KR0175833B1 - Variable speed reproducing method for voice signal by servo speed control - Google Patents

Abstract

The present invention relates to a voice signal variable speed reproduction method by servo speed control. When a voice signal recorded on a recording medium is to be reproduced at a slow speed of 1x or less, the audio signal is output in response to the reproduction time of the video signal. In order to prevent the audio signal from being partially lost, a voice signal variable speed reproduction method of slowly changing and reproducing a voice signal recorded on a recording medium by less than 1x speed: a voice signal at a rotational speed of a motor for transferring a recording medium. The speed was reduced to match the speed of the regeneration.

Description

Voice signal variable speed reproduction method by servo speed control

1 is a view showing an embodiment of a conventional audio signal shift reproduction method.

2 is a view showing another embodiment of the conventional audio signal shift reproduction method.

FIG. 3 is a diagram showing an audio signal shifted and reproduced at 1 / 2x speed and a video signal during normal playback according to the audio signal shift playback method shown in FIG.

4 is a schematic block diagram for performing a voice signal shift reproduction method according to the servo speed control according to the present invention.

5 is a view showing a video signal and an audio signal modulated by the present invention.

* Explanation of symbols for main parts of the drawings

1: Analog-to-Digital Converter 2: Memory

3: audio signal shift processing unit 4: microcomputer

5: Digital / Analog Converter 6: Variable Resistance

7: motor

The present invention relates to a method for reproducing an audio signal by servo speed control, and more particularly, in a video and audio signal variable speed reproducing apparatus for shifting and reproducing video and audio signals recorded on a recording medium. The present invention relates to a variable speed reproduction method of an audio signal by servo speed control to prevent loss of an audio signal by synchronizing and reproduced an audio signal shifted and reproduced at a speed.

In general, in the case of changing the reproducibility of the video and audio signals recorded on the recording medium, if the speed is rapidly reproduced, the reproduced audio signal is sounded like a 'beeping sound' from the height of the original sound. Slow playback speeds usually sound like a 'tapping tape'.

In order to prevent such a phenomenon from occurring, conventionally, a method of temporarily storing a voice signal in a memory and reproducing only a part of the stored voice signal has been used. That is, conventionally, a method of storing a voice signal in a memory and reproducing only one of two time-slices when the reproduction speed is doubled.

Therefore, when the 'I go to school with Young-hee' is reproduced at a double speed according to the conventional method, as shown in FIG. 1, the voice of the patterned part of the original sound is dropped, and the voice signal of 'I go together' is output. .

As described above, the conventional method does not preserve the meaning of the original audio signal because only a part of the audio signal is reproduced to maintain the tone when the reproduction speed is increased. Therefore, in the case of shifting and reproducing a voice signal using the voice signal variable speed reproducing apparatus, it is difficult to understand the meaning of voice, and there is a problem of making the listener feel rejected.

In order to solve the above problems, the present applicant has proposed a 'voice signal variable speed reproduction apparatus' (Patent Application No. 94-24514 (September 28, 1994). According to FIG. 2, the random unvoiced sound, which is characteristic of the voice signal, is not modulated, but by partially deleting or copying and adding regularly repeated voiced sound to change the length of the voice signal. Since this principle is described in detail in the 'voice signal variable speed reproduction apparatus' presented by the present applicant, a separate description thereof will be omitted, and the core part applied to the present invention will be described in detail later.

However, in the case described above, when the video and audio signals recorded on the recording medium are shifted and reproduced at 1/2 the speed, the video signals are reproduced at the normal speed while the audio signals are expanded twice as much as the original length. In order to synchronize the video signal and the audio signal, half of the audio signal shifted and reproduced at 1/2 times had to be removed.

As a result, as shown in FIG. 3, since the variable speed reproduced voice signal is reproduced by 1/2, there is a problem that the original meaning of the voice signal is not preserved and lost.

Accordingly, an object of the present invention is to solve the above-described problem, and an object of the present invention is to change the speed of reproduction of the audio signal to synchronize the video signal with the shifted reproduction audio signal when the audio signal is slowly reproduced at 1 times or less. The present invention provides a method for regenerating an audio signal by servo speed control to control a servo speed correspondingly.

A feature of the present invention for achieving the above object is a voice signal variable speed reproduction method of slowly changing and reproducing an audio signal recorded on a recording medium by less than 1x speed: a rotational speed of a motor for transporting a recording medium. The present invention provides a method for shifting and reproducing an audio signal by servo speed control, which reduces and reproduces the audio signal to match the shifting and reproducing speed.

In the present invention, the speed change reproduction speed processed by the voice signal shift processing unit is detected; It is preferable to output a control signal corresponding to the detected speed change reproduction speed so as to control the rotation speed of the motor so that the length of the speed change reproduced audio signal coincides with the length of the video signal having a variable reproduction speed.

