JPH03250468A - Video tape recorder - Google Patents

Abstract

PURPOSE:To ensure the recording of a recording signal by storing a position of a recording area and a recording signal to be recorded in this area when a recording error is generated in a 1st recording mode, executing the rerecording mode after the recording mode is finished and recording newly the signal in the recording area where the error took place. CONSTITUTION:When a recording error is generated in a normal recording mode, a time code for that track and a data to be recorded there are stored in an address memory 21A and a storage device 15. Then, at timing of the arrival of the error generated track while traveling a magnetic tape 1 after rewinding the tape 1, the recording signal is newly recorded on this track based on the data of the circuit 15. By this method, the correct recording signal is overwritten on the error generated track, so that an error area concerned is supplemented to ensure the recording of the recording signal.

Description

[Detailed description of the invention] The present invention will be explained in the following order.

A: Industrial field of application B: Overview of the invention C: Prior art (Figs. 3 to 7) D: Problem to be solved by the invention E: Means for solving the problem (Figs. 1 and 2) F Effect (FIGS. 1 and 2) G Embodiment (FIGS. 1, 2, 4, and 7) H Effect of the invention A Industrial field of application The present invention relates to a video tape recorder, and in particular It is suitable for application to a video tape recorder (VTR) that records digital video signals and digital audio signals on magnetic tape.

B Summary of the Invention The present invention provides, in a video tape recorder, when a recording error occurs in a recording signal recorded on a recording medium in a first recording mode, a re-recording mode is executed to record a part of the recording error. By re-recording the signal, the recorded signal can be reliably recorded.

C. Prior Art Conventionally, in a video tape recorder (digital VTR) for recording and reproducing digital video signals, for example, a third
As shown in the figure, a recording signal S RlC consisting of a digital video signal and a digital audio signal sent out from the recording circuit 3 via the recording head 4A is sequentially recorded on the magnetic tape 1 running in the direction indicated by arrow a, and By immediately reproducing the reproduced signal S□ read out through the subsequent reproducing head 5A in the reproducing circuit 6, it is possible to monitor whether the digital signal is being recorded correctly.

Furthermore, it has been proposed that during reproduction, the reproduced signal is temporarily stored, the recorded signal on the magnetic tape 1 is erased, and the stored reproduced signal is rewritten (in particular, Publication No. 56-156975).

Here, on the magnetic tape 1, as shown in FIG. 4, tracks TRI are sequentially arranged at a track pitch TP.
, TR2, ......, six tracks TR
The digital video signal and digital audio signal for one field are divided into six, with I to TR6 as one set, and are allocated to each track TRI to TR6 for recording.

Each of the tracks TRI to TR6 is divided into an area ARV for recording digital video signals (this is called a video area) and an area ARA for recording digital audio signals (this is called an audio area).

As shown in FIG. 5, the video area ARV includes, for example, recording areas (this is called a sync plotter) SBV 1 to 5.
It is subdivided into BVk, and each sync block records a sync pattern, ID pattern, data block, and error control data.

Furthermore, the audio area ARA is divided into, for example, four channel areas ARA1 to ARA4, and as shown in FIG.
In the same way as in the case of the video area ARV, n sync blocks 5BAtl to 5BAtn (t=1.2.3.4)
The four channels of digital audio signal data are allocated to the sync blocks of each channel area and recorded.

In a digital VTR configured to record and reproduce digital video signals and digital audio signals on the magnetic tape 1 having such a format, the seventh
A rotating drum 7 having the configuration shown in the figure is used.

That is, the rotating drum 7 has the magnetic tape 1 wound around the circumferential side surface 7A by guide posts 8A and 8B.
The magnetic tape 1 runs in the direction indicated by the arrow a, and the rotating drum 7 rotates in the direction already indicated by the arrow.

This rotary drum 7 has four recording/reproducing systems, and a total of four recording/reproducing systems similar to the first recording/reproducing system consisting of the recording head 4A and the reproducing head 5A described above with reference to FIG. 3 are provided. There is.

That is, on the circumferential side 7A of the rotating drum 7, there is a track TRI.
A recording head 4A for scanning (FIG. 4) is provided.
A reproducing head 5 that reproduces and scans the track TR1 following the
A is arranged to constitute a first recording/reproducing system.

Further, a recording head 4B and a reproducing head 5B are arranged as a second recording/reproducing system, which sequentially scan the track TR2 with a deviation from the recording head 4A and the reproducing head 5A by a track pitch TP, respectively.

Furthermore, a recording head 4C and a reproducing head 5C are arranged as a third recording/reproducing system at positions separated by an angular interval of 180 degrees from the recording head 4A and reproducing head 5A, respectively, so as to sequentially scan the tracks TR, 3. At the same time, the track T is shifted by the track pitch TP with respect to the recording head 4C and the playback head 5C.
Recording head 4D and reproducing head 5D sequentially scanning R4
is arranged as a fourth recording/reproducing system.

