Method for recognizing motion gesture commands
A computer capable of recognizing gesture commands is disclosed. Suppose that a user makes a gesture of swinging a hand from side to side in front of a camera associated with a computer. A camera module receives frames with shots of the gesture in order. The camera module calculates a gradation difference between corresponding pixels of each frame and a background image to generate a set of binarized differential images. The camera module then combines differential images to generate composite images. In response to a determination that any of the composite images matches a reference pattern, the camera module outputs a computer command. The computer command can be used to control the power state of the computer or start a specific application within the computer.
1. A method comprising:
receiving a plurality of consecutive frames of an object from an image sensor;
comparing a background image with a blur image included in each of said frames to determine a difference between gradation values of corresponding pixels;
generating a differential image and specifying a shape of a blur image corresponding to a reciprocating motion of said object from a synthesized image obtained by combining differential images;
comparing the shape of said reference pattern with the shape of said synthesized image;
and updating said background image when a portable computer detects an acceleration equal to or greater than a predetermined value.
2. The method of claim 1 , wherein identifying a shape of said blurred image includes determining a logical OR of said difference images.
3. A method comprising:
defining a reference pattern with which a command is associated:
setting an exposure time of an image sensor mounted on a computer to capture a blur image drawn by a gesture;
receiving a plurality of consecutive frames obtained by photographing said gesture with said image sensor;
comparing a background image to a blur image included in each frame;
determining a difference between gradation values of corresponding pixels and binarizing a difference;
generating a difference image and specifying the shape of said blurred image of said gesture from a synthesized image obtained by synthesizing difference images;
sending said command to a computer when it is determined that the shape of said blur image matches said reference pattern;
and updating said background image when said computer detects an acceleration equal to or greater than a predetermined value.
4. The method of claim 3 , comprising changing a power state of said computer in response to said command.
5. The method of claim 3 , comprising activating a predetermined application program by said computer in response to said command.
6. The method of claim 3 , wherein said shape of said reference pattern is a fan shape in which a blurred image is formed by a reciprocating motion of an arm around an elbow.