Apnea episode determination device and apnea episode determination method
First Claim
1. An apnea episode determination device comprising:
- a processor; and
a memory which stores a plurality of instructions, which when executed by the processor, cause the processor to execute,dividing a sound signal from a subject during sleep into a plurality of frames, respective frames among the plurality of frames having a preset time length;
determining whether the respective frames include a breathing sound of the subject;
detecting, based on the determining, a breathing segment and a midway segment from the respective frames, the breathing segment having respective frames including the breathing sound, the midway segment having respective frames excluding the breathing sound and the midway segment existing between the breathing segments;
calculating a time length of the midway segment by counting a number of successive respective frames excluding the breathing sound in the midway segment;
calculating an acoustic feature based on a background noise component and a signal component excluding the background noise component, which are included in the midway segment; and
determining the midway segment is an apnea episode based on the time length of the midway segment and the acoustic feature, even when the background noise component fluctuates, when the acoustic feature meets a first preset condition and the time length of the midway segment is within a preset range,wherein the acoustic feature is a signal-to-noise ratio in the midway segment calculated from one of a calculated sum, an average value and a weighted average of respective signal-to-noise ratios in the respective frames excluding the breathing sound included in the midway segment, and the first preset condition is when the signal-to-noise ratio is less than a preset threshold,thereby the apnea episode is detected more accurately regardless of the background noise.
1 Assignment
0 Petitions
Accused Products
Abstract
An apnea episode determination device includes, a processor; and a memory which stores a plurality of instructions, which when executed by the processor, cause the processor to execute, detecting a breathing segment and a midway segment from a sound signal during sleep, the breathing segment being considered to include a breathing sound, the midway segment existing in between the breathing segments; calculating an acoustic feature based on a background noise component and a signal component excluding the background noise component, which are included in the midway segment; and determining that the midway segment is an apnea episode when the acoustic feature meets a preset condition.
13 Citations
13 Claims
-
1. An apnea episode determination device comprising:
-
a processor; and a memory which stores a plurality of instructions, which when executed by the processor, cause the processor to execute, dividing a sound signal from a subject during sleep into a plurality of frames, respective frames among the plurality of frames having a preset time length; determining whether the respective frames include a breathing sound of the subject; detecting, based on the determining, a breathing segment and a midway segment from the respective frames, the breathing segment having respective frames including the breathing sound, the midway segment having respective frames excluding the breathing sound and the midway segment existing between the breathing segments; calculating a time length of the midway segment by counting a number of successive respective frames excluding the breathing sound in the midway segment; calculating an acoustic feature based on a background noise component and a signal component excluding the background noise component, which are included in the midway segment; and determining the midway segment is an apnea episode based on the time length of the midway segment and the acoustic feature, even when the background noise component fluctuates, when the acoustic feature meets a first preset condition and the time length of the midway segment is within a preset range, wherein the acoustic feature is a signal-to-noise ratio in the midway segment calculated from one of a calculated sum, an average value and a weighted average of respective signal-to-noise ratios in the respective frames excluding the breathing sound included in the midway segment, and the first preset condition is when the signal-to-noise ratio is less than a preset threshold, thereby the apnea episode is detected more accurately regardless of the background noise. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. An apnea episode determination method comprising:
-
dividing a sound signal from a subject during sleep into a plurality of frames, respective frames among the plurality of frames having a preset time length; determining whether the respective frames include a breathing sound of the subject; detecting, based on the determining, a breathing segment and a midway segment from the respective frames, the breathing segment having respective frames including the breathing sound, the midway segment having respective frames excluding the breathing sound and the midway segment existing between the breathing segments; calculating a time length of the midway segment by counting a number of successive respective frames excluding the breathing sound in the midway segment; calculating, by a computer processor, an acoustic feature based on a background noise component and a signal component excluding the background noise component, which are included in the midway segment; and determining the midway segment is an apnea episode based on the time length of the midway segment and the acoustic feature, even when the background noise component fluctuates, when the acoustic feature meets a first preset condition and the time length of the midway segment is within a preset range, wherein the acoustic feature is a signal-to-noise ratio in the midway segment, calculated from one of a calculated sum, an average value and a weighted average of respective signal-to-noise ratios in the respective frames excluding the breathing sound included in the midway segment and the first preset condition is when the signal-to-noise ratio is less than a preset threshold, thereby the apnea episode is detected more accurately regardless of the background noise.
-
-
12. An apnea episode determination device comprising:
-
a processor; and a memory which stores a plurality of instructions, which when executed by the processor, cause the processor to execute, dividing a sound signal from a subject during sleep into a plurality of frames, respective frames among the plurality of frames having a preset time length; determining whether the respective frames include a breathing sound of the subject; detecting, based on the determining, a breathing segment and a midway segment from the respective frames, the breathing segment having respective frames including the breathing sound, the midway segment having respective frames excluding the breathing sound and the midway segment existing between the breathing segments; calculating a time length of the midway segment by counting a number of successive respective frames excluding the breathing sound in the midway segment; calculating an acoustic feature based on a background noise component and a signal component excluding the background noise component, which are included in the midway segment; and determining the midway segment is an apnea episode based on the time length of the midway segment, the acoustic feature and a correlation between the sound signal in the midway segment and at least one of the sound signals in the breathing segments immediately before and immediately after the midway segment, even when the background noise component fluctuates, when the acoustic feature meets a first preset condition and the time length of the midway segment is within a preset range, wherein the first preset condition is when the correlation is less than a preset threshold, wherein the acoustic feature is a signal-to-noise ratio in the midway segment calculated from one of a calculated sum, an average value and a weighted average of respective signal-to-noise ratios in the respective frames excluding the breathing sound included in the midway segment, and the first preset condition is when the signal-to-noise ratio is less than a preset threshold, thereby the apnea episode is detected more accurately regardless of the background noise. - View Dependent Claims (13)
-
Specification