JP2002208217A - Recording method and recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lower a possibility that identification codes coincide between overwritten data. SOLUTION: A nonvolatile memory 61 is provided in a cassette 6 which houses a magnetic tape 5. OWP(over write protection) codes (identification codes) used for each recording and related information are stored in the nonvolatile memory 61. When starting recording, information such as OWP codes stored in the nonvolatile memory 61 is read to a control part 3, and a next OWP code is selected in the control part 3 according to the read information. Then, the selected OWP code is set in ID data (signal S11) supplied to a circuit 16 to generate and add an ECC(error correction code). Thereby, the OWP code is added to digital data to be recorded. Simultaneously, the stored OWP codes or the like in the nonvolatile memory 61 are rewritten by a signal from the control part 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording method and apparatus suitable for use in, for example, a digital video tape recorder. More specifically, a good identification code is selected when, for example, an identification code that changes for each record is used to prevent a failure due to unerased data during overwriting.

[0002]

2. Description of the Related Art For example, there is a so-called non-tracking method as one of digital data recording methods. That is, in such a non-tracking method, digital data is recorded such that tracks are sequentially formed diagonally along the longitudinal direction of the magnetic tape during recording. At this time, the digital data to be recorded is divided into predetermined units smaller than the data amount to be recorded on one track, and ID data and synchronization data for identification are added to each unit to form a block (hereinafter, referred to as a block). This block is called a synchronous block) and recorded on a magnetic tape.

At the time of reproduction, the digital data recorded on the magnetic tape as described above is read out by scanning the magnetic head at, for example, twice the recording density, and the read digital data is added to each synchronous block. It is possible to rearrange and output the original order based on the ID data. Therefore, according to such a non-tracking method, there is an advantage that the tracking control is not required at the time of reproduction, a servo circuit for the tracking control and the like can be omitted, and the apparatus can be downsized as a whole.

When recording is performed using a magnetic tape as described above, it is necessary to erase previous data and record new data on a magnetic tape on which recording has already been performed. Done. If the data to be further recorded is digital data, the previous digital data can be erased and new digital data can be recorded simply by overwriting the previous data. Therefore, in the above-described non-tracking recording, the device can be further miniaturized by omitting the means for erasing, for example.

However, in general, in a magnetic recording apparatus, so-called clogging, in which recording cannot be performed instantaneously due to adhesion of dust or the like to a magnetic head, may occur. If such a clog occurs during overwriting in the above-described non-tracking type recording, the digital data before the base is left without being erased where the clog occurs. . Therefore, when that part is reproduced, the overwritten digital data and the remaining unerased background digital data are mixed and output.

In the case where the recorded digital data is video data, for example, when the recorded digital data is video data, the failure due to the clog is based on the digital data of the background that has been erased when reproducing and displaying the video based on the overwritten digital data. The image is partially and instantaneously displayed and the image is disturbed. Further, for example, when the recorded digital data is audio data, at the time of reproducing and outputting the audio based on the overwritten digital data, the audio based on the digital data of the unerased background is partially and instantaneously output. Noise.

For this reason, for example, in an existing digital audio tape recorder, when recording audio data, an identification code (Over W) having a different value for each recording as one of the ID data recorded for each synchronous block.
rite Protection code: hereinafter abbreviated as OWP code). At the time of reproduction, the OWP code added to each synchronous block is sequentially detected, and a different OWP code is detected.
Digital data of a synchronous block in which a code is detected is not output, and original data is restored by error correction processing or the like to prevent disturbance in audio output.

[0008] Such an OWP code is used, for example, in MPEG2 (Moving Pic) for compression encoding at the time of tape recording.
In the case of adopting a stream recording method such as the recording coding Experts Group Phase 2), an OWP code having a different value for each recording functions as information indicating that a stream is different, and a joint between streams is used. Can be used as useful information when performing the above processing.
That is, when the OWP code is different, it is determined that the stream has changed, and processing such as resetting data used for inter-frame interpolation can be performed.

[0009]

SUMMARY OF THE INVENTION
By adding the code, for example, it is possible to prevent the occurrence of a trouble due to clogging in the overwriting recording by the non-tracking method. However, when such an OWP code is added, the information amount of the ID data recorded for each of the above-described synchronization blocks is limited, and thus, for example, the number of bits of the OWP code is also limited. Because of this, OW
The value of the P code cannot be changed indefinitely. For example, when the number of bits of the OWP code is 8 bits, a maximum of 25
Only six values can be used.

