JP3218646B2 - Digital recording and playback device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital recording / reproducing apparatus effective for use in a video tape recorder.

[0002]

2. Description of the Related Art In a helical scan type digital recording / reproducing apparatus for recording / reproducing digital data obtained by digitizing a video signal and an audio signal on a recording track inclined in a longitudinal direction on a magnetic tape by a rotary head, a huge amount of information is obtained. In order to record the data, instead of recording one field or one frame of data on one track, m frames of data are divided into n tracks and recorded.
I was playing. Therefore, the control of the capstan, in which the data on the magnetic tape is fed little by little at the time of special playback such as frame advance, slow motion, etc., is performed by using a JOG dial or the like which can freely control the speed of the capstan, by using a continuous slow speed slower than normal playback. The magnetic tape is sent little by little, and during that time, a plurality of tracks on the magnetic tape are scanned many times by the magnetic head, and each time the n-track data obtained from the magnetic head is stored in the memory of the signal processing circuit and stored in the memory. The picture was output when one field of data was stored.

FIG. 3 is a diagram showing a configuration of a conventional digital recording / reproducing apparatus. In FIG. 3, 1 is a signal processing circuit, 2 is a memory for storing data, 3 is a system controller, 4 is a servo circuit for controlling a motor, 5 is a cylinder, 6 is a rotary head, 7 is a capstan, 8 is a magnetic tape, Reference numeral 9 denotes a bus for communication between the blocks, reference numeral 10 denotes a switch for selecting various modes, reference numeral 11 denotes a JOG dial capable of freely controlling the speed of the capstan, and reference numeral 12 denotes a JOG dial operation permission button.

FIG. 4 is a diagram showing a state in which a rotary head scans on a magnetic tape during slow reproduction. Here, the description is made on the assumption that the number of tracks in one frame is five. In FIG. 4, reference numeral 21 denotes the trajectory of the head for normal reproduction, and reference numeral 22 denotes the trajectory of the head during slow motion.

FIG. 5 is a diagram showing the movement of the capstan and the flow of data from the magnetic tape to the memory. In FIG. 5, (a) shows the speed change of the capstan,
(B) is the amount of data in the memory, 33 is the amount of data for one field, and 34 is the timing at which the data for one field is accumulated.

In the figure, from the normal reproduction state, the user performs an operation to enter a mode in which the JOG dial 11 can be operated by using the JOG dial operation permission button 12 of the various mode changeover switch 10. The system controller 3 operates the changeover switch 10 with the JOG dial operation permission button 1
2, the capstan 7 is transmitted to the servo circuit 4 for controlling the motor using the communication bus 9 between the blocks so that the capstan 7 is set to the JOG dial operation mode.
When the capstan 7 enters the JOG dial operation mode, the system controller 3 puts the JOG dial 11 into a mode in which it can be actually operated. The user operates the JOG dial 11 after confirming that the mode has become a mode in which the JOG dial 11 can be actually operated. Upon receiving a signal from the JOG dial 11, the system controller 3
Is the servo circuit 4 using the communication bus 9 between each block.
To the capstan 7 to rotate at a lower speed than usual. While the capstan 7 is rotating at a low speed, the rotating head 6 continues to pick up data on the magnetic tape 8.

However, since the capstan 7 is rotating at a lower speed than the normal reproduction, the rotating head 6 and the magnetic tape 8 are rotated.
Is no longer normal, and the scanning of the rotary head 6 extends over a plurality of tracks on the magnetic tape 8, and a state in which data can be partially picked up for each track continues. The data on the magnetic tape 8 picked up by the rotary head 6 is sent to the signal processing circuit 1, and the data is transferred therefrom to the memory 2 for storing data. The data is stored little by little in the memory 2, and when the data of one field is stored in the memory 2,
One of you output as a screen. Store data for one field
To scan, perform multiple scans as shown in FIG.
Data until the amount of data for one field is accumulated
Need to be moved to memory. User until the screen is output, continue to operate little by little the JOG dial 11 while watching the output screen until the output screen switches. When the user confirms that the output screen has been switched, frame forwarding for one field is completed, and the user stops the operation of the JOG dial 11 or, if necessary to advance by another field, similarly. Operate the JOG dial.

[0008]

However, the conventional configuration described above has the following problems.

In the prior art, the frame feed operation is performed in such a manner that a control circuit such as a servo or a system controller operates independently of a signal processing circuit. Is the only way to make a judgment by looking at the output screen, that is, it can only be realized by operating the JOG dial or the like.
A simple operation for the user, such as sending by the field, has not been realized.

The present invention has been made in view of the problems of the prior art, and
In a digital recording / reproducing apparatus which performs recording / reproducing by dividing a field into n tracks, a simple operation for a user can be realized in which a frame can be advanced by one field by pressing a frame advance button once. An object of the present invention is to provide a digital recording / reproducing apparatus.

[0011]

SUMMARY OF THE INVENTION The present invention relates to a digital recording / reproducing apparatus which performs recording / reproducing while dividing m fields into n tracks, when performing frame forward reproduction.
It has a bus that tells the servo circuit that controls the capstan motor that the data on the tape has been stored for one field in the memory of the signal processing circuit, and sends a signal from the signal processing circuit to the servo circuit via the bus. A digital recording / reproducing apparatus characterized by controlling the operation of the digital recording / reproducing apparatus.

[0012]

According to the present invention, m frames are converted to n
In a digital recording / reproducing apparatus which performs recording / reproducing by dividing into tracks, a simple operation is performed for a user, in which a single press of a frame forwarding button enables frame forwarding by one field.

[0013]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Note that, in the configuration diagram of the embodiment, the description of the blocks with the same numbers as those of the conventional example is omitted.

