JP4321427B2 - Recording / reproducing apparatus and editing method - Google Patents

Description

  The present invention relates to a recording / reproducing apparatus and an editing method for editing AV (Audio / Video) data and real-time metadata corresponding to AV data using a randomly accessible recording medium.

  Particularly in a professional field such as a broadcasting station, digital audio data and / or digital video data shot by a video camera and recorded on a recording medium are used after being edited as necessary. In addition to the digital audio data and / or digital video data, real-time metadata that is information about the digital audio data and / or digital video data is recorded and used for editing. Hereinafter, these digital audio data, digital video data, and real-time metadata are collectively referred to as AV (Audio / Video) data. In the editing operation, generally, a desired video cut is extracted from AV data reproduced from a recording medium, and the start point (IN point) and end point (OUT point) of the video cut are marked. Then, a plurality of video cuts are connected based on each marked IN point and OUT point to obtain a video in which desired video cuts are continuously connected.

Conventionally, a serial access type recording medium such as a magnetic tape has been used for recording and reproducing AV data. In addition to this, in recent years, a randomly accessible recording medium such as an optical disk, a hard disk, or a semiconductor memory has been frequently used for recording and reproducing AV data. Randomly accessible recording media can be non-linearly edited so that the editing operation can be completed on the same recording medium. Hereinafter, this randomly accessible recording medium is referred to as a non-linear recording medium. Patent Document 1 describes an editing apparatus that performs such nonlinear editing.
JP 2001-319463 A

  A non-linear recording medium generally has a very high access speed compared to a serial access type recording medium such as a magnetic tape. In particular, a hard disk has a high access speed and a large recording capacity, and can record a large amount of AV data. In recent years, optical discs and semiconductor memories having a sufficient storage capacity for recording a plurality of AV data have appeared. In such a non-linear recording medium, reproduction of AV data between the IN point and OUT point used for editing and recording of the edited AV data are performed in parallel on one recording medium, and after editing. The AV data can be easily recorded at other positions on the recording medium. For this reason, when a non-linear recording medium is used, non-destructive editing is performed in which editing is performed with the original AV data remaining.

  Conventionally, editing using a non-linear recording medium has been performed by one of the following two methods. A first editing method using a conventional non-linear recording medium is a method of writing the entire editing result including an unedited portion in an empty area on the recording medium. The second method is a method of writing only AV data necessary for editing into a free area on the recording medium and generating control data instructing continuous reproduction of the AV data and the non-editing area. Both are nondestructive edits in which no changes are made to the original data being edited.

  On the other hand, AV data is generally compressed and encoded by a predetermined method and recorded on a non-linear recording medium for each block of a predetermined size. During reproduction, the recording medium is accessed in units of blocks, and the AV data recorded in the block is read out in a time shorter than the reproduction time when real time reproduction is performed, and stored in the memory. The data stored in the memory is decoded and output in real time.

  By the way, normally, with the recording of AV data on a recording medium, header information and footer information are recorded on the AV data to be recorded. The header information and footer information are rewritten according to the editing content at the time of editing.

  Also, in general, in an editing operation, a pre-roll operation that plays back from an appropriate position of a clip to an IN point before starting editing, and an appropriate operation from the OUT point after the editing is completed, continuously with the editing process between the IN point and the OUT point. A post-roll operation is performed to continue the reproduction to a correct position.

  Conventionally, header information and footer information updated by editing are recorded on a recording medium immediately after the editing ends. That is, immediately after editing, the above-described post-roll playback operation and the operation of recording the header information and footer information of the clip to be edited with the IN point and OUT point set are performed in parallel. Become. More specifically, while the block read and stored in the memory by the post-roll operation is being played back, the seek operation is performed up to the position where the header information and the footer information are recorded, and the header information and the footer information are recorded. Is done. When this recording is completed, the seek operation is performed up to the position where the data to be reproduced is recorded by the post-roll operation.

  In such an operation, when the position for recording the header information and footer information on the recording medium is separated from the reproduction position by the post-roll operation, the time required for seeking when recording the header information and the footer information becomes long. . On the other hand, recording of header information and footer information and reproduction by post-roll operation during seek operation at that time are performed based on data read from the memory. Therefore, during the recording and seeking operation of header information and footer information, all the data stored in the memory is read out by the reproduction by the post-roll operation, and there is no data to be reproduced until the next reading operation is started. There is a problem in that the playback may be interrupted due to an underflow state and post-roll operation.

  Such a problem becomes more conspicuous when an optical disc having a slower seek speed, read speed, and write speed than a hard disk is used as a recording medium. Even when a hard disk is used as a recording medium, there is a problem when AV data with a higher bit rate is handled or when a plurality of AV data are handled in parallel.

  Accordingly, it is an object of the present invention to provide a recording / reproducing apparatus and an editing method in which reproduction by post-roll operation after editing operation is not interrupted.

This invention, in order to solve the problems described above, performs video data using a randomly accessible recording medium, audio data, or the recording and playback of the real-time meta data corresponding to the video data or audio data, the A recording / playback apparatus that performs destructive editing on video data, audio data, or real-time metadata corresponding to the video data or audio data recorded on the recording medium Access control means for controlling time-division writing to an accessible recording medium and reading from the recording medium, and buffer means for temporarily storing data read from the recording medium. Recorded video data, audio data, or the video data When the reproduction operation is continuously performed after the editing operation on the real-time metadata corresponding to the audio data, writing of the header and / or footer updated based on the editing to the recording medium is performed immediately after the editing operation and the reproduction operation. The recording / reproducing apparatus is configured to determine which to perform after completion based on the amount of data that can be read from the buffer means until the writing of the header and / or footer to the recording medium is completed.

  In addition, the present invention records and reproduces video data, audio data, or real-time metadata corresponding to video data or audio data using a randomly accessible recording medium, and is recorded on the recording medium on the recording medium. An editing method for performing destructive editing on recorded video data, audio data, or real-time metadata corresponding to video data or audio data, and writing to and reading from a randomly accessible recording medium Video data, audio data recorded on the recording medium, or a step of temporarily storing the data read from the recording medium in the buffer means, For video data or audio data When the reproduction operation is continuously performed after the editing operation for the corresponding real-time metadata, writing of the header and / or footer updated based on the editing to the recording medium is performed immediately after the editing operation or after the completion of the reproduction operation. This is an editing method in which it is determined based on the amount of data that can be read from the buffer means until the writing of the header and / or footer to the recording medium is completed.

