JP5653050B2 - Speech decoding switching device, speech decoding switching system, and speech decoding switching method used therefor - Google Patents

Description

  The present invention relates to a speech decoding switching device, a speech decoding switching system, and a speech decoding switching method used therefor, and more particularly to switching of a decoding circuit that decodes a speech signal.

  A configuration example of a speech decoding switching system related to the present invention is shown in FIG. 5, and its operation is shown in FIG. The operation of the speech decoding switching system relating to the present invention will be described with reference to FIGS. Here, the speech decoding circuit A11 and the speech decoding circuit B13 are circuits used for different decoding systems, and the switch 15 outputs a switching instruction from the decoding operation control circuit 31 to the speech decoding circuit A11 or the speech decoding circuit B13. Then, the switch 16 outputs the output signal from the speech decoding circuit A11 or the output signal from the speech decoding circuit B13 to the speech signal output terminal 18 in accordance with the switching instruction from the decoding operation control circuit 31.

  The decoding circuit before switching the decoding system, for example, the speech decoding circuit A11, decodes the speech code A input from the speech code A input terminal 12, and outputs the decoded signal from the speech signal output terminal 18 via the switch 16. (Step S31 in FIG. 6).

  The decoding operation control circuit 31 switches the switch 15 and the switch 16 at any timing within the coding scheme switching section based on the coding scheme switching section information input from the coding scheme switching section information input terminal 17 ( FIG. 6 step S32). In the system, the timing for switching the switch is not particularly mentioned.

  After the switch 15 and the switch 16 are switched, the decoding circuit after the switching of the decoding system, for example, the speech decoding circuit B13 decodes the speech code B input from the speech code B input terminal 14 and outputs the output speech via the switch 16 The result is output to the suppression circuit 32 (step S33 in FIG. 6).

  The output voice suppression circuit 32 suppresses the voice signal input from the switch 16 as necessary according to the control from the decoding operation control circuit 31, and outputs it from the voice signal output terminal 18 (step S34 in FIG. 6). Specifically, after the decoding operation control circuit 31 suppresses the output audio signal from the switch 16 in order to reduce the discontinuity of the audio signal due to the switching of the decoding circuit during the encoding method switching period. The output sound suppression circuit 32 is controlled so as to output to the sound signal output terminal 18.

  As described above, in the speech decoding switching system related to the present invention, in order to reduce the discontinuity of the output speech when the speech code decoding method is switched, a certain period including the switching time of the decoding circuit is reduced. The output signal is simply suppressed. An example of simply suppressing the output signal from the encoding circuit when switching the encoding circuit is described in Patent Document 1 below.

JP 9-152899 A

  However, in the speech decoding switching system related to the present invention, if the speech signal is suppressed while the person is actually speaking, the voiced speech signal is suppressed. There is.

  Accordingly, an object of the present invention is to solve the above-described problems and to perform a speech decoding switching device and speech that can perform switching of a speech decoding circuit when a speech decoding method is switched without accompanying discontinuity. It is an object to provide a decoding switching system and a speech decoding switching method used for them.

A speech decoding switching device according to the present invention is a speech decoding switching device having a plurality of types of speech decoding circuits,
A comparison means for comparing the level of the transmitted voice and the level of the received voice;
Decoding operation switching means for instructing the switching at a timing suitable for switching from the currently used speech decoding circuit to another speech decoding circuit based on the comparison result of the comparing means.

Another speech decoding switching device according to the present invention is a speech decoding switching device having a plurality of types of speech decoding circuits,
A first memory for storing a temporal transition of a transmission voice level;
A second memory for storing the temporal transition of the received voice level;
Analyzing means for analyzing the temporal transition of the level of the transmission voice stored in the first memory and the temporal transition of the level of the reception voice stored in the second memory;
Decoding operation switching means for instructing switching at a timing suitable for switching from the currently used speech decoding circuit to another speech decoding circuit based on the analysis result of the analyzing means.

  A speech decoding switching system according to the present invention includes the speech decoding switching device described above.

A speech decoding switching method according to the present invention is a speech decoding switching method used for a speech decoding switching device having a plurality of types of speech decoding circuits,
The speech decoding switching device compares the transmission speech level with the received speech level, and switches from the speech decoding circuit currently in use to another speech decoding circuit based on the comparison result of the comparison processing. And a decoding operation switching process for instructing the switching at a timing suitable for the above.

