JP2956150B2 - Playback signal format converter - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television broadcasting system different from a television broadcasting system in which a reproduced video signal reproduced from a recording medium in which a television broadcasting video signal is recorded is recorded. This is related to a reproduction signal system for converting to a reproduction signal.

2. Description of the Related Art FIG. 3 is a block diagram showing a system converter of a conventional magnetic recording and reproducing apparatus. A system control circuit 1 for controlling a mode transition, a conversion source command circuit 2 for commanding a converted television broadcasting system (hereinafter simply referred to as a broadcasting system), and a conversion destination command circuit 3 for commanding a broadcasting system to be converted; A reproducing signal processing circuit 8 for performing a reproducing operation according to the selected broadcasting method, a recording processing circuit 7 for performing a recording operation according to the selected broadcasting method, a servo circuit 9 for outputting a reproduced image, and a converting operation of the broadcasting method. A system conversion circuit 6 for performing conversion; a system determination circuit 4 for determining inputs from the conversion source command circuit 2 and the conversion destination command circuit 3 in accordance with a mode and outputting the signals to the reproduction signal processing circuit 8 and the recording processing circuit 7; The system includes a system discriminating circuit 5 that discriminates inputs from the source command circuit 2 and the conversion destination command circuit 3 according to the mode and outputs the signals to the system conversion circuit 6.

Regarding the magnetic recording / reproducing device configured as described above,
In the following, the operation is performed using the SECAM
The case where the playback mode is the NTSC system and the conversion destination system is the PAL system will be described with reference to the timing chart of FIG.

FIG. 4A shows a recording system screen which is sent from the system control circuit 1 of FIG. 3 to the system discrimination circuit 4 of FIG. 3 to display a recording system screen at H level and a reproduction system screen at L level. FIGS. 4B and 4C show a system switching signal of a system screen, and FIG. 4B and FIG. 4C show a system determination signal (hereinafter referred to as a recording / reproducing system) sent from the system determination circuit 4 of FIG. 3 to the recording processing circuit 7 and the reproduction signal processing circuit 8 of FIG. Signal B is at H level in the NTSC system (hereinafter signal B is referred to as NTSC signal), and signal C is at H level at PA
L and D (hereinafter, the signal C is referred to as a recording / reproducing PAL signal). FIGS. 4D and 4E show the converted system signals (from the system discriminating circuit 5 shown in FIG. 3) to the system converting circuit 6 shown in FIG. In the following, the signal D is at H level in the SECAM system (hereinafter, the signal D is referred to as the conversion source SECAM signal), and the signal D is H level.
Represents the NTSC system at the H level (the signal E is hereinafter referred to as a source NTSC signal). Here, the recording system screen is a state in which the magnetic recording / reproducing apparatus is outputting the output video signal through the color television system conversion circuit without passing the input video signal through the electromagnetic conversion system when the recording operation or the stop state is performed. The reproduction system screen means a state in which a reproduced video signal from a recording medium is output through a color television system conversion circuit when the magnetic recording / reproducing apparatus is in a reproducing state.

Therefore, in FIG. 3, the recording system screen input to the format conversion circuit 9 is an input video signal, and generates a screen projected on a connected monitor television (not shown) during a recording operation. The recording screen input to the format conversion circuit 9 is a recording video signal to be recorded on the recording system screen, that is, a recording medium obtained by converting the input video signal into a specific color television format. The playback screen input to the format conversion circuit 9 is a playback video signal played back from a recording medium, and the video output output from the format conversion circuit 9 is finalized according to the state of the magnetic recording and playback device. An output video signal output to the outside (monitor television).

Therefore, the screen switching signal between the recording system screen and the reproduction system screen is a recording system screen according to the operation state of the magnetic recording / reproducing apparatus, for example, a stop state or a reproduction state, a recording video signal including a system conversion, and a reproduction system screen or a system. This is a control signal for switching a reproduced video signal including conversion.

In this magnetic recording / reproducing apparatus, a stop state (hereinafter referred to as STOP
In this case, the recording system screen is input to the format conversion circuit shown in FIG. 6 and is converted by the format conversion circuit 6 into the broadcast format of the conversion destination signal given from the format determination circuit 5 and is output as a video output. Output. When performing a recording operation, the system conversion circuit 6 causes the recording processing circuit 7 in FIG.
The recording screen is output to the recording processing circuit 7 to perform a recording operation. At this time, the recording processing circuit 7 receives the recording destination system as the recording / reproducing system signal from the system identification circuit 4. This recording / reproducing method signal is output during the recording operation, but the recording destination method is output even in the stop state. That is, in the recording mode, the recording / reproducing signal is the same as the converted signal.