If the digital data to be recorded is audio data, the recording time for one continuous recording operation is relatively long, for example, a magnetic tape that performs recording for a maximum of about 45 minutes (one side). Thus, the above 256 types of OWP codes could sufficiently cope. On the other hand, when digital data to be recorded is video data, recording is often performed by dividing into fine cuts, and the recording time for one recording is short. Also, the number of times of overwriting on the same magnetic tape by editing dubbing or the like increases, and the possibility that the same value is used again in the above 256 OWP codes increases.

Therefore, in order to avoid reusing the same OWP code, the OWP code of the underlying digital data is read, for example, at the start of recording, and a different OWP code is added to the overwritten digital data. It is possible. However, in this case, for example, when the recording time of the overwritten digital data is longer than the underlying digital data, the OWP code of the underlying digital data at the recording end position is different from the recording start position, and the overwritten digital data is different. There is a possibility that the data coincides with the OWP code of the data.

A method of adding an OWP code of a value generated at random using a random number generator to digital data to be overwritten can be considered. In this case, for example, the number of bits of the OWP code is 8 bits. 1 /
With a probability of 256, there is a possibility that the OWP code added to the overwritten digital data matches the OWP code of the underlying digital data. If a clog occurs in a portion where the OWP code matches, a disturbance such as a disturbance of a video or a noise due to a mixture of the digital data occurs.

This application has been made in view of such a point, and the problem to be solved is that the conventional apparatus uses a finite value for the identification code of the record. When overwriting, it is inevitable that identification codes may match, and if a clog occurs at the part where such identification codes match, image distortion and noise due to the mixture of digital data may occur. It was not possible to prevent the occurrence of a failure such as the above.

[0014]

According to the present invention, an identification code added to recorded data is stored, and the stored identification code is read to select the next identification code. According to this, since the identification code is selected based on the identification code added to the recorded data, the identification code may match between the overwritten digital data and the underlying digital data. Therefore, it is possible to extremely prevent the occurrence of troubles such as video disturbance and noise due to the mixing of digital data, and improve the reliability of recording and reproduction.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The recording method according to the present invention is a recording method for adding an arbitrary identification code to data to be recorded recorded on a recording medium and recording the data. An identification code added to already-recorded data is stored, the identification code stored at the start of recording is read, and an arbitrary identification code added to the data to be recorded is selected.

Further, the recording apparatus of the present invention is a recording apparatus having an identification code adding means for adding an arbitrary identification code to data to be recorded recorded on a recording medium, wherein Identification code storage means for storing an identification code added to the data of the above, and identification code selection for reading out the identification code stored in the identification code storage means at the start of recording and selecting an arbitrary identification code added to the data to be recorded Means are provided.

The present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an embodiment of a recording apparatus to which the recording method and apparatus according to the present invention are applied. That is, FIG. 1 shows an example in which the present invention is applied to a non-tracking type digital video camera 100.

In FIG. 1, a digital video camera 1
For example, an optical lens system and a CCD (Charge Cou
An imaging unit 1 comprising a pled device is provided, and the imaging unit 1 converts an optical image from a subject (not shown) into an electric signal. The converted analog waveform video signal S1 is converted to an A / D conversion circuit 1 constituting the recording signal processing unit 10.
1 and converted into a digital signal.
1 is supplied to the video data encoding unit 12. The encoding unit 12 converts the supplied video data D1 into an MPE
It is compression-coded according to a predetermined standard such as G2.

The analog audio signal S2 picked up by the audio input device 2 such as a microphone is supplied to an A / D conversion circuit 13 constituting the recording signal processing unit 10. Further, the audio data D2 converted into a digital signal by the A / D conversion circuit 13 is supplied to an audio data encoding unit 14. In the coding unit 14, the supplied audio data D2 is compression-coded according to a predetermined standard such as MPEG2. Then, the video data D3 and the audio data D4 compressed and encoded by the encoding units 12 and 14 are supplied to a multiplexer (MUX) 15.

Thus, in the multiplexer 15, the supplied video data D3 and audio data D4 are multiplexed in a predetermined pattern according to the recording format. Further, the multiplexed video / audio data D5 is an error correction code (hereinafter, abbreviated as ECC).
Is supplied to the generation adding circuit 16. The generation addition circuit 16 generates and adds an error correction code such as a Reed Solomon code to the video / audio data D5, and also converts an OWP code supplied from the control unit 3 of the entire apparatus, for example. ID data including the ID is added.

That is, in the generation / addition circuit 16, for example, as shown in FIG.
Or 112 bytes of this video / audio data
2 bytes generated in the vertical direction by combining 160 blocks
For a 112-byte ECC (C2 parity) of 0 block, a 2-byte synchronization pattern (SYN
C) and 4-byte ID data (ID) are added. The ID data includes, for example, a track number, a synchronous block number, reserved data, and an OWP code of 1 byte = 8 bits as shown in FIG. 2B.

