result is obtained in step SP13. Accordingly, the system control microcomputer 19 proceeds from step SP13 to step SP14. Here, the system control microcomputer 19 instructs the file generator 15 to set one sample to 4 GOPs, thereby further increasing the length of one sample.
[0083]
Subsequently, the system control microcomputer 19 proceeds to step SP15, determines whether or not the user has instructed the end of the recording. If a negative result is obtained here, the system control microcomputer 19 proceeds to step SP16, and the free space M of the memory 15A is stored in the memory 15A. It is determined whether or not the capacity of 15A is 1/16 or less. Here, if a negative result is obtained, the system control microcomputer 19 returns to step SP14. Thus, when the free space M of the memory 15A is in the range of ８ to 1/16 of the capacity of the memory 15A, the system control microcomputer 19 sets one sample to 4 GOP and records the imaging result on the optical disc 2. If a positive result is obtained in step SP15 by the operation of the trigger switch by the user, the process proceeds from step SP15 to step SP6.
[0084]
Thus, in the video disk device 1, one sample is set to 3 GOPs, and when the recording further proceeds and the free space in the memory 15A becomes small, one sample is set to 4 GOPs and the imaging result is recorded. I have.
[0085]
If one sample is set to 4 GOPs in this way and the free space M of the memory 15A becomes equal to or less than 1/16 of the capacity of the memory 15A due to the progress of recording, a positive result is obtained in step SP16. The control microcomputer 19 proceeds from step SP16 to step SP17, and instructs the file generator 15 to set one sample to 5 GOPs.
[0086]
Subsequently, the system control microcomputer 19 proceeds to step SP18, and determines whether or not the user has instructed the end of the recording. If a negative result is obtained here, the system control microcomputer 19 proceeds to step SP19, where the free space M of the memory 15A is stored in this memory. It is determined whether or not the capacity of 15A is 1/32 or less. Here, if a negative result is obtained, the system control microcomputer 19 returns to step SP17. Thus, when the free space M of the memory 15A is in the range of 1/16 to 1/32 of the capacity of the memory 15A, the system control microcomputer 19 sets one sample to 5 GOP and records the imaging result on the optical disc 2. On the way, if a positive result is obtained in step SP18 due to the operation of the trigger by the user, the process proceeds from step SP18 to step SP6.
[0087]
Thus, in the video disk device 1, one sample is set to 4 GOP, and when the recording further proceeds and the free space of the memory 15A becomes small, one sample is set to 5 GOP and the imaging result is recorded. I have.
[0088]
When one sample is set to 5 GOPs in this way, and the free space M of the memory 15A becomes 1/32 or less of the capacity of the memory 15A due to the progress of recording, a positive result is obtained in step SP19. The control microcomputer 19 proceeds from step SP19 to step SP20, and instructs the file generator 15 to set one sample to 6 GOPs.
[0089]
Subsequently, the system control microcomputer 19 proceeds to step SP21, determines whether or not the end of recording has been instructed by the user. If a negative result is obtained here, the system control microcomputer 19 proceeds to step SP22, where the free space M of the memory 15A is stored in this memory. It is determined whether or not the capacity of the 15A becomes 1 [KB] or less. Here, if a negative result is obtained, the system control microcomputer 19 returns to step SP22. Thus, when the free space M of the memory 15A is in the range of 1/32 to 1 [KByte] of the capacity of the memory 15A, the system control microcomputer 19 sets one sample to 6 GOPs and records the imaging result on the optical disc 2. If a positive result is obtained in step SP21 by operating the trigger switch by the user, the process proceeds from step SP21 to step SP6. On the other hand, when the free space of the memory 15A becomes 1 [KByte] or less, a positive result is obtained in step SP22, so that the process proceeds from step SP22 to step SP6, and the recording of the imaging result is forcibly terminated.
[0090]
Thus, the system control microcomputer 19 monitors the progress of the recording based on the free space of the memory 15A, and sequentially increases the length of one sample according to the progress of the recording, thereby effectively avoiding the overflow of the memory 15A. By avoiding this overflow, a QT file is recorded for a long time. The reason why the recording is forcibly ended when the free space of the memory 15A finally becomes 1 [KByte] or less is to allow a margin for the processing of the movie box.
