JP2007184820A - Receiver, and method of correcting received sound signal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a call device capable of correcting the sound quality of received call with a simple configuration without needing user operation. <P>SOLUTION: The receiver includes: an operation step (step 26) for performing FFT conversion to a sound signal obtained on the basis of a received signal and obtaining a level of sound volume for every given frequency band; a storage means for storing as model information on a given model in advance the level of sound volume for every frequency band which may be owned by the sound signal obtained by receiving a signal from a transmitter of the model and a given sound quality compensation value suited to compensate the sound quality of the sound signal with respect to each model of given transmitters; and a means (step 27) for acquiring the sound quality compensation value corresponding to the sound signal on the basis of the level of the sound volume every frequency band obtained by the operation means with respect to the sound signal obtained on the basis of the received signal by referring to each model information. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a receiving apparatus that can automatically acquire a sound quality correction value that can be used for correcting sound quality of an audio signal obtained based on a received signal, and reception suitable for the receiving apparatus. The present invention relates to a method for correcting an audio signal.

  Conventionally, as a method for automatic sound quality correction in the received sound of a telephone, a method of flattening a necessary band by emphasizing a low-intensity frequency band or weakening a high-intensity frequency band is used. It has been. For example, in the received sound quality automatic correction circuit of Patent Document 1, the received signal is mixed again after passing through a linear amplifier, a low-frequency amplifier, and a high-frequency amplifier. At that time, the outputs of the low-frequency amplifier and the high-frequency amplifier are output. If the output of the low-frequency amplifier or the high-frequency amplifier is larger than a predetermined value, the output is reduced.

  Also, an equalizer device using an FFT operation is known as a technique for adjusting to a user's favorite sound quality. For example, in the equalizer device of Patent Document 2, FFT analysis is performed on an input audio signal to detect a signal level for each frequency band, and the input audio signal passes through so that the frequency level approaches a target frequency characteristic. The filter coefficient is controlled. As the target frequency characteristics, those reflecting user preferences are used based on user instructions.

Japanese Patent Laid-Open No. 10-294629 JP 2001-292491 A

  However, according to the above-described received sound quality automatic correction circuit and equalizer device, the circuit configuration is complicated. In addition, according to the equalizer device described above, the user needs to first set his / her favorite sound quality, which is troublesome for the user. In the case of reception in wireless communication, it is only necessary to correct a clear difference in sound quality so that there is no sense of incongruity, and fine correction by an equalizer is not required as in the case of listening to a musical sound or the like.

  An object of the present invention is to provide a call device capable of correcting the received sound quality with a simple configuration without requiring a user operation in view of the problems of the prior art.

  To achieve the above object, a receiving apparatus according to a first aspect of the present invention includes an arithmetic unit that performs FFT conversion on an audio signal obtained based on a received signal and obtains a volume level for each predetermined frequency band, and a predetermined transmitting apparatus. For each model, a predetermined sound quality correction value suitable for correcting the volume level for each frequency band and the sound quality of the sound signal that the sound signal obtained by receiving the signal from the transmitter of the model will have The sound quality correction value corresponding to the sound signal based on the volume level for each frequency band obtained by the computing means for the sound signal obtained based on the received signal and the storage means stored in advance as model information, Means for referring to and acquiring each model information.

  In this configuration, the receiving device corresponds to, for example, a device used for a wired or wireless communication device. For example, each predetermined frequency band corresponds to each frequency band when the audio signal is divided into three. As the sound quality correction value, for example, a correction value for a filter coefficient when the sound quality of an audio signal is corrected by a filter corresponds.

  In this configuration, the volume level for each frequency band having a ratio similar to the ratio (or distribution) of the volume levels for each predetermined frequency band obtained for the audio signal obtained based on the received signal is the model information of a certain model. If it is registered in the storage means, it can be seen that the model is the model of the transmitting device that is transmitting the received signal. Therefore, by using the sound quality correction value registered as the model information of the model, it is possible to appropriately correct the audio signal obtained based on the received signal.