  As described above, according to the present invention, a playback operation is continuously performed after an editing operation on video data, audio data, or real-time metadata corresponding to video data or audio data recorded on a randomly accessible recording medium. In this case, since the header and / or footer updated based on the editing is written to the recording medium after the reproduction operation is completed, the seek operation for the header and / or footer writing process is the editing operation. It is not performed during the subsequent playback operation, and the playback operation after the editing operation is not interrupted.

  Further, the present invention is configured to control time-division writing to and reading from a randomly accessible recording medium, and video data, audio data, or video data recorded on the recording medium or When the playback operation is continuously performed after the editing operation on the real-time metadata corresponding to the audio data, the header and / or footer updated based on the editing is written to the recording medium immediately after the editing operation and after the completion of the playback operation. Is determined based on the amount of data that can be read from the buffer means for temporarily storing data read from the recording medium until the writing of the header and / or footer to the recording medium is completed. For header and / or footer write processing Buffer means there is no cause a buffer underflow by the operation, there is no interruption playback operation after editing operations.

  The present invention is based on editing after a post-roll operation after an editing operation for video data, audio data, or real-time metadata corresponding to video data or audio data recorded on a randomly accessible recording medium is completed. Since the updated header and / or footer are written to the recording medium, the seek operation for writing the header and / or footer is not performed during the post-roll operation, and reproduction by the post-roll operation is not performed. There is an effect that there is no interruption.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, in order to facilitate understanding, a recording medium and a recording / reproducing apparatus applicable to the present invention will be described. FIG. 1 shows an example of data arrangement in a disc-shaped recording medium. The data arrangement shown as an example in FIG. 1 is a general data arrangement in a disc-shaped recording medium that can be randomly accessed, such as a recordable optical disk or hard disk. Such a data arrangement can also be applied to a non-disc-shaped recording medium such as a semiconductor memory. The logical address space is an area where arbitrary data can be recorded / reproduced.

  A file system FS is arranged at the leading and trailing ends of the logical address. Arbitrary data is recorded in a predetermined format generally called a file in the logical address space. Data on the recording medium is basically managed in file units. File management information is recorded in the file system FS. A file system layer of a system control unit (described later) of the recording / reproducing apparatus can manage various kinds of data on one recording medium by referring to and operating information of the file system FS.

  A replacement area is arranged outside the logical address space. The spare area is an area that can be used as an alternative when a part of the recording medium cannot be physically read or written due to a defect. For example, when a defective area is recognized at the time of access to the recording medium (particularly at the time of recording), a replacement process is normally performed, and the address of the defective area is moved into the replacement area.

  The usage status of the spare area is stored as a defect list in a predetermined area, and is used by a drive control unit of the recording / reproducing apparatus and a lower hierarchy of the system control unit. In other words, in the lower layers of the drive control unit and system control unit described later, by referring to the defect list when accessing the recording medium, even when replacement processing is performed, access to an appropriate area is performed. It can be carried out. By this mechanism of the spare area, the host application can perform data recording / reproduction with respect to the recording medium without considering the presence / absence or position of the defective recording area on the recording medium.

  In the case of a disc-shaped recording medium, the replacement area is often arranged on the innermost or outermost side of the disc. When the disk rotation control is performed by zone control in which the rotation speed is changed stepwise in the radial direction of the disk, a replacement area may be provided for each zone. When the recording medium is not a disk-shaped recording medium such as a semiconductor memory, it is often arranged on the side having the smallest physical address or the largest physical address.

  In an application that handles AV data, a group of data that is a unit that requires continuous synchronized playback, that is, playback that guarantees real-time playback is called a clip. For example, a group of data from the start to the end of shooting by the video camera is used as a clip. The entity of a clip consists of a single file or multiple files. In the present invention, a clip consists of a plurality of files. Details of the clip will be described later.

  For example, an NRT (Non Real Time) area in which an arbitrary file other than a clip can be recorded is arranged at the head side in the logical address space, and clips are sequentially packed from the next of the NRT area. The clip is arranged avoiding the defect position on the optical disc 100 so that the replacement process described above is not performed. A header (H) and a footer (F) are added to each clip. In this example, the header and footer are arranged together on the rear end side of the clip.

  In the logical address space, an area where no data is recorded or an area where data has been recorded in the past but is no longer needed is managed as an unused area in the file system FS. A recording area is allocated to a file newly recorded on the recording medium based on an unused area. The management information of the file is added to the file system FS.

  When a recordable optical disc is used as the recording medium, the present invention records the clip on the recording medium with an annual ring structure. The annual ring structure will be described with reference to FIGS. 2 and 3. FIG. 2A is an example showing one clip 20 on the timeline. In this example, the clip 20 includes seven files of video data 21, audio data 22 </ b> A to 22 </ b> D, auxiliary AV data 23, and real-time metadata 24.

  The video data 21 is video data obtained by compression-coding baseband video data at a high bit rate. As the compression encoding method, for example, MPEG2 (Moving Pictures Experts Group 2) method is used. As the audio data 22A, 22B, 22C and 22D, baseband audio data is used, each of which is 2-channel audio data. However, the audio data 22A, 22B, 22C, and 22D may be audio data obtained by compression-coding baseband audio data at a high bit rate. The video data 21 and the audio data 22A to 22D are data to be actually broadcast and edited, and are referred to as main line data.

  The auxiliary AV data 23 is data obtained by compressing and multiplexing baseband video data and audio data at a lower bit rate than main line video data and audio data. As the compression encoding method, for example, the MPEG4 method is used, and main line AV data is generated by compression encoding so as to reduce the bit rate to, for example, several Mbps (Mega bits per second). The auxiliary AV data 23 is data used as a proxy for main line data when determining edit points and the like, and is also referred to as proxy data. In this embodiment, the number of audio data channels in the auxiliary AV data is fixed to 8 channels.

  Metadata is high-order data related to certain data, and functions as an index for representing the contents of various data. The metadata includes real-time metadata 24 generated along the time series of the main AV data and non-time series meta data generated for a predetermined section such as for each scene in the main AV data. There are two types of data. The non-time series metadata is recorded in, for example, the NRT area described with reference to FIG.

  As shown in FIG. 2B, the clip 20 is divided on the basis of a predetermined reproduction time and recorded on the optical disc as an annual ring structure. As an example is shown in FIG. 2C, one annual ring includes video data 21, audio data 22A to 22D, auxiliary AV data 23, and real-time metadata 24 for one round of a track so that each playback time zone corresponds. The data is divided into predetermined reproduction time units having the above data size, and the divided reproduction time units are sequentially arranged and recorded. That is, each data constituting the clip 20 is interleaved in a predetermined time unit by the annual ring structure and recorded on the optical disc.