[0091]
FIG. 19 is a characteristic curve diagram showing the relationship between the sample setting in the system control microcomputer 19 and the recording time. As a result, in the video disk device 1, in the memory 15A holding the management information, when the memory capacity decreases due to the progress of recording, the management information increase speed is reduced accordingly, and the speed at which the free space decreases is reduced. Thus, overflow of the management information in the memory 15A can be prevented. Thus, even when a small capacity memory is used, a file or the like in the QT format can be recorded for a long time. In the management information box created in this way, the management unit is initially set to a sufficient length, and the management unit becomes longer due to a decrease in the memory capacity. Can maintain the management unit as originally set. In addition, as the recording time becomes longer, the length of the management unit sequentially becomes longer at the end. As a result, it is possible to avoid as much as possible the deterioration of usability in editing work or the like due to an increase in the length of the management unit.
[0092]
It should be noted that, in such a criterion for determining the free space of the memory 15A, as shown in FIG. 20, in comparison with FIG. Various settings can be made accordingly. Incidentally, the example of FIG. 20 is a case where the determination criteria of the free space M of the memory 15A are set to 3/4, 7/8, 15/16, 31/32, and 63/64, respectively.
[0093]
If the length of one sample is increased stepwise in this way, the length of one chunk becomes relatively long unless the number of samples of one chunk is changed. Accordingly, when video data and audio data are interleaved and multiplexed based on the number of chunks, the interleave cycle is lengthened by an increase in the length of one sample, making continuous reproduction of video data and audio data difficult. Could be.
[0094]
Thus, even if the length of one sample is increased, the number of samples forming one chunk is corrected together within a predetermined range so that the length of one chunk does not change beyond a certain value, and audio data and video data are corrected. Continuous playback may be ensured.
[0095]
(1-2) Operation of First Embodiment
In the above configuration, in the video disk device 1, the video signal DV1 obtained by the imaging means is data-compressed by the video encoder 11 and input to the file generator 15 at a variable rate. The signal DA1 is data-compressed by the audio encoder 12 and input to the file generator 15, where it is converted into a QT file and recorded on the optical disk 2 by a series of subsequent configurations.
[0096]
In the processing in the file generator 15, the video data and the audio data are set as a sample which is a minimum management unit, collected into a chunk by a set of the samples, interleaved for each chunk, and output as data of a media data box. Is recorded on the optical disc 2. While the video data and the audio data are sequentially processed in this manner, information necessary for reproducing each sample and each chunk is acquired and stored in the memory 15A as management information, and the recording of the media data box as the actual data is performed. Upon completion, the data of the movie box according to the management information recorded in the memory 15A is output to the recording means, and the movie box corresponding to the media data box is recorded on the optical disc 2. The video data and the audio data are thereby recorded on the optical disc 2 as QT files.
[0097]
In the QT file recorded in this manner, the management information in the management unit sequentially set in the real data is boxed in a hierarchical structure together with other management information of the real data to form a movie box. Thus, information necessary for reproduction is grasped. That is, with respect to the recording position of the management information unit, the head position is detected by each entry provided in the chunk offset box. Further, each sample is detected by sequentially tracing the top of the file and the top of the chunk based on the recording of the chunk offset box and the data amount of each sample provided in the sample size box.
[0098]
As a result, in the QT file, entries in the chunk offset box and sample size box are provided for each chunk and each sample, and the data amount of these chunk offset boxes and sample size boxes gradually increases as recording progresses. Otherwise, recording in the memory 15A in the file generator 15 will be broken. Similarly, in the composition time-to-sample, the data amount increases as the recording progresses.
[0099]
For this reason, in this embodiment, the length of the sample is gradually increased step by step as the recording progresses under the control of the file generator 15 by the system control microcomputer 19. As a result, in the video disk device 1, the setting speed of chunks and samples can be reduced by the length of one sample, and the data volume increasing speed of the chunk offset box and sample size box is reduced. Can be. As a result, in the video disk device 1, in the memory 15A holding the management information, when the memory capacity decreases due to the progress of the recording, the management information increase speed is reduced accordingly, and the speed at which the free space decreases is reduced. Thus, the failure in the memory 15A can be prevented, and the movie data can be reliably recorded after the recording of the media data is completed. Thus, even when a small capacity memory is used, a file in the QT format can be recorded for a long time.
