초록 ▼

The method and system for compressing color video data in a video communication system utilizes a three color digital signal, and involves the determination of a luminance function for each pixel in a series of video picture frames. One or more decision parameters based upon differences of the lumin

The method and system for compressing color video data in a video communication system utilizes a three color digital signal, and involves the determination of a luminance function for each pixel in a series of video picture frames. One or more decision parameters based upon differences of the luminance function between pixels are compared with corresponding adaptive thresholds to determine decision points in the scan lines, and the digital word size of the three digital color components is reduced before encoding of run lengths between decision points of the color values.

대표청구항 ▼

A method for compressing color video data in a video communication system having means for producing a color video signal for a plurality of video picture frames, with each picture frame comprising a plurality of scan lines composed of a plurality of pixels, each scan line having a starting pixel an

A method for compressing color video data in a video communication system having means for producing a color video signal for a plurality of video picture frames, with each picture frame comprising a plurality of scan lines composed of a plurality of pixels, each scan line having a starting pixel and an ending pixel, and each pixel in each said frame comprising three digital color component signals of first, second and third digital word sizes, respectively, said method comprising the steps of: (a) determining a luminance function for each pixel based upon at least one of said three digital color component signals; (b) determining at least one decision parameter for at least a substantial portion of the pixels in the scan lines of said picture frame based upon the difference of said luminance function between pixels at least one predetermined distance from at least one other pixel on each scan line; (c) determining the rate of change of said at least one decision parameter for each of said pixels for which said luminance function difference has been determined; (d) comparing said rate of change of said at least one decision parameter with a corresponding adaptive rate of change threshold to determine which of said pixels represent decision points; (e) reducing the word size of at least one of said three digital color components signals to provide one to three reduced digital color component signals of fourth, fifth, and sixth digital word sizes, respectively, for each said pixel; and (f) coding said plurality of pixels in each scan line as a plurality of combinations of pixel run lengths and said three reduced color component signals for each said run length, said run lengths being determined between said starting pixel for each scan line, intermediate points selected from the group of said decision points and points intermediate said decision points, and said ending pixel, and each run length being of a seventh digital word size.