Another speech decoding switching method according to the present invention is a speech decoding switching method used for a speech decoding switching device having a plurality of types of speech decoding circuits,
The speech decoding switching device includes a process of storing a temporal transition of a transmission voice level in a first memory, a process of storing a temporal transition of a received voice level in a second memory, and the first An analysis process for analyzing a temporal transition of the level of the transmission voice stored in the first memory and a temporal transition of the level of the reception voice stored in the second memory, and an analysis result of the analysis process And a decoding operation switching process for instructing the switching at a timing suitable for switching from the currently used speech decoding circuit to another speech decoding circuit.

  By adopting the above-described configuration and operation, the present invention can achieve an effect that the speech decoding circuit can be switched when the speech decoding method is switched without a sense of discontinuity.

It is a block diagram which shows the structural example of the speech decoding switching apparatus by the 1st Embodiment of this invention. It is a flowchart which shows the operation example of the speech decoding switching apparatus by the 1st Embodiment of this invention. It is a block diagram which shows the structural example of the speech decoding switching apparatus by the 2nd Embodiment of this invention. It is a flowchart which shows the operation example of the speech decoding switching apparatus by the 2nd Embodiment of this invention. It is a block diagram which shows the structural example of the audio | voice decoding switching system relevant to this invention. It is a flowchart which shows the operation example of the speech decoding switching system relevant to this invention.

  Next, embodiments of the present invention will be described with reference to the drawings. First, the outline of the speech decoding switching apparatus according to the present invention will be described. The speech decoding switching device according to the present invention is configured to switch speech decoding circuits without a sense of discontinuity by comparing or analyzing transmitted and received speech levels when the speech decoding method is switched.

  In the present invention, the reception-side audio level measurement circuit measures the level of the audio signal output via the second switch, and inputs the measured audio signal level to the transmission / reception audio level comparison circuit as reception-side audio level information. To do. The transmission side audio level information input via the transmission side audio level information input terminal is input to the transmission / reception audio level comparison circuit as it is.

  The transmission / reception audio level comparison circuit compares the reception side audio level information input from the reception side audio level measurement circuit with the transmission side audio level information input from the transmission side audio level information input terminal, and switches the comparison result to the decoding operation switching Output to the circuit.

  The decoding operation switching circuit includes the first switch and the second switch based on the coding scheme switching section information input from the coding scheme switching section information input terminal and the transmission / reception voice level comparison result input from the transmission / reception voice level comparison circuit. Switch each switch.

  That is, in the speech decoding switching device according to the present invention, the speech decoding method is performed without a sense of discontinuity by comparing or analyzing the speech levels of transmission and reception and detecting the timing suitable for the switching operation of the speech decoding circuit. It is possible to perform switching of the speech decoding circuit at the time of switching.

  FIG. 1 is a block diagram showing a configuration example of a speech decoding switching apparatus according to the first embodiment of the present invention. In FIG. 1, a speech decoding switching device according to the first embodiment of the present invention includes a speech decoding circuit A11, a speech code A input terminal 12, a speech decoding circuit B13, a speech code B input terminal 14, and a switch. 15, 16, encoding method switching section information input terminal 17, audio signal output terminal 18, decoding operation switching circuit 19, reception side audio level measurement circuit 20, transmission side audio level information input terminal 21, The transmission / reception voice level comparison circuit 22 is configured.

  Note that the speech decoding switching device according to the first embodiment of the present invention switches to the corresponding speech decoding circuit every time the speech decoding method is switched, and the speech decoding that performs such an operation. It can also be applied to a switching system.

  The speech decoding circuit A11 decodes the speech code A input from the speech code A input terminal 12, and outputs the decoded signal from the speech signal output terminal 18 via the switch 16.

  The speech decoding circuit B 13 decodes the speech code B input from the speech code B input terminal 14 and outputs the decoded signal from the speech signal output terminal 18 via the switch 16.

  The reception-side audio level measurement circuit 20 measures the level of the audio signal output via the switch 16 and inputs the measured audio signal level to the transmission / reception audio level comparison circuit 22 as reception-side audio level information. The transmission side audio level information input via the transmission side audio level information input terminal 21 is input to the transmission / reception audio level comparison circuit 22 as it is.

  The transmission / reception audio level comparison circuit 22 compares the reception-side audio level information input from the reception-side audio level measurement circuit 20 with the transmission-side audio level information input from the transmission-side audio level information input terminal 21, and the comparison result is obtained. The data is output to the decoding operation switching circuit 19.

  The decoding operation switching circuit 19 is based on the coding scheme switching section information from the communication partner input from the coding scheme switching section information input terminal 17 and the transmission / reception voice level comparison result input from the transmission / reception voice level comparison circuit 22. Switch 15 and switch 16 are switched.