[0100]
In the movie box created in this way, the sample that is the management unit is initially set to a sufficient length, and the management unit becomes longer due to a decrease in the memory capacity. For, the management unit can be kept as originally set. In addition, as the recording time becomes longer, the length of the management unit sequentially becomes longer at the end. As a result, it is possible to avoid as much as possible the deterioration of usability in editing work or the like due to an increase in the length of the management unit.
[0101]
When the sample length is changed in this way, in the sample description box (sample description), the time sample box (time-to-sample), and the sample chunk box (sample-to-chunk) of the sample table box, On the contrary, the data amount increases. However, the increase in the amount of data in these boxes is increased by registering one entry when the sample length is changed, and is significantly higher than the decrease in the amount of data in the chunk offset box and the sample size box. Small and can be ignored.
[0102]
In this embodiment, however, the progress of the recording is monitored in this manner, and the length of the sample is increased stepwise to prevent a failure in the memory 15A. This is executed by monitoring the free space of a certain memory 15A. As a result, the video disk device 1 can easily and surely record files and the like in the QT format for a long time even when using a small-capacity memory, while avoiding deterioration in usability in editing work and the like as much as possible.
[0103]
Also, while the video data stream of the actual data recorded in this way is an elementary stream related to data compression in GOP units, the sample length gradually increases in GOP units of this elementary stream. When the QT file is reproduced at any position where the length of the sample is switched, the QT file can be reproduced in units of one sample by recording the sample table box. ing.
[0104]
(1-3) Effects of the first embodiment
According to the above configuration, the length of the management unit corresponding to the sample of the QT file is sequentially increased step by step as the actual data is recorded, so that the deterioration of the usability in the editing operation or the like is avoided as much as possible, and the number is reduced. Even when a memory having a large capacity is used, a file in the QT format can be recorded for a long time.
[0105]
In addition, by monitoring the free space of the memory holding the management information and monitoring the progress of the recording of the actual data, it is possible to easily and reliably use a small-capacity memory while minimizing deterioration in usability in editing work and the like. Even in this case, a file or the like in the QT format can be recorded for a long time.
[0106]
Further, when processing video data related to the encoding process in GOP units, the length of the management unit is gradually increased stepwise in GOP units of the video data so that any part is reproduced. However, the recording of the sample table box allows the QT file to be reproduced in units of one sample, and a reduction in random accessibility in the QT file can be effectively avoided.
[0107]
(2) Second embodiment
In this embodiment, JPEG, Motion JPEG, Motion JPEG2000, or the like, which is a compression encoding method that completes data compression processing in units of one frame, is applied to data compression processing of video data. Corresponding to this, as shown in parentheses at the places where the number of GOPs is described in FIGS. In this embodiment, the configuration is the same as that of the first embodiment except that the configuration related to these processes is different.
[0108]
Even in a case where video data is compressed by a compression coding method in which data compression processing is completed in units of one frame as in this embodiment, the same effect as in the first embodiment can be obtained.
[0109]
In this case, the sample length can be sequentially increased step by step in units of frames, so that a decrease in random accessibility in the QT file can be effectively avoided.
[0110]
(3) Third embodiment
In this embodiment, as shown by the broken line in FIG. 2, the remaining battery level is detected by the remaining battery level detection circuit 40, and the characteristic of switching the sample length is changed based on the detection result. In this embodiment, the configuration is the same as that of the first or second embodiment except that the configuration of the system control microcomputer 19 relating to the detection result of the remaining battery level is different.
[0111]
In other words, when the free space of the memory 15A is sufficient, and even when the optical disk 2 has a sufficient free space, the recording time is limited by the remaining amount of the battery when the remaining amount of the battery is small. Eventually, the recording of the QT file must be completed. In this case, as shown by a broken line in FIG. 19, when the recordable time T limited by the battery is short, the recording of the QT file is completed even if one sample is set to 1 GOP by the initial setting. You can do it.
