KR0117998Y1 - Sound signal control apparatus - Google Patents

Abstract

The present invention is a voice signal control apparatus for variable speed reproduction of a VTR that can listen to a normal speed audio signal even at a variable speed reproduction of a video tape in a video tape recorder or a camcorder. An amplification unit for amplifying and outputting a voice signal applied from a voice signal converter, and a serial / parallel port for receiving parallel signals from a microcomputer to a controller for validating a synchronous signal, serial data, and an input signal. And, by receiving parallel data from the serial and parallel port, the audio signal applied from the amplifying unit is skipped and extended according to each shift mode and output to the amplifying unit, and the audio signal is stored in the memory for a predetermined time according to the shift mode and then read. The voice signal converter and the voice signal output from the voice signal converter for a predetermined time It consists of a memory to store.

Therefore, the present invention can listen to the forward voice signal at a normal speed even at the time of high speed playback or reverse high speed playback of the video tape, and can repeatedly listen to the voice signal at the moment of stopping even when the picture is stopped.

Description

[Designation name]

Audio signal control device for variable speed reproduction of video tape recorder

[Brief Description of Drawings]

1 is a block diagram showing an embodiment of an audio signal control apparatus for variable-speed reproduction of a VTR according to the present invention;

2 is a waveform diagram for explaining the operation of the device of FIG.

[Explanation of symbols on the main parts of the drawings]

10: amplification unit 20: voice signal conversion unit

22: control unit 24: A / D conversion unit

26: expander 28: D / A conversion unit

30: memory 40: serial port

50: micom

[Detailed Description of Design]

The present invention relates to a playback device of a video tape recorder (hereinafter referred to as a VTR) or a camcorder (CAMCORDER). In particular, the present invention provides a normal speed audio signal even at variable speed playback such as playing a video tape at high speed or freezing a picture. The present invention relates to an audio signal control apparatus for variable-speed reproduction of audible VTRs.

In conventional VTRs and camcorders, the audio signal is reproduced as fast as the speed of video tape when performing a high speed search or a variable speed playback function such as a still image. Therefore, in the existing VTR, the viewer was required to watch only the silent screen by canceling the audio signal during variable speed playback.

Therefore, the present invention skips the compressed audio signal at a high rate and outputs it by skipping it at a predetermined rate so that the user can listen to the audio signal at a normal speed while watching at high speed. It is an object of the present invention to provide an audio signal control apparatus for variable-speed reproduction of a VTR that repeatedly outputs an audio signal and outputs a forward audio signal at a normal speed using a memory even in reverse high-speed reproduction.

In order to achieve the above object, the present invention is a variable speed reproducing apparatus of a VTR for reproducing a voice signal of a normal speed by receiving a voice signal of a VTR that is reproduced at a high speed, after receiving and amplifying a compressed voice signal and then a voice signal. An amplifying unit for amplifying and outputting a voice signal applied from the voice signal converting unit, and a serial / parallel outputting parallel data to the controller by receiving a signal validating a synchronous signal, serial data, and an input signal from a microcomputer; It receives parallel data from the port and the serial and parallel port, skips and expands the audio signal applied from the amplifier according to each shift mode, and outputs the audio signal to the amplifier according to the shift mode. Memo for storing the voice signal converted from the voice signal converter and the voice signal converter for a predetermined time In that it comprises the features.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram showing an embodiment of an audio signal control apparatus for variable-speed reproduction of a VTR according to the present invention. First, the amplifier 10 receives an input audio signal AUDIO 1 and amplifies the audio signal converter. 20), the serial / parallel port 40 receives the strobe signal STROBE, the clock CLK, and the serial data DATA from the microcomputer 50, and processes the data into parallel data Q ₁ to Q ₈ for voice. When the signal is sent to the signal converter 20, the voice signal converter 20 skips the voice signal at a predetermined ratio and temporarily outputs the output of the amplifier 10 to the memory 30 according to the parallel data Q ₁ to Q ₈ . After storing and expanding, the output audio signal AUDIO 2 is output through the amplifier 10 again. The voice signal converter 20 skips the voice signal output from the amplifier 10 according to the variable speed control mode included in the parallel data Q ₁ to Q ₈ received from the serial / parallel port 40. The control unit 22 which sends to the D conversion unit 24 and applies the control signal CTR to the expander 26, and receives the skipped audio signal from the control unit 22, converts the digital signal into a memory 30 and the expander. The A / D converter 24 outputs to the 26 and the audio signal output from the A / D converter 24 for a predetermined period during the screen freezing operation or in the case of fast playback in the reverse direction. In response to the memory 30 outputted from the memory 30 and the control signal CTR of the control unit 22, the compressed audio signal is received from the A / D converter 24 to be decompressed at a predetermined stretch ratio and converted to D / A at high speed. The audio signal is read from the memory 30 in the case of outputting to the unit 28 and performing high speed playback in the reverse direction or in the reverse direction. And a D / A converter 28 for converting the voice signal of normal speed output from the expander 26 into an analog signal and outputting it to the amplification unit 10. It is composed of

FIG. 2 is a waveform diagram showing the operation of the audio signal reproducing apparatus at the variable speed reproduction of the VTR according to the present invention when the VTR is reproduced at twice the speed. FIG. The second (b) is a waveform representing the audio signal compressed in half as the tape is reproduced at high speed when reproduced at double speed.

Operation of the present invention configured as described above will be described in more detail with reference to FIG.

