JPS63103457A - Nonaudio suppressing system for voice recorder - Google Patents

Abstract

PURPOSE:To prevent head omission from occurring, by outputting the OR output of control signals from a first and a second nonaudio deciding parts as a third control signal, and recording a delayed data on a recording part only at this time. CONSTITUTION:The data D1 and D2 of sound data are delayed by a time (t) at a buffer memory 3, and the inputted to a recording control part 4 as delayed digital sound data 14. The nonaudio deciding part 6 detects the leading edge point (a) and the nonaudio detecting point (b) of a digital sound data 13, and turns ON a control signal 101 only for points (a)-(b). Similarly, the nonaudio deciding part 7 detects the leading edge point (a') and the nonaudio detecting point (b') of a delayed digital sound data 15 with a timing delayed for the time (t), and turns ON a control signal 102. Since a start/stop control part 8 takes the OR of the control signal 101 and the control signal 102, a start/stop control signal 103 is turned ON only for the points (a)-(b'). The recording control part 4 controls the recording part 5 so that it records the delayed digital sound data 14 only for a time while the start/stop control signal 103 is turned ON.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a silence suppression method for an audio recording device.

(Prior Art) Conventionally, the recording unit of this type of recording device enters a recording pause state, that is, a recording stop state, after a certain period of time has elapsed after determining that the audio signal has changed from a sound state to a silent state, and vice versa. When a silent state changes to a sound state, the recording pause state is canceled after detecting the sound state, and recording is started at the same time as the recording pause is released.

(Problems to be Solved by the Invention) The conventional recording device described above takes a long time from detecting that the audio signal changes from a silent state to a sound state until the recording pause state of the recording section is released. As a result, there is a problem in that the beginning of the voice is not recorded, and the beginning of the voice becomes unclear during playback.

The present invention has been made in view of the above problems, and is a silence suppression method for an audio recording device that suppresses recording in a silent state where no audio signal is obtained, and conversely records the audio signal reliably in a sound state. The purpose is to provide

(Means for Solving the Problems) In order to solve the above-mentioned problems and achieve the above objects, the present invention provides a silence suppression method for an audio recording device that converts an analog audio signal into digital audio data. a first silence determination section that determines the presence or absence of the audio data and outputs a first control signal only when the audio data is obtained; a second silence determination section that determines whether or not the delayed data is present and outputs the second control signal only when the delayed data is obtained; a start/stop control section that outputs the logical sum output of the second control signal as a third M control signal; and a recording control section that causes the recording section to record the delayed data only when the third control signal is obtained. It is characterized by having the following.

(Example) Next, the present invention will be explained with reference to the drawings.

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

An analog audio signal 11 inputted by a microphone 1 is converted into a digital signal by an analog/digital (A/D) converter 2, and inputted as digital audio data 12 and 13 to a buffer memory 3 and a silence determination section 6, respectively. . The buffer memory 3 temporarily stores the digital audio data 12 and outputs it as delayed digital audio data 14 and 15 after a certain period of time has elapsed in the order in which it was input. On the other hand, the silence determination unit 6 that determines the presence or absence of the digital audio data 13 constantly monitors the digital audio data 13, and turns off the output of the control signal 101 when detecting silence. Further, the silence determination unit 7 that determines the presence or absence of the digital audio data 15
Like the silence determination section 6, it constantly monitors the delayed digital audio data 15 in the buffer memory 3, and turns off the output of the control signal 102 when silence is detected.

The start/stop control section 8 has a built-in OR circuit,
The control signal 101 and the control signal 102 are logically summed, and the logical sum output is sent to the recording control section 4 as a start/stop control signal 103. The recording control unit 4 starts/stops the delayed digital audio data 14 with a start/stop control signal 103.
While the start/stop control signal 103 is on, the delayed digital audio data 16 is sent to the recording section 5. Conversely, while the start/stop control signal 103 is off, the delayed digital audio data 14 is transmitted! ! Then, the sending of the delayed digital audio data 16 to the recording unit 5 is stopped. Therefore, the recording unit 5 records the digital audio data 16 only while the start/stop control signal 103 is on.

FIG. 2 is a timing chart of signals of each part in the embodiment of FIG. 1. The operation of the embodiment of the invention shown in FIG. 1 will be explained with reference to FIG. Analog audio signal 11 input from microphone 1 is converted into digital audio data 12 by A/D converter 2 .

As this audio data 12, as shown in FIG.
1. The case where D2 is provided will be explained as an example.

Data DI and D2 of the audio data 12 are delayed by t time in the buffer memory 3. The delayed data D1 and D2 are input to the recording control section 4 as delayed digital audio data 14.

The silence determination unit 6 detects the rising point (a) and the silence detection point (b) of the digital audio data 13, and outputs the control signal 10.
1 is turned on only for the time from point a to point b.

Similarly, the silence determination section 7 detects the rising point (a') and the silence detection point (b') of the delayed digital audio data 15 at a time delayed timing, and turns on the control signal 102.

Since the start/stop control section 8 calculates the logical sum of the control signal 101 and the control signal 102, the start/stop control signal 103 is generated from point a to point b as shown in FIG.
It is turned on only until the point °.

The recording control section 4 controls the recording section 5 so as to record the delayed digital audio data 14 only during the time period when the start/stop control signal 103 is on. Therefore, in the recording section 5, a
Data D1 of the digital audio data 16 is recorded in the time from point C to point b°, and data D2 of the digital audio data 16 is further recorded in the time from point C to point d'.

In the above embodiment, the audio data 14.15 is delayed for a certain period of time by the buffer memory 3, but the time difference between the rise of point a and point a′ shown in FIG. 2 can be determined to be small. The capacity of the buffer memory 3 may be set to an appropriate amount, or the delay time t may be adjusted using an appropriate delay means.

In addition, in the above embodiment, two silence determination sections were set, but
If even one silence determination unit 6 detects silence for a certain period of time or more, the control signal 101 is turned off and the timing of the control signal 103 is adjusted to the delay of the digital audio data 14 output from the buffer memory 3. A similar effect can be obtained by doing so.

(Effects of the Invention) As described above, according to the present invention, it is possible to accurately record the rise of a sound part from a silent part of audio data, and so-called "head missing" parts do not occur. Since recording is not performed when there is no audio data, that is, when there is no sound, less space is required on a recording medium such as a tape, and long-term recording is possible.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a timing chart of signals of various parts in the embodiment shown in FIG. 1...Microphone, 2...Analog/digital converter,
3...Buffer memory, 4...Record v control section,
...Recording section, 6.7... Silence determination section, 8... Start/stop control section, 11... Analog audio data,
12.13...Digital audio data, 14.15...
- Delayed digital audio data, 16... Digital audio data, 101.102... Control signal, 103... Start/stop control signal, DI. D2...data.

Claims (1)

[Claims] an A/D converter that converts an analog audio signal into digital audio data; and a first silence determination unit that determines the presence or absence of the audio data and outputs a first control signal only when the audio data is obtained. a delay unit that delays the audio data by a predetermined time and outputs delayed data; and a second silent device that determines the presence or absence of the delayed data and outputs a second control signal only when the delayed data is obtained. a determination unit; a start/stop control unit that outputs an OR output of the first control signal and the second control signal as a third control signal; 1. A silence suppression method for an audio recording device, comprising a recording control means for recording data in a recording section.