JP2906812B2 - 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.

[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, one frame or one field of data is not recorded on one track, but m fields or m frames of data are recorded on n tracks and reproduced. Therefore, the control of the capstan, in which the data on the magnetic tape is transmitted one frame or one field at a time during special playback of slow and still, is performed by using a JOG dial or the like that can freely control the speed of the capstan. The magnetic tape is fed little by little by running the tape at a low speed, and during that time, a plurality of tracks on the magnetic tape are scanned many times by a magnetic head, and each time the data of the plurality of tracks obtained from the magnetic head is processed by a signal processing circuit. And a picture is output when one frame or one field of data is stored in the memory.

FIG. 5 is a diagram showing a configuration of a conventional digital recording / reproducing apparatus. In FIG. 5, 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 signal line for communication between blocks, reference numeral 10 denotes a switch for selecting various modes, reference numeral 11 denotes a JOG dial for freely controlling the speed of the capstan, and reference numeral 12 denotes a JOG dial operation permission button.

FIG. 6 shows a rotary head 6 during slow reproduction.
FIG. 3 is a diagram showing a state in which scanning is performed on the magnetic tape 8. Here, the description is made on the assumption that the number of tracks in one frame is five. In FIG. 6, reference numeral 21 denotes the trajectory of the head for normal reproduction, and reference numeral 22 denotes the trajectory of the head at the time of slow motion.

FIG. 7 is a timing chart showing the movement of the capstan 7 and the flow of data from the magnetic tape 8 to the memory 2. In FIG. 7, 31 indicates a change in the speed of the capstan, 32 indicates the amount of data in the memory 2,
33 is the amount of data for one frame or one field, and 34 is the timing at which data for one frame or one field is accumulated.

[0006] From the normal playback state, the user operates the JOG dial operation permission button 1 of the various mode changeover switch 10.
In step 2, an operation is performed to enter the mode in which the JOG dial 11 can be operated. The system controller 3 accepts the operation of the JOG dial operation permission button 12 of the changeover switch 10, stops the capstan 7 for the servo circuit 4 that controls the motor using the signal line 9 for communication between each block, and stops the JOG dial. Tell them to be in operation mode. When the capstan 7 is in the JOG dial operation mode, the system controller 3 sends the JOG dial 1
Put 1 in a mode where you can actually operate it. User is JO
When it is confirmed that the mode has become a mode in which the G dial 11 can be actually operated, the JOG dial 11 is operated. JOG
Upon receiving the signal from the dial 11, the system controller 3 uses the signal line 9 for communication between the blocks to notify the servo circuit 4 to rotate the capstan 7 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 trajectory of the rotary head 6 and the magnetic tape 8 is not normal. Also, the state that data can be picked up only partially for each track continues. The data on the magnetic tape 8 picked up by the rotating head 6 is sent to the signal processing circuit 1, and the data is transferred therefrom to the memory 2 for storing the data. Then, the data is stored in the memory 2 little by little, and is output as one screen only when data for one frame or one field is stored in the memory 2. Until then, the user operates the JOG dial 11 little by little while watching the output screen until the output screen is switched. When the user confirms that the output screen has been switched, the throw of one frame or one field is completed, and the user sets the JOG dial 1
If it is necessary to stop the operation of 1 or advance one frame or one field, operate the JOG dial again in the same manner.

[0007]

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

In the prior art, slow and still operations are
Since control circuits such as a servo and a system controller operate independently of the signal processing circuit, the only control means of the capstan motor is a method for the operator to determine by looking at the output screen, that is, a JOG dial or the like. However, a simple operation for the user, for example, one frame or one field can be advanced by pressing the frame advance button once, has not been realized.

The present invention has been made in view of the problems of the prior art, and
Provided is a digital recording / reproducing apparatus for recording / reproducing by dividing a frame into n tracks, wherein a signal processing circuit and a servo circuit are synchronized to control a capstan. The purpose is to do.

[0010]

SUMMARY OF THE INVENTION The present invention relates to a digital recording / reproducing apparatus which performs recording / reproducing while dividing m frames into n tracks, when performing slow / still reproduction, the deceleration timing of the capstan and signal processing. A signal line for synchronizing the circuit switching and a signal line for transmitting to the servo circuit for controlling the capstan motor that the data on the tape has been stored for one frame or one field in the memory of the signal processing circuit. It is a digital recording / reproducing apparatus characterized by having.

