JPH07271399A - Audio recorder with recording mode changeover function - Google Patents

Abstract

PURPOSE:To eliminate an ommision of recording program search, to keep a natural audio recording and to improve the recording efficiency of a recording medium by switching to a recording mode in which the utilization of the recording medium is reduced when audio input is temporarily stopped during a recording. CONSTITUTION:During an encoding process of audio signals, a digital signal processing section 5 performs a sound and silence detection of a frame and the detection results and encoded data are transmitted to a main control circuit 8. The circuit 8 discriminates whether inputted audio signals are stopped for a constant duration or not and controls the operations of a memory control circuit 9 and a semiconductor memory 10. When audio signals are continuously inputted, a recording is performed in a first recording mode to eliminate an omission of recording program search. If input audio signals are stopped for a constant duration during the recording mode, the recording operation of the signals to the memory 10 is stopped and the recording is switched to a second recording mode which reduces the amount of utilization of the memory 10 employing a voice activation or a silence compression, for example.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voice recording device capable of switching recording modes.

[0002]

2. Description of the Related Art Conventionally, there has been known a voice recording apparatus having a voice activated recording function for starting and stopping recording according to a level at which a voice is input. For example, when recording the contents of a meeting, etc. It is used. In such a voice recording device, recording and stopping can be performed according to the input level of voice, so that the recording medium can be used efficiently.

Further, Japanese Patent Laid-Open No. 3-57000 discloses that
Disclosed is a voice recording device having one voice encoding means and capable of switching to an encoding system capable of predicting the recording time when the recording time on the recording medium is short.

[0004]

However, in the above-described conventional voice recording apparatus having a voice activated recording function, the recording is activated in accordance with the level of the voice input to be recorded, so that the voice is uttered and the head is cut off. There was a drawback that caused.

Further, in the voice recording device described in Japanese Patent Laid-Open No. 3-57000, since the encoding is performed and the encoded data is recorded in the memory even when the voice is not input, the memory can be efficiently used. I couldn't.

The voice recording apparatus with the recording mode switching function of the present invention has been made in view of such a problem, and the purpose thereof is to eliminate the recording break and maintain the naturalness of the voice. Another object of the present invention is to provide a voice recording device with a recording mode switching function that can improve the recording efficiency of a recording medium.

[0007]

In order to achieve the above object, a voice recording apparatus with a recording mode switching function according to a first invention comprises a first recording means for recording in a first recording mode and a first recording means. A second recording means for recording in the second recording mode which reduces the use of the storage medium as compared with the first recording mode, and a detection signal indicating that the voice is interrupted for a certain period of time during recording in the first recording mode. Silent time detection means for outputting,
Recording mode switching means for automatically switching from the first recording mode to the second recording mode in response to a detection signal from the silent time detecting means.

Further, a voice recording apparatus with a recording mode switching function according to a second aspect of the present invention comprises an encoding means for encoding the voice information by the first recording means and the second recording means in the first aspect of the invention. I have.

Further, in a voice recording device with a recording mode switching function according to the third invention, the encoding means in the second invention encodes silence and voice in the first recording mode, The recording mode has a means for encoding voiced speech.

Further, in the voice recording apparatus with the recording mode switching function according to the fourth aspect of the invention, the recording mode switching means in the first, second or third aspect of the invention can change the fixed time period in which the voice is interrupted arbitrarily. It has a changing means.

[0011]

That is, the voice recording apparatus with the recording mode switching function according to the first aspect of the present invention includes the first recording mode and the first recording mode.
Second less storage media usage compared to other recording modes
If the detection signal indicating that the sound is interrupted for a certain period of time is output during the recording in the first recording mode, the recording mode is changed from the first recording mode to the second recording mode. It can be switched automatically.

Further, in the voice recording device with the recording mode switching function according to the second invention, in addition to the operation of the first invention, the voice information is encoded at the time of recording. A voice recording device with a recording mode switching function according to the third invention is
In addition to the operation of the second invention, silence and voice are encoded in the first recording mode, and voice is encoded in the second recording mode.