  Here, the speech decoding circuit A11 and the speech decoding circuit B13 are circuits used for different decoding systems, and the switch 15 outputs a switching instruction from the decoding operation switching circuit 19 to the speech decoding circuit A11 or the speech decoding circuit B13. Then, the switch 16 outputs the output signal from the speech decoding circuit A11 or the output signal from the speech decoding circuit B13 to the speech signal output terminal 18 in accordance with the switching instruction from the decoding operation switching circuit 19.

  FIG. 2 is a flowchart showing an operation example of the speech decoding switching apparatus according to the first embodiment of the present invention. The operation of the speech decoding switching apparatus according to the first embodiment of the present invention will be described with reference to FIG. 1 and FIG.

  The processing operation shown in FIG. 2 can also be realized by executing a program by a CPU (central processing unit) of a speech decoding switching device (not shown). Hereinafter, as an example, the operation in the case of switching from the speech decoding circuit A11 to the speech decoding circuit B12 will be described.

  The decoding circuit before switching of the decoding system, that is, the speech decoding circuit A11 decodes the speech code A input from the speech code A input terminal 12, and outputs the decoded signal from the speech signal output terminal 18 via the switch 16. (FIG. 2, step S1).

  The reception-side audio level measurement circuit 20 measures the level of the audio signal output via the switch 16, and inputs the measured audio signal level to the transmission / reception audio level comparison circuit 22 as reception-side audio level information (step in FIG. 2). S2). The reception side voice level information referred to here corresponds to the level of a voice signal obtained by decoding a voice code received from the other party in a general voice call.

  The transmission side audio level information input via the transmission side audio level information input terminal 21 is directly input to the transmission / reception audio level comparison circuit 22 (step S3 in FIG. 2). The transmission side voice level information referred to here corresponds to the level of a voice signal transmitted from the user to the other party in a general voice call.

  The transmission / reception audio level comparison circuit 22 compares the reception-side audio level information input from the reception-side audio level measurement circuit 20 with the transmission-side audio level information input from the transmission-side audio level information input terminal 21, and the comparison result is obtained. The data is output to the decoding operation switching circuit 19 (step S4 in FIG. 2).

  Hereinafter, the processing operation of step S4 will be specifically described. The transmission-side audio level information input via the transmission-side audio level information input terminal 21 corresponds to the volume of voice in the direction of transmission from the user to the other party in a general voice call, that is, the volume of the user's own voice. The reception-side audio level information measured by the reception-side audio level measurement circuit 20 corresponds to the loudness of the voice in the direction in which it receives from the other party, that is, the other party's voice.

  In a general conversation, the speaker is either one of you or the other, so comparing these two audio level informations compares the volume of your voice with that of the other party. In other words, it will be determined whether you or the other person is speaking.

  That is, when the transmission side audio level information is larger than the reception side audio level information, it is considered that the user is talking and the other party is listening. If the transmission side audio level information is smaller than the reception side audio level information, it is considered that the user is listening to the other party and the other party is speaking. Thus, comparing the voice levels of transmission and reception corresponds to an operation of specifying a speaker in a voice call.

  The decoding operation switching circuit 19 includes the switch 15 and the switch 15 based on the coding system switching section information input from the coding system switching section information input terminal 17 and the transmission / reception voice level comparison result input from the transmission / reception voice level comparison circuit 22. 16 is switched (step S5 in FIG. 2).

Hereinafter, the processing operation of step S5 will be specifically described. It is assumed that information indicating a coding system switching section is input from the coding system switching section information input terminal 17. The speech code is input from both the speech code A input terminal 12 and the speech code B input terminal 14 during the coding system switching section, and the switching operation of the decoding circuit is performed during the coding system switching section. To do.
In the coding system switching section, the decoding operation switching circuit 19 refers to the transmission / reception voice level comparison result input from the transmission / reception voice level comparison circuit 22 and determines whether the timing is suitable for switching the decoding circuit. The decoding circuit is switched.

  Specifically, when the transmission side audio level information is larger than the reception side audio level information within the coding scheme switching section, the switch 15 and the switch 16 are switched, and the decoding circuit is changed from the audio decoding circuit A11 to the audio decoding circuit B13. Switch to.

  In this case, since the transmission side audio level information is larger than the reception side audio level information, it is considered that the speaker is himself and the other party is listening to his own story, that is, not talking. That the other party is not speaking, that is, it is considered that the voice code received from the other party does not include the other party's voice but only the surrounding background noise.