  The data forming the annual ring is referred to as annual ring data. The annual ring data has an amount of data that is an integral multiple of the smallest recording unit on the disc. The annual rings are recorded so that the boundaries coincide with the block boundaries of the recording units of the disc.

  FIG. 3 shows an example of annual ring data formed on the optical disc 100. In the example of FIG. 3, auxiliary AV annual ring data # 1, real-time meta annual ring data # 1, audio annual ring data # 1 for the number of channels, and video annual ring data # 1 are recorded in order from the inner circumference side of the optical disc 100. In this cycle, annual ring data is handled. On the outer peripheral side of the video annual ring data # 1, a part of the annual ring data of the next cycle is further shown as auxiliary AV annual ring data # 2.

  In the example of FIG. 3, the playback time zone for the 1-year ring data of the real-time meta annual ring data corresponds to the playback time zone for the 1-year ring data of the auxiliary AV annual ring data. It shows that the playback time zone corresponding to two periods of the time zone and the audio annual ring data corresponds. Similarly, it is shown that the playback time zone for one annual ring data of real-time meta annual ring data corresponds to the playback time zone for four cycles of video annual ring data. Such association between the reproduction time zone and the cycle of each annual ring data is set based on, for example, each data rate. In the following, it is assumed that the playback time for one ring data is 2 seconds.

  Note that the header and footer for the clip are also recorded by the annual ring structure as shown in FIG. 2D.

  FIG. 4 schematically shows a configuration of an example of a recording / reproducing apparatus applicable to the present invention. This recording / playback apparatus is connected to, for example, a video camera, and performs signal processing on AV data obtained by the video camera and records it on the optical disc 100. Also, AV data and the like recorded on the optical disc 100 are reproduced, subjected to predetermined signal processing and output. Furthermore, editing work can be performed on AV data recorded on the optical disc 100 based on an instruction from a control panel attached to the apparatus or an input apparatus connected via an RS-422 interface (not shown).

  The system control unit 17 includes one or a plurality of CPUs (Central Processing Units), a ROM (Read Only Memory) in which programs and data are stored in advance, a RAM (Random Access Memory) used as a work memory of the CPU, and the like. According to the program read from the ROM, the entire recording / reproducing apparatus is controlled in accordance with the control signal input from the control input / output terminal. For example, an input device is connected to the control input terminal via the control panel described above or an RS-422 interface.

  The configuration of the recording system will be described. A recording operation is instructed to the system control unit 17 from the control input / output terminal. Based on the recording operation instruction, the system control unit 17 issues an instruction to each unit of the recording / reproducing apparatus so that the recording operation can be started.

  For example, baseband AV data to be recorded is supplied to the recording signal processing unit 13 from a video camera or an external device. The recording signal processing unit 13 performs predetermined signal processing and compression encoding processing on the input baseband AV data, and generates main AV data and auxiliary AV data for recording.

  For example, baseband video data is made up of one frame of 1 GOP (Group Of Picture) according to the MPEG2 system, and further compressed and encoded so as to have a predetermined bit rate. Data is generated. As for audio data, for example, PCM (Pulse Code Modulation) data is used as main line audio data without being compressed and encoded.

  In addition, baseband video data and audio data are compression-encoded by, for example, the MPEG4 system with a fixed bit rate of several Mbps, and auxiliary AV data is generated. As for video data, auxiliary AV data is encoded in units of a predetermined number of frames. In this embodiment, the video data of the auxiliary AV data is composed of 10 frames of one I picture and nine P pictures, and 1 GOV (Group Of Video Object Plane) is formed.

  Audio data in the auxiliary AV data is generated by instantaneously compressing main-line audio data by combining, for example, sampling frequency conversion for compressing the time axis direction and logarithmic compression for compressing the word length. For example, the sampling frequency conversion is performed by down-sampling main-line audio data with a sampling frequency of 48 kHz to audio data with a sampling frequency of 8 kHz. As a word length compression method, an A-law method can be used in which the quantization step is set small when the data has a small amplitude and the word length is compressed by setting the quantization step large when the data has a large amplitude. Further, by performing band limitation on the main line audio data in advance with a low-pass filter before compression encoding, it is possible to minimize deterioration in sound quality due to compression encoding. In this embodiment, a 512 tap FIR (Finite Impulse Response) filter is used as the low pass filter.

  The main line AV data and auxiliary AV data output from the recording signal processing unit 13 are supplied to the formatter / unformatter unit 12. The main line AV data and auxiliary AV data output from the recording signal processing unit 13 and real-time metadata output from the metadata processing unit 15 described later constitute a clip.

  Under the control of the system control unit 17, the metadata processing unit 15 performs real-time metadata recorded on the optical disc 100 together with main AV data and auxiliary AV data, and data (header and footer) for arranging clips into a predetermined format. ) Is generated. The metadata processing unit 15 also generates non-time series metadata. These data generated by the metadata processing unit 15 are supplied to the formatter / unformatter unit 12.

  The formatter / unformatter unit 12 arranges each data supplied from the recording signal processing unit 13 and the metadata processing unit 15 in the above-described annual ring structure. For example, the formatter / unformatter unit 12 has a memory, and stores the supplied data in the memory in an address arrangement corresponding to the annual ring structure. Then, read control is performed so that data is read from the memory in units of annual rings. The clips arranged in the annual ring structure are supplied to the drive control unit 11 in units of annual rings.

  The drive control unit 11 performs predetermined recording signal processing on the supplied data during recording, and also performs read / write unit 10 and servo control based on signals obtained from a read / write unit 10 and a servo unit 14 described later. By controlling the unit 14, the writing operation is controlled so that the recording data is written at a predetermined address of the optical disc 100.

  The main-line AV data, auxiliary AV data, real-time metadata, header, and footer supplied from the formatter / unformatter unit 12 to the drive control unit 11 are error correction encoded in units of ECC (Error Correction Coding) blocks of a predetermined size. The The error-corrected encoded data is recorded and encoded in a predetermined manner, and is supplied as a recording signal to the read / write unit 10.