Here, the track number of the ID data is, for example, a number which starts from the value "0" and goes to the value "255" for each recording (stream). The synchronous block number is a number indicating the order of the synchronous block in one track recorded on a magnetic tape, for example. Further, these synchronization patterns, ID data and video / audio data (DATA) or ECC (C2 parity)
, A 10-byte ECC (C1
Parity) is added. In this manner, digital data of one synchronous block is formed.

As a result, for example, as shown in FIG. 3, the synchronizing pattern (SYNC) and the ID
Data (ID) and video / audio data (DATA) and EC
160 synchronous blocks composed of C (C1 parity), and 20 synchronous blocks composed of a synchronous pattern, ID data, ECC (C2 parity) and ECC (C1 parity) are sequentially output. And the sum of these 180
As shown in FIG. 4, for example, one track of digital data D6 that is sequentially recorded diagonally along the longitudinal direction of the magnetic tape (recording medium) is formed by the synchronous blocks.

Further, the digital data D6 is output from the generating and adding circuit 16 in accordance with the supply of the video data D3 and the audio data D4 from the encoding units 12 and 14. The output digital data D6 is supplied to a modulation circuit 17 and modulated into an arbitrary RF (Radio Frequency) signal D7, and the modulated RF signal D7 is amplified by the amplifier 1.
8, the data is supplied to a head driver 41 constituting a recording / reproducing system. Further, the RF signal D7 supplied to the head driver 41 is supplied to the magnetic heads 4A and 4B provided on the head drum 42 at an angle of 180 degrees.

On the peripheral surface of the head drum 42, a magnetic tape 5 as a recording medium is pulled out from a cassette 6 and wound obliquely in a predetermined range. The magnetic tape 5 is transferred at an arbitrary speed by a capstan motor 43 via a capstan (not shown), and the head drum 42 is rotated at a predetermined speed by the drum motor 44 so that the head driver 41 The RF signal D7 is, for example, as shown in FIG.
Are recorded so as to form diagonal tracks in the longitudinal direction.

The control signal S10 from the control unit 3 is supplied to the head driver 41, the capstan motor 43, and the drum motor 44 constituting the recording / reproducing system. Switching of the magnetic heads 4A and 4B, rotation of the head drum 42, transfer of the magnetic tape 5, and the like are controlled in accordance with the output of D6. That is, in a recording / reproducing system which involves compression / expansion by encoding, since the recording / reproducing timing is not constant, these controls are performed by a control signal S10 from the control unit 3, for example.

Therefore, the control unit 3, for example, responds to an external operation signal supplied to the input unit 31, for example, by using the memory data used for interpolation between frames due to a change in the stream for each recording. A control signal S11 for performing a reset or the like is sent to the generation and addition circuit 16, and the control signal S11 is supplied to the head driver 41, the capstan motor 43 and the drum motor 44 in accordance with the output of the digital data D6 from the generation and addition circuit 16. A signal S10 is formed. The above-described ID data is sent to the generation / addition circuit 16 while being included in the control signal S11, for example.

At the time of reproduction, for example, the magnetic head 4
The head drum 42 is rotated so that A and 4B scan the tracks on the magnetic tape 5 at twice the recording density. Reproduction signals from the magnetic heads 4A and 4B are supplied to the head driver 41, and the head driver 41
The RF signal D8 extracted through is supplied to the amplifier 21 included in the reproduction signal processing unit 20. Further, the RF signal D8 amplified by the amplifier 21 is supplied to the demodulation circuit 22, and the digital data D9 in the RF signal D8 is demodulated and extracted.

The digital data D9 is supplied to an error correction circuit 23 corresponding to the error correction code (ECC) added by the generation addition circuit 16 of the recording signal processing unit 10.
In the error correction circuit 23, the ECC (C1
Parity data and C2 parity).
Nine error corrections are performed. At the same time, the identification code (OWP code) included in the ID data of the digital data D9 is detected, and the digital data of the detected synchronous block of a different OWP code is not used.
The original data is restored by the above-described error correction processing.

Further, the digital data D10 corrected and restored by the error correction circuit 23 is supplied to a demultiplexer (DEMUX) 24, and the multiplexed digital data is separated by the multiplexer 15 of the recording signal processing unit 10 to separate the video data. Data D11 and audio data D12 are extracted. That is, in the demultiplexer 24, the video data D11 and the audio data D12 are separated according to the format from the digital data restored to the same format as at the time of recording, for example, by the error correction in the error correction circuit 23.