[0112]
Although the memory 15A breaks down when one sample is set to 1 GOP according to the initial setting, recording of the QT file may be completed while the length of one sample is switched to 2 GOP.
[0113]
Thus, in this embodiment, the criterion for judging the free space of the memory 15A is switched according to the recordable time based on the remaining amount of the battery, and the characteristic of increasing the length of one sample is changed according to the remaining amount of the battery. Change adaptively. Further, in the system control microcomputer 19, the recording of the imaging result is forcibly terminated immediately before the battery is exhausted from the result of detection of the remaining battery level.
[0114]
As in this embodiment, if the determination criteria for determining the free space in the memory is switched according to the recordable time based on the remaining amount of the battery, the characteristic of increasing the length of one sample is adaptively changed. Usability is improved as compared with the first and second embodiments, and the same effect as in the first and second embodiments can be obtained.
[0115]
(4) Fourth embodiment
In this embodiment, the characteristic of switching the length of the sample according to the free space of the recording medium is changed. In this embodiment, the configuration is the same as that of the first, second or third embodiment except that the configuration of the system control microcomputer 19 relating to the processing of the free space is different.
[0116]
That is, when the free space of the memory 15A is sufficient, even when the battery is sufficient, when the free space of the optical disk 2 is small, the recording time is limited by the free space of the optical disk 2, and after all, the recording of the QT file is completed. Have to do it.
[0117]
In this case as well, the recording of the QT file is completed even if one sample is set to 1 GOP by the initial setting, as in the case where the recordable time is limited by the remaining amount of the battery described in the third embodiment. If this is possible, the recording of the QT file may be completed while the length of one sample is switched to 2 GOPs, although the memory 15A will fail if one sample is set to 1 GOP.
[0118]
Thus, in this embodiment, the criterion for judging the free space of the memory 15A is switched according to the free space of the optical disk 2 as the recording medium, and the characteristic of increasing the length of one sample is changed to the free space of the recording medium. It changes adaptively according to it. Further, the system control microcomputer 19 monitors the free space of the optical disc 2 and the data amount of the management information recorded in the memory 15A. Exit and record the movie box.
[0119]
If the characteristic of increasing the length of one sample is adaptively changed according to the free space of the recording medium as in this embodiment, the usability is improved as compared with the first to third embodiments. Thus, effects similar to those of the first and second embodiments can be obtained.
[0120]
(4) Other embodiments
In the above-described embodiment, the case where the sample of the audio data is changed in accordance with the change of the sample in the video data has been described. However, the present invention is not limited to this. May correspond to a change in the sample in the video data.
[0121]
Further, in the above-described embodiment, the case where the progress of recording is monitored based on the free space of the memory has been described. Monitoring method can be widely applied.
[0122]
In the above-described embodiment, audio data encoded by the compression encoding method of MPEG1 Audio Layer 2 and video data encoded by the compression encoding method of MPEG2 Video, Motion JPEG, and Motion JPEG2000 are recorded on the optical disc 2. Although the case has been described, the present invention is not limited to this, and can be widely applied to recording of audio data and video data applicable to a QT file.
[0123]
Further, in the above-described embodiment, a case has been described in which the present invention is applied to a video disk device and a QT file is recorded. However, the present invention is not limited to this, and the ISO Base Media file format (MPEG4-part12), Motion JPEG2000 Like the QT file, such as the (MJ2) file format and the AVC (Advanced Video Coding: MPEG4-part10) file format, the management information in the management unit is combined with other management information to record a file that is boxed in a hierarchical structure. Can be widely applied.
[0124]
Further, in the above-described embodiment, the case where the present invention is applied to a video disk device and a file is recorded on an optical disk has been described. It can also be widely applied to recording in
[0125]
Also, in the above-described embodiment, the case where the present invention is applied to a video disk device has been described. However, the present invention is not limited to this, and a mobile phone having an imaging function, a PDA (Personal Digital Assistants), In short, the present invention can be widely applied to various recording devices that record video data, such as a server that records imaging results obtained wirelessly.