  According to a second aspect of the present invention, there is provided a receiving apparatus according to the first aspect, wherein in the first aspect, the model information corresponding to the volume level for each frequency band obtained based on the received signal is present in the storage unit. When it is determined that the corresponding model information exists, a determination unit, a unit for storing the identification information of the transmission device included in the received signal in the storage unit in association with the model information, and a received signal Second identification means for determining whether or not the transmission device identification information exists in the storage means, and a model corresponding to the identification information when it is determined that the identification information of the transmission device exists Means for acquiring a sound quality correction value in the information as a sound quality correction value that can be used for sound quality correction of an audio signal obtained based on a received signal.

  In the second invention, the receiving device according to the third invention obtains the volume level for each frequency band again by the computing means when the judgment that the corresponding model information exists is not made in the second invention, and the first judging means Means for repeating the determination by the predetermined number of times, and if it is not determined that the corresponding model information exists even if the process is repeated the predetermined number of times, an audio signal obtained based on the received signal The sound quality is not corrected.

  According to a fourth aspect of the present invention, there is provided a receiving apparatus according to any one of the first to third aspects, wherein the sound quality correction value obtained for the received signal is used to correct the sound quality of the audio signal obtained based on the received signal. It is characterized by having.

  The method of correcting the received audio signal according to the fifth invention is as follows. For each model of the predetermined transmission device, for each predetermined frequency band that the audio signal obtained by receiving the signal from the transmission device of that model will have. Storing a predetermined sound quality correction value suitable for correcting the volume level of the sound signal and the sound quality of the sound signal in the storage means as model information of the model, and performing an FFT conversion on the sound signal obtained based on the received signal, A calculation step for obtaining a volume level for each frequency band, a step for determining whether or not model information corresponding to the volume level for each frequency band obtained based on a received signal exists in a storage unit, and a corresponding model When it is determined that the information exists, the identification information of the transmission device included in the received signal is stored in the storage unit in association with the model information, and in the model information Whether the quality correction value is obtained as a sound quality correction value that can be used for sound quality correction of the audio signal obtained based on the received signal, and whether the identification information of the transmission device included in the received signal exists in the storage means And when the determination is made that the identification information of the transmitting device exists, the sound quality correction value in the model information corresponding to the identification information is obtained based on the received signal. And a step of acquiring as a sound quality correction value that can be used for sound quality correction, and a step of performing sound quality correction of the audio signal obtained based on the received signal based on the acquired sound quality correction value. .

  According to the present invention, referring to the volume level and sound quality correction value for each predetermined frequency band registered in advance as model information, the received signal is based on the volume level for each frequency band of the audio signal obtained based on the received signal. Since the model of the transmitting device that transmits the sound is specified and the sound quality correction value of the sound signal is acquired, the sound quality correction of the received sound signal can be performed without requiring a user operation with a simple configuration. it can.

  Also, the identification information of the transmitting device whose model has been found is registered in association with the model information of that model, and the sound quality correction value is immediately obtained for the received audio signal from the transmitting device in which the identification information is registered. As a result, it is possible to perform sound quality correction without requiring FFT conversion for specifying a model of a transmitting apparatus that has received a signal and has model information registered therein.

  FIG. 1 is a block diagram showing a configuration of a wireless communication device according to an embodiment of the present invention. As shown in the figure, this apparatus includes a receiver 11 that performs frequency discrimination on radio waves received by an antenna, and a DSP (digital signal processor) 12 that outputs a digital audio signal based on a demodulated wave from the receiver 11. , A D / A converter 13 for converting a digital audio signal from the DSP 12 into an analog audio signal, a speaker for converting the audio signal from the D / A converter 13 into a sound wave, a CPU 15 for controlling each part of the apparatus, and a connection to the CPU 15 ROM 16 and EE-PROM 17 are provided.

