JP3455829B2 - Audio phase adjuster - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an audio phase adjusting device, and more particularly to an audio phase adjusting device for reproducing audio signals of a tape recorder of a broadcasting station.

[0002]

2. Description of the Related Art In a radio or television broadcasting station, it is most unavoidable that an abnormality occurs in a single device such as a VTR or a tape recorder used for transmitting a broadcast program and the transmission of the broadcast program is interrupted. That is something that must be done.
Therefore, it is usual to make the device redundant (simultaneous reproduction of two working / spare devices) in consideration of a device failure.

In the case of an audio tape recorder used in a radio broadcasting station, for example, if two tape recorders, an active / standby tape recorder, are started at the same time, the start time of the equipment varies, and the reproduced audio from the two tape recorders. It is unavoidable that a maximum time difference of about 500 ms occurs between programs. Therefore, if there is something wrong with the current tape recorder and the playback signal is switched from the current one to the backup tape recorder, the broadcast audio program will be interrupted (the sound is interrupted or the same sound is repeated) at the moment of switching.
Occurs.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to prevent a broadcast audio program from being disturbed (the sound being interrupted or the same sound being repeated) even when the tape recorder or the like is switched from the active system to the standby system. It is an object of the present invention to provide a voice phase adjusting device which is prevented from being generated.

[0005]

According to the present invention, there is provided an audio phase adjusting apparatus for an active / standby system of an audio broadcast program, which converts reproduced audio signals of the active system and the standby system into digital audio data of the active system and the standby system. Means, a start point detecting means for the digital audio data of the active system and the standby system, a time difference measuring means for measuring a time difference existing between start points of the digital audio data for the standby system and the active system, and the time difference measuring means. Audio data delaying means for delaying the standby system digital audio data by the output of the above.

[0006]

The operation of the present invention is as follows.
By starting the tape recorder of the standby system earlier than the active system, measuring the phase difference of the reproduced audio program between the standby system side and the active system side, and giving a delay corresponding to the phase difference to the standby system side, Match the phase of the reproduced audio program of the active system / standby system.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of an audio phase adjusting apparatus according to the present invention, FIG. 2 is a waveform diagram for explaining the start timing of a tape recorder of a working / standby system, and FIG. 3 is a reproduced voice. It is a waveform diagram explaining the phase difference measurement of a signal, and the same signal is shown by the same code.

In FIGS. 1 and 2, a control unit (control which is the main component of the audio phase adjusting device) is based on an audio device start control signal a from an automatic program control device (not shown) which controls the operation of the entire broadcast program. The computer 5 first starts a backup tape recorder or the like in response to the backup audio device # 2 start control signal b. At the same time, the delay time measurement counter 3 is reset. Then, with a delay of td (for example, 1 second), the active audio device # 1 start control signal c
Start a current tape recorder.

As shown in FIG. 3, an active tape recorder or the like (voice device # 2) which is delayed with respect to the reproduced audio signal h of the backup tape recorder or the like (audio device # 2).
The delay time of the reproduced voice signal g of 1) is measured by the counter 3 and the delay corresponding to the delay time is added to the reproduced voice signal h of the standby system to output the output voice of the active system and the standby system. The phases of the signals can be matched.

In FIG. 1, the reproduction audio signal g of the active system (audio device # 1) is transmitted (broadcast) as output audio through the switching SW8, and at the same time, analog / digital (A /
D) Converted into a digital audio signal by the converter 1 to become audio data # 1i. The reproduction system audio signal # 2 reproduced audio signal h is also converted into audio data # 2j by the A / D converter 2.

In general, a voice signal is converted into a digital signal having sign flag information indicating its sign (±) in addition to amplitude information. Therefore, first, the point where this sign flag changes from 1 to 0 (in the case shown in FIG. 3) or 0 to 1 (the point where the polarity of the audio signal changes) is detected as the start point of the audio program.

A start control signal e is set at a point of the first polarity change (positive to negative or negative to positive) of the backup system reproduced voice signal h.
And the first change point of the polarity of the active system reproduced audio signal g (corresponding to the standby system reproduced audio signal h) is the stop control signal f.
Further, the output of the oscillator 4 is used as a clock signal.
Then, by counting the number of this clock signal existing between the start control signal e and the stop control signal f with the counter 3, the delay time difference between the standby system reproduced audio signal h and the active system reproduced audio signal g is accurately calculated ( The oscillation frequency of the oscillator 4 is sufficiently high).

With the output of the counter 3 corresponding to this delay time difference, the audio delay memory 7 is controlled to delay the audio data 2j into the audio data # 3k, which is digital / digital.
The analog (D / A) converter 6 converts it into an analog audio signal, and as a preliminary broadcast audio program, switches the switching SW 8 when necessary, and sends (broadcasts) as output audio. The voice delay memory 7 is a digital R
An AM (random access memory) can be used as a delay circuit by first writing a voice signal and then reading it with a delay of a delay time.

[0015]

As described above, according to the present invention, it is possible to match the phases of the broadcast program audio signals of the active system and the standby system, and at the time of switching from the active system to the standby system, a failure (sound is interrupted, It has the effect that the same sound is not repeated).

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is a waveform diagram for explaining a start timing of an audio device.

FIG. 3 is a waveform diagram for explaining an audio delay time measuring method.

[Explanation of symbols]

1, 2 A / D converter 3 counter 4 oscillators 5 control unit 6 D / A converter 7 Voice delay memory 8 Switch SW a Audio equipment start control signal b Audio device # 2 start control signal c Audio device # 1 start control signal d clear signal e Start control signal f Stop control signal g Audio device # 1 (current system) playback audio signal h Audio device # 2 (standby system) playback audio signal i voice data # 1 j Voice data # 2 k Voice data # 3

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Claims (4)

(57) [Claims] 1. An audio phase adjusting device between an active system and a standby system of an audio broadcast program, which converts the reproduced audio signals of the active system and the standby system into digital audio data of the active system and the standby system, and A starting point detecting means for the digital audio data of the active system and the standby system, a time difference measuring means for measuring a time difference existing between the starting points of the standby system and the active system digital audio data, and the standby by the output of the time difference measuring means. A voice phase adjusting device comprising: voice data delaying means for delaying system digital voice data. 2. The start point detecting means is configured to detect the first change point from 0 to 1 or from 1 to 0 of the sign flag of the digital audio data. 1. The audio phase adjusting device according to 1. 3. The time difference measuring means includes a clock signal generating means and a means for counting the clock signals existing between start points of the standby system and active system digital audio data. The audio phase adjustment device according to item 1 or 2. 4. The audio data delay means includes a digital memory, a means for writing the preliminary system digital audio data in the digital memory, and a means for reading out after the delay time of the time difference has elapsed. The audio phase adjustment device according to 1, 2 or 3.