JPS6329757B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention provides a device that commands the operation of a load corresponding to a voice command by recognizing voice commands based on registered voice data of an operator registered in advance. The present invention relates to a voice recognition device for a vehicle that can reliably recognize voice commands by instructing the operation of a voice command. Conventionally, as this type of speech recognition device, there is one shown in FIG. 1, for example. In FIG. 1, 1 is a microphone installed near the driver's seat. When using the voice recognition device, first register a predetermined voice command by the operator's voice by operating a registration switch 2. . That is, when the registration switch 2 is turned on, the switch input detection circuit 4 detects the switch operation and produces an output on the signal line 4a, and the control section 5 gives a registration mode processing command to each circuit section. In such a registration mode, a predetermined voice command, for example, a voice command "radio" specified for turning on a car radio, is transmitted to the microphone 1.
When the voice command is issued to the user, the microphone 1 converts the voice command into an electric signal, which is amplified by the voice input circuit 6. This amplified output signal is input to the voice detection circuit 7, and the start point of the voice signal becomes a time-series signal. It is detected based on the rise change in the signal level, and the control unit 5
command to start the registration process. Therefore, the audio signal from the microphone 1 is divided into predetermined frequencies by the band filter group 8, and squared or rectified to obtain the audio power spectrum in each frequency band in the parameter extractor 9, which becomes audio power information. The data is digitally converted into time-series audio data and stored in the memory 10. At this time, since the registration mode is set by operating the registration switch 2, the voice data in the memory 10 is transferred to the registration data storage section 11 and registered as reference data for performing voice recognition processing. Next, after registering the voice command, if you want to listen to the on-vehicle load, for example, the radio, turn on the command start switch 3 to give the predetermined voice command "radio" to the microphone 1. . In response to this ON operation of the command start switch 3, the switch input detection circuit 4 generates an output on the signal line 4b, and the control section 5 gives a recognition mode control command to each circuit section. The voice commands input from 1 are converted into voice data and written into the memory 10 in the same way as at the time of registration. The audio data stored in this memory 10 is
A similarity comparison processing section 12 calculates the degree of similarity between a plurality of registered data sequentially read out from the registered data storage section 11. To calculate this degree of similarity, after normalizing the time axis and normalizing the level of the audio data and the registered data, the degree of similarity is determined by performing calculations on Tievishiev distance and other distances. Become. The similarity value calculated by the similarity comparison processing section 12 is judged by the recognition word processing judgment section 13 as to whether or not the similarity value is within a predetermined threshold range.
When it is within the range, a command corresponding to the audio data having this degree of similarity is output to the drive unit 14, and the car radio is turned on. By the way, the environment in which a voice recognition device for a vehicle is used has a higher ambient noise level than that of a general voice recognition device.In particular, when the vehicle is in use with the engine started, the noise level in the passenger compartment rises, and noise is mixed in. Since these occur randomly, when a voice command is given to operate a load, there is a high proportion of noise components in the voice signal, and if a relatively large amount of noise is mixed in, the voice command may not be recognized or even worse. There was a risk that the incorrect recognition would command the operation of the wrong load. The present invention has been made by focusing on such conventional problems, and recognizes the voice command inputted following the ON operation of the command start switch based on registered voice data, and based on the recognition output, the above-mentioned voice command is recognized. In a device that commands the operation of a load in response to a voice command,
In order to ensure recognition of voice commands, the above problem is solved by instructing the operation of the load corresponding to the voice command only when it is determined that two voice commands input sequentially are the same. It is intended to. Hereinafter, the present invention will be explained based on the drawings. FIG. 2 is a block diagram showing one embodiment of the present invention. First, to explain the configuration, a registration switch 2, a command start switch 3, a switch input detection circuit 4, a control unit 5, and audio from a band filter group 8 (not shown) that divides an audio signal from a microphone into frequency bands. A parameter extraction circuit 9 that extracts features in the power spectrum of each frequency band of the signal and converts it into predetermined time series data.