  The read / write unit 10 includes an optical pickup made of, for example, a laser diode, and a laser driving circuit that controls the laser power of the optical pickup in accordance with the recording / reproducing operation mode. The read / write unit 10 also has a thread drive unit that controls the position of the optical pickup in the radial direction of the disk 100 based on a thread control signal supplied from the servo control unit 14. The servo control unit 14 performs control of the sled driving unit and control of a spindle motor (not shown) for rotationally driving the optical disc 100 based on control signals respectively supplied from the drive control unit 11 and the system control unit 17.

  The read / write unit 10 drives the optical pickup based on the recording signal supplied from the drive control unit 11 and performs recording on the optical disc 100 based on the recording signal. The recording position is based on information indicating the area usage status of the optical disc 100 based on information of the file system FS read from the optical disc 100 in advance prior to the recording operation, and based on an instruction from the control input / output terminal. And specified by the drive control unit 11.

  In this embodiment, the recording operation on the optical disc 100 is continuously performed for each annual ring unit. In this embodiment, the minimum recording unit block size of the optical disc 100 and the ECC block size are the same, and recording is performed so that the minimum recording unit of the optical disc 100 matches the ECC block. In other words, in this embodiment, the ECC block is a unit for recording signal processing, and is also a block that is actually a unit for reading and writing data on the optical disc 100.

  Further, for each annual ring unit, for example, a marker block composed of a predetermined data string for one to several ECC blocks is recorded. This marker block is used to make it possible to reproduce the recorded data up to the previous annual ring when a recording error or the like occurs during recording of the annual ring. Therefore, each time the recording for one annual ring is completed, the marker block for the annual ring becomes unnecessary.

  The configuration of the reproduction system will be described. A reproduction operation is instructed to the system control unit 17 from the control input / output terminal. Based on this playback operation instruction, the system control unit 17 issues an instruction to each unit of the recording / playback apparatus so that the playback operation can be started. The read / write unit 10 is controlled in a predetermined manner, and reading is performed for each recording unit from the designated address of the optical disc 100. The read reproduction signal is supplied from the read / write unit 10 to the drive control unit 11.

  The drive control unit 11 decodes the recording code of the supplied reproduction signal to obtain reproduction data, and further decodes the error correction code of the reproduction data to perform error correction. The error-corrected reproduction data is supplied to the formatter / unformatter unit 12. The formatter / unformatter unit 12 separates the supplied reproduction data for each data type such as main line AV data, auxiliary AV data, and real-time metadata. For example, the supplied reproduction data is stored in a memory included in the formatter / unformatter unit 12. When the annual ring portion is accumulated, each data constituting the annual ring is read and supplied to the corresponding processing unit. The main line AV data and the auxiliary AV data are supplied to the reproduction signal processing unit 16. The real time metadata is supplied to the metadata processing unit 15.

  The metadata processing unit decodes the supplied real-time metadata and supplies the decoded information to the system control unit 17.

  The reproduction signal processing unit 16 performs predetermined signal processing on the supplied main AV data and auxiliary AV data. For example, main line AV data and / or auxiliary AV data are each decoded. It is also possible to output without decoding. As for the auxiliary AV data, the video data is decoded in units of 1 GOV since 1 GOV is formed with 10 frames. In addition, the audio data is instantaneously decompressed by A-Law method word length compression, and the downsampled sampling frequency is upsampled to 48 kHz. During upsampling, a 512-tap FIR filter similar to that used during recording is used as a low-pass filter, and sound quality degradation is minimized.

  The network interface (I / F) 18 is connected to a network such as the Internet or a LAN (Local Area Network), for example, and controls communication via the network. For example, this recording / reproducing apparatus can receive AV data transmitted via a network and record it on the optical disc 100.

  For example, AV data transmitted via the network and received by the network I / F 18 is supplied to the formatter / unformatter unit 12. In this case, the recording signal processing unit 13 may be supplied from the network I / F 18. It is also conceivable to supply the drive control unit 11 directly from the network I / F 18. For example, when AV data is received by the network I / F 18, the system control unit 17 determines the format of the received AV data, performs recording signal processing, processing by the formatter / unformatter unit 12, Perform data processing. The processed AV data is supplied to the drive control unit 11, subjected to predetermined processing, and then recorded on the optical disc 100.

  AV data and auxiliary AV data read from the optical disc 100 can be supplied to the network I / F 18 via the formatter / unformatter unit 12 and transmitted to the network. In this case, since the auxiliary AV data is compressed and encoded at a low bit rate, it is suitable for transmission over a network.

  This recording / reproducing apparatus can perform editing operations on clips on the optical disc 100. For example, the AV data on the optical disc 100 can be edited using AV data supplied from the outside or other AV data recorded on the optical disc 100 itself.

  Next, an editing method applicable to the present invention will be described. In the present invention, editing of a clip recorded on a randomly accessible recording medium such as the optical disc 100 is performed by destructive editing. Destructive editing is a process for overwriting necessary data on the underlying data to be edited. In destructive editing, appropriate data of the background data is overwritten with the editing data and directly rewritten in accordance with the instruction of editing points such as the IN point and OUT point and the specification of the editing mode such as insert editing and assembly editing. At this time, the background data is not moved or copied to another area on the recording medium. In the following, data on the side where an editing point is set as an editing target is referred to as background recording or background data, and data on the side to be written to the editing point is referred to as editing data.

  This will be described more specifically with reference to FIG. The clip # 1 before editing shown in FIG. 5A is set as background data, the IN point and the OUT point are set for the clip # 1, the editing target is designated, and other editing data is provided between the IN point and the OUT point. Consider insert editing that inserts a video cut. In destructive editing, editing data is directly overwritten between the IN point and OUT point of the background data. Therefore, after editing, as shown in FIG. 5B, in clip # 1, the data from the beginning of clip # 1 to the IN point becomes the background data (original clip # 1 data), and between IN point and OUT point Becomes the editing data, and further, the data from the OUT point to the end of the clip # 1 becomes the background data.

  In the destructive editing, the header H # 1 and the footer F # 1 corresponding to the clip # 1 are rewritten as the clip # 1 is edited.

  As described above, in destructive editing, data outside the editing target section in the base recording does not need to be rewritten, so that the time required for editing is minimized. In addition, since the editing data is overwritten on the underlying editing target section, the unused area does not change by editing. Therefore, the editing operation can always be executed regardless of the state of the unused area, such as the size of the unused area and the degree of fragmentation of the unused area, and the editing complexity. In addition, in destructive editing, the data arrangement does not move due to editing. Therefore, if the clip by the base recording (clip # 1 in the example of FIG. 5A) can be continuously played back, the edited result can also be played back continuously. Is guaranteed.