In the playback state, a playback screen is sent from the playback signal processing circuit of FIG. 3 to the format conversion circuit of FIG. 3, and the format of the broadcast signal of the conversion destination signal given by the format determination circuit of FIG. It is output as a video output converted by the conversion circuit.
At this time, since the reproduction signal processing circuit 8 has to perform the reproduction process in the conversion source broadcasting system, the conversion source system is sent from the system determination circuit 4 to the reproduction signal processing circuit 8 as a recording / reproducing system signal. That is, in the reproduction mode, the recording / reproducing signal is the same as the original signal.

In other words, in this magnetic recording / reproducing apparatus, a recording / reproducing signal is output in the same system as the conversion destination system when the recording system screen is displayed, and a signal in the same format as the conversion source system is output when the reproduction screen is displayed.

In FIG. 4, when the screen switching signal A is at the H level,
Since the conversion source signal is the SECAM system, the conversion source SECAM signal D is set to the H level, and the recording / reproducing signal is set to the H level because the recording screen is displayed and the conversion destination system is the PAL system. .

Next, the mode shifts to a normal playback mode (hereinafter referred to as a PLAY mode), and when the screen switching signal A changes to the L level, the conversion source system is the playback mode and the NTSC system, so the conversion source
The level of the SECAM signal D is switched to the L level. The source NTSC signal E is switched to the H level. The recording / reproducing signal is the NTSC system.
The TSC signal B is switched to the H8 level. By the above operation, the video recording processing circuit 7, the reproduction signal processing circuit 8, and the format conversion circuit 6 of FIG. 3 are controlled, and the output switching from the recording screen to the reproduction screen is performed.

However, in the above-described conventional configuration, the reproduction of the servo circuit for transmitting the broadcast method signal to the reproduction signal processing circuit at the same time as the conversion of the screen switching signal to output the reproduction screen is performed. There is a problem that the image output processing is delayed and an unstable image is output.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and has as its object to output a stable image when the mode shifts from the stop mode to the reproduction mode.

Means for Solving the Problems In order to solve the above problems, in the reproduction signal format conversion apparatus of the present invention, the switching of the system identification signal sent to the recording processing circuit and the reproduction signal processing circuit is switched from the stop mode to the reproduction system mode. At the time of starting the reproduction system operation, and switching the system identification signal sent to the reproduction signal processing circuit earlier than the screen switching.

Operation The present invention makes it possible to output a stable image when the mode is switched from the stop mode to the reproduction mode by the above configuration.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a system conversion peripheral portion in a magnetic recording / reproducing apparatus according to an embodiment of the present invention. The difference from the conventional example is that a mode discrimination signal is sent from a system control circuit 1 to a system discrimination circuit 4. However, the rest is the same as the conventional example, and thus the description is omitted.

Regarding the magnetic recording / reproducing device configured as described above,
The operation is described below with reference to the timing chart of FIG.
The case where the C method and the conversion destination method are the PAL method will be described.

In this magnetic recording / reproducing apparatus, when stopped, the recording system screen is input to the system conversion circuit shown in FIG. 1 and is converted by the system conversion circuit 6 into the broadcast system of the conversion destination signal given by the system determination circuit 5. Method conversion circuit 6
Output. When performing a recording operation, a recording screen is output from the system conversion circuit 6 to the recording processing circuit 7 in FIG. 1, and the recording operation is performed by the recording processing circuit 7. At this time, the video recording processing circuit 7 receives the video recording system from the system discrimination circuit 4 as a recording / reproducing system signal. This recording / reproducing method signal is output during the recording operation, but the recording destination method is output even in the stop state.
That is, in the recording mode, the recording / reproducing signal is the same as the conversion destination signal.

In the playback state, a playback screen is sent from the playback signal processing circuit of FIG. 8 to the format conversion circuit of FIG. 6, and the broadcast format of the conversion destination signal given by the format determination circuit of FIG. It is converted by the conversion circuit and output as a video output. At this time, since the reproduction signal processing circuit 8 has to perform the reproduction process in the conversion source broadcasting system, the conversion source system is sent from the system determination circuit 4 to the reproduction signal processing circuit 8 as a recording / reproducing system signal. That is, in the reproduction mode, the recording / reproducing signal is the same as the original signal.