Further, in the voice recording device with the recording mode switching function according to the fourth aspect of the invention, in addition to the operation of the first, second or third aspect of the invention, the fixed time during which the voice is interrupted is arbitrarily changed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a diagram showing the configuration of a voice recording / reproducing apparatus to which the present invention is applied. Referring to FIG. 1, a microphone 1 includes an amplifier (hereinafter referred to as AMP) 2, a low pass filter (hereinafter referred to as LPF) 3, and an analog / digital converter (hereinafter referred to as A / D converter) 4. And is connected to the first terminal of a digital signal processing unit (hereinafter referred to as DSP) 5.

The speaker 13 includes an AMP 12 and a digital / analog converter (hereinafter referred to as D / A converter) 11
And is connected to the second terminal of the DSP 5 via. Further, the third terminal of the DSP 5 is connected to the first terminal of the data input / output buffer 7 via the control circuit 6, and
The fourth terminal of P5 is directly connected to the second terminal of the data input / output buffer 7, and the third terminal of the data input / output buffer 7 is connected to the main control circuit 8.

The main control circuit 8 is connected to a memory control circuit 9 connected to a semiconductor memory 10 which is removable from the voice recording / reproducing apparatus, and a drive circuit 14 connected to a display unit 15.

Further, the main control circuit 8 includes a main power switch 16, a record button REC, a play button PL, and a stop button ST.
The fast forward button FF, the fast reverse button REW, the instruction mark (I mark) button I, the end mark (E mark) button E, and the voice activation (silent compression) button VAD are connected. The main power switch 16 is grounded via the battery BAT, but the various operation buttons described above are directly grounded.

Here, the I mark is one of the index marks for instructions for typists and secretaries, and is used to indicate a priority relationship between a plurality of sentences recorded on a recording medium. , I mark button I is operated to be inserted and recorded between sentences. Therefore, the sentence recorder can specifically instruct the typist or the like by voice using the I mark. On the other hand, the E mark is an index mark for indicating a division between a plurality of sentences and is recorded by operating the E mark button E.

The overall operation of the voice recording / playback apparatus having the above configuration will be described below. First, the analog signal obtained from the microphone 1 is amplified by AMP2, and L
After passing through the PF 3, the signal is converted into a digital signal by the A / D converter 4 and is input to the DSP 5 including a voice encoding means and a detecting means for detecting whether or not voice is input.
The DSP 5 compresses and encodes a voice signal converted into a digital signal during voice recording operation. Also, the encoded voice is expanded and decoded during the reproducing operation.

The control circuit 6 controls the operation of the DSP 5 and sends the compressed voice to the main control circuit 8 via the data input / output buffer 7. The main control circuit 8 having a switching means for switching the recording mode when the sound is interrupted for a certain period of time determines whether or not the sound is interrupted for the certain period of time, and then the DSP 5 and the DSP 5 are operated according to the operation of the plurality of operation buttons and switches. ,
It controls the operations of the memory control circuit 9 and the semiconductor memory 10. That is, the main control circuit 8 gives the memory control circuit 9 a memory control command, an appropriate address signal, and audio compression data,
Data is recorded in the semiconductor memory 10 via the memory control circuit 9 or data recorded in the semiconductor memory 10 is read out, and the DSP 5 is read via the data input / output buffer 7.
Supply to.

The read data decompressed by the DSP section 5 is converted into an analog signal by the D / A converter 11, amplified by the AMP 12, and then output from the speaker 13 as voice.

Further, the main control circuit 8 controls the drive circuit 14 so that the display 15 displays various information such as an operation mode. FIG. 2A is a diagram showing a recording configuration of the semiconductor memory 10 described above. As shown in the figure, the memory space is roughly divided into an index section 10A and an audio data section 10B. A plurality of voice message files 10B1, 10B2, 10B3, ... Are recorded in the voice data section 10B. For example, the voice message file 10B1.
The audio data as shown in FIG. 2B is recorded in.

Further, in the index portion 10A, for each of the plurality of voice message files recorded in the voice data B, the operation start position information 10A1 and the operation end position information 10A2, as well as the code mode and the operation condition are recorded. . In addition, operation position information 10A3 indicating the current operation position with respect to the audio data portion 10B is recorded.

The following describes the format (initialization) operation for the semiconductor memory 10 and the operation of the main control circuit 8 when a specific operation mode is set thereafter. When the battery BAT is set and power is supplied, the main control circuit 8 starts the operation shown in the flowchart of FIG.

