Gesture detecting method, gesture detecting apparatus, and recording medium

• US 20050271252A1
• Filed: 06/03/2005
• Published: 12/08/2005
• Est. Priority Date: 06/08/2004
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Yamada, Miki
• Granted Patent: US 7,650,017 B2
• Time in Patent Office: Days
• US Class Current: 382/103
• CPC Class Codes: G06V 40/165 using facial parts and geometric relationships
• CPC Class Codes: G06V 40/20 Movements or behaviour, e.g. gesture recognition recognition of facial expressions G06V40/16

Abstract

A gesture detecting apparatus prepares time series data of coordinates of specific part of object gesturing, calculates velocity vector of the specific part from the time series data of coordinates, to obtain time-series velocity vectors, detects dynamic periods when displacement per unit time of the specific part is larger than predetermined value, based on the time-series velocity vectors, acquires each representative velocity vector from velocity vectors in each dynamic period, stores the each representative velocity vector corresponding to the each dynamic period in memory, calculates first intersection angle of two representative velocity vectors stored in the memory, the two representative velocity vectors corresponding to two successive dynamic periods, and detects that the motion of the specific part is reciprocating motion when the first intersection angle is larger than first threshold value.

Claims

1. A gesture detecting method comprising:

preparing a time series data of coordinates of a specific part of an object gesturing;

calculating a velocity vector of the specific part from the time series data of coordinates, to obtain a time-series velocity vectors;

detecting dynamic periods when displacement per unit time of the specific part is larger than a displacement threshold value, based on the time-series velocity vectors;

acquiring each representative velocity vector from velocity vectors in each dynamic period;

storing the each representative velocity vector corresponding to the each dynamic period in a memory;

calculating a first intersection angle of two representative velocity vectors stored in the memory, the two representative velocity vectors corresponding to two successive dynamic periods; and

detecting that the motion of the specific part is a reciprocating motion when the first intersection angle is larger than a first threshold value.

2. The gesture detecting method according to claim 1, wherein the detecting the dynamic periods detects the dynamic periods when magnitudes of velocity vectors are larger than a velocity threshold value.

3. The gesture detecting method according to claim 1, which includes:

calculating a second intersection angle of two representative velocity vectors stored in the memory, the two representative velocity vectors corresponding to two dynamic periods every two dynamic periods;

detecting that the motion of the specific part is a repetitive motion which is a motion repeating the reciprocating motion, when the first intersection angle is larger than the first threshold value and the second intersection angle is smaller than a second threshold value.

4. The gesture detecting method according to claim 1, wherein the representative velocity vector is one of the velocity vectors in the each dynamic period, the representative velocity vector whose magnitude being the largest one of the velocity vectors in the each dynamic period.

5. The gesture detecting method according to claim 1, wherein the representative velocity vector is an average velocity vector of the velocity vectors in the each dynamic period.

6. The gesture detecting method according to claim 1, wherein the representative velocity vector is a velocity vector at a central time of the each dynamic period.

7. The gesture detecting method according to claim 1, wherein the time series data of coordinates is time series data of coordinates of specific part of a head of the object gesturing.

8. The gesture detecting method according to claim 1, wherein the preparing includes preparing the time series data of coordinates by calculating a coordinate of the specific part of the object from each of frames of moving picture of the object gesturing.

9. The gesture detecting method according to claim 1, wherein the velocity vector is an angular velocity vector.

10. The gesture detecting method according to claim 1, wherein the detecting the each dynamic period includes:

detecting a time point when magnitude of one of the time-series velocity vectors are larger than a velocity threshold value and magnitude of another of the time-series velocity vectors immediately prior to the one of the time-series velocity vectors is smaller than the velocity threshold value; and

acquiring the dynamic period which starts at the time point and is a predetermined amount of time.

11. The gesture detecting method according to claim 1, wherein the detecting the each dynamic period includes detecting each static period when magnitudes of the velocity vectors are smaller than or equal to a velocity threshold value;

and

detecting the dynamic period which is between two successive static periods.

12. A gesture detecting method comprising:

preparing a time series data of coordinates of a specific part of an object gesturing;

calculating a velocity vector of the specific part from the time series data of coordinates, to obtain a time-series velocity vectors;

detecting a representative velocity vector whose magnitude is larger than a velocity threshold value and maximum, from the time-series velocity vectors, to obtain time-series representative velocity vectors;

storing the time-series representative velocity vectors in a memory;

calculating a first intersection angle of two successive representative velocity vectors stored in the memory; and

detecting that the motion of the specific part is a reciprocating motion when the first intersection angle is larger than a first threshold value.

13. The gesture detecting method according to claim 12, which includes:

calculating a second intersection angle of two representative velocity vectors every two representative velocity vectors stored in the memory; and

detecting that the motion of the specific part is a repetitive motion which is a motion repeating the reciprocating motion, when the first intersection angle is larger than the first threshold value and the second intersection angle is smaller than a second threshold value.

14. A computer program stored on a computer readable medium, the computer program comprising:

first program instruction means for instructing a computer processor to prepare a time series data of coordinates of a specific part of an object gesturing;

second program instruction means for instructing a computer processor to calculate a velocity vector of the specific part from the time series data of coordinates, to obtain a time-series velocity vectors;

third program instruction means for instructing a computer processor to detect dynamic periods when displacement per unit time of the specific part is larger than a displacement threshold value, based on the time-series velocity vectors;

fourth program instruction means for instructing a computer processor to acquire a representative velocity vector from velocity vectors in each dynamic period;

fifth program instruction means for instructing a computer processor to store each representative velocity vector corresponding to the each dynamic period in a memory;

sixth program instruction means for instructing a computer processor to calculate a first intersection angle of two representative velocity vectors corresponding to two successive dynamic periods stored in the memory; and

seventh program instruction means for instructing a computer processor to detect that the motion of the specific part is a reciprocating motion when the first intersection angle is larger than a first threshold value.

15. The computer program of claim 14, further comprising:

eighth program instruction means for instructing a computer processor to calculate a second intersection angle of two representative velocity vectors stored in the memory, the two representative velocity vectors corresponding to two dynamic periods every two dynamic periods;

ninth program instruction means for instructing a computer processor to detect that the motion of the specific part is a repetitive motion which is a motion repeating the reciprocating motion, when the first intersection angle is larger than the first threshold value and the second intersection angle is smaller than a second threshold value.

16. A gesture detecting apparatus comprising:

a preparing unit configured to prepare a time series data of coordinates of a specific part of an object gesturing;

a first calculating unit configured to calculating a velocity vector of the specific part from the time series data of coordinates, to obtain a time-series velocity vectors;

a first detecting unit configured to detect dynamic periods when displacement per unit time of the specific part is larger than a displacement threshold value, based on the time-series velocity vectors;

an acquiring unit configured to acquire a representative velocity vector from velocity vectors in each dynamic period;

a memory to store each representative velocity vector corresponding to the each dynamic period;

a second calculating unit configured to calculate a first intersection angle of two representative velocity vectors corresponding to two successive dynamic periods; and

a second detecting unit configured to detect that the motion of the specific part is a reciprocating motion when the first intersection angle is larger than a first threshold value.

17. The gesture detecting apparatus according to claim 16, further comprising:

a third calculating unit configured to calculate a second intersection angle of two representative velocity vectors corresponding to two dynamic periods every two dynamic periods;

a third detecting unit configured to detect that the motion of the specific part is a repetitive motion which is a motion repeating the reciprocating motion, when the first intersection angle is larger than the first threshold value and the second intersection angle is smaller than a second threshold value.