  As described above, according to the present invention, since the destructive editing is performed by overwriting the editing data with respect to the background data using the non-linear recording medium, the recording medium does not need a free area. In addition, since the data to be rewritten is minimized by destructive editing, the time required for rewriting accompanying the editing operation is short. Further, since the editing is performed by overwriting the editing data with respect to the background data by destructive editing, the seek operation does not increase compared to before editing even when the editing result is reproduced. This also enables advanced editing.

  Next, header and footer update processing at the time of destructive editing according to an embodiment of the present invention will be described. In destructive editing, the data arrangement of the base record is basically saved. That is, the header and footer changed based on the editing result are overwritten at the position where the header and footer were recorded as the base record. Therefore, normally, the editing end point in the clip body and the recording positions of the header and footer are at positions separated from each other on the recording medium. The header and footer based on the editing result are not limited to this. Even when the header and footer based on the editing result are recorded at different positions without overwriting the header and footer of the background data, the header and footer are placed near the editing end point on the recording medium. There is not always a recordable free area.

  On the other hand, in an editing operation, a post-roll operation is generally performed in which reproduction is continued even after editing is completed. By confirming the reproduced image by the post-roll operation, the next editing start point can be designated continuously. On the recording medium, if the distance between the editing end point and the header and footer writing position is large, the seek time from the editing end point to the header and footer writing position becomes long, and playback by post-roll operation is performed. In the buffer used in the above, there is a possibility that a buffer underflow may occur and reproduction during the post-roll operation may be broken. In one embodiment of the present invention, the timing of writing the header and footer is controlled to prevent such buffer underflow associated with updating the header and footer after editing, so that reproduction by post-roll operation is not interrupted. To.

  First, the data write-back process associated with the editing operation will be described. The editing operation of destructive editing is often an operation of overwriting and recording editing data while reproducing background data. In this case, it is necessary to execute the reproducing operation and the recording operation in parallel. Here, in a system having only one system of recording and reproducing units, the reproducing operation and the recording operation are repeated by time division, and apparently the recording operation and the reproducing operation are performed in parallel. On the other hand, in a system having two or more recording / reproducing units, when performing the time-sharing operation as described above, a part of a plurality of recording / reproducing systems is used for the recording operation, and another part of the system is used. It is conceivable that recording and reproduction are performed in parallel so as to be applied to the reproduction operation. Hereinafter, a case where the recording operation and the reproducing operation are performed by time division operation will be described with reference to FIG.

  FIG. 6 schematically shows signal processing and buffer trajectories during the destructive editing operation. 6A to 6E show an example of data transition in each part of the recording / reproducing apparatus for each annual ring. FIG. 6F shows an example recording / reproducing operation in the optical disc 100. Blocks with diagonal lines and “W” indicate recording, and blocks with “R” indicate reproduction. FIG. 6G shows a transition of prefetch data stored in the reproduction side buffer for reproduction, and FIG. 6H shows a transition of write-back data stored in the recording side buffer for recording.

  FIG. 6A shows a virtual read timing when it is assumed that data for one annual ring is read from the optical disc 100 with a playback time for one annual ring (hereinafter referred to as “one annual ring time” as necessary). Actually, as shown in an example in FIG. 6F, for example, the data of annual ring # 1 is read from the optical disc 100 at a speed higher than the reproduction time for one annual ring and is stored in the reproduction side buffer. Accumulating data in the reproduction side buffer in this way is called prefetch, and data accumulated in the reproduction side buffer is called prefetch data. The data stored in the reproduction-side buffer is read at a predetermined timing, and is decoded by the reproduction signal processing unit 16 at the annual ring time as shown in FIG. 6B.

  In the editing system, editing data is generated in a predetermined phase relationship in synchronization with the output from the recording / reproducing apparatus, and the generated editing data is input to the recording / reproducing apparatus. FIG. 6C shows an example in which the input / output phases of the recording / reproducing apparatus match. That is, the decoded data as shown in FIG. 6B is output as, for example, an output signal from the recording / reproducing apparatus, and edit data that is synchronized with the output signal and whose phase is matched is input to the recording / reproducing apparatus. However, the phase of the output signal from the recording / reproducing apparatus and the editing data may be shifted.

  The edit data input to the recording / reproducing apparatus is encoded by the recording signal processing unit 13 (FIG. 6D), and then supplied to the read / write unit 10 via the formatter / unformatter unit 12 and the drive control unit 11. Then, it is recorded on the optical disc 100 (FIG. 6E). Data is stored in the recording buffer, and data for one annual ring is recorded on the optical disc 100 at a speed higher than the annual ring time (FIG. 6F). Data stored in the recording buffer in this way is referred to as write back data.

  As described above, the actual recording and reproduction operations with respect to the optical disc 100 by the read / write unit 10 are alternately performed by time division as shown in FIG. 6F. When recording and playback are switched, a seek operation for an annual ring corresponding to a delay occurring in the recording / playback apparatus and the editing system is performed in FIG. 6 from the virtual reading in FIG. 6A to the virtual recording in FIG. 6E. This seek operation is a relatively short-distance seek operation for several years, for example, as shown in FIG. 6F.

  The buffer memory is not explicitly shown in FIG. 4 described above, but is generally provided in a predetermined manner on the data path. That is, they are provided in the drive control unit 11, the formatter / unformatter unit 12, the recording signal processing unit 13, the reproduction signal processing unit 16, and the like. Where the buffer memory is actually provided in the recording / reproducing apparatus differs depending on the system configuration.

  FIG. 6G shows a transition of an example of the amount of prefetch data accumulated in the reproduction side buffer by the above-described operation. When prefetching is started by the operation of FIG. 6A, prefetch data starts to accumulate in the reproduction side buffer. When a certain amount of data is accumulated in the reproduction side buffer, the decoding process shown in FIG. 6B is started. The decoded signal is output from the output terminal of the recording / reproducing apparatus (FIG. 6C). When the decoding process is started, the prefetch data accumulated in the reproduction side buffer is consumed at a constant speed. As described above, the amount of data in the reproduction side buffer increases during the reproduction operation of the read / write unit 10 (corresponding to the block R in FIG. 6F), and during the period when the reproduction operation by the read / write unit 10 is interrupted. It decreases, and it becomes a pulsation locus like FIG. 6G.