That is, first, the external conditions of the main control circuit 8 and the internal storage unit are initialized (step S1). However, at this point, the main power switch 16 for instructing the power supply to the entire audio recording / reproducing apparatus is in the OFF state. After completing the initial setting, the main control circuit 8 detects whether or not the main power switch 16 is turned on (step S).
2). When it is detected that the main power switch 16 is in the ON state as a result of the detection, the power switch (not shown) provided between the battery BAT for supplying power to the entire audio recording / reproducing apparatus and each circuit is turned ON. Then, the information of the index portion 10A of the semiconductor memory 10 is read (step S3). That is, the operation start position information 10A1, the operation end position information 10A2, the code mode, the operation condition, and the like are read.

At this time, based on the data read from the semiconductor memory 10, whether the index is normally recorded in the semiconductor memory 10, that is, the semiconductor memory 1
It is determined whether the 0 format is normal (step S4).

Here, when the unformatted data is stored in the semiconductor memory 10, it is determined that it is not normal, and in that case, the information indicating the usage condition is recorded in the index portion 10A of the semiconductor memory 10, and It is confirmed whether or not the memory format, which is the process of recording "0" in the audio data section 10B, is performed (step S
5). In this case, the main control circuit 8 controls the drive circuit 14 to cause the display unit 15 to display a confirmation display as to whether or not to perform the memory format.

Here, if the button (also used as the recording button REC) for confirming the memory formatting process is pressed by the person who recorded the text, the semiconductor memory 10 is formatted (step S6), and after this formatting is completed, the drive circuit is completed. 14 is controlled to display the initialization setting completion display on the display 15 (step S7).

When the button (also used as the stop button ST) for confirming not to format the memory is pressed by the person who recorded the text, the drive circuit 14 is controlled to display the display 1.
An error message indicating that the semiconductor memory 10 is not normal is displayed in step 5 (step S8), and the semiconductor memory 1
Instruct and display that 0 should be replaced. And
Battery BAT for supplying power to the entire audio recording / playback device
And a power switch (not shown) provided between
Set to FF. Next, in order to replace the semiconductor memory 10, the main power switch 16 is waited for being turned off by the text creator (step S9), and when it is detected that it is turned off, the process returns to step S2.

On the other hand, after the semiconductor memory 10 is normally initialized, the information read from the index unit 10 (operation position information 1) is displayed after the completion of initialization is displayed (step S7).
0A3) to detect the operating position (step S10),
After that, it waits until one of the operation buttons of the device is pressed (step S11). When it is detected that one of the operation buttons is pressed, it is first detected whether or not the recording button REC is pressed (step S12), and if the recording button REC is pressed, Control DSP5 to A
The voice information input from the / D conversion unit 4 is compressed, and the memory control circuit 9 is controlled to record the voice information in the voice data unit 10B of the semiconductor memory 10 (step S13).

When the recording button REC is not pressed, it is then detected whether or not the reproduction button PL is pressed (step S14). Here, if the play button PL is pressed, the memory control circuit 9 is controlled to read the recorded data from the audio data section 10B of the semiconductor memory 10, and the data is sent to the DSP 5 for decompression processing. A converter 1
1. Playback processing for sending voice information to 1 (step S1)
5).

When the play button PL is not pressed, it is detected whether the fast-forward button FF is pressed (step S16). If the fast-forward button FF is pressed, a fast-forward process is carried out in which the operation positions are sequentially fast-forwarded at an appropriate speed (for example, 20 times speed of reproduction) (step S17). If the fast-forward button FF is not pressed, it is detected whether or not the fast-return button REW is pressed (step S18). If the fast-reverse button REW is pressed, the fast-reverse processing is performed to move the operating position at the same speed as in the case of the fast-forward (step S19).

Steps S13, S15, S17, S
When the stop button ST is pressed, each process of 19 is skipped and the process returns to step S11. If the pressed button is not a button for recording, reproducing, fast-forwarding, fast-rewinding, etc., the main power switch is turned off or the state of various setting buttons is detected (step S20).

