JP3232746B2 - Video / audio signal reproducing method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for reproducing a video / audio signal applied to, for example, a MUSE video disk player or a VTR.

[0002]

2. Description of the Related Art For example, in a MUSE type video disk player or VTR, a MUSE type video / audio signal is reproduced as it is and supplied to a subsequent MUSE decoder or MUSE-NTSC converter to be supplied to a receiver. I try to get an audio signal. In this case, since the MUSE decoder and the MUSE-NTSC converter are designed on the assumption of the MUSE video / audio signal by broadcasting, the MUSE video / audio signal reproduced from the video disk player or VTR as described above is used. It has been found that when supplied, various disadvantages occur.

That is, for example, in a video disc player or VTR, there is a so-called variable speed playback mode in addition to the normal mode playback. There is. On the other hand, the MUSE video / audio signal is configured as shown in FIG. 6, and the audio signal provided in one video field is 348 samples × 40 lines + 270
Sample × 4 lines = 15,000 samples. On the other hand, the audio signal is digitized and
As shown in (1), 1350 bits (binary) = 900 samples (ternary) (1 sample = 1 / 12.15 MHz) is formed as one audio frame. Therefore MUSE
The audio signal in one video field of the video / audio signal of the system does not contain a sample of an integral multiple of an audio frame as a unit.

[0004] For this reason, in the MUSE video / audio signals arranged in a different order from the original as described above, the data of the digitized audio signal becomes discontinuous, and this signal is converted to a MUSE decoder or a MUSE-NTSC converter. And demodulates the analog signal, extremely unpleasant noise is generated. Alternatively, the speaker may be damaged by a large level of noise. In a video disc player or a VTR, such a state in which the data of the audio signal is discontinuous is caused by switching from the normal playback mode to the stop mode in addition to the above-described variable speed playback mode.
Alternatively, it may occur when switching from the normal reproduction mode to the fast forward or rewind mode without video reproduction.

[0005] By the way, in order to prevent the same noise as described above from occurring in the MUSE video / audio signal when the signal source is switched or the relay line is switched in the broadcasting station, the MUSE decoder or the MUSE decoder is used. -NTSC
2. Description of the Related Art A control signal for suppressing output of an audio signal from a converter has been added. That is, such a control signal corresponds to the control code 2 provided in the above-described voice frame.
It is provided at the 16th bit of the 2 bits. When this bit is “1”, the output of the audio signal is suppressed.

However, currently available MUSE decoders and MUSE-NTSC converters require two steps from the detection of a control signal to the actual suppression of the output of an audio signal.
00 to 300 msec. There is about a time delay. On the other hand, in a broadcasting station, the timing of adding the control signal is advanced in advance so that the output of the audio signal is suppressed at the time when noise occurs regardless of the time delay. That is, such a specification was sufficient for a design assuming a video and audio signal of the MUSE system by broadcasting. However, it is difficult for a video disc player or a VTR to know in advance the time at which the mode is switched, and even if a control signal is added, noise may be generated before the output of the audio signal is suppressed.

On the other hand, in a MUSE video disk player or VTR which has been conventionally researched and developed, when an MUSE audio signal is interrupted due to variable speed reproduction or the like, 300 msec. During this period, the normal reproduction is continued, and during this period, a control signal for suppressing the output of the audio signal is added, and 300 msec. The variable speed reproduction is performed later. When a picture stop code is provided on the recording medium, 300 ms after detecting the stop code
ec. During this period, the normal reproduction is continued. During this period, a control signal for suppressing the output of the audio signal is added, and then the reproduction position is returned to the stop code detection position to set the still image mode. When performing variable speed reproduction using a memory, the audio signal is 300 msec. During this period, the normal reproduction is continued, a control signal for suppressing the output is added to the audio signal, and the audio signal is synthesized with the video signal from the memory and output. And so on.