In this way, four systems of recording and reproducing systems are formed in the rotating drum 7, and while the rotating drum 7 makes half a revolution, the recording head 4
After tracks TR1 and TR2 are scanned for recording by A and 4B, recording heads 4C and 4D are moved during the subsequent half rotation.
Tracks TR3 and TR4 are scanned for recording, and during further half-rotation, tracks TR5 and TR6 are scanned by recording heads 4A and 4B.

Therefore, every time the rotating drum 7 rotates 1.5 times, one field's worth of digital video signals and digital audio signals are sequentially recorded on the tracks TRI to TR6.

On the other hand, the reproducing heads 5A and 5B are
The tracks TRI and TR2 scanned by the recording heads 4A and 4B are scanned by the recording heads 4A and 4B.
and 4B immediately reproduce and monitor the recording signal recorded by the reproduction heads 5C and 5D.
scans the tracks TR3 and TR4 scanned by the recording heads 4C and 4D following the recording heads 4C and 4D,
The recording signals recorded by the recording heads 4C and 4D are immediately reproduced and monitored.

In this way, the recording heads 4A to 4D sequentially record the digital video signal and the digital audio signal on the tracks TRl to TR6 of the magnetic tape 1, and the subsequent playback heads 5A to 5D correctly record the digital video signal and digital audio signal. It is possible to monitor whether or not there are any

D Problems to be Solved by the Invention By the way, in a digital VTR having such a configuration, the recording heads 4A to 4D scan the magnetic tape 1 while slidingly contacting the magnetic tape 1 and the recording heads 4A to 4D.
Foreign matter such as dust gets caught between the recording heads 4D, causing a so-called dropout in which recorded data is partially lost, or foreign matter such as dust gets caught in the head gap of the recording heads 4A to 4D, causing the recorded data to become continuous. There is a problem in that so-called clogs that are missing occur and the reproduced image and reproduced sound deteriorate.

The present invention has been made in consideration of the above points, and it is an object of the present invention to propose a video tape recorder that can prevent the loss of recorded data and avoid deterioration of reproduced images and reproduced sounds.

Means for solving the problem between points E and U In order to solve this problem, in the present invention, in the first recording mode in which a predetermined recording signal S0C is recorded on the recording medium 1, a recording area in which a recording error has occurred is Position information and correct recording signal S□ to be recorded in the corresponding recording area,
is stored in the predetermined storage means 21A, 15, and the recording signal Sll! is read out from the storage means 15 in the recording area where the recording error has occurred after the first recording mode ends. '.

Enables re-recording mode to be used for supplementary recording.

F action The positional information of the area where a recording error has occurred in the first recording mode and the recording signal to be recorded in the recording error area are stored in the storage means 21A, 15, and the first
By executing the re-recording mode after the recording mode ends and recording the recording signal stored in the storage means 15 in the recording error area, the recording error area can be complemented.

G example An embodiment of the present invention will be described in detail below with reference to the drawings.

In FIG. 1, in which parts corresponding to those in FIG. 3 are given the same reference numerals, the video tape recorder 10 inputs the time code TC sent from the time code generation circuit 11 to the recording circuit 3 in the normal recording mode. Accordingly, the recording signal SIEI: consisting of a digital video signal and a digital audio signal sent from the recording circuit 3 is attached with the time code TC and sent to the encoder 12, and the encoder 12 encodes it. Thereafter, the data is recorded on the magnetic tape 1 running in the direction indicated by the arrow a through the recording head 4A, and is sent through the delay circuits 13 and 14 to the decoder 17 and the storage circuit 15 having a frame memory configuration.

Here, the reproduction signal S read out via the reproduction head 5A
□ is compared with the recording signal S0C sent from the delay circuit 13 in the decoder 17.

That is, the delay circuit 13 is configured to delay the recording signal S□ by a time corresponding to the running speed of the magnetic tape 1 and the interval between the recording head 4A and the reproducing head 5A, and send it to the decoder 17. The decoder 17 compares the reproduced signal S□ obtained by reproducing the signal once recorded on the magnetic tape 1 via the recording head 4A with the recorded signal S0° inputted without being recorded on the magnetic tape 1. If a recording error occurs in the signal recorded on the magnetic tape 1, it can be detected.

If the playback signal S□ and the recording signal S*IC match, it is determined that no recording error has occurred, and the playback signal S□
The demodulated signal S_DEC obtained by demodulating is sent to the following reproducing circuit 6.