Here, when the main power switch 16 is turned off, the semiconductor memory 1 is controlled by controlling the memory control circuit 9.
The information in the index section 10A of 0 is erased, and the index information stored in the unillustrated storage section in the main control circuit 8 is transferred to the index section 10A of the semiconductor memory 10 and recorded (step S21). When this index transfer process is completed, the power switch (not shown) for supplying power to the entire apparatus, that is, each circuit is turned off (step S22). Then, the process returns to step S2.

In step S20, when it is determined that the main power switch 16 is not OFF, the setting button is detected and the state thereof is stored in the unillustrated storage section in the main control circuit 8, and then in step S11. Return. Here, the setting button is not a button actually provided on the device, but a recording button REC, a play button PL, a stop button ST, a fast forward button FF, a fast rewind button REW, an I mark button I, an E mark button E,
Among the voice activation (silence compression) buttons VAD, these buttons are substituted by some simultaneous pressing.

Next, the recording process of step S13 of FIG. 3 will be described in more detail with reference to the flowchart of FIG. When the main control circuit 8 detects that the recording button REC has been pressed and the recording mode has been set (step S31), the operation is shifted to the recording process, and the voice recording condition at that time (for example, voice activation or silent compression) is first set. Or the use of adaptive variable type of audio compression rate). In this embodiment, at the start of the operation, voice activation or silence compression is not performed,
Therefore, since the first recording mode in which no head cut occurs is preset, a signal indicating the first recording mode is sent to the DSP 5 as a condition for voice recording (step S3).
2).

Next, the index information (operating position information) stored in the storage section inside the main control circuit 8 is read out and written in the index section 10A as operation start information 10A1 indicating the recording start position (step S33).
Next, the silent period count value n for measuring the silent period
Is set to the initial setting value 0 (step S34), and the value VF representing the switching information of the apparatus is set to the initial setting value 0 (step S35). In this embodiment, the VF is set to 0 in the initial setting mode, that is, the first recording mode, but when the VF becomes 1, the voice starting or the silent compression mode is set as the second recording mode. Switched, V
When F is 2 or more, the recording state is switched to the stop state.

Next, the compressed voice data is transferred from the DSP 5 to the main control circuit 8 (step S36). In the present embodiment, the coding in the DSP 5 is preferably a code-excited linear predictive coding method (CELP: Code Excited Lin) in which an excitation (residual) signal is vector-quantized using a codebook.
Although an analysis-synthesis type speech coding system such as ear predictive coding is used, a waveform coding type compression system such as ADPCM may be adopted. In CELP audio encoding, an input audio signal within a predetermined time (for example, 20 msec) is treated as one frame (for example, 160 pieces of data are regarded as one frame of data at a sampling frequency of 8 kHz), and this one frame is used. The following parameters are derived using the data of. That is, first, the linear prediction coefficient (LPC)
(Short-term prediction filter coefficient or reflection coefficient etc.) is calculated and quantized, and the parameter is output. Then, the degree of similarity of excitation (residual) signal models (codebooks) of some sound source information is determined as the sound source information data, and the most similar model is found. The excitation (residual) signal model number (index) and the gain information at that time are quantized and encoded.

The DSP 5 detects whether or not one frame is silent during this encoding process, and sends the detection result to the main control circuit 8 together with the encoded data. As a method of detecting whether or not there is silence, whether there is silence by calculating the energy of one frame of data (sum of squares of each sample data) or the maximum value in one frame and the cross-correlation between the audio signal and the residual signal. It is determined whether or not there is no sound, and the sound is encoded as 1 and output.

Based on the data transferred from the DSP 5 by the above method, the main control circuit 8 determines whether the data is silent (step S37). If there is no sound, the silent cycle count value n is incremented by 1 to count up (step S38). If there is no sound, the sound cycle count value n is reset to 0, which is the initial setting value (step S39). Then, in order to determine whether or not the silence period has exceeded a certain period of time, the silence period count value n is, for example, a determination value LIM = 500 (meaning that silence for 500 frames continues, and a silence period of 10 seconds is determined). (Corresponding to time) or more is determined (step S
40). This judgment value LIM takes a range of about 5 to 65535. About 100 to 3000 is preferable, and about 150 to 500 is particularly preferable. In this embodiment, the judgment value LIM
= 500 is adopted.