Best Mode for Carrying Out the Invention Preferred embodiments of the voice signal variable speed reproduction method according to the servo speed control according to the present invention will now be described in detail with reference to the accompanying drawings.

4 is a schematic block diagram for performing a voice signal shift reproduction method according to the servo speed control according to the present invention.

Referring to FIG. 4, the analog / digital converter 1 and the analog / digital converter 1 convert analog voice signals detected from a recording medium (not shown) into digital voice signals. The memory 2 temporarily stores the digital signal in order to process the voice signal, and the voice signal shifting process is performed through the shift regeneration process as shown in FIG. 2 by detecting the voice signal stored in the memory 2. In the processing unit 3, the microcomputer 4 which outputs a control signal for controlling the shift processing operation of the audio signal shift processing unit 3 according to the shift control signal applied from the outside, and the sound signal shift processing unit 3 It consists of a digital-to-analog converter 5 for converting a shifted sound signal of a shifted digital form into a shifted sound signal of an analog form.

In addition, the variable resistor 6 receives a control signal from the microcomputer 4 and varies the current value detected from a predetermined voltage applied from a constant voltage source (not shown). It consists of a motor 7 which receives a current value and controls the conveying speed of the recording medium (not shown).

However, the motor 7 described above corresponds to a capstan motor when the recording medium is a magnetic recording medium such as a video tape, and a spindle motor when the recording medium is an optical recording medium such as a compact disc.

The operation of the present invention having the configuration as described above will be described in detail with reference to FIG.

If the user selects 1 / 2x playback to watch the video and audio signals recorded on the recording medium at a slow speed, this shift control signal is applied to the microcomputer 4. At this time, the microcomputer 4 outputs a control signal to the voice signal shift processing section 3 to set the speed change reproduction speed of the voice signal shift processing section 4 to 1/2 times.

When the setting process is completed, the analog audio signal detected from the recording medium (not shown) is converted into the digital audio signal through the analog-to-digital converter 1, and then the audio signal shift processing unit 3 is turned on. Are stored in the memory (2).

Thereafter, the voice signal shift processor 3 detects a predetermined amount of the voice signal stored in the memory 2, and duplicates the voiced sound portion that is regularly repeated without copying the unvoiced portion of the detected voice signal. Synthesize voiced and crude voices. Therefore, the voice signal shifted by 1/2 times has a length twice that of the original audio signal. The shifted sound signal of the digital form thus shifted is converted into the shifted sound signal of analog form through the digital / analog converter 5 and finally output.

On the other hand, the microcomputer 4 changes the resistance value of the variable resistor 6 in accordance with the shift reproduction speed of the shift control signal input from the outside. Accordingly, a variable current is applied to the motor 7 by the predetermined voltage and the variable resistance value, thereby changing the rotation speed of the motor 7. For example, when the microcomputer 4 doubles the resistance value of the variable resistor 6, a predetermined voltage having a fixed voltage value is applied to the variable resistor 6, and eventually the motor 7 is in a steady state. Since the current is supplied 1/2 times as compared, the motor 7 rotates slowly 1/2 times as compared to the normal speed. As the motor 7 is rotated slowly by 1/2 times, the feed speed of the recording medium is decelerated by 1/2 times, and the reproduction time of the video signal is also doubled.

Therefore, since the video signal reproduced at 1/2 times and the audio signal modulated at 1/2 times are output in synchronization with each other, the audio signal is not lost even when shifting reproduction at 1/2 times. The meaning of can be preserved.

As described above, according to the method of reproducing the voice signal by the servo speed control according to the present invention, in the case of reproducing the voice signal recorded on the recording medium slower than 1 times, the speed of the motor for feeding the recording medium is controlled by the voice signal. By slowing down and replaying the video so that the video signal and the audio signal are synchronized with each other and outputting it in synchronization with each other, the original meaning of the audio signal can be preserved because the audio signal is not lost even when the playback is slower than 1x. There is this.

On the other hand, in the present invention, since the video signal and the audio signal are synchronously outputted by the same process as in the case of 1 / 2x speed in the case of slow shift playback of 1x or less, the same applies to all cases of slow playback at 1x or less. Reveal.

Claims (1)

A voice signal variable speed reproduction method for slowly reproducing a voice signal recorded on a recording medium at a speed lower than N times, and detecting a predetermined amount of a voice signal stored in a memory, and the voiced sound portion of the detected voice signal that is regularly repeated by the user. A first step of synthesizing the crude voice with a multiple of N times the selected reproduction speed and outputting the synthesized audio signal to a digital / analog converter; And increasing the value of the variable resistor connected to the motor according to the variable speed reproduction speed selected by the user in the first step to reduce the amount of current supplied to the motor to reduce the transfer speed of the recording medium. A voice signal variable speed reproduction method according to the servo speed control, characterized in that made.