On the other hand, if the reproduced signal S- and the recorded signal 5ttc do not match, it is determined that a recording error has occurred, and a recording error detection signal s i indicating that the recording error has occurred is determined.
vy is sent to a control circuit 21 having a microcomputer configuration.

When the recording error detection signal 5DtT is input, the control circuit 21 inputs the current time code TC from the time code generation circuit 11, and also inputs the time code TC at this time.
The time code of the track where the recording error has occurred is calculated based on the time code, and this is stored in the address memory 21A.

At the same time, the control circuit 21 also stores the recording signal S+txc sent from the delay circuit 14 in the first memory area of the storage circuit 15 by sending the write signal Sh to the storage circuit 15 .

Here, the delay circuit 14 outputs the recording signal S□0 for one track where the recording error has occurred at the timing when the write signal Sw based on the recording error is input from the control circuit 21 to the storage circuit 15. The data is sent to a storage circuit 15.

Therefore, the storage circuit 15 stores one track's worth of data (including time code TC) that should be stored on the track where the recording error occurred on the magnetic tape 1.

In this way, correct recording signals S□ are sequentially stored in the memory area of the storage circuit 15 for each track in which a recording error has occurred in the normal recording mode.

When the normal recording mode ends, the video tape recorder 10 rewinds the magnetic tape 1, and then the system controller (not shown) sends a correct recording signal SO to all tracks in which recording errors have occurred, as shown in FIG.
This is executed by switching to the re-recording mode in which C is written again.

That is, in the re-recording mode, the reproducing head 5A is moved while the magnetic tape 1 is running again in the direction shown by the arrow a.
After inputting the reproduction signal S□ from the magnetic tape 1 to the time code reproduction circuit 23 and reading out the time code TC recorded on the magnetic tape 1, this is sent to the control circuit 2.
Send to 1.

At this time, the control circuit 21 controls the recording head 4A based on the time code TC input from the time code reproduction circuit 23.
calculates the timecode of the track you are actually scanning.

If there is a time code that matches the calculated time code among the time codes of the tracks in which the recording error has occurred stored in the address memory 21, the track that the recording head 4A is about to scan at this time is recorded. It is determined that this is the track in which an error has occurred, and a continuation signal SR is sent to the storage circuit 15.

At this time, when the memory circuit 15 receives the read signal SII,
Recording signal S1 for one track stored in the first recording area. (that is, the signal recorded on the track scanned by the recording head 4A at this time) and sends it to the recording head 4A via the amplifier circuit 25. Recording signal S□. Record it again.

At the same time, by sending the time code TC of the recorded data read from the storage circuit 15 to the control circuit 21,
At this time, the control circuit 21 checks whether the recording signal recorded by the recording head 4A is a signal that should be recorded on the corresponding track.

When the re-recording track is scanned for reproduction by the re-recording head 5A, the time code TC included in the re-recorded signal is reproduced via the time code reproducing circuit 23, and the decoder 17 reproduces the time code TC included in the re-recorded signal. To detect whether a recording error has occurred in a recorded signal.

Here, the time code TC is played correctly, and
If no recording error is detected, the control circuit 21 determines that the recording signal S□ is correctly recorded on the re-recorded track, and deletes the time code of the track stored in the address memo 1721A. .

On the other hand, time code TC is not played and
Recording error detection signal S indicating that a recording error has occurred
, T, the control circuit 21 determines that a recording error has occurred again in the re-recorded track, and stores the time code TC of the track stored in the address memory 21A without deleting it. Retain state.

In this way, when the re-recording operation of re-recording the signals to be recorded from the sequential storage circuit 15 on the track where a recording error has occurred in the normal recording mode is completed, the address memory 21A of the control circuit 21 is stored in the address memory 21A of the control circuit 21 in the corresponding re-recording mode. In addition, the time code TC representing the track in which the recording error has occurred still remains, and in the frame memory 15, correct recording data to be recorded on the relevant track is sequentially stored in the memory area for each track.

Therefore, in this case, by further rewinding the magnetic tape 1 and executing the re-recording mode, the correct recording signal 5lIC is recorded on the track where the recording error has occurred.

In this way, by supplementarily recording the recording signal smtc on the track where a recording error has occurred, it is possible to prevent recording errors from remaining on each track.

Here, in the video tape recorder 10, as described above with reference to FIG.
A total of four recording and reproducing systems having the same configuration as the recording and reproducing system having the configuration described above with reference to FIGS. 1 and 2 are provided.

Therefore, the recording head 4A and reproduction head 5A constitute the first recording and reproduction system, the recording head 4B and reproduction head 5B constitute the second recording and reproduction system, and the recording head 4C and reproduction head composing the third recording and reproduction system. Recording signals are sequentially recorded on tracks TRI, TR2, . . . by the head 5C and a recording head 4D and a reproducing head 5D constituting a fourth recording and reproducing system.