The circuit section consisting of is the same as the conventional device shown in FIG. In addition, in the present invention, a multiplexer 20 controlled by the control unit 5 is provided at the output of the parameter extraction circuit 9, and the output of the multiplexer 20 receives audio data F ₁ based on the first audio command.
A memory 10a that stores (X) and a memory 1 that stores voice data F ₂ (X) of the second voice command.
0b is provided. In addition, the registration data storage section 11 includes a registration switch 2.
Registration data F ₀ (X) is stored in advance, which is obtained by converting a predetermined voice command issued by the operator into time-series data in the registration mode by the ON operation. The registration data stored in the registration data storage section 11 is as shown in Table 1 below, for example.

【table】

[Table] The meaning of the registration data shown in Table 1 is as follows, taking radio as an example. However, the time series data is configured such that the number of filter stages is i=1 to 4 and the number of time series data is j=1 to 32. Note that the above time series data is based on an example in which the number of filter stages in the band filter group 8 is four. The similarity comparison processing unit 12 calculates the degree of similarity for speech recognition, and the calculation of the Tievishiev distance or the like is used to calculate the degree of similarity. For this similarity calculation, similarity calculation units 120a, 120
b is provided, and the similarity calculator 120a is connected to the memory 1.
0a storage data F ₁ (X) and registered data storage unit 1
The similarity between registered data F ₀ (X) of 1 is expressed as l ₁ (X) = | F ₀ (X) − F ₁ (X) | = | ₄ 〓 ⁱ⁼¹ ₃₂ 〓 ^j=1 f ^O _X (i, j) − ₄ 〓 ⁱ⁼¹ _{32 〓} ^j=1 f ¹
Further, the similarity calculator 120b is connected to the memories 10a and 10.
The similarity between the audio data F ₁ (X) and F ₂ (X) of b is expressed as l ₂ (X)=｜F ₁ (X)−F ₂ (X)｜= ₄ 〓 ⁱ⁼¹ ₃₂ 〓 ^j=1 f ¹ _X (i, j ⁾ − ₄ 〓 ⁱ⁼¹ ₃₂ 〓 ^{j=1 f} ₂ A minimum value discriminator 122 is provided at the output of the similarity calculator 120a to determine and output the minimum similarity among the plurality of similarity values calculated by the similarity calculator 120a. ing. The recognition word judgment processing section 13 includes the similarity comparison processing section 1
It has a function of determining whether the similarity calculated in step 2 is within a predetermined threshold range and outputting a command to operate the load corresponding to the voice command when it is within the threshold range. The threshold value h ₁ stored in the threshold value memory 132 a is compared with the minimum similarity value extracted by the minimum value discriminator 122 by the device 130 a, and the comparison result is provided to the discriminator 134 .
Further, the comparator 130b is set with a threshold value _h2 stored in the threshold value memory 132b as a reference value, and the similarity calculated by the similarity calculator 120b is compared and determined using this threshold value _h2 , and the result is provided to the discriminator 134. ing.
