Method and system for speech detection
A system and method for determining an amount of speech in an audio signal may include for example: obtaining segments of the audio signal, wherein the segments are grouped into blocks; for each one of the segments, calculating a segment value indicative of an amplitude of the audio signal of a respective segment; for each one of the blocks calculating a block value indicative of the amplitude of the audio signal of a respective block; and calculating an audio signal speech grade based on segment values and block values, wherein the audio signal speech grade is indicative of the amount of speech in the audio signal.
1. A computer implemented method for determining an amount of speech in an audio signal, the method comprising:
obtaining the audio signal, the audio signal having an amplitude indicative of a volume level of sound;
for each one of a plurality of segments of the audio signal, wherein the segments are grouped into blocks, calculating, by a processor, a segment value indicative of an amplitude of the audio signal of the segment;
for each one of the blocks calculating, by the processor, a block value indicative of the amplitude of the audio signal of the block, wherein the block value is based on the segment values within the block;
calculating, by the processor, an audio signal speech grade based on the segment values′ relationship to values derived from the block values, wherein the audio signal speech grade is indicative of the amount of speech in the audio signal;
determining, by the processor, whether the audio signal contains speech based on the audio signal speech grade; and
only if the audio signal contains speech, performing one of: transcription of the audio signal by the processor; real time word detection on the audio signal by the processor; emotion analysis on the audio signal by the processor; and compression of the audio signal by the processor.
2. The method of claim 1 , wherein the length of each of the segments is in a range of 5-40 milliseconds and wherein the size of each of the blocks is in the range of 40-60segments.
3. The method of claim 1 , wherein
calculating the segment value comprises averaging an absolute value of the audio signal of the respective segment and calculating the block value comprises averaging the segment values of segments associated with the respective block.
4. The method of claim 1 , wherein calculating the audio signal speech grade comprises:
calculating block speech grades by:
determining an upper detection boundary and a lower detection boundary relative to the block value;
counting a number of segments that have segment value that is above the upper detection boundary (HighSegments);
counting a number of segments that have segment value that is below the lower detection boundary (LowSegments);
calculating an activity ratio by:
activity
ratio
=
LowSegments
+
HighSegments
total
amount
of
segments
in
the
block
;
and
calculating
a
division
ratio
by
:
Division
ratio
=
1
-
HighSegments
-
LowSegments
HighSegments
+
LowSegments
;
wherein the block speech grade of a block is proportional to the activity ratio times the division ratio of the respective block; and,
calculating the audio signal speech grade by averaging the block speech grades.
5. The method of claim 4 , comprising:
assigning a marker to the audio signal if a block speech grade of at least one block of the audio signal is above a predetermined threshold.
6. The method of claim 5 , wherein the marker is a predetermined minimum value given to the audio signal speech grade.
7. The method of claim 1 , comprising performing at least one of:
providing an alarm if for a predetermined amount of time of the audio signal speech grade is lower than a predetermined minimum; and
providing reports regarding the audio signal speech grade over time.
8. The method of claim 1 , comprising:
monitoring the performance of a recording system based on the audio signal speech grade.
9. The method of claim 1 , wherein the method for determining the amount of speech in the audio signal is performed in real-time.
10. The method of claim 1 , comprising:
storing the audio signal in a file system only if the audio signal contains speech.
11. The method of claim 1 , comprising:
monitoring health of a recording system based on the audio signal speech grade, and visualizing the health of the recording system.
12. A device for determining an amount of speech in an audio signal, the device comprising:
a memory; and
a processor configured to:
for each one of a plurality of segments of the audio signal, wherein the segments are grouped into blocks, calculate a segment value indicative of an amplitude of the audio signal of the segment;
for each one of the blocks calculate a block value indicative of the amplitude of the audio signal of the block, wherein the block value is based on the segment values within the block;
calculate an audio signal speech grade based on the segment values′ relationship to values derived from the block values, wherein the audio signal speech grade is indicative of the amount of speech in the audio signal;
determine, whether the audio signal contains speech based on the audio signal speech grade; and
only if the audio signal contains speech, perform one of: transcription of the audio signal; real time word detection on the audio signal; emotion analysis on the audio signal; and compression of the audio signal.