FIG. 1 is a diagram showing the configuration of a digital recording / reproducing apparatus according to one embodiment of the present invention. In FIG. 1, 10
1 is a servo circuit 4 for controlling the motor from the signal processing circuit 1
Reference numeral 102 denotes a frame forwarding button for notifying that one field of data has been stored in the memory 2 for storing data.

FIG. 2 is a diagram showing the movement of the capstan 7 and the flow of data from the magnetic tape 8 to the memory 2 in the digital recording / reproducing apparatus according to one embodiment of the present invention. In FIG. 2, (C) is a signal on the bus 101 that notifies the servo circuit 4 that controls the motor from the signal processing circuit 1 that data of one field has been stored in the memory 2.

In FIG. 1, when the user operates the various mode changeover switches 10 from the normal reproduction state and performs an operation to enter the operation mode of the temporary stop, the system controller 3 receives the operation of the changeover switches 10 and the operation between the respective blocks is performed. The capstan 7 is transmitted to the signal processing circuit 1 and the servo circuit 4 that controls the motor using the communication bus 9 so that the capstan 7 is set to the temporary stop operation mode. Capstan 7
Is in the operation mode of the temporary stop, the system controller 3 enters the operation mode in which frame advance can be performed. When confirming that the operation mode is the operation mode in which frame advance can be performed, the user presses the frame advance button 102 of the various mode changeover switch 10. Upon receiving a signal from the changeover switch 10, the system controller 3 uses the communication bus 9 between the blocks to notify the servo circuit 4 to rotate the capstan 7 at a low speed, and to the signal processing circuit 1 Tell them to send. While the capstan 7 is rotating at a low speed, the rotating head 6 continues to pick up data on the magnetic tape 8. However, since the capstan 7 is rotating at a lower speed than the normal reproduction, the trajectory of the rotating head 6 and the magnetic tape 8 is not normal, and the scanning of the rotating head 6 is performed over a plurality of tracks on the magnetic tape 8. In each track, data can be picked up little by little . Scan like this
Multiple times to accumulate the data amount for one field.
One screen by transferring data to memory until
can do.

The data on the magnetic tape 8 picked up by the rotary head 6 is sent to the signal processing circuit 1, from which the data is transferred to the memory 2 for storing the data. Then, data is stored in the memory 2 little by little, and when one field of data is stored in the memory 2, it is output as one screen for the first time. At the same time as the output timing, the bus 101 for transmitting the fact that data for one field has been stored in the memory 2 from the signal processing circuit 1 to the servo circuit 4 for controlling the motor. Sends a signal to tell that it has been stored. The servo circuit 4 stops the capstan 7 based on the signal on the bus 101. Also,
The signal processing circuit 1 continues to store the data on the magnetic tape 8 picked up by the rotary head 6 in the memory 2 until the capstan 7 stops after sending the signal on the bus 101. This is because a time lag occurs during the time when the capstan 7 is stopped after the signal is transmitted on the bus 101, so that the magnetic tape advances to the next field. This is to prevent data loss during the next frame advance.

Here, despite the fact that m frames are divided into n tracks, one field of data is output because when one frame of data is stored and output, two screens are output on the screen. This is a measure to prevent the user from feeling uncomfortable when considered as a frame advance operation.

The above operation is performed by the frame advance button 102
However, the present invention can be similarly realized by the JOG dial 11. In this case, it is specified that the feed is performed by one field by turning the JOG dial 11 at a certain angle, and the system controller 3 determines how many fields should be advanced from the rotation angle of the JOG dial 11 and determines each field. Using a communication bus 9 between blocks, the servo circuit 4 informs the servo circuit 4 how many fields to send, and the servo circuit 4 informs the signal processing circuit 1 that the memory 2 has stored data for one field. It is only necessary to judge how many times this signal should be sent to stop the capstan 7.

[0020]

As described above, according to the present invention, m
In a digital recording / reproducing apparatus which performs recording / reproducing by dividing a frame into n tracks, a dedicated bus is provided for transmitting to a servo circuit for controlling a capstan that data of one field is stored in a memory of a signal processing circuit. This makes it possible to control the frame advance, and its practical effect is great.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a digital recording / reproducing apparatus according to an embodiment of the present invention.

FIG. 2 is a timing chart showing the movement of the capstan and the flow of data from the magnetic tape to the memory in the digital recording / reproducing apparatus according to one embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a conventional digital recording / reproducing apparatus.

FIG. 4 is a schematic diagram showing a state in which a rotary head scans on a magnetic tape during slow playback in a conventional example.

FIG. 5 is a timing chart showing the movement of a capstan and the flow of data from a magnetic tape to a memory in a conventional digital recording / reproducing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Signal processing circuit 2 Memory 3 System controller 4 Servo circuit 5 Cylinder 6 Rotating head 7 Capstan 8 Magnetic tape 9 Bus 10 Changeover switch 11 JOG dial 12 JOG dial operation permission button 101 Bus 102 Frame feed button

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-258217 (JP, A) JP-A-6-30379 (JP, A) JP-A-62-121387 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) H04N 5/782-5/783 H04N 5/91-5/956 G11B 15/467

Claims (1)

(57) [Claims] 1. A helical scan type digital recording / reproducing apparatus for recording / reproducing digital data obtained by digitizing a video signal and an audio signal on a recording track inclined in a longitudinal direction on a magnetic tape by a rotary head. , M-frame data is divided into n tracks and recorded, and when the data is played back frame by frame , the data on the tape is stored in the memory of the signal processing circuit for one field , and The processing circuit is configured to store one file stored in the memory.
Field data and one field data
The has a bus to tell that it has Outputs from the memory to the servo circuit for controlling the capstan motor, the digital recording and reproducing apparatus and controls stopping the capstan by sending a signal in the bus.