  FIG. 6H shows a transition of an example of the amount of write-back data accumulated in the recording buffer by the above-described operation. The edit data (FIG. 6C) input to the recording / playback apparatus is temporarily stored in the recording side buffer after the encoding process (FIG. 6D), and the amount of write-back data in the recording side buffer increases. When the write-back data amount in the recording-side buffer reaches or exceeds the write unit amount for the optical disc 100 and the read / write unit 10 is ready for recording operation, the write-back data writing operation to the optical disc 100 is started. . The write-back data is written on the optical disc 100 with the data amount for one annual ring being faster than the annual ring time. During the write operation, the amount of data in the recording buffer decreases. Therefore, the data amount in the recording side buffer becomes a pulsation locus as shown in FIG. 6H.

  By the way, when editing is completed, it is necessary to rewrite the header and footer corresponding to the edited clip in order to match the new recording data overwritten in the editing target section with the contents of the header and footer. As an example, when insert editing is performed on a certain clip by destructive editing, the content of the clip is different from that before editing. Therefore, new identification information should be assigned to an identifier unique to a material such as UMID (Unique Material Identifier). In this embodiment, for example, this UMID is recorded in the header as a material identifier. Of course, other information may be used as the material identifier. When changing the material identifier, the header information is also updated.

  FIG. 7 shows an example in which writing to the header and footer is executed after the editing is completed. In FIG. 7 (and FIG. 8 described later), the meanings shown in FIGS. 7A to 7H (FIGS. 8A to 8H) correspond to the above-described FIGS. 6A to 6H, respectively. In FIG. 7, it is assumed that the IN point is designated in the annual ring # 2 and the OUT point is designated in the annual ring # 4 based on the output of the recording / reproducing apparatus (FIG. 7C). That is, the editing data is supplied from the IN point in the middle of annual ring # 2 to the OUT point of annual ring # 4. The edit data supplied from the IN point is encoded and stored as write-back data in the recording side buffer as shown in FIG. 7H as an example. When the amount of write-back data in the recording-side buffer reaches or exceeds the write unit amount for the optical disc 100 and the read / write unit 10 is ready for recording operation, the write-back data writing operation to the optical disc 100 is started. Data in the recording buffer starts to decrease.

  When the writing of the write-back data in the annual ring # 2 to the optical disc 100 is completed, the operation of the read / write unit 10 is shifted to the reproduction operation, the prefetch data is accumulated in the reproduction side buffer, and the period of the annual ring # 3 The edit data is encoded and stored in the recording side buffer. As a result, the amount of write back data in the recording buffer increases while the read / write unit 10 is in the reproducing operation. When the data for the annual ring # 7 is read by the reproduction operation, the operation shifts to the recording operation, the data for the annual ring # 3 is written to the optical disc 100, and the amount of write-back data in the recording buffer memory decreases. When the writing of the data for the annual ring # 3 is completed, the operation is shifted to the reproduction operation, and accumulation of prefetch data for the annual ring # 8 is started. In this example, the write-back data does not increase here because the data up to the OUT point has already been accumulated during the reproduction operation of the annual ring # 7. Then, when the accumulation of the prefetch data for the annual ring # 8 is completed, the operation is shifted to the recording operation, and the write-back data up to the OUT point of the annual ring # 4 is recorded. When there is no write back data in the recording buffer, the editing operation is terminated.

  When the editing operation is completed, the operation of the recording / reproducing apparatus has not yet stopped, and the background data is continuously reproduced (post-roll operation). On the other hand, as described above, after the editing operation is completed, it is necessary to rewrite the header and footer that are changed along with the editing. That is, when the header and footer are rewritten at the end of editing, it is necessary to perform a seek operation up to the header and footer positions and perform a header and footer write operation during the post-roll operation. The header and footer are arranged on the end side of the clip, for example. As illustrated in FIG. 7F, the seek operation from the position where the editing operation is completed to the position of the header and footer may be a long distance.

  During the seek operation, recording and playback operations cannot be performed. On the other hand, reading of prefetch data from the reproduction side buffer is continuously performed during the post-roll operation. Therefore, if the time required for the seek operation is long, all the prefetch data in the playback side buffer is read during the header and footer write operations, causing a buffer underflow in the playback side buffer, and the post-roll operation may be interrupted. There is sex.

  Therefore, in the embodiment of the present invention, the header and footer write operations are delayed until the post-roll operation is completed. In this way, since the prefetch operation can be continued even after the editing is completed, the buffer underflow in the reproduction side buffer during the post-roll operation does not occur, and the post-roll operation can be continued. This is shown in FIG. Until the post-roll operation is completed, the reproducing operation is continued without performing the writing operation of the header and footer. When the post-roll operation is completed, the reproduction operation is also stopped, and the seek operation is performed up to the header and footer writing positions.

  Completion of the post-roll operation can be determined, for example, by the fact that the playback speed has changed after completion of editing due to stop, forward fast forward, reverse fast forward, forward slow playback, reverse slow playback, or the like. In other words, this means that it can be determined that the post-roll operation is continuing during a period in which the playback speed does not change after the end of editing (receiving the EDIT OFF signal). Therefore, the header and footer writing operations are not performed during the period when the playback speed does not change after the editing is completed.

  Further, after receiving the EDIT OFF signal, if the EDIT ON signal is received again before the playback speed changes (for example, the IN point IN ′ in FIG. 8), it is determined that the editing operation is continued, The header and footer writing process is delayed until the subsequent post-roll operation is completed.

  If the prefetch data that can continue to be reproduced is accumulated in the reproduction side buffer memory after the header and footer writing operation is performed after the editing is completed, the header and footer write delay processing as described above is performed. The header and footer writing process may be performed immediately after the editing operation is finished. For example, when the playback speed of the recording medium is high and the capacity of the playback side buffer is sufficiently large, or when the editing end point and the header and footer positions are very close on the recording medium, the header and It is conceivable that the reproduction by the post-roll operation is not interrupted without performing the footer writing delay process.

  In the above description, both the header and the footer are updated. However, this is not limited to this example, and the header according to this embodiment can be used even when only one of the header and the footer is updated. And footer write delay processing can be applied.

  Next, an example of an editing operation applicable to the embodiment of the present invention will be schematically described with reference to the flowcharts of FIGS. 9 and 10, the symbols “A” and “B” indicate that the processing shifts to the corresponding symbols between FIGS. 9 and 10.

  Note that the processing shown in FIGS. 9 and 10 is processing in which, for example, a determination and an execution instruction are made by the system control unit 17 described with reference to FIG. Also, here, the designation of actual IN point and OUT point, and instructions such as playback start and playback end are made using an editing operation unit connected to the recording / playback apparatus, for example, RS-422 as an interface. It shall be performed by 9 pin control. The system control unit 17 controls each unit of the recording / reproducing apparatus in accordance with various control signals supplied from the editing operation unit.