The picture stop code is
For reproducing a predetermined image as a still image, for example, provided in a control address signal multiplexed on the 19th to 474th samples of the 564th signal line of the MUSE video / audio signal in a video disk player. . The 564th signal line is provided with a program transmission control signal and the like in broadcasting. That is, this control address signal is transmitted with six samples of the MUSE signal as one bit, and provided with a 76-bit code as shown in FIG. And 49th to 68th of them
1st of FADR2 code provided in 20th bit
The bit is a picture stop code. For example, when this bit is “1”, the still image mode is requested.
This picture stop code is provided consecutively, for example, in three of the frames required for the still image mode.

However, in the above method, as shown in FIG. 9, a time difference occurs between the operation of the button and the operation such as variable speed reproduction. In the method described above, as shown in FIG. 10, a different image ahead of the image to be stopped is seen. In the method (1), as shown in FIG. 11, the video signal of the memory and the reproduced audio signal must be synthesized, which causes a problem in synchronization and the like. And so on. The present application has been made in view of such a point.

[0010]

The problem to be solved is to reproduce a recording medium in which a digitized audio signal is sequentially inserted into a video signal in a unit different from the unit of the video signal and recorded. In the method and apparatus for reproducing a video / audio signal, when the video / audio signal reproduced in the normal mode is switched to a different mode, the audio suppression processing cannot be performed well.

[0011]

A first means according to the present invention is to reproduce a recording medium in which a digitized audio signal is sequentially inserted into a video signal in a unit different from the unit of the video signal and recorded. In the method of reproducing the video and audio signals,
When the video / audio signal being reproduced in the normal mode is switched to a different mode, the video signal is repeatedly reproduced in units of a common multiple (3 frames) of the audio signal unit and the video signal unit. This is a video / audio signal reproducing method in which audio suppression processing is performed during a certain period (300 msec.).

A second means according to the present invention is a method of reproducing a video / audio signal for reproducing a recording medium in which a digitized audio signal is sequentially inserted into a video signal in a unit different from the unit of the video signal. In the device, when the video / audio signal being reproduced in the normal mode is switched to a different mode, the audio signal in the video / audio signal is stored in units of a common multiple of the unit of the audio signal and the unit of the video signal. Memory (3-frame memory 22 for audio signal)
Is provided, and the memory 22 is repeatedly read out, and the audio / video signal reproducing apparatus performs the audio suppression processing (the generators 10, 12, and the selector 13) during the period in which the repeated reading is performed.

According to a third aspect of the present invention, there is provided a video / audio apparatus which performs the processing according to the first or second means when the video / audio signal reproduced in the normal mode is switched to the variable speed reproduction mode. A signal reproducing method or device.

According to a fourth aspect of the present invention, there is provided a video / audio signal which performs the processing according to the first or second means when the video / audio signal being reproduced in the normal mode is switched to a stop mode. Of the present invention.

According to a fifth aspect of the present invention, when the video / audio signal reproduced in the normal mode is switched to a fast forward or rewind mode without video reproduction,
A video / audio signal reproducing method or apparatus for performing the processing described in the first or second means.

[0016]

According to this, the time difference between the operation of the button and the operation such as variable speed reproduction, the problem of seeing a different image ahead of the image to be frozen, and the problem of synchronization with the video signal of the memory are solved. It is possible to satisfactorily solve the problem and perform the voice suppression processing satisfactorily.

[0017]

FIG. 1 shows an example of a configuration in which the present invention is applied to a video disk player. In this figure, 1
Is a video disk. For example, an MUSE video / audio signal recorded on the disk 1 is reproduced by the optical pickup 2 and supplied to the FM demodulator 3. The signal from the FM demodulator 3 is transmitted through the A / D converter 4 to T
It is supplied to the BC memory 5.

The signal from the FM demodulator 3 is supplied to a control address signal detection circuit 6, and a control address signal superimposed on the MUSE signal 564th signal line is detected. The detected control address signal is used as a control microcomputer (μ-
COM) 7 to perform control using, for example, a picture stop code. Further, a signal from the key switch 8 is supplied to the microcomputer 7 to control, for example, a still image and a variable speed reproduction by a manual operation of the user.