When the voice is input or the silence is input, the determination in step S40 is NO while the value does not exceed the predetermined period value and the VF in the next step S42.
If YES, the determination is YES, and the next step S43.
To execute. In step S43, the voice coded data transferred from the DSP 5 together with the control command to the memory control circuit 9 is output to the memory control circuit 9, and the memory control circuit 9 records the coded data in the semiconductor memory 10. Next, the operating position information stored in the internal storage unit (not shown) of the main control circuit 8 is updated (step S44). The value to be updated is the operation end position information 1 of the index section 10A.
0A2 and operating position information 10A3 are updated. And
It is detected whether or not the stop (STOP) button ST has been pressed (step S45), and if not pressed, the flow returns to step S36 to repeat the above operation.

If the silent period continues for a certain period or longer and the determination value LIM becomes 500 or more, 1 is added to the switching information value VF (step S41). As a result, since VF = 1, the determination in step S42 as to whether the VF value is 0 is NO, and step S46 is executed. Since VF = 1 here, the determination in step S46 is Y.
It becomes ES, where n is reset to 0. In this case, the encoded data is not stored in the semiconductor memory 10 and step S45 is executed. Then, if the stop button ST is not pressed, the step S36 and thereafter are executed.

Here, if the silent period is still continuing, the determination in step S40 becomes YES again, so that 1 is further added to the switching information value VF in step S41, and VF = 2. In this case, the determinations in steps S42 and S46 are NO, and in step S47, the operating position information stored in the internal storage unit (not shown) of the main control circuit 8 is updated. That is, the operation end position information 10A2 and the movement position information 1 of the index portion 10A.
0A3 is updated, the end position is determined, and this recording process is exited.

The value of the judgment value LIM can be varied depending on the frequency of occurrence of silence when silence occurs continuously. For example, when VF is 0, the judgment value LIM is 500, and when VF is 1, the judgment value LIM is 50.
You can set different values for each.
For that purpose, for example, if YES is determined in step S40, the determination value LIM may be switched from 500 to 50. On the contrary, when it is desired to make the time from the second recording mode to the recording stop mode longer than the time to switch from the first recording mode to the second recording mode, for example, from the determination value LIM of 500 1
It should be set to switch to 000. By doing so, it is possible to automatically switch the mode according to the environment. Further, by setting the determination value LIM when VF is 0 to a value smaller than 500, for example, about 200 in advance, for a speaker with a lot of silence while thinking, the second value such as the voice activation mode is set. The recording efficiency of the recording medium may be improved by making it easier to shift to the recording mode.

Further, in the above-mentioned embodiment, the push button is assumed as the operation button, but it is not limited to this, and it is also possible to use a slide type operation button, for example. As described above, the voice recording apparatus with the recording mode switching function of the present embodiment includes the first recording means (main control circuit 8 and DSP 5) for recording in the first recording mode in which no head cut occurs, and the first recording. A second recording mode (main control circuit 8, DSP 5) for recording in a second recording mode for reducing the use of the semiconductor memory 10 as a storage medium as compared with the mode, for example, a voice activation mode,
Silence time detection means (DSP) that outputs a detection signal indicating that voice has been interrupted for a certain period of time during recording in the first recording mode.
5) and a detection signal from the DSP 5 (output signal of code 0)
In response to this, a recording mode switching means (main control circuit 8) for automatically switching from the first recording mode to the second recording mode is provided.

The first recording means and the second recording means are encoding means (DSP) for encoding voice information during recording.
5). Also, this encoding means (DSP5)
Encodes silence and voice in the first recording mode, and encodes voice in the second recording mode.

Further, the main control circuit 8 as the recording mode switching means has a time changing means capable of arbitrarily changing the above-mentioned fixed time during which the voice is interrupted. Therefore, the above-described voice recording apparatus with the recording mode switching function of the present embodiment records in the first recording mode in which the recording is not clogged when the voice is continuously input, and the recording is performed in this recording mode. When it is detected that no sound is input during a certain period of time, recording in the semiconductor memory 10 is stopped and a second recording mode for reducing the usage of the semiconductor memory 10, for example, a recording mode such as voice activation or silence compression. Is automatically switched to. Therefore, for example, it is possible to prevent the semiconductor memory 10 from being wasted when, for example, recording the dictation and forgetting to press the stop button, and when the speaker is used with a lot of silence, or while thinking. The semiconductor memory 10 can be efficiently used even when recording is performed.