  In FIG. 9, it is assumed that the operation start point has already returned a certain time before the IN point, and the cueing to the pre-roll start point has been completed. In step S10, the reproduction operation (pre-roll operation) from the pre-roll start point is started. Next, it is determined whether or not the editing target is designated based on the edit preset signal indicating the data type or the like to be edited from the editing operation unit (step S11). If not, the process proceeds to step S10. Returned to If the editing target is designated, the process proceeds to step S12, and it is determined whether the editing operation can be executed. If it is determined that the editing operation can be executed, the process proceeds to step S13, and an edit flag that is a response to the edit preset is set in the recording / reproducing apparatus.

  On the other hand, if it is determined in step S12 that the editing operation cannot be executed for some reason, for example, the recording / reproducing apparatus does not support the editing operation itself, the process proceeds to step S26 in FIG. Then, error processing for incapable editing is performed.

  When the edit flag is set in step S13, the phase adjusting operation is performed in steps S14 to S16. The phase adjusting operation is an operation for adjusting, for example, using a frame pulse so that the edited video data and the background video data have a predetermined phase relationship. By the phase adjustment operation, the phases of the edited video data and the background video data are controlled in units of frames. In step S15, it is determined whether the phase adjusting operation is completed and the servo is locked. If it is determined that the phase adjustment operation is not completed and the servo lock is not applied, the process returns to step S14. If it is determined in step S15 that the servo is locked, the process proceeds to step S16, and it is determined whether or not the reproduction speed has been changed. If it is determined that the playback speed has been changed, such as stop, forward fast forward, reverse fast forward, forward slow playback, and reverse slow playback, the process returns to step S14. If there is no change in the reproduction speed, it is determined that the phase adjustment operation is completed, and the process proceeds to step S17.

  In step S17, an EDIT ON signal indicating the editing start point (IN point) from the editing operation unit is on standby. The timing of the EDIT ON signal becomes the timing of the editing start point (IN point), and the recording / reproducing apparatus starts an actual editing operation by this EDIT ON signal. In the next step S18 (see FIG. 10), it is determined whether or not editing is possible. If it is determined that editing is impossible for some reason, the process proceeds to step S26, and an error process for the editing impossible is performed. If it is determined that editing is possible, the process proceeds to step S19, and a process for starting an actual editing operation is performed.

  When the editing start process in step S19 is completed, an actual editing operation is executed in step S20. The editing operation is continuously performed until an EDIT OFF signal indicating an editing end point (OUT point) is received from the editing operation unit (step S21).

  When the EDIT OFF signal is received and the editing operation is completed, the process proceeds to step S22, and a post-roll operation is performed in which the OUT and subsequent points are continuously reproduced in the editing destination AV data.

  It is possible that the EDIT ON signal is received during the post-roll operation and the IN point is specified. In step S23, it is determined whether an EDIT ON signal is received during the post-roll operation. If it is determined that it has been received, the process returns to step S18, and an editing operation based on the received EDIT ON signal is performed.

  On the other hand, if it is determined in step S23 that the EDIT ON signal has not been received, the process proceeds to step S24, and it is determined whether or not the playback speed has been changed. If it is determined that the playback speed has been changed, such as stop, forward fast forward, reverse fast forward, forward slow playback, reverse slow playback, etc., it is determined that the editing operation is complete, and the process proceeds to step S25. Editing completion processing is performed. On the other hand, if it is determined in step S24 that the playback speed has not been changed, the process returns to step S22 and the post-roll operation is continued.

  FIG. 11 shows an example of the edit start process in step S19 described above in more detail. In step S30, restrictions on the replacement process are set. For example, the replacement process itself can be prohibited, or the replacement process can be performed using a predetermined area other than that previously set as a replacement area on the recording medium, such as the marker block described above. In step S30, these processes for the replacement process are performed as necessary.

  In step S31, for example, a starting point for starting signal processing associated with the editing operation for main line video data and audio data, and video data and audio data of auxiliary AV data is calculated, and edited in the next step S32. A block (ECC block) that starts writing back data to the recording medium is calculated. In step S33, based on the processing in steps S30 to S32 described above, the AV data of the editing data and background data is encoded. In addition, the order of the process of the above-mentioned step S30-step S32 is not restricted to this order.

  FIG. 12 shows in more detail an example of the editing execution process in step S20 described above. FIG. 12 mainly shows processing relating to access to the recording medium in the editing execution processing. In step S60, it is determined whether or not the editing operation is continued. If it is continued, the process proceeds to step S61. In step S61, it is determined whether or not a predetermined amount of reproduction data (prefetch data) is secured in the reproduction side buffer. If it is determined that the AV data stored in the reproduction side buffer is less than or equal to the predetermined amount, the process proceeds to step S64, where the reproduction data is read from the disk and stored in the reproduction side buffer.

  On the other hand, if it is determined in step S61 that the reproduction data is secured in the reproduction-side buffer by a predetermined amount or more, the process proceeds to step S62. In step S62, it is determined whether or not the write back data (write back data) stored in the recording side buffer has reached a predetermined amount. If it is determined that the predetermined amount has been reached, the process proceeds to step S63, and the AV data stored in the recording side buffer is written back to the optical disc 100. On the other hand, if it is determined that the write-back data is not stored in the recording buffer by a predetermined amount, the process returns to step S60.

  FIG. 13 shows an example of the post-roll operation in step S22 described above in more detail. FIG. 13 mainly shows processing related to access to the recording medium in the post-roll operation. In parallel with the post-roll operation shown in FIG. 13, AV data decoding processing and encoding processing are performed along with reproduction by post-roll operation and editing operation immediately before the post-roll operation.

  First, in step S40, the end point for ending the signal processing is calculated in the same manner as the signal processing start point calculation processing in step S31 in the editing start processing described in FIG. In the next step S41, a block for completing the writing back of the edited data onto the recording medium is calculated in the same manner as in step S32 in FIG. Then, in the next step S42, the encoding process is stopped. Note that the process of step S42 can be omitted.