A signal from the microcomputer 7 is supplied to a tracking and focusing servo circuit 9, and a signal from the servo circuit 9 is supplied to the optical pickup 2 to perform arbitrary tracking and focusing servo. A signal from the microcomputer 7 is supplied to a timing generator 10, and a signal from the timing generator 10 is stored in a memory 5 for TBC.
And the time axis of the reproduction signal is corrected. The signal from the TBC memory 5 is supplied to the D / A converter 11.

Further, a signal from the timing generator 10 is supplied to a voice suppression bit generator 12, and the signal from the voice suppression bit generator 12 and the D / A converter 11
Is supplied to the selector 13. Further, the switching of the selector 12 is performed by a signal from the timing generator 10, and the selected signal is taken out to the output terminal 14.

In this device, the audio signal provided in one video field is 15000 samples as described above. In contrast, one audio frame is 900 samples. Here, when the least common multiple of 15000 and 900 is obtained, the value is 45000, which corresponds to three video fields. Therefore, the continuity of the audio frame is maintained in units of three video fields. However, since video signals are generally easy to handle in frame units, it is assumed that continuity of audio frames is maintained in three video frame units (six video field units).

In the above-described apparatus, when the still image mode is controlled by the key switch 8, for example, a -3 track jump (-3T
A control signal for performing the tracking servo of J) is supplied to the servo circuit 9. As a result, three video frames are repeatedly reproduced as shown in FIG. 2, and the continuity of the audio frames is maintained. In this state, an audio suppression bit is generated from the generator 12, and the selector 12 is switched to set the 16th bit of the control code 22 bits provided in the audio frame to "1".

Further, this state is set to 300 msec. Maintain for a while. And 300 msec. Elapses, the microcomputer 7 makes a -2 track jump (-2TJ)
Is supplied to the servo circuit 9. As a result, in the reproduction, two video frames are repeatedly reproduced, and a still image is reproduced. Also in this state, the audio suppression bit is generated from the generator 12, and the selector 12 is switched to set the 16th bit of the control code 22 bits provided in the audio frame to "1". In this state, the audio signal may be replaced with so-called gray level (intermediate level) data.

That is, in this reproducing method, when the video / audio signal being reproduced in the normal mode is switched to a different mode, the reproduction is repeatedly performed in units of a common multiple (3 frames) of the unit of the audio signal and the unit of the video signal, The period during which this repetitive reproduction is performed (300 mse
c. ) To perform voice suppression processing.

Therefore, in this method, the subsequent MUSE
There is a possibility that there is a time delay from the detection of the control signal by the decoder or the MUSE-NTSC converter to the actual suppression of the output of the audio signal. During this period, the continuity of the audio frame is maintained, and the possibility of extremely unpleasant noise due to discontinuity of the audio signal data and the possibility of the speaker being damaged by large-level noise is eliminated. Note that this operation is not limited to the above-described still image reproduction, and may be performed when switching from a general variable-speed reproduction mode, a normal reproduction mode to a stop mode, or switching from a normal reproduction mode to a fast-forward or rewind mode without video reproduction. Has the same effect.

According to the above-mentioned reproducing method (apparatus), problems such as the time difference between the operation of the button and the operation such as the variable-speed reproduction, and the fact that an image different from the image to be frozen can be seen are satisfactorily solved. Thus, the audio suppression processing can be performed favorably.

In the above-mentioned reproducing method (apparatus),
For example, when a picture stop code is provided on a video disc, reproduction is performed as shown in FIG. In the figure, a video signal provided with such a picture stop code is recorded in units of six frames, and the picture stop code is provided in the latter three frames. Then, when two picture stop codes are detected in the video disc player, the same still image reproduction as described above is performed.

That is, in the above-described device, the control address signal is detected by the detection circuit 6, and the detected control address signal is supplied to the control microcomputer (μ-COM) 7. When the picture stop code in the control address signal is determined, the microcomputer 7 supplies a control signal for performing tracking servo of -3 track jump (-3TJ) to the servo circuit 9. As a result, three video frames are repeatedly reproduced, and at this time, continuity of the audio frames is maintained. Further, in this state, a sound suppression bit is generated from the generator 12 and the selector 12
To control code 2 provided in the audio frame.
The 16th bit of the two bits is set to “1”.