Furthermore, when the comparator 130a obtains a degree of similarity that is less than or equal to the threshold value _h1 , the discriminator 134 instructs the display 18 to display a request for inputting a second voice command, and also instructs the control unit 5 to display a request for inputting a second voice command. For multiplexer 20
A command is given to switch the memory 10b to the memory 10b side. or,
After the second voice command is input, the comparator 130
When it is determined that the degree of similarity is equal to or less than the threshold value _h2 in b, a signal is sent to the control unit 5 to instruct the operation of the load corresponding to the voice command. Furthermore, in the embodiment shown in FIG. 2, the output of a vehicle state detection circuit 15 is supplied to the control unit 5, and this vehicle state detection circuit 15 has an ignition switch which has a contact that closes when the ignition switch is turned on. The output of the relay 16 and the alternator output are provided, and when the output of the ignition relay 16 is turned on and the alternator output are obtained, it is detected that the vehicle is in use and is output. Sometimes it detects that the vehicle is stopped and outputs an output. This vehicle state detection circuit 15
The function is to detect an increase in the cabin noise level when the vehicle is being used, that is, when the engine is started, and to notify the controller 5 of this fact. During detection, the same voice command is input twice to command recognition mode control for recognition processing. Next, the operation of the embodiment shown in FIG. 2 will be explained with reference to the operational flow shown in FIG. Now, suppose that the operator issues a predetermined voice command by turning on the command start switch 3 while the vehicle state detection circuit 15 is detecting and outputting the usage state of the vehicle. The output of the switch input detection circuit 4 caused by the ON operation of the command start switch 3 causes the control unit 5 to enter a recognition mode in which the same voice command is input twice and recognized, and first switches the multiplexer 20 to the memory 10a side and blocks B. Wait for voice command input as shown in . Next, if a predetermined voice command is input via the microphone,
The voice signal based on this voice command is frequency-divided by a group of band filters 8 and is converted into time-series data corresponding to the power spectrum of each frequency band in a parameter extraction circuit 9. When converting this time-series data, The audio data is subjected to time axis normalization, level normalization, etc., and is stored in the memory 10a via the multiplexer 20.
It is stored as F ₁ (X). Memory 1 like this
When the first audio data is stored in 0a, the similarity calculation unit 120a of the similarity comparison processing unit 12 stores the first audio data as shown in block D.
F ₁ (X) and registration data F ₀ in the registration data storage section 11
(X) is calculated by the above equation (1), and the minimum one is determined from among the plurality of calculated similarities l ₁ (X) as shown in block E. It is applied to the comparator 130a of the recognition word judgment processing section 13. The comparator 130a performs a comparison with the threshold value h1 of the threshold value memory 132a, as shown in the discrimination block F, and when the minimum similarity _l1 ( _X ) is less than the threshold value _h1 , the discriminator 134 makes a comparison as shown in the block G. A message is displayed on the display 18 requesting input of a second voice command. At the same time, the discriminator 134 gives a control command to the control unit 5 to switch the multiplexer 20 to the memory 10b side. Therefore, the operator
If the same voice command is issued in response to the second voice command request display, the voice data similarly converted to time series data by the parameter extraction circuit 9 is stored in the memory 10b via the multiplexer 20 as voice data _F2. (X). Next, as shown in block I, the similarity calculation unit 120b of the similarity comparison processing unit 12 calculates the audio data F ₁ stored in the memories 10a and 10b.
A calculation of the degree of similarity l ₂ (X) between (X) and F ₂ (X) is performed based on the above-mentioned equation (2), and is provided to the comparator 130b. In the comparator 130b, the discrimination block J
As shown in FIG. 3, a comparison is made between the threshold h ₂ of the threshold memory 132b and the similarity l ₂ (X), and when the similarity is less than the threshold h ₂ , the discriminator 134 selects the load that has been recognized in blocks C to F. operating command,
That is, as shown in block K, an operation command corresponding to X is given to the control section 5, and the control section 5 operates a drive section (not shown) to operate the load in accordance with the voice command. This ends the recognition. On the other hand, in discrimination blocks F and J, the similarity l ₁
(X) or l ₂ (X) exceeds the threshold h ₁ or h ₂ , the process proceeds to block L, where a request for re-input is displayed on the display 18, and the Return to the state of waiting for the first voice command.