  In the next step S43, it is determined whether or not the post-roll operation is continued. If it is determined that the process is not continued, the process proceeds to step S48, the restriction on the replacement process performed in step S30 of FIG. 9 is released, and the post-roll operation is terminated. On the other hand, if it is determined that the post-roll operation is continued, the process proceeds to step S44, and a predetermined amount of reproduction data is secured in the reproduction-side buffer in the same manner as the editing operation process described with reference to FIG. It is determined whether or not it has been done. If it is determined that the AV data stored in the reproduction side buffer is equal to or less than the predetermined amount, the process proceeds to step S47, where the reproduction data is read from the disk and stored in the reproduction side buffer.

  On the other hand, if it is determined in step S44 that a predetermined amount or more of reproduction data is secured in the reproduction side buffer, the process proceeds to step S45. In step S45, it is determined whether there is data to be written back to the recording medium. If it is determined that there is no data to be written back, the process returns to step S43.

  On the other hand, if it is determined in step S45 that there is data to be written back, for example, the writing back of the data to be edited has not been completed, the process proceeds to step S46 and the data is written back to the recording medium. Processing is performed.

  Of the processes described with reference to FIGS. 7 and 8, the determination of whether or not an EDIT ON signal has been received in step S23 and the determination of whether or not the playback speed has been changed in step S24 are actually the post-process described in FIG. This process can be executed in parallel with the roll operation. As an example, if the presence or absence of an EDIT ON signal or a change in playback speed is determined during a post-roll operation, and an EDIT ON signal is received or a change in playback speed is detected, data reading / writing in the post-roll operation is performed. When processing such as processing, encoding, and decoding is completed and an EDIT ON signal is received, the processing returns to step S18. When a speed change is detected, the processing proceeds to step S25. The

  FIG. 14 shows an example of the editing completion process in step S25 described above in more detail. With the editing process, header and footer information is updated, and the editing result is reflected in the header and footer. In step S50, the header and footer are processed, and the updated header and footer are written back to the recording medium. At this time, as described above, the header and footer write-back operations are delayed until the post-roll operation is completed. In the next step S51, processing relating to metadata is performed. For example, the non-time series metadata generated by the metadata processing unit 15 is written in the NRT area of the recording medium.

  In the above description, the present invention has been described as being applied when the optical disc 100 is used as a recording medium. However, the present invention is not limited to this example. In other words, the header and footer write back timing control method in the case of destructive editing according to the present invention can be applied to other randomly accessible disk recording media such as a hard disk.

  In the above description, in the present invention, the recording of the clip is performed in units of annual rings, but this is not limited to this example. Even when the data constituting the clip is recorded in a recording unit other than the annual ring, the header and footer write-back timing control method according to the present invention can be applied.

It is a basic diagram which shows an example data arrangement | positioning in a non-linear recording medium. It is a basic diagram for demonstrating an annual ring structure. It is a basic diagram for demonstrating an annual ring structure. 1 schematically shows a configuration of an example of a recording / reproducing apparatus applicable to the present invention. It is a basic diagram for demonstrating destructive editing by this invention. It is an approximate line figure showing roughly signal processing at the time of destructive editing operation, and a buffer locus. It is a basic diagram which shows roughly the signal processing and buffer locus | trajectory in the case of the example which performed writing with respect to a header and a footer after completion | finish of an edit. It is a figure for demonstrating continuing the reproduction | regeneration operation | movement without performing the write operation of a header and a footer until a post-roll operation | movement is completed. It is a flowchart for demonstrating an example of edit operation applicable to one Embodiment of this invention. It is a flowchart for demonstrating an example of edit operation applicable to one Embodiment of this invention. It is a flowchart which shows an example of an edit start process in detail. It is a flowchart which shows an example of an edit execution process in detail. It is a flowchart which shows an example of a post-roll operation | movement in detail. It is a flowchart which shows an example of an edit completion process in detail.

Explanation of symbols

11 drive control unit 12 formatter / unformatter unit 13 recording signal processing unit 15 metadata processing unit 16 reproduction signal processing unit 17 system control unit 20 clip 21 video data 22A, 22B, 22C, 22D audio data 23 auxiliary AV data 24 metadata 100 optical disc

Claims (5)

Video data, audio data, or real-time metadata corresponding to the video data or audio data is recorded and reproduced using a randomly accessible recording medium, and video data recorded on the recording medium on the recording medium A recording / reproducing apparatus that performs destructive editing on audio data or real-time metadata corresponding to the video data or audio data,
Access control means for controlling time-division writing to and reading from a randomly accessible recording medium;
Buffer means for temporarily storing data read from the recording medium,
When the playback operation is continuously performed after the editing operation for the video data, the audio data, or the video data or the real-time metadata corresponding to the audio data recorded on the recording medium, the data is updated based on the editing. Whether the writing of the header and / or footer to the recording medium is performed immediately after the editing operation or after the reproduction operation is completed, until the writing of the header and / or footer to the recording medium is completed. A recording / reproducing apparatus configured to make a determination based on an amount of data readable from a buffer means. The recording / reproducing apparatus according to claim 1 ,
If there is a possibility that there is no data that can be read from the buffer means before the writing of the header and / or footer to the recording medium is completed, the header and / or footer updated based on the editing is deleted. A recording / reproducing apparatus that judges to perform writing to a recording medium after completion of the reproducing operation. The recording / reproducing apparatus according to claim 1 ,
When writing the updated header and / or footer to the recording medium based on the editing after the reproduction operation is completed,
A recording / reproducing apparatus, wherein the reproducing operation is judged to be completed by changing the reproducing speed of the reproducing operation after the editing operation. The recording / reproducing apparatus according to claim 3 .
After the editing operation, if an editing start point is designated before the playback speed is changed, it is determined that the playback operation is continued, an editing operation based on the editing start point following the playback operation, and the editing operation A recording / reproducing apparatus in which the header and / or the footer are written to the recording medium after the reproducing operation following has been completed. Video data, audio data, or real-time metadata corresponding to the video data or audio data is recorded and reproduced using a randomly accessible recording medium, and video data recorded on the recording medium on the recording medium An editing method in which destructive editing is performed on audio data or real-time metadata corresponding to the video data or audio data,
An access control step for controlling time-division writing to and reading from a randomly accessible recording medium;
Temporarily storing data read from the recording medium in a buffer means,
When the playback operation is continuously performed after the editing operation for the video data, the audio data, or the video data or the real-time metadata corresponding to the audio data recorded on the recording medium, the data is updated based on the editing. Whether the writing of the header and / or footer to the recording medium is performed immediately after the editing operation or after the reproduction operation is completed, until the writing of the header and / or footer to the recording medium is completed. An editing method in which determination is made based on the amount of data that can be read from the buffer means.

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