Further, this state is set to 300 msec. For 300 msec. Is passed, the microcomputer 7 supplies a control signal for performing tracking servo of -2 track jump (-2TJ) to the servo circuit 9. As a result, in the reproduction, two video frames are repeatedly reproduced, and a still image is reproduced. Also in this state, the audio suppression bit is generated from the generator 12, and the selector 12 is switched to set the 16th bit of the control code 22 bits provided in the audio frame to "1".

That is, also in this case, when the video / audio signal reproduced in the normal mode is switched to a different mode, the reproduction is repeatedly performed in units of the audio signal unit and the common multiple (3 frames) of the video signal unit. Period during which this repetitive reproduction is performed (300 msec.)
Perform voice suppression processing. Therefore, in this method, there is a possibility that there is a time delay from the detection of the control signal by the MUSE decoder or the MUSE-NTSC converter at the subsequent stage to the actual suppression of the output of the audio signal for 200 to 300 ms.
ec. During this period, the continuity of the audio frame is maintained, and the possibility of extremely unpleasant noise due to discontinuity of the audio signal data and the possibility of the speaker being damaged by large-level noise is eliminated.

Further, in the above description, the case of VTR or CAV video discs capable of variable speed reproduction by track jump has been described. For example, variable speed reproduction using an image memory is carried out for a CLV video disk. Have been. In this case, when the present invention is applied, it can be performed using, for example, an apparatus as shown in FIG.

That is, in the figure, the signal from the TBC memory 5 is supplied to the video signal two-frame memory 21 and the audio signal three-frame memory 22, and from the memories 21, 22, and the TBC memory 5, Is supplied to the selector 23. The timing generator 10
Is supplied to the memories 21 and 22 to control writing and reading. Further, the selector 23
Is controlled by a signal from the timing generator 10, and the selected signal is supplied to the D / A converter 11. Other configurations are the same as those in FIG.

In this apparatus, in the normal reproduction mode, the selector 23 is controlled so as to select a signal from the TBC memory 5, and the memories 21 and 22 store two video frames of the video signal and the audio signal respectively. Are sequentially updated and written. Therefore, for example, when control of the still image mode is performed by the key switch 8, the memories 21 and 22 are transmitted from the microcomputer 7.
Is supplied to the timing generation circuit 10.

As a result, as shown in FIG. 5, the reproduction of the video signal is performed, for example, in the fourth mode in which the control of the still image mode is performed.
Two video frames of the fifth frame are repeatedly read from the memory 21, and a still image is reproduced. On the other hand, in the reproduction of the audio signal, for example, three video frames of the third, fourth, and fifth frames are repeatedly read from the memory 22, and at this time, the continuity of the audio frame is maintained. Then, these signals are selected by the selector 23 and supplied to the D / A converter 11.

That is, in this case, the timing of reading signals from the memories 21 and 22 can be arbitrarily determined, and there is no problem in synchronization or the like. The figure shows a state where an audio signal is selectively inserted for each field of a video signal. And this D / A
In response to the signal from the converter 11, the generator 12 generates a speech suppression bit, and switches the selector 12 so that the 16th bit in the control code 22 bits provided in the speech frame is output.
The bit is set to “1”.

Therefore, in this method, the subsequent MUSE
There is a possibility that there is a time delay from the detection of the control signal by the decoder or the MUSE-NTSC converter to the actual suppression of the output of the audio signal. During this period, the continuity of the audio frame is maintained, and the possibility of extremely unpleasant noise due to discontinuity of the audio signal data and the possibility of the speaker being damaged by large-level noise is eliminated. Note that this operation is not limited to the above-described still image reproduction, and may be performed when switching from a general variable-speed reproduction mode, a normal reproduction mode to a stop mode, or switching from a normal reproduction mode to a fast-forward or rewind mode without video reproduction. Has the same effect.