Note that a relationship such as h ₁ > h ₂ is defined between the threshold values h ₁ and h ₂ in the recognition word judgment processing unit 13, and 1
The threshold for determining the similarity between the second voice command and the second voice command is made stricter, and if the proportion of noise components included in the first voice command and the second voice command is significantly different, , since there is a risk of misrecognition due to the mixing of noise components, in this case the threshold
On the condition that _h2 is exceeded, the voice command is restarted without activating the load due to recognition of the voice command, and the erroneous activation of the load due to erroneous recognition of the voice command is reliably prevented. There is. In this way, in the above embodiment, the same voice command can be
This system prevents erroneous recognition of voice commands by inputting multiple times, so if a malfunction occurs while driving, for example,
This makes it possible to turn on and off an ignition switch or turn on and off a light, which can be difficult to do, by voice commands. In the embodiment shown in FIG. 2, voice recognition is performed between the first voice command and the registered data,
Regarding the second voice command, the degree of similarity with the first voice command is determined, and on the condition that the voice commands are the same, the system issues a command to operate the load corresponding to the first recognized voice command. However, as another example, voice recognition is performed based on registered data for each of the first and second voice commands, and only when both recognition outputs match, the load corresponding to this voice command is It may also be possible to instruct the operation of. Furthermore, in the above embodiment, when the running state of the vehicle is detected, the voice command is input twice to perform the recognition process, but regardless of whether the vehicle is running or stopped, all A recognition process may be performed in which a voice command is input twice regarding the vehicle state. As explained above, according to the present invention, the voice command inputted following the ON operation of the command start switch is recognized based on registered voice data stored in advance, and the voice command is responded to based on the recognition output. the device for instructing the operation of a load, which recognizes at least one of two identical voice commands input sequentially based on the voice registration data, and determines that the two voice commands are the same; Since the load operation corresponding to this voice command is commanded only at certain times, even if a predetermined voice command is given in a state where the noise level in the vehicle interior is high, such as when the car is running, it will not be possible to operate the load based on the two voice commands that are executed sequentially. Even if noise is mixed in with the voice command, it is possible to reliably prevent the voice command from being misrecognized due to this noise component. Important operational items such as turning on and off switches and turning on and off lights can also be operated by voice commands, resulting in the effect that the reliability of the voice recognition device can be greatly improved.

[Brief explanation of the drawing]

Figure 1 is a block diagram showing an example of a conventional device.
FIG. 2 is a block diagram showing an embodiment of the present invention.
FIG. 3 is an operational flow diagram of the embodiment of FIG. 2. 1...Microphone, 2...Registration switch, 3
...Command start switch, 4...Switch input detection circuit, 5...Control unit, 6...Audio input circuit, 7...
...Audio detection circuit, 8...Band filter group, 9...
Parameter extraction circuit, 10, 10a, 10b...
Memory, 12... Similarity comparison processing section, 13... Recognized word judgment processing section, 14... Drive section, 15... Vehicle state detection circuit, 16... Ignition relay,
18...Display device, 20...Multiplexer, 11
...Registered data storage section, 120a, 120b...
Similarity calculator, 122... Minimum value discriminator, 130
a, 130b... comparator, 132a, 132b...
...Threshold value memory, 134...Discriminator.

Claims (1)

[Scope of Claims] 1. Recognizes a voice command input following the ON operation of a command start switch based on registered voice data,
In a device that commands the operation of a load corresponding to a voice command based on the recognition output, at least one voice command among at least two voice commands input sequentially is recognized based on the registered voice data, and , a voice for a vehicle, characterized in that a recognition means is provided that instructs the operation of a load corresponding to the voice command only when it is determined that the similarity of each voice command input sequentially is within a predetermined range. recognition device. 2. The recognition means includes a storage unit that stores each of voice data based on the first voice command and voice data based on the second voice command, and a plurality of registered voice data and the first voice data stored in the storage unit. a recognition calculation unit that calculates the degree of similarity with the voice data and recognizes the first voice data based on the degree of similarity that is equal to or less than a predetermined threshold; and the first and second voice data stored in the storage unit.
an output command unit that calculates the degree of similarity of the second voice data, and when the degree of similarity is less than a predetermined threshold value, determines that the voice commands are the same and instructs the operation of the load based on the recognition output of the recognition calculation unit; A voice recognition device for a vehicle according to claim 1.