At this time, the control section 3 controls reproduction in response to, for example, an external operation signal supplied to the input section 31 and also controls the error correction circuit 23, for example.
A control signal S10 to be supplied to the head driver 41, the capstan motor 43, and the drum motor 44 is formed according to the timing at which the decompression decoding is performed in the subsequent circuits. Further, for example, the OWP code (signal S12) detected by the error correction circuit 23 is determined, and when a change in the recording stream is detected, for example, a control signal S13 for notifying the circuits subsequent to the demultiplexer 24 is formed. You.

Further, the video data D11 separated by the demultiplexer 24 is supplied to a video data decoding unit 25, and is decompressed and decoded according to a predetermined standard such as MPEG2.
The decoded digital data D13 is supplied to the D / A conversion circuit 2
6 to be converted into an analog waveform video signal S3. The audio data D12 separated by the demultiplexer 24 is supplied to the audio data decoding unit 27,
The digital data D14, which has been decompressed and decoded according to a predetermined standard such as PEG2, is supplied to the D / A conversion circuit 28, where it is converted into an audio signal S4 having an analog waveform.

The converted video signal S3 and audio signal S4 are output as a video output 7 and an audio output 8 respectively.
Is taken out. Thus, the video signal S1 and the audio signal S2 are converted into digital data D7 and recorded on the magnetic tape 5, and the video signal S3 and the audio signal S4 are extracted from the digital data D8 reproduced from the magnetic tape 5. Also, an OWP code is added to the digital data recorded at this time, and an error correction or a process when a recording stream is changed is performed using the OWP code during reproduction.

Further, in this apparatus, the nonvolatile memory 6 is stored in the cassette 6 in which the above-described magnetic tape 5 is stored.
1 is provided. The non-volatile memory 61 stores information unique to the magnetic tape 5 stored in the cassette 6. Therefore, the OWP code provided in the ID data supplied from the control unit 3 to the generation adding circuit 16 at the time of the above-described recording is stored in the nonvolatile memory 61, and the stored OWP code is read out at the start of the recording. Then, the OWP code provided in the ID data supplied to the generation / addition circuit 16 is selected.

That is, in the first embodiment, the OWP code used in each recording is stored in the nonvolatile memory 61. Then, at the start of recording, the OWP code stored in the non-volatile memory 61 is read out to the control unit 3, and the control unit 3 reads out the OWP code of the next value.
The WP code is selected and provided in the ID data supplied to the ECC generation / addition circuit 16. As a result, the OWP code is added to the digital data to be recorded. At the same time, the storage of the OWP code in the nonvolatile memory 61 is rewritten by the signal from the control unit 3.

This situation will be further described with reference to FIG.
In the following description, for simplification, OWP code = 0 to 0
7 (3 bits). Therefore, for example, at the start of recording, FIG.
5A, there are five digital data records on the magnetic tape 5, OWP codes = 0 to 4 are respectively added, and the non-volatile memory 61 has the OWP code = 4 added to the last record. Is stored. Therefore, an OWP code = 5 is added to a signal which is read from this storage and is newly recorded as shown in FIG. 5B, and the OWP code = 5 is stored in the nonvolatile memory 61 at the end of the recording.

According to this, according to the number of OWP codes, different OWP codes can always be selected up to the maximum number. Further, for example, if the OWP code is 8 bits and there are 256 types of codes, it is assumed that the first record has been erased before all of them are used up, and the possibility that the codes match will be extremely low. .
If the non-volatile memory 61 is not used, the entire length of the magnetic tape 5 must be reproduced and detected in order to know the OWP code added to the last recording, and the detection time is enormous. It is difficult to implement.

Therefore, in the first embodiment, the identification code added to the recorded data is stored, and the stored identification code is read out to select the next identification code. Since the identification code is selected based on the identification code added to the data, the possibility that the identification code matches between the overwritten digital data and the underlying digital data can be extremely reduced. , The occurrence of troubles such as disturbance of video and noise can be satisfactorily prevented, and the reliability of recording and reproduction can be improved.

Thus, in the conventional apparatus, since a finite value is used for the identification code of the record, the possibility that the identification codes match at the time of overwriting is unavoidable. According to the present invention, when a clog occurs in a part where a code coincides, it is not possible to prevent a disturbance such as a disturbance of a video or a noise due to a mixture of digital data. The point can be easily eliminated.

Further, in the second embodiment, the OWP code used for each recording in the nonvolatile memory 61 and the absolute track numbers on the magnetic tape 5 at the recording start point and the recording end point at which the recording was performed Is stored. That is, in FIG. 6, for example, when four digital data are recorded on the magnetic tape 5 as shown in FIG. 6A at the start of the recording, and OWP codes = 0 to 3 are added, respectively, The absolute memory 61 stores the absolute track numbers of the start point and the end point of the recording together with the respective OWP codes.