Further, as a means for switching between the normal recording mode described above with reference to FIG. 1 and the re-recording mode described above with reference to FIG. (not shown) for switching control.

In the above configuration, the video tape recorder 10 stores all the time code TC and data of the track where the recording error occurred at the time when the normal recording mode ends, and further rewinds the magnetic tape l and executes the re-recording mode. By doing so, the recording signal S0° is supplementarily recorded again on the track where the recording error has occurred.

Therefore, at the time when the re-recording mode ends, the correct recording signal S□ for one track should be recorded on the track where the recording error occurred.

are recorded overlappingly.

Therefore, a correct recording signal S□ is applied to a track where recording data is missing due to a recording error. By supplementing with , it is possible to prevent some recording errors from remaining.

At this point, when the re-recording mode ends, the control circuit 2
If the time code TC remains in the address memory 21A of No. 1, this indicates that a recording error has occurred on the track overwritten with data in the re-recording mode, and at this time, the video tape recorder 10 The re-recording mode is executed again to record the recording signal 5txc on the track where the recording error has occurred.

By repeating the re-recording mode in this manner, recording error portions are compensated for to a practically sufficient extent in the tracks on the magnetic tape 1, thereby preventing deterioration of the reproduced image obtained by reproducing the recorded data.

According to the above configuration, after the time code of the track in which a recording error occurred in the normal recording mode and the data to be recorded on the track are stored in the address memory 21A and the storage circuit 15, the magnetic tape 1 is rewound and the magnetic tape is re-magnetized. While running the tape 1, the recording signal S□ is re-recorded on the track at the timing when the track where the recording error has occurred based on the data in the storage circuit 15, so that the track where the recording error has occurred is recorded. It is possible to overwrite the correct recording signal, thereby complementing the recording error area and reliably recording the recording signal S□.

In this way, when reproducing the recorded data, it is possible to prevent the reproduced image from deteriorating.

By the way, by rewinding the magnetic tape 1 and rerecording the recording signal on the track where the recording error occurred, there is no need to add a recording head for re-recording.
Re-recording can be performed on a track where a recording error has occurred without complicating the overall configuration.

In the above-mentioned embodiment, a case has been described in which data according to the recording signal SREC is stored in the storage circuit 15 for each track, and an area where a recording error has occurred on the magnetic tape is supplementally recorded for each track. However, the present invention is not limited to this, and other data units may be used, such as storing and complementing each sync block.

Furthermore, in the above embodiment, a case has been described in which one field of digital video signal is divided into six tracks and recorded, but the number of divisions is not limited to this, and one field of data may be divided by another number of divisions. You can also do it.

Furthermore, in the above embodiment, the present invention is applied to a digital VTR having a rotating drum with four recording/reproducing systems, but the present invention is not limited to this. digital VTR,
Furthermore, it can be widely applied to fixed head type magnetic recording devices.

Further, in the embodiments described above, the present invention is applied to digital V
Although the case where it is applied to TR has been described, the present invention is not limited to this, and the present invention is also applicable to a magnetic recording device that records recording signals on recording tracks on a magnetic tape, and further to recording recording signals on a recording medium such as a magneto-optical tape. The present invention can be widely applied to other recording devices configured as described above.

H Effects of the Invention As described above, according to the present invention, the position information of the recording area where a recording error occurred in the first recording mode and the recording signal to be recorded in the recording area are stored, By executing the re-recording mode after the recording is completed and recording the recording signal again in the recording area where the recording error has occurred, it is possible to realize a video tape recorder that can reliably record the recording signal.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the video tape recorder according to the present invention, FIG. 2 is a block diagram showing its re-recording mode, FIG. 3 is a block diagram showing a conventional example, and FIG. 4 is a block diagram showing an embodiment of the video tape recorder according to the present invention. 5 is a route map showing the arrangement of the video area, FIG. 6 is a route map showing the arrangement of the audio area, and FIG. 7 is a route map showing the configuration of the rotating drum. 1... Magnetic tape, 4A, 4B, 4G, 4D.
... Recording head, 5A, 5B, 5C15D...
...Playback head, 10...Video tape recorder, 12...Encoder, 13.14...
...Delay circuit, 15...Memory circuit, 17...
... Decoder, 21 ... Control circuit, 21A
... Address memory, 23 ... Time code reproduction circuit.

Claims (1)

[Claims] In a first recording mode in which a predetermined recording signal is recorded on a recording medium, position information of a recording area where a recording error has occurred and a correct recording signal to be recorded in the recording area are stored in a prescribed storage means. and after the first recording mode is completed, a re-recording mode is executed in which the recording signal read from the storage means is complementary recorded in the recording area where the recording error has occurred. A videotape recorder with special features.