According to this reproducing method (apparatus),
Speech suppression is achieved by satisfactorily resolving the time difference between button operation and operations such as variable speed playback, the problem of seeing a different image ahead of the image to be frozen, or the problem of synchronizing with the video signal in memory. The processing can be performed favorably.

Further, this state is, for example, 300 msec.
For 300 msec. After the time elapses, the audio signal may be replaced with so-called gray level (intermediate level) data together with the generation of the audio suppression bit. This can also prevent the occurrence of noise or the like when returning to the normal reproduction mode after variable-speed reproduction or the like. Further, this playback method (apparatus) can be applied not only to playback of a CLV video disc, but also to playback of a VTR or CAV video disc.

The above-described reproducing method (apparatus) can also be applied when returning to the normal reproducing mode after variable-speed reproduction or the like. Thus, even when the audio signal is not replaced with so-called gray level (intermediate level) data as described above, it is possible to prevent the occurrence of noise or the like when returning to the normal playback mode after variable speed playback or the like. can do.

[0040]

According to the present invention, the time difference between the operation of the button and the operation such as the variable speed reproduction, the problem that an image different from the image to be stopped is seen, the synchronization with the video signal of the memory, etc. Has been successfully solved, and the voice suppression processing can be performed satisfactorily.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an example of a video / audio signal reproducing apparatus according to the present invention.

FIG. 2 is a diagram for explaining this.

FIG. 3 is a diagram for explaining this.

FIG. 4 is a configuration diagram of another example of a video / audio signal reproducing apparatus according to the present invention.

FIG. 5 is a diagram for explaining this.

FIG. 6 is a diagram for explaining a video and audio signal of the MUSE system.

FIG. 7 is a diagram for explaining an audio signal.

FIG. 8 is a diagram for explaining a control address signal.

FIG. 9 is an explanatory diagram of a problem in a case where an audio signal is interrupted in variable speed reproduction or the like.

FIG. 10 is an explanatory diagram of a problem in a case where a still image mode is set by detecting a stop code.

FIG. 11 is an explanatory diagram of a problem when performing variable speed reproduction using a memory.

[Explanation of symbols]

 Reference Signs List 1 video disk 2 optical pickup 3 FM demodulator 4 A / D converter 5 memory for TBC 6 detection circuit for control address signal 7 microcomputer for control (μ-COM) 8 key switch 9 servo circuit for tracking and focusing Reference Signs List 10 timing generator 11 D / A converter 12 audio suppression bit generator 13, 23 selector 14 output terminal 21 2 frame memory for video signal 22 3 frame memory for audio signal

Claims (5)

(57) [Claims] 1. A video / audio signal reproducing method for reproducing a recording medium in which a digitized audio signal is sequentially inserted into a video signal in a unit different from a unit of the video signal, and reproduced in a normal mode. When switching the video / audio signal to a different mode, the audio / video signal is repeatedly played back in units of a common multiple of the audio signal unit and the video signal unit, and the audio suppression processing is performed during the period of the repeated playback. Method of reproducing video and audio signals. 2. A video / audio signal reproducing apparatus for reproducing a recording medium in which a digitized audio signal is sequentially inserted into a video signal in a unit different from a unit of the video signal, and is reproduced in a normal mode. A memory for storing the audio signal in the video / audio signal in units of a common multiple of the audio signal unit and the video signal unit when the video / audio signal is switched to a different mode; A video / audio signal reproducing apparatus that performs repeated reading and performs audio suppression processing during a period in which the repeated reading is performed. 3. A method or apparatus for reproducing a video and audio signal, wherein the processing according to claim 1 or 2 is performed when the video and audio signal reproduced in the normal mode is switched to a variable reproduction mode. 4. The method according to claim 1, wherein said video / audio signal being reproduced in said normal mode is switched to a stop mode.
Or a reproduction method or apparatus for a video / audio signal, which performs the processing described in 2. 5. A video / audio signal which is to be processed according to claim 1 or 2 when said video / audio signal being reproduced in said normal mode is switched to a fast forward or rewind mode without video reproduction. Reproduction method or device.