  The DSP 12 performs an FFT (Fast Fourier Transform) for a predetermined time on the audio signal obtained based on the received signal, thereby dividing the audio signal into three frequency bands of a predetermined low frequency, middle frequency, and high frequency, and an average volume of each frequency frequency band. A level (hereinafter referred to as “three-divided average volume level”) can be acquired.

  The ROM 16 is provided with a model table composed of records each including items of “model name”, “three-part average volume level”, and “sound quality correction value”. That is, in each record, for each appropriate type of wireless communication device, the model name, and the three-divided average volume level that a reception signal when receiving a transmission from the wireless communication device of the model name of the model name will have. In addition, a sound quality correction value used for correcting the received sound quality is stored.

  The DSP 12 constitutes a digital filter that passes predetermined predetermined bands for the received audio signal. The CPU 15 can correct the sound quality of the received sound signal by controlling the filter coefficient of each digital filter based on the sound quality correction value corresponding to the model of the counterpart device for the received sound signal.

  The EE-PROM 17 is provided with an ID table composed of records composed of items of “ID” and “pointer”. That is, each record has an ID for identifying the wireless communication device included in the received signal for the counterpart wireless communication device that has been received in the past and whose model name is registered in the model table of the ROM 16. (Identification information) and a pointer to the record of the model name in the ROM 16 are stored.

  FIG. 2 is a flowchart showing a part of processing in the apparatus of FIG. This process is performed when there is an incoming call. When there is an incoming call, first, in step 21, processing for a call is started. That is, the received radio wave is demodulated and output of the received voice is started. Next, in step 22, it is determined whether or not the received ID (identification information) of the counterpart device exists in the ID table. The fact that the ID of the counterpart device is present in the ID table means that there has been a call with the counterpart in the past, and the sound quality correction based on the sound quality correction value corresponding to the model of the counterpart device has been made. It means that the received call was made.

  If it is determined in step 22 that the ID of the counterpart device is present in the ID table, the process proceeds to step 23, and the sound quality correction value in the record in the model table indicated by the pointer in the record of that ID is read. Next, in steps 24 and 25, based on the read sound quality correction value, the CPU 15 controls the DSP 12 to correct the sound quality of the received audio signal. Thereby, the user can perform an automatic sound quality correction call in which the sound quality is automatically corrected.

  On the other hand, if it is determined in step 22 that the ID of the counterpart device does not exist in the ID table, the process proceeds to step 26, where an FFT operation is performed on the audio signal obtained by demodulation for 5 seconds to obtain a predetermined frequency. Divide into 3 bands and find the 3 divided average volume level. Next, in step 27, it is determined whether or not a three-divided average sound volume level in which the ratio of the obtained three-divided average sound volume level and the sound volume level of each band matches is registered in the model table.

  If it is determined that it is registered, the model of the model name in the matching record of the three-part average volume level is the model of the counterpart device, and it can be specified. In this case, the process proceeds to step 28, and a new record composed of the ID of the counterpart device and a pointer to the record in the model table is registered in the ID table. Next, the process proceeds to step 24, and based on the sound quality correction value of the record in the model table, the DSP 12 is controlled in the same manner as described above to enable an automatic sound quality correction call (steps 24 and 25).

  If it is determined in step 27 that the corresponding three-divided average volume level is not registered, the process returns to step 26, and the FFT calculation in step 26 and the model table search in step 27 are performed again. If it is determined that the corresponding record exists in the model table, the process proceeds to step 28 to register the ID and the pointer (step 28), as described above, to enable the automatic sound quality correction call (step 24, 25).

  However, if the corresponding record cannot be found even after performing the FFT calculation and determination in Steps 26 and 27 three times, this is determined in Step 29, and the information about the model of the counterpart device is obtained. It is assumed that it is not registered in the model table. That is, in this case, the process proceeds to step 30 without returning to step 26, and the process for the call is continued without performing sound quality correction.