The compressed voice signal AUDIO 1 (waveform shown in FIG. 2 (b)) is supplied to the amplifying unit 10, amplified, and then input to the control unit 22. At this time, the microcomputer 50 connects the serial and parallel ports 40 to each other. When the serial signal DATA and the strobe signal STROBE for validating the clock signal CLK and the serial data DATA are applied to the serial / parallel port 40, the serial parallel port ( 40 processes data of the input serial data DATA into 8 bits BIT of parallel data Q ₁ to Q ₈ , and outputs the data to the controller 22 to inform the shift regeneration mode, and the controller 22 accordingly. It operates in the corresponding shift control mode. The controller 22 takes only one, two waveforms, and five or six waveforms based on a predetermined time ratio according to the shift mode of the audio signal (waveform shown in Fig. 2 (b)) output from the amplifier 10, and the three and four waveforms. And 8 and 8 waveforms are skipped (shown in FIG. 2 (C)), and are output to the A / D converter 24, while the stretcher 26 controls the stretch ratio according to the shift mode. Output (CTR). During high-speed playback, the A / D converter 24 digitally converts the skipped audio signal (waveform in FIG. 2 (C)) output from the controller 22 and sends it to the expander 26, and the expander 26 The digital signal of the digital signal (waveform shown in FIG. 2 (d)) as described above is extended to the expansion ratio (double speed) according to each double speed according to the control signal CTR of the control unit 22, and the D / A conversion unit ( 28), and the expanded audio signal (waveform in FIG. 2) is converted into analog signal (waveform in FIG. 2) at the same speed as the audio signal at normal speed by the D / A converter 28. Is converted. Finally, the amplifier 10 receives an analog output and amplifies and outputs it.

As described above, the time ratio of skipping the voice signal of the controller 22 and the voice signal extension ratio of the expander 26 are converted according to each double speed reproduction, so that an audio signal of normal speed can be obtained even at high speed reproduction.

In the case of high speed playback in the reverse direction, since the voice signal played back in the reverse direction must be changed in the forward direction, the control unit 22 operates as described above, and the A / D conversion unit 24 applies the digital signal to the memory 30. After a predetermined time, the decompressor 26 reads the audio signals in order from the memory 30 in accordance with the control signal of the controller 22, decompresses them at a predetermined decompression ratio, and outputs them to the D / A converter 28. Subsequent operations also operate in the same manner as in high speed playback.

Therefore, even in the case of high-speed playback in the reverse direction, the voice signal is temporarily stored in the memory 30 and then the voice signal is sequentially output from the memory in a predetermined time unit in the expander 26 according to the control signal CTR of the controller 22. It reads out and expands and outputs, so a forward voice signal at normal speed can be obtained.

In addition, when the screen stop operation is performed, the control unit 22 receives the parallel data Q ₁ to Q ₈ from the serial / parallel port 40 to enter the screen stop control mode, and the A / D conversion unit 24 displays the screen. The voice signal at the stopped moment is digitally converted and stored in the memory 30, and the expander 26 continues to freeze from the memory 30 while the control signal CTR applied from the controller 22 is applied. The audio signal is received and output to the D / A converter 28. Other operations are the same as in the case of high speed playback.

Therefore, even when the screen is stopped, the audio signal of the moment when the screen is stopped is repeatedly output.

As described above, the audio signal control apparatus at the variable speed reproduction of the VTR according to the present invention skips the compressed audio signal at a predetermined ratio during high speed reproduction and expands it at an extension ratio according to a specified double speed to obtain a normal speed audio signal. In the case of reverse high speed playback using the memory, you can get the normal speed forward audio signal, and even when the screen is stopped, the voice signal at the moment the screen is stopped is stored in the memory and the audio signal is repeatedly output. It is effective to listen to the audio signal of.

Claims (3)

A variable speed reproducing apparatus for a VTR for receiving a voice signal of a VTR that is reproduced at high speed and includes a micom to reproduce a voice signal at a normal speed; Amplifying means for receiving and amplifying the compressed speech signal and outputting the amplified speech signal to the speech signal converting means and amplifying and outputting the speech signal applied from the speech signal converting means; A serial-parallel port configured to receive a synchronization signal, a signal for validating serial data and an input signal from the microcomputer, and output parallel data to a control unit; After receiving parallel data from the serial-parallel port, the audio signal applied from the amplifying means is skipped and extended according to each shift mode and outputted to the amplifying means, and the voice signal is stored in the memory for a predetermined time according to the shift mode. Audio signal converting means for reading; And a memory for storing the voice signal outputted from the voice signal converting means for a predetermined time. The apparatus of claim 1, wherein the speech signal converting means skips the compressed speech signal received from the amplifying means at a predetermined rate and applies it to the A / D converting means according to the parallel data input of the serial / parallel port. The control unit for applying a control signal containing the stretch ratio according to the variable speed mode; An A / D converter which receives the skipped voice signal from the controller, converts the digital signal into a digital signal, and outputs the converted digital signal to the memory and the expander; An expander which receives a voice signal from the A / D converter or the memory according to a control signal of the controller, expands the voice signal at a predetermined stretch ratio, and outputs the voice signal to a D / A converter; And a D / A converter which receives a voice signal extended at a normal speed from the expander and converts the voice signal into an analog signal and outputs the analog signal to the amplifying means. 3. The apparatus of claim 2, wherein the decompressor receives and decompresses an audio signal from an A / D converter during high speed reproduction, and outputs the audio signal. In reverse high speed reproduction, reverse audio data is received from the memory in a predetermined time unit. And an audio signal at the time of variable speed reproduction of the videotape recorder, wherein the audio signal is read out repeatedly from the memory when the screen is stopped.