In other words, in this magnetic recording / reproducing apparatus, a recording / reproducing signal is output in the same system as the conversion destination system when the recording system screen is displayed, and a signal in the same format as the conversion source system is output when the reproduction screen is displayed.

First, based on the information of the mode discrimination signal F, the source SECAM signal D is set to the H level because the conversion source system is the SECAM system in the STOP mode, and the recording / reproducing PAL signal B is set to the H level because the conversion destination system is the PAL system. Next, when the PLAY mode is entered and the PLAY mode signal is sent from the mode determination signal F, the start of the PLAY mode is known. The signal C is switched to the H level. As for the conversion source signal, when the screen switching signal A changes from the H level to the L level, the change source SECAM signal D is changed to the L level conversion source NTSC signal E as in the conventional example.
To the H level. Generally, when a magnetic recording / reproducing apparatus is shifted from a stop state (STOP mode) to a reproduction state (PLAY mode), a rotating magnetic head or a magnetic tape is driven,
Since a certain period of time is required until the head and the tape are pulled into the predetermined phase state, if the screens are switched at the same time, the reproduced video signal is disturbed until the servo circuit is pulled in, and the distorted video is displayed on the monitor television screen. Therefore, in the present invention, a mode discrimination signal is added to the system control circuit 1 in consideration of the time until the servo circuit pulls in, and furthermore, the output timing of the screen switching signal is delayed so that a disturbed image is not output.

The above description of the operation has been made when the conversion destination system is the PAL system, the conversion source system in the STOP mode is the SECAM system, and the conversion source system in the playback system mode is the NTSC system. The timing at which the signal changes is the same only by changing the name of the middle method, and the description of the operation is omitted.

In this embodiment, the operation in the PLAY mode has been described with respect to the reproduction system operation. However, not only the normal reproduction as in the PLAY mode but also the special reproduction such as fast forward reproduction, rewind reproduction, still image reproduction, etc. Are exactly the same.

From the playback system operation to the stop operation, the screen switching is slower than the mode switching at the time of rewind playback. At the time of switching, the recording / reproducing method signal is switched.

As described above, according to the present embodiment, when the mode is switched from the stop mode to the playback system mode, the output switching of the system identification signal to be sent to the recording processing circuit and the playback signal processing circuit is performed from the start of the playback system operation. A stable image can be output at the time of image output.

Effect of the Invention As described above, according to the present invention, when the mode is switched from the stop mode to the playback system mode, the output switching of the system identification signal to be sent to the recording processing circuit and the playback signal distance circuit is performed at the start of the playback system operation. An object of the present invention is to realize a magnetic recording / reproducing apparatus capable of outputting a stable image when outputting an image.

[Brief description of the drawings]

FIG. 1 is a block diagram of a system conversion peripheral portion in one embodiment of the present invention, FIG. 2 is a timing chart at the time of transition from a stop mode to a reproduction mode in one embodiment of the present invention, and FIG. Block diagram of system conversion peripheral part, 4th
FIG. 2 is a timing chart at the time of a mode transition from a conventional stop mode to a reproduction mode. 1... System control unit, 2... Conversion source command circuit, 3.
Conversion destination command circuit, 4... Method discrimination circuit, 5... Method discrimination circuit, 6... Method conversion circuit, 7.
... Reproduction method processing circuit, 9 ... Servo circuit.

Claims (1)

(57) [Claims] 1. A first reproduced video signal reproduced from a recording medium on which a video signal of a first television broadcasting system is recorded is converted into a second television broadcasting system different from the first television broadcasting system. A system control circuit for controlling the system of the playback signal format converter, a conversion source command circuit for specifying the first TV broadcast format, and a conversion for commanding the second TV broadcast format. A pre-instruction circuit, a reproduction signal processing circuit for reproducing a video signal from the recording medium, a recording processing circuit for recording an external video signal on the recording medium, and transmitting the reproduction signal or the recording signal to the second System conversion circuit for converting to a television broadcasting system, and a first system determination circuit to which a first control signal from the system control circuit and a command signal from the conversion source command circuit are input. The first type discrimination circuit output is input as a second control signal of the reproduction signal processing circuit, and a third control signal from the system control circuit and the conversion source command circuit and the conversion destination command circuit And a second type discriminating circuit that outputs a fourth control signal for controlling the type conversion circuit, wherein the second type discriminating circuit outputs a fourth control signal for controlling the type converting circuit. A reproduction signal format conversion apparatus characterized in that a good video signal is obtained from the format conversion circuit by changing output timings of a fourth control signal and the second control signal.