Pulse rate estimation method, device, and system

1. A pulse rate estimation method comprising:

implementing a processor of a computer to perform:

a pulse wave signal generating step of generating a pulse wave signal from an image of a pulse rate estimation target which is supplied by a non-contact type image sensor;

a peak component suppression step of limiting an amplitude value of the pulse wave signal that is larger than a first threshold value to the first threshold value, and outputting a pulse wave analysis signal;

a frequency analysis step of outputting a frequency spectrum of the pulse wave analysis signal by using a fast Fourier transform, a plurality of bandpass filters, or a periodic signal extraction process; and

an output determination step of outputting, as a pulse rate, a frequency at which a maximum peak value is obtained when a ratio of a second largest peak value to a maximum peak value of the frequency spectrum is less than a second threshold value, otherwise a frequency displayed previously.

2. A pulse rate estimation method comprising:

implementing a processor of a computer to perform:

a pulse wave signal generating step of generating a pulse wave signal from an image of a pulse rate estimation target which is supplied by a non-contact type image sensor;

a peak component suppression step of limiting an amplitude value of the pulse wave signal that is larger than a first threshold value to the first threshold value, wherein

a feature of a waveform of the pulse wave signal is extracted, and a sample value of the pulse wave signal that has a large amplitude outside a range of the first threshold value calculated based on the feature of the waveform is replaced with the first threshold value, and outputting a pulse wave analysis signal:

a frequency analysis step of outputting a frequency spectrum of the pulse wave analysis signal by using a fast Fourier transform, a plurality of bandpass filters, or a periodic signal extraction process; and

an output determination step of outputting, as a pulse rate, a frequency at which a maximum peak value is obtained when a ratio of a second largest peak value to a maximum peak value of the frequency spectrum is less than a second threshold value, otherwise a frequency displayed previously.

3. The pulse rate estimation method of claim 2 , wherein the feature of the waveform is a standard deviation.

4. A pulse rate estimation device comprising:

implementing a processor of a computer to perform:

a pulse wave signal generation unit for generating a pulse wave signal from an image of a pulse rate estimation target which is supplied by a non-contact type image sensor;

a noise suppression unit for limiting an amplitude value of the pulse wave signal that is larger than a first threshold value to the first threshold value, and outputting a pulse wave analysis signal;

a pulse wave signal analysis unit for outputting a frequency spectrum of the pulse wave analysis signal by using a fast Fourier transform, a plurality of bandpass filters, or a periodic signal extraction process; and

an output determination unit for outputting, as a pulse rate, a frequency at which a maximum peak value is obtained when a ratio of a second largest peak value to a maximum peak value of the frequency spectrum is less than a second threshold value, otherwise a frequency displayed previously.

5. The pulse rate estimation device according to claim 4 , wherein the noise suppression unit extracts a feature of a waveform of the pulse wave signal, and replaces a sample value of the pulse wave signal that has a large amplitude outside a range of the first threshold value calculated based on the feature of the waveform with the first threshold value.

6. The pulse rate estimation device according to claim 5 , wherein the feature of the waveform is a standard deviation.

7. A pulse rate estimation system comprising:

an imaging unit for supplying the image;

the pulse rate estimation device according to claim 4 ; and

a display unit for displaying an output pulse rate.