[0011]

According to the present invention, m frames are converted to n
In a digital recording / reproducing apparatus which performs recording / reproducing in tracks, by using two signal lines, the processing signal circuit and the servo circuit are synchronized, the capstan is controlled, and slow / still reproduction is performed. In addition, simple slow and still control that is separated from the user's hand becomes possible with a circuit.

[0012]

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.

(First Embodiment) FIG. 1 is a diagram showing a configuration of a digital recording / reproducing apparatus according to a first embodiment of the present invention.
In FIG. 1, reference numeral 100 denotes a servo circuit 4 for controlling a motor.
A signal line for transmitting the transition from the normal reproduction mode to the slow still mode from the signal processing circuit 1 to the signal processing circuit 101. Data for one frame is stored in the memory 2 for storing data from the signal processing circuit 1 to the servo circuit 4 for controlling the motor. This is a signal line that informs the user of the event.

FIG. 2 shows a signal processing circuit 1 and a capstan 7 in a digital recording / reproducing apparatus according to a first embodiment of the present invention.
5 is a timing chart showing the movement of data and the flow of data from the magnetic tape 8 to the memory 2. In FIG. 2, 11
0 is a signal from the servo circuit 4 for controlling the motor to the signal processing circuit 1
A signal on a signal line 100 indicating that the mode has shifted from the normal reproduction mode to the slow still mode, and a signal 111 indicating that one frame of data has been stored in the memory from the signal processing circuit 1 to the servo circuit 4 for controlling the motor. Line 101
Is an operation mode in the signal processing circuit.

From the normal reproduction state, the user operates the various mode changeover switch 10 to perform an operation to enter the still or slow operation mode. The system controller 3 receives the operation of the changeover switch 10 and uses the signal line 9 for communication between the blocks to inform the servo circuit 4 for controlling the motor that the capstan 7 is in the still or slow operation mode. . The servo circuit 4 sends a signal to the signal processing circuit 1 via the mode transition signal line 100, and the signal processing circuit 1 switches from the normal reproduction mode to the slow and still reproduction mode. The servo circuit 4 reduces the speed of the capstan 7 in synchronization with the output of the signal line 100. While the capstan 7 is rotating at a low speed, the rotating head 6 continues to pick up data on the magnetic tape 8. But,
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 spans a plurality of tracks on the magnetic tape 8, and For each track, data can be picked up little by little. The data on the magnetic tape 8 picked up by the rotating head 6 is sent to the signal processing circuit 1, and the data is transferred therefrom to the memory 2 for storing the data. Then, data is stored in the memory 2 little by little, and when one frame of data is stored in the memory 2, it is output as one screen for the first time. At the same time, the servo circuit 4 for controlling the motor from the signal processing circuit 1
To the servo circuit 4 via a signal line 101 for notifying that data of one frame has been stored in the memory 2
A signal indicating that data for a frame has been stored is sent. The servo circuit 4 stops the capstan 7 if the still operation is performed by the signal on the signal line 101. In addition, the signal processing circuit 1 transmits the signal on the signal line 101 and keeps the magnetic tape 8 picked up by the rotary head 6 until the capstan 7 stops.
The above data is kept stored in the memory 2. This is signal line 1
Since the time lag necessarily occurs between the time when the signal is transmitted at 01 and the capstan 7 stops, the magnetic tape advances to the next frame. When that happens,
This is to prevent data from being lost when performing the next slow or still operation. During the slow operation, the servo circuit 4 ignores the signal from the signal line 101.

The above operation can also be realized by the JOG dial 11 without the slow and still operations. At that time, it is specified that the tape is sent for one frame by turning the JOG dial 11 at a certain angle.
The system controller 3 determines how many frames should be advanced from the rotation angle of the JOG dial 11 and uses the communication signal line 9 between the blocks to inform the servo circuit 4 how many frames to send. Is the number of times the signal on the signal line 101 for transmitting that one frame of data is stored in the memory 2 from the signal processing circuit 1
Is to be stopped.

(Embodiment 2) FIG. 3 is a diagram showing the configuration of a digital recording / reproducing apparatus according to a second embodiment of the present invention.
In FIG. 3, reference numeral 201 denotes a signal line for transmitting that one field of data is stored in the memory 2 for storing data from the signal processing circuit 1 to the servo circuit 4 for controlling the motor.

FIG. 4 shows a signal processing circuit 1 and a capstan 7 in a digital recording / reproducing apparatus according to a second embodiment of the present invention.
5 is a timing chart showing the movement of data and the flow of data from the magnetic tape 8 to the memory 2. In FIG.
1 is a servo circuit 4 for controlling the motor from the signal processing circuit 1
Is a signal on the signal line 201 that indicates that data for one field has been stored in the memory.

