Interpreting sign language gestures

• US 7,949,157 B2
• Filed: 08/10/2007
• Issued: 05/24/2011
• Est. Priority Date: 08/10/2007
• Status: Expired due to Fees

• Current Assignee: Asian Institute of Technology
• Original Assignee: Asian Institute of Technology
• Inventors: Phuc, Trinh Huu, Afzulpurkar, Nitin
• Primary Examiner(s): Werner; Brian P
• Application Number:
  US11/837,283
• Publication Number:
  US 20090040215A1
• Time in Patent Office: 1,383 Days
• Field of Search: None
• US Class Current: 382/115
• CPC Class Codes: G06V 40/28 Recognition of hand or arm movements, e.g. recognition of deaf sign language static hand signs G06V40/113

Abstract

Embodiments of the invention include methods and apparatuses relating to identifying hand gestures. In one embodiment, a hand gesture is identified by capturing an image including an image object of the hand gesture, generating a numerical signature based on the image object, and identifying the hand gesture from reference numerical signatures associated with reference hand gestures.

Claims

1. A method for a computer system to recognize a hand gesture comprising:

obtaining a captured image at an image capture device, wherein the captured image includes an image object, the image object being an image of a hand, and saving the captured image as a file on the computer system;

generating a numerical signature at the computer system based on the image object, wherein the numerical signature includes a dimensional ratio of a length of a segment, the length of the segment created by an intersection between a boundary of the image object and a vertical scanning line, and a height of the image object;

providing a plurality of reference numerical signatures at the computer system, the plurality of reference numerical signatures having a plurality of reference hand gestures associated therewith; and

identifying one of the plurality of reference numerical signatures as being descriptive of the numerical signature, wherein a hand gesture corresponding to the one of the plurality of reference numerical signatures is attributable to the image of the hand; and

producing a visual or audio output based on the hand gesture attributed to the image of the hand.

2. The method of claim 1, wherein the numerical signature comprises a second dimensional ratio of the image object, the second dimensional ratio being calculated as:

3. The method of claim 1, wherein the vertical scanning line is scanned at 34% of the width of the image object.

4. The method of claim 1, wherein the numerical signature comprises a number of intersections between a boundary of the image object and a horizontal scanning line.

5. The method of claim 1, wherein the hand gesture comprises one of the American Sign Language (ASL) gestures.

6. The method of claim 1, further comprising:

arranging the plurality of reference hand gestures in a hierarchical structure at the computer system, wherein the hierarchical structure is arranged according to the plurality of reference numerical signatures corresponding thereto, and wherein the hierarchical structure enables searching of the plurality of reference hand gestures.

7. The method of claim 1, further comprising:

obtaining a second captured image at the image capture device, wherein the second captured image includes a second image object, the second image object being a second image of the hand, and saving the second captured image as a second file on the computer system;

determining whether the second captured image is substantially similar to the captured image at the computer system; and

if the second captured image and the captured image are not substantially similar, attributing a second hand gesture to the captured image and the second captured image at the computer system.

8. A machine readable non-transitory medium having stored therein a plurality of instructions that, when executed, cause the machine to identify a hand gesture by:

receiving a captured image including an image object, the image object being an image of a hand;

generating a numerical signature based on the image object, wherein the numerical signature includes a dimensional ratio of a length of a segment, the length of the segment created by an intersection between a boundary of the image object and a vertical scanning line, and a height of the image object;

receiving a plurality of reference numerical signatures, the plurality of reference numerical signatures having a plurality of reference hand gestures associated therewith; and

identifying one of the plurality of reference numerical signatures being descriptive of the numerical signature, wherein a hand gesture corresponding to the one of the plurality of reference numerical signatures is attributable to the image of the hand.

9. The machine readable non-transitory medium of claim 8, wherein the numerical signature comprises a second dimensional ratio of the image object, the second dimensional ratio being calculated as:

10. The machine readable non-transitory medium of claim 8, wherein the vertical scanning line is scanned at 34% of the width of the image object.

11. The machine readable non-transitory medium of claim 8, wherein the numerical signature comprises a number of intersections between a boundary of the image object and a horizontal scanning line.

12. The machine readable non-transitory medium of claim 8, wherein the hand gesture comprises one of the American Sign Language (ASL) gestures.

13. The machine readable non-transitory medium of claim 8, further comprising instructions that, when executed, cause the machine to identify a hand gesture by:

arranging the plurality of reference hand gestures in a hierarchical structure according to the plurality of reference numerical signatures corresponding thereto, wherein the hierarchical structure enables searching of the plurality of reference hand gestures.

14. The machine readable non-transitory medium of claim 8, further comprising instructions that, when executed, cause the machine to identify a hand gesture by:

obtaining a second captured image including a second image object, the second image object being a second image of the hand;

determining whether the second captured image is substantially similar to the captured image; and

if the second captured image and the captured image are not substantially similar, attributing a second hand gesture to the captured image and the second captured image.

15. An apparatus comprising:

a machine readable medium having stored therein a plurality of instructions that, when executed, cause the apparatus to identify a hand gesture by;

receiving a captured image including an image object, the image object being an image of a hand;

generating a numerical signature based on the image object, wherein the numerical signature includes a dimensional ratio of a length of a segment, the length of the segment created by an intersection between a boundary of the image object and a vertical scanning line, and a height of the image object;

receiving a plurality of reference numerical signatures, the plurality of reference numerical signatures having a plurality of reference hand gestures associated therewith; and

identifying one of the plurality of reference numerical signatures being descriptive of the numerical signature, wherein a hand gesture corresponding to the one of the plurality of reference numerical signatures is attributable to the image of the hand; and

a processor coupled to the machine readable medium to execute the programming instructions.

16. The apparatus of claim 15, wherein the numerical signature comprises a second dimensional ratio of the image object, the second dimensional ratio being calculated as:

17. The apparatus of claim 15, wherein the vertical scanning line is scanned at 34% of the width of the image object.

18. The apparatus of claim 15, wherein the numerical signature comprises a number of intersections between a boundary of the image object and a horizontal scanning line.

19. The apparatus of claim 15, wherein the hand gesture comprises one of American Sign Language (ASL) gestures.

20. The apparatus of claim 15, wherein the machine readable medium further comprises instructions that, when executed, cause the apparatus to identify a hand gesture by:

arranging the plurality of reference hand gestures in a hierarchical structure according to the plurality of reference numerical signatures corresponding thereto, wherein the hierarchical structure enables searching of the plurality of reference hand gestures.

21. The apparatus of claim 15, wherein the machine readable medium further comprises instructions that, when executed, cause the apparatus to identify a hand gesture by:

obtaining a second captured image including a second image object, the second image object being a second image of the hand;

determining whether the second captured image is substantially similar to the captured image; and

if the second captured image and the captured image are not substantially similar, attributing a second hand gesture to the captured image and the second captured image.