  In general, the background noise is low in signal level compared to the voice signal when a human is speaking, so it is possible to reduce the discontinuity and incongruity caused by switching of the decoding circuit. Switching can be performed.

  The switched decoding circuit, that is, the speech decoding circuit B13 decodes the speech code B input from the speech code B input terminal 14 and outputs the decoded signal from the speech signal output terminal 18 via the switch 16 (step in FIG. 2). S6).

  As described above, in the present embodiment, the switching of the decoding circuit is performed in order to switch the decoding circuit in anticipation of a timing suitable for the switching operation of the decoding circuit, for example, the reception signal from the other party does not include a voice signal. There is an effect that it is possible to reduce the discontinuity or discomfort of the audio signal that sometimes occurs.

  FIG. 3 is a block diagram showing a configuration example of a speech decoding switching apparatus according to the second embodiment of the present invention. In FIG. 3, the speech decoding switching device according to the second embodiment of the present invention adds a reception-side speech level information storage memory 24 and a transmission-side speech level information storage memory 25, and transmits / receives speech level comparison circuit 22. 1 is the same as that of the speech decoding switching apparatus according to the first embodiment of the present invention shown in FIG. It is.

  FIG. 4 is a flowchart showing an operation example of the speech decoding switching apparatus according to the second embodiment of the present invention. The operation of the speech decoding switching apparatus according to the second embodiment of the present invention will be described with reference to FIG. 3 and FIG.

  The processing operation shown in FIG. 4 can also be realized by executing a program by a CPU (Central Processing Unit) (not shown) of the speech decoding switching device. Hereinafter, as an example, the operation in the case of switching from the speech decoding circuit A11 to the speech decoding circuit B12 will be described.

  The decoding circuit before switching of the decoding system, that is, the speech decoding circuit A11 decodes the speech code A input from the speech code A input terminal 12, and outputs the decoded signal from the speech signal output terminal 18 via the switch 16. (FIG. 4, step S11).

  The reception-side audio level measurement circuit 20 measures the level of the audio signal output via the switch 16, and stores the measured audio signal level in the reception-side audio level information storage memory 24 as reception-side audio level information (see FIG. 4 step S12). The reception-side audio level information storage memory 24 can store a plurality of reception-side audio level information output from the reception-side audio level measurement circuit 20 in the past.

  The transmission side audio level information input via the transmission side audio level information input terminal 21 is directly input to the transmission side audio level information storage memory 25 (step S13 in FIG. 4). The transmission-side audio level information storage memory 25 can store a plurality of transmission-side audio level information input from the transmission-side audio level input terminal 21 in the past.

  The transmission / reception audio level analysis circuit 23 analyzes the plurality of reception side audio level information input from the reception side audio level information storage memory 24 and the plurality of transmission side audio level information input from the transmission side audio level information storage memory 25. The analysis result is output to the decoding operation switching circuit 19 (step S14 in FIG. 4).

  Hereinafter, the processing operation of step S14 will be specifically described. The difference between the present embodiment and the first embodiment of the present invention described above is that a plurality of transmission-side audio level information and reception-side audio level information storage memories stored in the transmission-side audio level information storage memory 25 24, it is possible to analyze the past temporal transitions of the audio level on the transmission side and the audio level on the reception side by referring to the plurality of reception side audio level information stored in FIG. This is in that it is possible to determine a timing that is more suitable for switching the conversion method.

  For example, if the transmitter audio level is higher than the receiver audio level for a certain period in the past and the transmitter audio level gradually increases with time, Therefore, it can be determined that there is a high possibility that the other party is listening to the story. The transmission / reception voice level analysis circuit 23 outputs the information on the optimal timing analyzed in this way to the decoding operation switching circuit 19 as an analysis result.

  The decoding operation switching circuit 19 includes a switch 15 and a switch 15 based on the coding scheme switching section information input from the coding scheme switching section information input terminal 17 and the transmission / reception voice level analysis result input from the transmission / reception voice level analysis circuit 23. 16 is switched (step S15 in FIG. 4).

  The switched decoding circuit, that is, the speech decoding circuit B13 decodes the speech code B input from the speech code B input terminal 14 and outputs the decoded signal from the speech signal output terminal 18 via the switch 16 (step in FIG. 4). S16).

  Thus, in the present embodiment, since the decoding circuit is switched based on the analysis result input from the transmission / reception voice level analysis circuit 23, compared with the above-described first embodiment of the present invention, The decoding circuit can be switched at an appropriate timing.

