JPH04247303A - Audio signal reproducing device - Google Patents

Abstract

PURPOSE:To preferentially output different sounds, such as after-recording audio signals, when such sounds are recorded in the video and-audio recording and reproducing device having plural audio recording and reproducing channels. CONSTITUTION:The audio signals are reproduced by each channel by an audio reproducing means 13 and a high-fidelity audio level which is the main sound is detected by a level detecting means 6. The high-fidelity sounds and the sounds of other channels are compared by a level comparator 12 to detect the identity of the signals. A switch control circuit 7 inputs the result of the level detection and the result of the identity detection and selects and outputs the afterrecording sounds, mixed sounds, etc., in priority sequence preset by the combinations of the detection results.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an audio signal reproducing apparatus in a video/audio recording/reproducing apparatus having a plurality of audio recording/reproducing channels, such as a VHS (registered trademark) high-fidelity video tape recorder.

0002

[Prior Art] In recent years, video tape recorders (hereinafter referred to as V
(referred to as TR) has become popular, and the ways to enjoy it are diversifying, one of which is editing audio recordings.

Conventionally, there are two types of audio signal recording and reproducing methods, for example, in VHS high-fidelity VTRs: linear audio, in which a fixed head records on tracks parallel to the running direction of the magnetic tape; There are two channels of high-fidelity audio recorded on diagonal tracks.

[0004]Although the sound quality of linear audio is relatively poor, since it can be re-recorded independently of the video signal, it is possible to record only the audio after editing the video (after-recording, hereinafter referred to as dubbing). be. on the other hand,
As the name suggests, high-fidelity audio has relatively good sound quality, and because it records FM-modulated signals with a rotating head, there is little deterioration in sound quality in long-term recording mode, and it has recently been widely used as the main audio channel. Ru.

[0005] In such a VHS high-fidelity VTR,
Normally, during recording, both channels record the same audio in conjunction with video input. Furthermore, some models allow recording of an audio signal unrelated to the video input on the high-fidelity audio side (hereinafter referred to as simultaneous recording).

Hereinafter, the reproduction operation of the conventional audio signal recording and reproduction apparatus will be explained with reference to the drawings. FIG. 2 shows a block diagram of the configuration of an audio signal reproducing device in a conventional video/audio recording/reproducing device. In the figure, a reproduced signal obtained by a fixed head 1 is amplified and frequency characteristic corrected by a first signal processing circuit 2 and output as a first audio signal. On the other hand, the reproduced FM signal obtained by the rotary head 3 is amplified to a predetermined level by the amplifier circuit 4, and then sent to the second signal processing circuit 5.
is output to the level detector 6. Second signal processing circuit 5
performs predetermined signal processing such as FM demodulation and frequency correction on the input reproduced FM signal and outputs a second audio signal. The level detection circuit 6 detects whether the reproduced FM signal is at a predetermined level or higher, and outputs the result to the switch control circuit 7. The first and second audio signal outputs are input to a mixer 8 and a switch 9, respectively. The switch control circuit 7 controls the switch circuit 7 based on the output of the level detection circuit 6 and information from the manual selection input 10, and selects the audio signal to be output. This automatic selection gives priority to high-fidelity audio, so if the reproduced FM signal is above a predetermined level, the second
The audio signal (high-fidelity audio signal) is selected and output, and if the level is less than a predetermined level, the first audio signal (linear audio) is set to be output. In addition, in the selection operation using the manual selection input 10, the first audio (high-fidelity audio), the second audio (linear audio), and the audio that is a mixture of both can be arbitrarily selected at any time. Used to insert background music and narration.

[0007]

[Problem to be Solved by the Invention] In such a conventional audio signal playback device, when a magnetic tape that has been dubbed is played back, if the audio is recorded in high fidelity during video and audio recording, the automatic audio selection will not produce high fidelity audio. There is a problem that priority is given to the audio of dubbing recording (linear audio) is not output. Of course, the audio of the dubbing recording can be output using the manual selection input 10, but if high-fidelity recording and linear dubbing recording are mixed on one magnetic tape, it is necessary to switch manually each time, or If you don't like the switching operation, you will have to endure continuous playback of linear audio with poor sound quality.

[0008] The present invention solves the above-mentioned problem, and when a magnetic tape on which dubbing recording (linear audio) has been applied to high-fidelity audio recording (FM recording) is played back, the reproduced audio of the dubbing recording is automatically output. It is an object of the present invention to provide an audio signal reproducing device that can set priority means for output audio.

[0009]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides an audio reproducing means having a plurality of audio signal recording and reproducing channels and reproducing an audio signal for each of the audio channels; A mixing device for mixing audio signals, a switching device for selecting and outputting one of the plurality of reproduced audio signals and mixed audio signals, and a level detection device for detecting a signal level of a specific channel. In the video/audio recording and reproducing apparatus, an identity determining means detects the sameness of audio by comparing the reproduced audio signal of the specific channel and the reproduced audio signal of other channels;
The audio signal reproducing device includes switch control means for controlling the switch means to select and output audio signals in a priority order set based on a combination of the output of the level detection means and the output of the identity determination means. .

0010

[Operation] In the above structure, the level detection means detects the signal level of a specific channel, the identity determination means determines the identity of the audio signal of the specific channel and the audio signal of another channel, and the switch control means controls the switch means to select the audio signal in accordance with the priority set by the combination of the results of the level detection means and the identity determination means.

