Apparatus and method for voice activity detection
First Claim
1. A voice activity decision apparatus comprising:
- a processor in communication with a memory, wherein the processor is configured to receive an input signal;
an autocorrelation calculation module stored in the memory and executable with the processor, the autocorrelation calculation module configured to calculate a plurality of autocorrelation values for the input signal, the plurality of autocorrelation values calculated within a predetermined interval;
a delay calculation module stored in the memory and executable with the processor, the delay calculation module configured to receive the autocorrelation values calculated within the predetermined interval by the autocorrelation calculation module, and further configured to identify local maximum valued autocorrelation values within the autocorrelation values, and the delay calculation module further configured to calculate a plurality of delays within the predetermined interval, wherein the delays comprise a respective delay for each of the local maximum valued autocorrelation values;
a noise decision module stored in the memory and executable with the processor, the noise decision module configured to receive the delays, the noise decision module further configured to determine whether variations between the received delays are less than a threshold for at least a predetermined period of time, and further configured to generate a signal characteristic determination that the input signal includes a non-noise portion based upon determination that the variations between the received delays are less than the threshold for the at least the predetermined period of time;
an activity detector module stored in the memory and executable with the processor, the activity detector module configured to receive the signal characteristic determination of the input signal, and further configured to determine a signal activity decision based on the signal characteristic determination; and
a noise estimation module stored in the memory and executable with the processor, the noise estimation module configured to receive the input signal and generate a noise estimate for the input signal,wherein the activity detector module is further configured to determine the signal activity decision based on the signal characteristic determination, the input signal, and the noise estimate, and the noise estimation module is further configured to adapt the noise estimate based on the signal activity decision.
1 Assignment
0 Petitions
Accused Products
Abstract
It is provided a voice activity decision apparatus capable of accurately performing the decision on the state being associated with a sound interval or a silence interval also in terms of the input signal having many aperiodic components and/or plural mixed different periodic components. The apparatus 1 comprises: an autocorrelation calculating unit 11 for calculating autocorrelation values of an input signal; a delay calculating unit 12 for calculating plural delays at which autocorrelation values calculated by the autocorrelation calculating unit 11 become maximums; a noise deciding unit 13 for deciding whether the input signal is a noise or not based on the plurality of delays calculated by the delay calculating unit 12; and an activity decision unit 14 for performing the activity decision in terms of the input signal based on results of decision by the noise deciding unit 13 and the input signal.
43 Citations
34 Claims
-
1. A voice activity decision apparatus comprising:
-
a processor in communication with a memory, wherein the processor is configured to receive an input signal; an autocorrelation calculation module stored in the memory and executable with the processor, the autocorrelation calculation module configured to calculate a plurality of autocorrelation values for the input signal, the plurality of autocorrelation values calculated within a predetermined interval; a delay calculation module stored in the memory and executable with the processor, the delay calculation module configured to receive the autocorrelation values calculated within the predetermined interval by the autocorrelation calculation module, and further configured to identify local maximum valued autocorrelation values within the autocorrelation values, and the delay calculation module further configured to calculate a plurality of delays within the predetermined interval, wherein the delays comprise a respective delay for each of the local maximum valued autocorrelation values; a noise decision module stored in the memory and executable with the processor, the noise decision module configured to receive the delays, the noise decision module further configured to determine whether variations between the received delays are less than a threshold for at least a predetermined period of time, and further configured to generate a signal characteristic determination that the input signal includes a non-noise portion based upon determination that the variations between the received delays are less than the threshold for the at least the predetermined period of time; an activity detector module stored in the memory and executable with the processor, the activity detector module configured to receive the signal characteristic determination of the input signal, and further configured to determine a signal activity decision based on the signal characteristic determination; and a noise estimation module stored in the memory and executable with the processor, the noise estimation module configured to receive the input signal and generate a noise estimate for the input signal, wherein the activity detector module is further configured to determine the signal activity decision based on the signal characteristic determination, the input signal, and the noise estimate, and the noise estimation module is further configured to adapt the noise estimate based on the signal activity decision. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
-
-
14. A non-transitory computer readable storage device for storing a voice activity detection program, the computer readable storage device comprising:
-
computer program code embodied on said computer readable storage device, wherein the computer program code is executable with a processor, and wherein the computer program code comprises; computer program code to calculate a plurality of autocorrelation values of an input signal within a predetermined interval; computer program code to identify local maximum autocorrelation values within the autocorrelation values calculated within the predetermined interval; computer program code to calculate a delay for each of the local maximum autocorrelation values identified within the predetermined interval to generate a plurality of delays associated with the local maximum autocorrelations values; computer program code to determine whether variations between the delays associated with the local maximum autocorrelation values are less than a threshold for a predetermined period of time; computer program code to, in response to determination that the variations between the delays associated with the local maximum autocorrelation values are less than the threshold for the predetermined period of time, generate a signal characteristic determination that the input signal includes a signal component other than noise; computer program code to determine a signal activity decision based on the signal characteristic determination;
computer program code to generate a noise estimate, wherein the computer program code to determine the signal activity decision further comprises computer program code to generate the signal activity decision based on the input signal and the noise estimate; andcomputer program code to adapt the noise estimate in response to the signal activity decision. - View Dependent Claims (15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26)
-
-
27. A method for voice activity detection comprising:
-
calculating with a processor a plurality of autocorrelation values of an input signal, the autocorrelation values calculated within a predetermined interval; identifying local maximum autocorrelation values within the autocorrelation values calculated within the predetermined interval with the processor; calculating a delay for each of the local maximum autocorrelation values identified within the predetermined interval with the processor; generating a plurality of delays associated with the local maximum autocorrelations values with the processor; determining with the processor whether variations between the delays associated with the local maximum autocorrelation values are less than a threshold for a predetermined period of time; generating an input signal characteristic determination of the input signal with the processor when determination that the variations between the delays associated with the local maximum autocorrelation values are less than the threshold for the predetermined period of time, the input signal characteristic determination indicative that the input signal includes a signal component other than noise; generating a noise estimate of the input signal with the processor; the processor adapting the noise estimate based on a previous signal activity decision; and the processor determining a signal activity decision based on the input signal characteristic determination and consideration of the noise estimate of the input signal. - View Dependent Claims (28, 29, 30, 31, 32, 33, 34)
-
Specification