Here, the absolute track number is recorded by providing a predetermined number of bits in a subcode area provided separately from the recording data area in the recording pattern of the track on the magnetic tape 5 shown in FIG. For example, a continuous number is provided for each track from the beginning to the end of the magnetic tape 5. That is, this absolute track number is a unique address on one magnetic tape, and all recording tracks can be specified for each track using this absolute track number.

Therefore, when performing recording by overwriting, the information stored in the non-volatile memory 61 is read out at the start of the recording, and the OWP not used in the previous recording is read out of the read out information. The code is determined. Then, ID data is formed using the determined OWP code, and the formed ID data is included in, for example, the control signal S11 and sent to the generation / addition circuit 16 to be added to digital data to be recorded by overwriting. Is done.
As a result, the OWP code is added to the digital data to be recorded.

That is, in FIG.
When it is determined from the storage of 1 that the OWP code = 2 is not used, as shown in FIG. 6B, the overwriting is performed using the OWP code = 2. When the recording is completed, the absolute track number “450” of the recording start point and the absolute track number “600” of the ending point of the overwriting are stored in the nonvolatile memory 61 together with the OWP code = 2. At this time, the absolute track numbers of the end point and the start point of the recording partially erased by the overwriting recording are changed.

According to this, an unused OWP code can be easily selected at the start of recording. Further, when a previous record is erased by, for example, overwriting, information about the record is also erased from the storage of the non-volatile memory 61 so that the unused OWP is deleted.
It is possible to reduce the possibility that the OWP code is insufficient due to the supplement of the code. If the non-volatile memory 61 is not used, the entire length of the magnetic tape 5 must be reproduced and detected in order to know the unused OWP code, and the detection is enormous, and implementation is difficult. It is.

However, the above-mentioned means cannot completely eliminate the possibility that the OWP code is insufficient. FIG. 7 shows a means for further reducing the possibility that the OWP code is insufficient. That is, FIG.
Recording is performed by overwriting using the OWP code used in each recording stored in 1 and the information of the absolute track number on the magnetic tape 5 at the recording start point and the recording end point where the recording was performed. OWP added to digital data
5 is a flowchart showing a procedure for selecting a code.

In FIG. 7, when the process is started,
First, in step [1], information stored in the nonvolatile memory 61 is read. In step [2], it is determined whether or not there is an unused OWP code in the read information. If there is an unused OWP code (Y), an arbitrary OWP code is selected from the unused OWP codes in step [3]. That is, when there is an unused OWP code in step [2], the selection of the OWP code is performed by the same processing as that shown in FIG.

On the other hand, if there is no unused OWP code at step [2] (N), the track at the recording start position is reproduced at step [4], and the absolute value of the recording start position is obtained from the subcode. The track number is detected. Then, in step [5], it is compared with the information stored in the nonvolatile memory 61, and it is determined whether or not there is an unused OWP code in the recording after the detected absolute track number. When there is an unused OWP code here (Y)
In step [3], an arbitrary OWP code is selected from unused OWP codes in step [3].

That is, in step [5], the unused OWP
For example, as shown in FIG. 8A, although there is a record on the magnetic tape 5 where OWP codes = 0 to 7 are added, a record with OWP codes = 0 and 1 is recorded. Absolute track number “65” at the start position
0 ", and these OWP codes = 0 and 1 are not used in recording after the recording start position. In the description, OWP codes = 0 to 7 for simplicity.
(3 bits). Therefore, in this case, in step [3], for example, unused OWP code = 0 is selected.

Accordingly, in step [11], as shown in FIG. 8B, for example, the selected OWP code =
Recording by overwriting is performed using 0. Then, the end of the recording is determined in step [12]. When the recording is completed (Y), step [13] the non-volatile memory 61 is executed.
The absolute track number "6" of the recording start point by overwriting
50 "and the absolute track number" 1100 "of the end point
Stored with OWP code = 0. At this time, the absolute track numbers of the end point and the start point of the recording partially erased by the overwriting recording are changed.

Further, when there is no unused OWP code after the recording start position in the above step [5] (N), the magnetic tape 5 on which the recording is performed to the value "N" in the step [6]
Is substituted for the maximum absolute track number in step [7].
The absolute track number of the maximum recording start point less than the value "N" is detected from the absolute track numbers of the recording start point and the ending point read from the nonvolatile memory 61 and the OWP code thereof. In step [8], it is determined whether the same OWP code as the OWP code related to the recording start point exists before the previous recording start position.

If the same OWP code exists in step [8] (Y),

In [9], the absolute track number of the recording start point is substituted for the value "N", and the process returns to step [7]. As a result, in step [8], it is determined (N) that the same OWP code as the OWP code related to the detected recording start point does not exist before the previous recording start position. That is, in this step [8], the O used at the farthest position after the recording start point is
A WP code is detected. Then, in step [10], the OWP code is selected.