  INDUSTRIAL APPLICABILITY The present invention can be applied to a speech decoding apparatus or system having a plurality of types of speech decoding circuits, particularly a speech decoding switching apparatus or system that may switch between a plurality of types of speech decoding circuits during a voice call.

11 Speech decoding circuit A
12 Voice code A input terminal 13 Voice decoding circuit B
DESCRIPTION OF SYMBOLS 14 Voice code B input terminal 15,16 Switch 17 Coding system switching area information input terminal 18 Audio signal output terminal 19 Decoding operation switching circuit 20 Reception side voice level measurement circuit 21 Transmission side voice level information input terminal 22 Transmission / reception voice level comparison Circuit 23 Transmission / reception audio level analysis circuit 24 Reception side audio level information storage memory 25 Transmission side audio level information storage memory

Claims (5)

A speech decoding switching device having a plurality of types of speech decoding circuits,
A comparison means for comparing the level of the transmitted voice and the level of the received voice;
Switching instruction and decoding operation switching means performs the from the speech decoding circuit currently in use to another of said speech decoding circuit,
Coding method switching section information, which is information related to a coding system switching section, which is a section in which both the voice code of the received voice and the voice code of the transmission voice from the communication partner are input Input terminal to input to,
Have,
The decoding operation switching means, in the coding scheme switching section indicated in the coding scheme switching section information, based on the comparison result of the comparing means, from the currently used speech decoding circuit to the other speech decoding circuit A speech decoding switching device characterized by determining a timing suitable for switching to a circuit and instructing switching of the speech decoding circuit at the timing . A speech decoding switching device having a plurality of types of speech decoding circuits,
A first memory for storing a temporal transition of a transmission voice level;
A second memory for storing the temporal transition of the received voice level;
Analyzing means for analyzing the temporal transition of the level of the transmission voice stored in the first memory and the temporal transition of the level of the reception voice stored in the second memory;
Decoding operation switching means for instructing switching from the speech decoding circuit currently in use to the other speech decoding circuit;
Coding method switching section information, which is information related to a coding system switching section, which is a section in which both the speech code of the received speech and the speech code of the transmission speech from the communication partner are input, is the decoding operation switching means. Input terminal to input to,
Have
The decoding operation switching means, in the coding scheme switching section indicated by the coding scheme switching section information, based on the analysis result of the analyzing means, from the speech decoding circuit currently in use to the other speech decoding circuit A speech decoding switching device characterized by determining a timing suitable for switching to a circuit and instructing switching of the speech decoding circuit at the timing. A speech decoding switching system comprising the speech decoding switching device according to claim 1 or 2. A speech decoding switching method used for a speech decoding switching device having a plurality of types of speech decoding circuits,
The speech decoding switching device is
A comparison process that compares the level of the transmitted voice with the level of the received voice;
A decoding operation switching process for instructing switching from the speech decoding circuit currently in use to another speech decoding circuit;
In the speech decoding switching device, a coding scheme switching section which is information on a coding scheme switching section, which is a section in which both the speech code of the received speech and the speech code of the transmission speech are input from the communication partner. Information is entered,
In the decoding operation switching process, the speech decoding switching device is configured to use the speech currently in use based on a comparison result of the comparison process in the coding system switching section indicated in the coding system switching section information. A speech decoding switching method, comprising: determining a timing suitable for switching from a decoding circuit to another speech decoding circuit, and instructing switching of the speech decoding circuit at the timing. A speech decoding switching method used for a speech decoding switching device having a plurality of types of speech decoding circuits,
The speech decoding switching device is
A process of storing the temporal transition of the level of the transmission voice in the first memory;
A process of storing the temporal transition of the received voice level in the second memory;
An analysis process for analyzing a temporal transition of the level of the transmission voice stored in the first memory and a temporal transition of the level of the reception voice stored in the second memory;
A decoding operation switching process for instructing switching from the speech decoding circuit currently in use to another speech decoding circuit;
In the speech decoding switching device, a coding scheme switching section which is information on a coding scheme switching section, which is a section in which both the speech code of the received speech and the speech code of the transmission speech are input from the communication partner. Information is entered,
In the decoding operation switching process, the speech decoding switching device is configured to use the speech currently in use based on an analysis result of the analysis process in the coding system switching section indicated in the coding system switching section information. A speech decoding switching method, comprising: determining a timing suitable for switching from a decoding circuit to another speech decoding circuit, and instructing switching of the speech decoding circuit at the timing.

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