The following technical ideas are derived from the above-mentioned specific embodiments, and the following effects are achieved. That is, the first audio recording device with the recording mode switching function
The configuration of the first recording at least in the first recording mode
Sound recording means, a second sound recording means for recording in the second sound recording mode which reduces the use of the storage medium as compared with the first sound recording mode, and a sound is interrupted for a certain time during the sound recording in the first sound recording mode. And a recording mode switching means for automatically switching from the first recording mode to the second recording mode in response to the detection signal from the silent time detecting means. In this case, the recording is not cut off, the naturalness of the voice is maintained, and the recording efficiency of the recording medium is improved.

In addition, in the second configuration of the voice recording device with the recording mode switching function, in addition to the above-mentioned first configuration, the first recording means and the second recording means encode the voice information at the time of recording. It has an encoding means, and in this case, the audio signal is compressed and the recording efficiency of the recording medium is further improved.

In addition, in the third configuration of the voice recording device with the recording mode switching function, in addition to the second configuration, the encoding means encodes silence and voice in the first recording mode, The second recording mode has means for performing voice coding, and in this case, in addition to the effect of the second configuration, the recording efficiency of the recording medium is further improved.

The fourth configuration of the voice recording apparatus with the recording mode switching function is, in addition to the first, second, or third configuration, a time in which the recording mode switching means can arbitrarily change the above-mentioned fixed time. In this case, since the changing means is provided and it is possible to cope with the situation, the recording efficiency of the recording medium is further improved in addition to the effect of the first, second, or third configuration described above.

[0052]

According to the first aspect of the invention, the recording is not cut off, the naturalness of the voice is maintained, and the recording efficiency of the recording medium is improved. According to the invention described in claim 2, in addition to the effect of the invention described in claim 1, there is an effect that the audio signal is compressed and the recording efficiency of the recording medium is further improved.

According to the third aspect of the invention, in addition to the effect of the second aspect of the invention, the recording efficiency of the recording medium can be further improved. According to the invention described in claim 4, in addition to the effect of the invention described in claim 1, claim 2, or claim 3, the efficiency of the recording medium is further improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a voice recording / reproducing apparatus to which the present invention is applied.

FIG. 2A is a diagram showing a recording configuration of a semiconductor memory, and FIG. 2B is a diagram showing an example of audio data recorded in a semiconductor memory.

FIG. 3 is a flowchart showing a formatting operation and then an operation of the main control circuit when a specific operation mode is set.

FIG. 4 is a flowchart showing a recording operation of this embodiment.

[Explanation of symbols]

1 ... Microphone, 2, 12 ... Amplifier (AMP), 3 ...
Low-pass filter (LPF), 4 ... Analog / digital (A / D) converter, 5 ... Digital signal processor (DS)
P), 6 ... Data input / output buffer, 8 ... Main control circuit, 9
... memory control circuit, 10 ... recording medium (semiconductor memory),
11 ... Digital / analog (D / A) converter, 13 ... Speaker, 14 ... Drive circuit, 15 ... Display.

Claims (4)

[Claims] 1. A first recording means for recording in a first recording mode, and a second recording means for recording in a second recording mode which uses less storage medium than in the first recording mode. In the first recording mode, the second recording mode is changed from the first recording mode in response to the silent time detecting means for outputting a detection signal indicating that the voice is interrupted for a certain period of time during the recording and the detection signal from the silent time detecting means. A voice recording device with a recording mode switching function, comprising: a recording mode switching means for automatically switching to a recording mode. 2. The voice recording with a recording mode switching function according to claim 1, wherein the first recording means and the second recording means have encoding means for encoding voice information during recording. apparatus. 3. The encoding means has means for encoding silence and voice in the first recording mode and encoding voice in the second recording mode.
An audio recording device with the described recording mode switching function. 4. A voice with a recording mode switching function according to claim 1, wherein the recording mode switching means has a time changing means capable of arbitrarily changing the fixed time. Recording device.