Method and Apparatus to Facilitate Using Visible Light Images to Determine a Heart Rate

• US 20090226071A1
• Filed: 03/06/2008
• Published: 09/10/2009
• Est. Priority Date: 03/06/2008
• Status: Abandoned Application

• Current Assignee: Motorola Mobility, Inc. (Lenovo Group Ltd.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Biancullli, Thomas D., Schuler, Francesca, Cholewczynski, Mark W., Jonnalagadda, Krishna, Ahmed, Mohamed I.
• Application Number:
  US12/043,515
• Publication Number:
  US 20090226071A1
• Time in Patent Office: Days
• US Class Current: 382/133
• CPC Class Codes: A61B 2576/00 Medical imaging apparatus involving image processing or analysis A61B1/00009, A61B6/52 and A61B8/52 take precedence; image processing per se G06T; details of algorithms for analysing medical images G06T7/0012
• CPC Class Codes: A61B 5/0013 Medical image data A61B1/00011, A61B6/56, A61B8/56 take precedence
• CPC Class Codes: A61B 5/02416 using photoplethysmograph signals, e.g. generated by infrared radiation A61B5/14552 takes precedence
• CPC Class Codes: A61B 5/02438 with portable devices, e.g. worn by the patient
• CPC Class Codes: A61B 5/6898 Portable consumer electronic devices, e.g. music players, telephones, tablet computers
• CPC Class Codes: G06V 40/1388 using image processing
• CPC Class Codes: G16H 30/40 for processing medical images, e.g. editing

Abstract

An apparatus (400) can receive (101) a plurality of visible light images as correspond to a subject'"'"'s skin (403) proximal to a blood-transporting capillary (404) and then process (102) that plurality of visible light images to thereby determine a heart rate for the subject. These teachings will accommodate both light-transmissive images and light-reflective images. By one approach, these visible light images can comprise images that are captured by use of a cellular telephone camera (402). The aforementioned processing can occur, in whole or in part, at the cellular telephone or at a remotely located server (408).

Claims

1. A method comprising:

at an apparatus;

receiving a plurality of visible light images as correspond to a subject'"'"'s skin proximal to a blood-transporting capillary;

processing the plurality of visible light images to thereby determine a heart rate for the subject.

2. The method of claim 1 wherein the plurality of visible light images comprise at least one of:

light-transmissive images;

light-reflective images.

3. The method of claim 1 wherein the plurality of visible light images comprise images having corresponding color components and wherein processing the plurality of visible light images comprises, at least in part:

processing the plurality of visible light images to transform the corresponding color components into different color components.

4. The method of claim 3 wherein processing the plurality of visible light images to transform the corresponding color components into different color components comprises providing corresponding images of hue saturation value (HSV) components;

and wherein processing the plurality of images further comprises processing the corresponding images of hue saturation value (HSV) components to provide corresponding high contrast images.

5. The method of claim 3 wherein processing the plurality of visible light images further comprises, at least in part:

reducing dimensional content of the corresponding high contrast images to provide corresponding reduced-dimensionality images.

6. The method of claim 5 wherein reducing dimensional content of the corresponding high contrast images comprises at least one of:

reducing dimensional content of the corresponding high contrast images by selecting and using only one image component from amongst a plurality of image components as comprise the corresponding high contrast images;

when the corresponding high contrast images comprise red green blue (RGB) color model images, processing red green and blue component values as a function of √

{square root over ((R²+G²+B²))};

reducing dimensional content of the corresponding reduced-dimensionality images by converting the plurality of visible light images to a plurality of corresponding binary images.

7. The method of claim 6 wherein selecting and using only one image component comprises selecting and using only value components of hue saturation value (HSV) image components as comprise the plurality of image components.

8. The method of claim 6 wherein converting the plurality of visible light images to a plurality of corresponding binary images comprises processing the plurality of visible light images with respect to a threshold, such that pixel values that exceed the threshold are converted to a first color value and pixel values that are below the threshold are converted to a second color that is highly contrastive with respect to the first color.

9. The method of claim 5 wherein processing the plurality of visible light images comprises, at least in part:

filtering the corresponding reduced-dimensionality images to provide filtered images;

processing the filtered images using at least one of;

frequency domain processing techniques;

time domain processing techniques;

to identify heart beats.

10. The method of claim 9 wherein:

processing the filtered images using frequency domain processing techniques comprises, at least in part, using fast Fourier transforms processing techniques to identify the heart beats; and

processing the filtered images using time domain processing techniques comprises, at least in part, using at least one of;

peak detection processing techniques; and

zero crossing detection processing techniques;

to identify the heart beats.

11. The method of claim 1 wherein the apparatus is located remotely from the subject'"'"'s skin.

12. The method of claim 11 wherein processing the plurality of visible light images to thereby determine a heart rate for the subject comprises, at least in part:

monitoring time stamps as correspond to the plurality of images;

using the time stamps when processing the plurality of images to determine the heart rate for the subject.

13. The method of claim 11 further comprising:

transmitting determined heart rate information to the subject while continuing to received additional images and continuing to determine a subsequent heart rate for the subject.

14. The method of claim 1 wherein processing the plurality of visible light images to thereby determine a heart rate for the subject comprises, at least in part:

dynamically assessing image quality on a frame-by-frame basis to determine suitability of the images for use in determining the heart rate for the subject.

15. An apparatus comprising:

a visible light image capture component;

a processor operably coupled to the visible light image capture component and being configured and arranged to;

receive, from the visible light image capture component, a plurality of visible light images as correspond to a subject'"'"'s skin proximal to a blood-transporting capillary;

process the plurality of visible light images to thereby determine a heart rate for the subject.

16. The apparatus of claim 15 wherein the apparatus comprises a portable wireless two-way communications apparatus.

17. The apparatus of claim 15 wherein the visible light image capture component comprises a camera.

18. The apparatus of claim 17 wherein the apparatus further comprises a visible light source that is controlled to provide visible light to facilitate capturing visible light images via the visible light image capture component.

19. The apparatus of claim 18 wherein the visible light source comprises a display backlight.

20. The apparatus of claim 17 wherein the camera comprises a general purpose camera.