13. The device of claim 12 , wherein the length of each of the segments is in a range of 5-40 milliseconds, and wherein the size of each of the blocks is in the range of 40-60 segments.
14. The device of claim 12 , wherein the processor is configured to calculate the segment value by averaging an absolute value of the audio signal of the respective segment and to calculate the block value by averaging the segment values of segments associated with the respective block.
15. The device of claim 12 , wherein the processor is configured to calculate the audio signal speech grade by:
calculating block speech grades by:
determining an upper detection boundary and a lower detection boundary relative to the block value;
counting a number of segments that have segment value that is above the upper detection boundary (HighSegments);
counting a number of segments that have segment value that is below the lower detection boundary (LowSegments);
calculating an activity ratio by:
activity
ratio
=
LowSegments
+
HighSegments
total
amount
of
segments
in
the
block
;
and
calculating
a
division
ratio
by
:
Division
ratio
=
1
-
HighSegments
-
LowSegments
HighSegments
+
LowSegments
;
wherein the block speech grade of a block is proportional to the activity ratio times the division ratio of the respective block; and,
calculating the audio signal speech grade by averaging the block speech grades.
16. The device of claim 15 , wherein the processor is configured to:
assign a predetermined minimum value to the audio signal speech grade if a block speech grade of at least one block of the audio signal is above a predetermined threshold.
17. The device of claim 12 , comprising:
a storage device;
wherein the processor is configured to:
determine whether to store the audio signal in the storage device based on the audio signal speech grade.
18. The device of claim 12 , comprising:
a recording module configured to record a plurality of audio signals from a plurality of channels;
wherein the processor is configured to:
calculate an audio signal speech grade for each of the plurality of audio signals of the plurality of channels; and
monitor the performance of the recording system based on the audio signal speech grades.
19. The device of claim 10 , wherein the processor is configured to determine the amount of speech in the audio signal in real-time.
20. The device of claim 10 , comprising:
a first recording module configured to record a plurality of audio signals of a plurality of calls from a plurality of channels;
a second recording module configured to record the same audio signals;
wherein the processor is configured to:
calculate an audio signal speech grade for each of the plurality of audio signals of the plurality of channels for each of the recording modules; and
compare the speech grades of audio signals of the same calls as recorded by the first and the second recording modules; and
monitor the performance of the recording modules based on the comparison.
21. A non-transitory storage medium having stored thereon instructions that, when executed by a processor, cause the processor to perform a method comprising:
for each one of a plurality of segments of the audio signal, wherein the segments are grouped into blocks, calculating a segment value indicative of an amplitude of the audio signal of the segment;
for each one of the blocks calculating a block value indicative of the amplitude of the audio signal of the block, wherein the block value is based on the segment values within the block;
calculating an audio signal speech grade based on the segment values′ relationship to values derived from the block values, wherein the audio signal speech grade is indicative of the amount of speech in the audio signal;
determining, by the processor, whether the audio signal contains speech based on the audio signal speech grade; and
only if the audio signal contains speech, performing one of: transcription of the audio signal by the processor; real time word detection on the audio signal by the processor; emotion analysis on the audio signal by the processor; and compression of the audio signal by the processor.
22. The non-transitory storage medium of claim 21 , wherein calculating the audio signal speech grade comprises:
calculating block speech grades by:
determining an upper detection boundary and a lower detection boundary relative to the block value;
counting a number of segments, HighSegments, that have segment value that is above the upper detection boundary;
counting a number of segments, LowSegments, that have segment value that is below the lower detection boundary;
calculating an activity ratio by:
activity
ratio
=
LowSegments
+
HighSegments
total
amount
of
segments
in
the
block
;
and calculating a division ratio by:
Division
ratio
=
1
-
HighSegments
-
LowSegments
HighSegments
+
LowSegments
;
wherein the block speech grade of a block is proportional to the activity ratio times the division ratio of the respective block; and
calculating the audio signal speech grade by averaging the block speech grades.