  According to the present embodiment, the model of the counterpart wireless communication device is specified with reference to the model table in the ROM 16, and the sound quality of the received sound is corrected based on the sound quality correction value in the corresponding record in the model table. As a result, it is possible to make a call with a sound quality without a sense of incongruity without requiring user operation. In addition, for the counterpart device that has made a call once and is registered in the ID table, the sound quality correction value is obtained by referring directly to the model table based on the ID table without performing the FFT calculation from the next call. Thus, it is possible to make a call with corrected sound quality.

  In addition, this invention is not limited to the above-mentioned embodiment, It can deform | transform and implement suitably. For example, in the above description, an example in which the present invention is applied to a wireless communication device has been described. Instead, the present invention may be applied to a call using IP communication. Although not particularly mentioned in the above description, the present invention is also suitable when there are relatively few models of the counterpart device that can make a call.

It is a block diagram which shows the structure of the radio | wireless telephone apparatus which concerns on one Embodiment of this invention. It is a flowchart which shows a part of process in the apparatus of FIG.

Explanation of symbols

11: Receiver, 12: DSP, 13: D / A converter, 14: Speaker, 15: CPU, 16: ROM, 17: EE-PROM.

Claims (5)

An arithmetic means for performing an FFT conversion on an audio signal obtained based on a received signal and obtaining a volume level for each predetermined frequency band;
For each model of the predetermined transmission device, a predetermined level suitable for correcting the volume level for each frequency band that the audio signal obtained by receiving the signal from the transmission device of the model and the sound quality of the audio signal will have Storage means for storing the sound quality correction value in advance as model information of the model;
Means for obtaining the sound quality correction value corresponding to the sound signal based on the volume level for each frequency band obtained by the computing means for the sound signal obtained based on the received signal with reference to each model information. And a receiving device. First determination means for determining whether or not the model information corresponding to the volume level for each frequency band obtained based on a received signal exists in the storage means;
Means for storing the identification information of the transmission device included in the received signal in the storage means in association with the model information when it is determined that the corresponding model information is present;
A second determination unit that determines whether or not the identification information of the transmission device included in the received signal exists in the storage unit;
When it is determined that the identification information of the transmission device exists, the sound quality correction value in the model information corresponding to the identification information may be used for the sound quality correction of the audio signal obtained based on the received signal. The receiving apparatus according to claim 1, further comprising a means for obtaining a sound quality correction value that can be obtained.   A means for obtaining again a volume level for each frequency band by the computing means and repeating the process of making a judgment by the first judging means a predetermined number of times when it is not judged that the corresponding model information exists; And the sound quality of the audio signal obtained based on the received signal is not corrected when it is not determined that the corresponding model information exists even after repeating the process a predetermined number of times. The receiving device according to claim 2.   The receiving apparatus according to any one of claims 1 to 3, further comprising means for correcting a sound quality of an audio signal obtained based on the sound quality correction value obtained for the received signal. . For each model of a given transmitter, suitable for correcting the volume level for each given frequency band and the sound quality of the voice signal that the audio signal obtained by receiving a signal from the transmitter of that model will have Storing the predetermined sound quality correction value in the storage means as model information of the model;
An arithmetic step of performing an FFT conversion on an audio signal obtained based on a received signal and obtaining a volume level for each frequency band;
Determining whether or not the model information corresponding to the volume level for each frequency band obtained based on a received signal exists in the storage means;
When it is determined that the corresponding model information exists, the identification information of the transmitting device included in the received signal is stored in the storage unit in association with the model information, and the sound quality correction in the model information is performed. Obtaining a value as a sound quality correction value that can be used for sound quality correction of an audio signal obtained based on a received signal;
Determining whether or not identification information of the transmission device included in the received signal exists in the storage means;
When it is determined that the identification information of the transmission device exists, the sound quality correction value in the model information corresponding to the identification information may be used for the sound quality correction of the audio signal obtained based on the received signal. Obtaining a sound quality correction value that can be obtained;
And a step of correcting the sound quality of the sound signal obtained based on the received signal based on the acquired sound quality correction value.

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