Method and apparatus for measuring heart rate

1. A method of measuring a heart rate of a subject in an electronic device, the method comprising:

obtaining, by at least one processor of the electronic device, a face image of the subject by using the electronic device;

performing, by the at least one processor, a differential arithmetic operation between a green color component and a red color component within the face image, wherein the performing the differential arithmetic operation comprises obtaining a differential signal as a difference between a first moving average of first pixel values of the green color component and a second moving average of second pixel values of the red color component;

converting, by the at least one processor, the differential signal into a frequency signal in a frequency domain; and

determining, by the at least one processor, a heart rate of the subject based on the frequency signal,

wherein the first pixel values of the green color component are obtained as a first time series,

the second pixel values of the red color component are obtained as a second time series,

the first moving average is determined based on the first pixel values which are successive in a first section in the first time series, and

the second moving average is determined based on the second pixel values which are successive in a second section in the second time series.

2. The method of claim 1 , wherein the determining the heart rate of the subject comprises:

determining a frequency corresponding to a peak of the frequency signal to be the heart rate of the subject.

3. The method of claim 1 , further comprising recognizing, by the at least one processor, a face of the subject in an image region obtained by the electronic device.

4. The method of claim 1 , further comprising displaying on a display a message when the heart rate of the subject is not in a range which is set in advance in the electronic device.

5. The method of claim 4 , further comprising obtaining, by the at least one processor, the face image of the subject based on a user interaction to the displayed message.

6. The method of claim 1 , wherein the first section is a certain time period in the first time series, and the second section is a certain time period in the second time series.

7. The method of claim 1 , wherein the second section is a same time period as the first section.

8. The method of claim 1 , wherein the face image includes a target region determined based on a face organ of the subject, and

the differential arithmetic operation is performed based on the target region within the face image.

9. The method of claim 1 , wherein the obtaining the face image comprises obtaining the face image of the subject based on an input of the subject operating an input device.

10. The method of claim 9 , wherein the obtaining the face image further comprises determining that a face, which is present in the face image, is a face of the subject who uses the electronic device.

11. An apparatus for measuring a heart rate of a subject, the apparatus comprising:

at least one processor configured:

to obtain a face image of the subject,

to perform a differential arithmetic operation between a green color component and a red color component within the face image by obtaining a differential signal as a difference between a first moving average of first pixel values of the green color component and a second moving average of second pixel values of the red color component,

to convert the differential signal into a frequency signal in a frequency domain, and

to determine a heart rate of the subject based on the frequency signal,

wherein the first pixel values of the green color component are obtained as a first time series,

the second pixel values of the red color component are obtained as a second time series,

the first moving average is determined based on the first pixel values which are successive in a first section in the first time series, and

the second moving average is determined based on the second pixel values which are successive in a second section in the second time series.

12. The apparatus of claim 11 , wherein the at least one processor is further configured to determine a frequency corresponding to a peak of the frequency signal to be the heart rate of the subject.

13. The apparatus of claim 11 , wherein the at least one processor is further configured to control a display to display a message when the heart rate of the subject is not in a range which is set in advance in the apparatus.

14. The apparatus of claim 13 , wherein the at least one processor is further configured to obtain the face image of the subject based on a user interaction to the displayed message.

15. The apparatus of claim 11 , wherein the first section is a certain time period in the first time series, and the second section is a certain time period in the second time series.

16. The apparatus of claim 11 , wherein the second section is a same time period as the first section.

17. The apparatus of claim 11 , wherein the face image includes a target region determined based on a face organ of the subject, and

the differential arithmetic operation is performed based on the target region within the face image.

18. An apparatus for measuring a heart rate of a subject, the apparatus comprising:

at least one processor configured:

to obtain a face image of the subject,

to perform a differential arithmetic operation between a first color component and a second color component within the face image by obtaining a differential signal as a difference between a first moving average of first pixel values of the first color component and a second moving average of second pixel values of the second color component,

to convert the differential signal into a frequency signal, and

to determine a frequency corresponding to a peak of the frequency signal to correspond to a heart rate of the subject,

wherein a color of the first color component is different from a color of the second color component of RGB primary colors,

the first pixel values of the first color component are obtained as a first time series,

the second pixel values of the second color component are obtained as a second time series,

the first moving average is determined based on the first pixel values which are successive in a first section in the first time series, and

the second moving average is determined based on the second pixel values which are successive in a second section in the second time series.

19. The apparatus of claim 18 , wherein the first color component is a G component and the second color component is a color component corresponding to an average value between an R component and a B component, of the RGB primary colors.