[0126]
【The invention's effect】
As described above, according to the present invention, the length of the management unit corresponding to the sample of the QT file is gradually increased step by step as the recording of the actual data progresses, so that the deterioration of the usability in the editing work or the like is avoided as much as possible. Thus, even when a small capacity memory is used, a file or the like in the QT format can be recorded for a long time.
[Brief description of the drawings]
FIG. 1 is a flowchart showing a processing procedure of a system control microcomputer in a video disk device according to a first embodiment of the present invention.
FIG. 2 is a block diagram showing a video disk device according to the first embodiment of the present invention.
FIG. 3 is a schematic diagram illustrating a QT file.
FIG. 4 is a schematic diagram illustrating a box structure of a QT file.
FIG. 5 is a table showing a box structure of a QT file.
FIG. 6 is a table showing a continuation of FIG. 5;
FIG. 7 is a table showing a sample description box.
FIG. 8 is a chart showing a time sample box.
FIG. 9 is a chart showing a sample size box.
FIG. 10 is a chart showing a sample chunk box.
FIG. 11 is a time chart showing a relationship between video data and a QT file.
FIG. 12 is a time chart showing a relationship between audio data and a QT file.
FIG. 13 is a time chart showing a relationship between video data and a QT file when one sample is set to 4 GOPs.
FIG. 14 is a time chart showing a relationship between audio data and a QT file in relation to a chunk offset.
FIG. 15 is a schematic diagram illustrating a layout of a QT file on an optical disc.
FIG. 16 is a schematic diagram illustrating a layout of a QT file on an optical disc in a case where chunks of video data and audio data are arranged in pairs.
FIG. 17 is a schematic diagram illustrating another example of FIG. 16;
FIG. 18 is a flowchart showing a continuation of FIG. 1;
FIG. 19 is a characteristic curve diagram showing sample switching according to the processing procedures of FIGS. 1 and 18.
FIG. 20 is a characteristic curve diagram showing another example of FIG. 19;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Video disk apparatus, 2 ... Optical disk, 11 ... Video encoder, 12 ... Audio encoder, 15 ... File generator, 15A, 17, 20 ... Memory, 19 ... System control microcomputer, 40 …… Battery level detection circuit

Claims (6)

In a file recording device that records sequentially input real data on a recording medium using a file of a predetermined format,
The file is
Management information for managing the actual data is put together to form a management information box,
The management information box includes:
The management information based on the management unit sequentially set in the real data is formed as a box with a hierarchical structure together with other management information of the real data,
The file recording device,
Recording means for recording the data of the box of the actual data and the management information on the recording medium,
The management unit is sequentially set in the real data, the management information is sequentially acquired in correspondence with the recording of the real data, and the acquired management information is stored in a memory. Data processing means for outputting the data of the box of the management information to the recording means,
Monitoring means for monitoring the progress of the recording of the actual data,
Control means for controlling the data processing means based on the monitoring result of the monitoring means to sequentially increase the length of the management unit in a stepwise manner as the actual data is recorded; apparatus. The monitoring means,
2. The file recording device according to claim 1, wherein the progress of the recording of the actual data is monitored by monitoring the free space of the memory. The actual data is
Video data compressed in GOP units.
The control means,
2. The file recording apparatus according to claim 1, wherein the length of the management unit is sequentially increased stepwise in units of a GOP of the video data. The actual data is
Video data compressed by a method in which data compression processing is completed in units of one frame.
The control means,
2. The file recording apparatus according to claim 1, wherein the length of the management unit is sequentially increased step by step in units of frames of the video data. The actual data is
Variable rate data,
The management information according to the management unit includes:
2. The file recording apparatus according to claim 1, wherein the data amount is the data amount of the actual data in the management unit for each of the management units. After recording the sequentially input real data on a recording medium, the management information in the management unit sequentially set in the real data, the management information box in which the other management information of the real data are collectively boxed into a hierarchical structure, In a file recording method for recording on a recording medium,
A file recording method, wherein the length of the management unit is sequentially increased stepwise as the recording of the actual data progresses.

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