Thus, for example, as shown in FIG. 9A, if there is a recording with OWP codes = 0 to 7 on the magnetic tape 5 after the recording start position, the magnetic recording is performed in step [8]. It is determined in order from the end of the tape 5 whether or not the OWP code of each recording is present before the previous recording start position, and as a result, for example, the OWP code = 7 used farthest after the recording start point is used. Is detected. Then, in step [10], the OWP code = 7
Is selected. In the description, the OWP code is set to 0 to 7 (3 bits) for simplification.

Accordingly, in step [11], for example, as shown in FIG. 9B, the selected OWP code =
7 to perform recording by overwriting. Then, the end of the recording is determined in step [12]. When the recording is completed (Y), step [13] the non-volatile memory 61 is executed.
The absolute track number “2” of the recording start point by overwriting
00 ”and the absolute track number“ 600 ”of the end point
Stored together with WP code = 7. At this time, the absolute track numbers of the end point and the start point of the recording partially erased by the overwriting recording are changed.

According to this, the OWP can be easily performed at the start of recording.
You can choose the code. If there is no unused OWP code after the recording start position, the most distant OWP code is selected, so that at least [total number of OWP codes-1] recordings are performed up to that point. There are 7 records if the OWP code is 3 bits, and 255 records if the OWP code is 8 bits,
If the recording is the same as before, it is very unlikely that the OWP code of the underlying digital data at the recording end position matches the OWP code of the overwritten digital data.

Therefore, also in the second embodiment, the identification code added to the recorded data is stored, the stored identification code is read, and the next identification code is selected, so that the next identification code is selected. Since the identification code is selected based on the identification code added to the already-existing data, the possibility that the identification code matches between the overwritten digital data and the underlying digital data can be extremely low, and the digital It is possible to satisfactorily prevent the occurrence of troubles such as video disturbance and noise due to the mixing of data, thereby improving the reliability of recording and reproduction.

As a result, in the conventional apparatus, since a finite value is used as the identification code for recording, the possibility that the identification codes match when performing overwriting is inevitable. According to the present invention, when a clog occurs in a part where a code coincides, it is not possible to prevent a disturbance such as a disturbance of a video or a noise due to a mixture of digital data. The point can be easily eliminated.

In the above-described embodiment, the reading and writing of information in the nonvolatile memory 61 are performed by accessing the nonvolatile memory 61 each time recording is performed. The information in the non-volatile memory 61 is read out to the control unit 3 by one access when the cassette is turned on, and the information in the control unit 3 is written into the non-volatile memory 61 when the cassette 6 is ejected or when the power is turned off. You may. According to this, the number of accesses to the nonvolatile memory 61 can be reduced, and the processing can be performed smoothly.

In the above-described embodiment, the OWP code is selected to be a sequentially increasing number. For example, as described in Japanese Patent Application Laid-Open No. 2000-207784, OWP code is used.
By performing a process of sequentially selecting codes whose code length is equal to or more than “2”, it is possible to reduce the possibility that an OWP code is erroneously determined due to a defect at the time of error correction, and to improve the reliability of recording and reproduction. The present invention can be applied to means for further improving.

Further, in the above-described embodiment, information such as the OWP code used in each recording and the absolute track number on the magnetic tape 5 at the recording start point and the recording end point where the recording was performed are stored. Although the non-volatile memory 61 is provided on the cassette 6, for example, when the non-volatile memory 61 on the cassette 6 is provided with only the identification means of the cassette, for example, the control A memory having a size may be provided to collectively hold the information of each cassette, and the information of the cassette may be selected by the above-described identification means.

In the above-described embodiment, the case where the present invention is applied to the non-tracking type digital video camera 100 has been described. However, the present invention is not limited to this. The present invention may be applied to a video tape recorder, and can be widely applied to various other recording devices.

Further, in the above embodiment, the OWP
The video / audio data D7 to which the code is added is
In the above description, the means for recording is composed of the head driver 41, the head drum 42, and the magnetic heads 4A and 4B. However, the present invention is not limited to this, and various other configurations can be widely applied. Things.

In the above-described embodiment, the means for reproducing the recording data D8 recorded on the magnetic tape 5 includes the head driver 41, the head drum 42, and the magnetic head 4.
A and 4B have been described.
The present invention is not limited to this, and various other configurations can be widely applied.

Further, in the above embodiment, the video / audio data D5 is divided in units of 112 bytes,
A case has been described in which the video / audio data D5 in units of 12 bytes is divided into blocks by adding a synchronization pattern (SYNC), ID data (ID), and the like. However, the present invention is not limited to this. The present invention can also be widely applied to a case where the video / audio data D5 is divided into blocks other than the above and divided into blocks.