From the normal reproduction state, the user operates the various mode changeover switch 10 to perform an operation to enter the still or slow operation mode. The system controller 3 accepts the operation of the changeover switch 10, and uses the signal line 9 for communication between the respective blocks so that the servo circuit 4 that controls the motor operates the capstan 7 in the still or slow operation mode. Tell The servo circuit 4 sends a signal to the signal processing circuit 1 via the mode transition signal line 100, and the signal processing circuit 1 switches from the normal reproduction mode to the slow and still reproduction mode. The servo circuit 4 reduces the speed of the capstan 7 in synchronization with the output of the signal line 100. While the capstan 7 is rotating at a low speed, the rotating head 6 continues to pick up data on the magnetic tape 8. But,
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 spans a plurality of tracks on the magnetic tape 8, and For each track, data can be picked up little by little. The data on the magnetic tape 8 picked up by the rotating head 6 is sent to the signal processing circuit 1, and the data is transferred therefrom 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, a signal line 201 for transmitting from the signal processing circuit 1 to the servo circuit 4 for controlling the motor that the data of one field has been stored in the memory 2 is transmitted to the servo circuit 4 by the signal line 201
A signal indicating that data for one field has been stored. The servo circuit 4 stops the capstan 7 if the still operation is performed based on the signal on the signal line 201. Further, 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 the signal is sent on the signal line 201. This is because a time lag occurs inevitably between the time when the capstan 7 stops after the signal is transmitted on the signal line 201, and the magnetic tape advances to the next field. This is to prevent data from being lost when the next throw or still is performed. During the slow operation, the servo circuit 4 ignores the signal from the signal 101.

The above operation can also be realized by the JOG dial 11 without being limited to the slow and still operations. At that time, it is prescribed that the tape is to be fed 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, Using the communication signal line 9 between the 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 data for one field has been stored in the memory 2. It is determined how many times the signal on the signal line 201 occurs to stop the capstan 7.

[0021]

As described above, according to the present invention, m
In a digital recording / reproducing apparatus in which a frame is divided into n tracks for recording / reproducing, a signal line for synchronizing a deceleration timing of a capstan and a circuit switching of signal processing, and a memory for a signal processing circuit for one frame, or By providing two signal lines for transmitting the stored data for one field to the servo circuit for controlling the capstan, simple slow and still control can be performed with a simple circuit without the operator's hand. Its practical effect is great.

[Brief description of the drawings]

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

FIG. 2 is a timing chart in the digital recording / reproducing apparatus according to the first embodiment of the present invention.

FIG. 3 is a schematic diagram showing a configuration of a digital recording / reproducing apparatus according to a second embodiment of the present invention.

FIG. 4 is a timing chart in a digital recording / reproducing apparatus according to a second embodiment of the present invention.

FIG. 5 is a schematic diagram showing a configuration of a conventional digital recording / reproducing apparatus.

FIG. 6 is a schematic diagram showing a state in which a rotary head scans on a magnetic tape during conventional slow reproduction.

FIG. 7 is a timing chart 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, 100, 101, 201 Signal line 10 Various mode changeover switches 11 JOG dial 12 JOG dial operation permission button

────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Atsushi Hashimoto 1006 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (58) Field surveyed (Int.Cl. ⁶ , DB name) G11B 15/467

Claims (2)

(57) [Claims] 1. Digital data obtained by digitizing a video signal and an audio signal are divided into n frames of data on a recording track inclined in a longitudinal direction on a magnetic tape into n tracks, and signals are recorded and reproduced by a rotary head. A helical scan type digital recording / reproducing apparatus,
When performing slow / still reproduction, a signal line for transmitting the transition from normal reproduction to slow / still mode from the servo circuit to the signal processing circuit and data on the tape are stored in the memory of the signal processing circuit for one frame or more. A digital recording / reproducing apparatus having a signal line for transmitting the information to the servo circuit for controlling a capstan motor. 2. Digital data obtained by digitizing a video signal and an audio signal are divided into n tracks on a recording track inclined in a longitudinal direction on a magnetic tape into n tracks, and signals are recorded and reproduced by a rotary head. A helical scan type digital recording / reproducing apparatus,
When performing slow / still reproduction, a signal line for transmitting the transition from normal reproduction to slow / still mode from the servo circuit to the signal processing circuit and data on the tape are stored in the memory of the signal processing circuit for at least one field. A digital recording / reproducing apparatus having a signal line for transmitting the information to the servo circuit for controlling a capstan motor.