[0011]

Embodiments (Embodiment 1) Hereinafter, an audio signal reproducing apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a block diagram of the configuration of an audio signal reproducing apparatus according to an embodiment of the present invention. In the figure, a first signal processing circuit 2 amplifies and corrects the frequency characteristics of a reproduced signal obtained by a fixed head 1 and outputs a first audio signal, and an amplifier 4 outputs a reproduced FM signal obtained by a rotating head 3. amplify to a predetermined level,
The second signal processing circuit 5 performs predetermined signal processing such as FM demodulation and frequency correction on the output, and outputs a second audio signal. The level detection circuit 6 detects whether the reproduced FM signal is at a predetermined level or higher, and outputs the result to the switch control circuit 7. The first and second audio signal outputs are input to a mixer 8, a switch 9, and a level comparator 12, respectively. The functions and operations of the above components are the same as those of the conventional example.

In the present invention, a new component is the level comparator 12, and the switch control circuit 7 also has a different function from that of the conventional example. The level comparator 12 detects the difference in amplitude between the first and second audio signals, detects whether the difference is greater than or equal to a predetermined value, and detects the sameness of the signals, and uses the result to control the switch. Output to circuit 7. Further, the switch control circuit 7 is controlled by the detection result of the level detection circuit 6, the identity determination result of the level comparison circuit 12, and information from the manual selection input 10, and selects the audio signal and outputs it to the output terminal 11.

The operation of the above configuration will be explained below. In the switch control circuit 7, first, the level detector 6
When it is detected that the reproduced FM signal is at a predetermined level or higher, the comparison result of the level comparator 12 is referred to. That is, when the difference between the amplitudes of the first audio signal and the second audio signal is less than a predetermined value as a result of comparing the amplitudes of the first audio signal and the second audio signal with the level comparator 12, it is determined that the first and second audio signals are the same audio signal. Then, the second audio signal (high-fidelity audio) is set to be selected and output with priority. Furthermore, when the amplitude difference between the first and second audio signals is greater than or equal to a predetermined value, it is determined that the signals are different from each other (it is determined that the signals have been recorded after dubbing), and the first audio signal (linear audio ) is output to the output terminal 11 with further priority over the second audio (high-fidelity audio).

Next, when the level detector 6 detects that the reproduced FM signal is below a predetermined level, the first audio (linear audio) is outputted to the output terminal 11 with priority.

Of course, it is also possible to arbitrarily select and output the first, second, or mixed audio by manual selection.

Note that when it is desired to make use of the original FM sound during dubbing, priority may be set so that the output of the mixer 8 is automatically selected.

As described above, the audio reproducing apparatus according to the embodiment of the present invention includes a level comparison circuit that compares the amplitudes of the first audio signal and the second audio signal to detect the sameness of the signals; The system includes a level detection circuit for detecting the level of the FM signal, and a switch control circuit for selecting an output signal based on the results of the level comparison means and the level detection means, and outputs the audio signal of the priority set based on the combination of the detection results. By using an audio playback device that outputs, even in the case of a magnetic tape recorded with FM (high-fidelity audio recording), the audio of dubbing recording can be automatically output, eliminating the trouble of manual switching selection.

Note that even if the signals are the same, the level comparing means cannot make a determination based on the amplitude difference when the reproduced signal levels are different, but it can determine the identity by detecting the phase difference.

[0019]

As is clear from the above embodiments, the present invention has a plurality of audio signal recording and reproducing channels, an audio reproducing means for reproducing an audio signal for each of the audio channels, and an audio reproducing means for reproducing the audio signal for each of the audio channels. A video/audio device comprising a mixing means for mixing, a switch means for selecting and outputting one of the plurality of reproduced audio signals and mixed audio signals, and a level detecting means for detecting a signal level of a specific channel. In the recording and reproducing apparatus, an identity determining means for detecting the sameness of voices by comparing the reproduced audio signal of the specific channel and the reproduced audio signal of another channel, and the output of the level detecting means and the identity determining means. The audio signal reproducing apparatus is equipped with a switch control means for controlling the switch means to select and output audio signals in accordance with a priority set by a combination of outputs. A desired audio signal is outputted from among them in a set priority order, and therefore, even in the case of a magnetic tape recorded with FM (high-fidelity audio recording), the audio of the dubbing recording can be prioritized and automatically output.
Eliminates the hassle of manual switching selection.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an audio signal reproducing device according to an embodiment of the present invention.

[Fig. 2] Block diagram showing the configuration of a conventional audio signal reproducing device

[Explanation of symbols]

6 Level detection circuit (level detection means) 7
Switch control circuit (switch control means) 8 Mixing circuit (mixing means) 9 Switch circuit (switch means) 10 Manual selection input 11 Audio signal output terminal 12 Level comparison circuit (identity determination means) 13 Audio reproduction means

Claims (1)

[Claims] 1. Audio reproducing means having a plurality of audio signal recording and reproducing channels, reproducing an audio signal for each of the audio channels, mixing means for mixing the reproduced audio signals, the plurality of reproduced audio signals and In a video/audio recording and reproducing apparatus comprising a switch means for selecting and outputting one of the mixed audio signals, and a level detecting means for detecting the signal level of a specific channel, the reproduced audio signal of the specific channel and an identity determining means for detecting the sameness of the audio by comparing the reproduced audio signals of other channels; and an audio signal in a priority order set by a combination of the output of the level detecting means and the output of the identity determining means. An audio signal reproducing device comprising switch control means for controlling the switch means to selectively output.