Thus, according to the recording method described above, a recording method in which an arbitrary identification code is added to data to be recorded to be recorded on a recording medium and recording is performed. The stored identification code is stored at the start of recording, and the stored identification code is read out to select an arbitrary identification code added to the data to be recorded. Can reduce the possibility of matching identification codes, and can prevent the occurrence of disturbances such as video disturbance and noise caused by digital data mixing, and improve the reliability of recording and reproduction. That can be done.

The above-mentioned recording apparatus is also a recording apparatus having an identification code adding means for adding an arbitrary identification code to data to be recorded recorded on a recording medium. Identification code storage means for storing an identification code added to data, and identification code selection means for reading an identification code stored in the identification code storage means at the start of recording and selecting an arbitrary identification code to be added to data to be recorded Is provided, it is possible to extremely reduce the possibility that the identification code matches between the overwritten digital data and the underlying digital data, and the disturbance of the image and noise due to the mixing of the digital data. Can be satisfactorily prevented, and the reliability of recording and reproduction can be improved.

The present invention is not limited to the above-described embodiment, but can be variously modified without departing from the spirit of the present invention.

[0067]

According to the first aspect of the present invention, the identification code added to the recorded data is stored, and the stored identification code is read to select the next identification code. Since the identification code is selected based on the identification code added to the recorded data, the possibility that the identification code matches between the overwritten digital data and the underlying digital data can be extremely reduced. In addition, it is possible to satisfactorily prevent the occurrence of troubles such as disturbance of video and noise due to mixing of digital data, thereby improving the reliability of recording and reproduction.

According to the second aspect of the present invention, the identification code is stored in the non-volatile memory provided in the storage box of the recording medium, so that the identification code can be selected very easily. It is.

According to the third aspect of the present invention, the storage of the identification code is performed by the storage means provided in the apparatus main body, and the provision of the means for identifying the recording medium makes the selection of the identification code extremely easy. This can be performed, and the storage means provided on the recording medium can be simplified.

According to the fourth aspect of the present invention, the identification code is selected by selecting the identification code in the order next to the stored identification code used in the previous recording.
The selection of the identification code can be performed very easily.

According to the fifth aspect of the present invention, the identification code is selected to be recorded on the recording medium this time according to the stored identification code used in the previous recording and its recording position. By selecting from the identification codes not used in the position, it is possible to prevent the shortage of the identification codes from occurring.

According to the sixth aspect of the present invention, the selection of the identification code is performed by selecting the stored identification code not used in the previous recording or the stored identification code used in the previous recording. An identification code that is not used after the current recording start position on the recording medium according to the recording position, or the identification code used in the previous recording stored and the current identification code that is used according to the recording position. By selecting from the identification codes used farthest after the recording start position, the possibility that the identification codes match can be almost eliminated.

According to the seventh aspect of the present invention, the identification code added to the recorded data is stored, and the stored identification code is read to select the next identification code. Since the identification code is selected based on the identification code added to the already-existing data, the possibility that the identification code matches between the overwritten digital data and the underlying digital data can be extremely low, and the digital It is possible to satisfactorily prevent the occurrence of disturbances such as image disturbance and noise due to data mixing, thereby improving the reliability of recording and reproduction.

According to the eighth aspect of the present invention, the identification code storage means comprises a non-volatile memory provided in the storage box of the recording medium, so that the identification code can be selected very easily. It is.

According to the ninth aspect of the present invention, the identification code storage means is a storage means provided in the main body of the apparatus, and the means for identifying the recording medium is provided, so that the identification code can be selected very easily. This can be performed, and the storage means provided on the recording medium can be simplified.

According to the tenth aspect of the present invention, the identification code selection means selects the identification code in the next order from the identification code used in the previous recording read from the identification code storage means. The selection of the identification code can be made very easily.

According to the eleventh aspect of the present invention, the identification code selecting means stores the recording medium in accordance with the identification code read from the identification code storage means and used in the previous recording and its recording position. By selecting from the identification codes not used at the position to be recorded this time, it is possible to prevent the shortage of the identification codes from occurring.

According to the twelfth aspect of the present invention, in the identification code selection means, the identification code unused in the previous recording read from the identification code storage means or read from the identification code storage means is used. Depending on the identification code used in the previous recording and its recording position, an unused identification code after the current recording start position on the recording medium or the previous recording read from the identification code storage means. Eliminating the possibility that the identification codes match by selecting from the identification codes used farthest after the current recording start position on the recording medium according to the identification codes used and their recording positions Can be done.

Thus, in the conventional apparatus, since a finite value is used as the identification code for recording, the possibility that the identification codes match when overwriting is inevitable. According to the present invention, when a clog occurs in a part where a code coincides, it is not possible to prevent a disturbance such as a disturbance of a video or a noise due to a mixture of digital data. The point can be easily eliminated.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of a recording apparatus to which a recording method and apparatus according to the present invention are applied.

FIG. 2 is a configuration diagram of one synchronization block of the recording data.

FIG. 3 is a configuration diagram of a synchronization block in one track.

FIG. 4 is a configuration diagram showing a pattern of a recording track.

FIG. 5 is a diagram for explaining the first embodiment.

FIG. 6 is a diagram for explaining a second embodiment.

FIG. 7 is a flowchart for explaining the operation.

FIG. 8 is a diagram for explaining a second embodiment.

FIG. 9 is a diagram for explaining a second embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Image pick-up part, 2 ... Voice input device, 3 ... Control part,
4A, 4B: magnetic head, 5: magnetic tape, 6: cassette, 7: video output, 8: audio output, 10: recording signal processing unit, 11, 13: A / D conversion circuit, 12: video data encoding unit .. 14 audio data encoding unit, 15 multiplexer, 16 error correction code generation / addition circuit, 17 modulation circuit, 18, 21 amplifier, 20 reproduction signal processing unit, 2
2 demodulation circuit, 23 error correction circuit, 24 demultiplexer, 25 video data decoding unit, 26, 28 D /
A conversion circuit, 27: audio data decoding unit, 31: input unit, 41: head driver, 42: head drum, 43
... Capstan motor, 44 ... Drum motor, 100 ...
Digital video camera

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) H04N 5/92 H04N 5/92 HF term (reference) 5C018 HA08 5C053 FA21 GB05 GB15 GB38 KA05 LA01 5D044 AB05 AB07 BC01 CC03 DE02 DE03 DE17 DE49 DE52 EF05 5D110 AA04 DA04 DB08 DC01 DC16 DD01 DE04

Claims (12)

[Claims] 1. A recording method for performing recording by adding an arbitrary identification code to data to be recorded recorded on a recording medium, wherein the identification added to data recorded on the recording medium is provided. A recording method comprising: storing a code; reading out the stored identification code at the start of recording; and selecting the arbitrary identification code to be added to the recording target data. 2. The recording method according to claim 1, wherein the identification code is stored in a non-volatile memory provided in a housing of the recording medium. 3. The recording method according to claim 1, wherein the storage of the identification code is performed by a storage unit provided in the apparatus main body, and a unit for identifying the recording medium is provided. 4. The recording method according to claim 1, wherein the selection of the identification code includes selecting an identification code next to the stored identification code used in the previous recording. 5. The selection of the identification code is not performed at the position to be recorded this time on the recording medium according to the stored identification code used in the previous recording and the recording position thereof. 2. A recording method according to claim 1, wherein the recording method is selected from an identification code. 6. The selection of the identification code is performed according to the stored identification code unused in the previous recording or the stored identification code used in the previous recording and its recording position. The current recording start position on the recording medium according to the identification code unused after the current recording start position on the recording medium or the stored identification code used in the previous recording and its recording position. 2. The recording method according to claim 1, wherein the identification code is selected from an identification code used farthest after the position. 7. A recording apparatus having an identification code adding means for adding an arbitrary identification code to data to be recorded recorded on a recording medium, the recording apparatus comprising: Identification code storage means for storing the identification code; identification code selection means for reading the identification code stored in the identification code storage means at the start of recording and selecting the arbitrary identification code to be added to the recording target data; A recording device, comprising: 8. The recording apparatus according to claim 7, wherein said identification code storage means comprises a non-volatile memory provided in a housing for said recording medium. 9. The recording apparatus according to claim 7, wherein said identification code storage means is storage means provided in an apparatus main body, and further comprises means for identifying said recording medium. 10. The identification code selection means, wherein the identification code next to the identification code used in the previous recording read from the identification code storage means and selected is selected. Recording device. 11. The identification code selection means attempts to record the current time on the recording medium in accordance with the identification code read from the identification code storage means and used in the previous recording and its recording position. 8. The recording apparatus according to claim 7, wherein the identification code is selected from unused identification codes. 12. The identification code selection means, wherein the identification code read from the identification code storage means and used in the previous recording is unused, or the identification code used in the previous recording read from the identification code storage means is used. The unused identification code after the current recording start position on the recording medium, or the identification used in the previous recording read from the identification code storage means, according to the identification code and its recording position. 8. The recording apparatus according to claim 7, wherein an identification code used farthest after the current recording start position on the recording medium is selected according to the code and its recording position.