초록 ▼

The method and system of compressing and decompressing digital color video data in a video communication system utilizes a digital color video signal having three video color components, and involves the determination of a predetermined number of the most visually significant combinations of color c

The method and system of compressing and decompressing digital color video data in a video communication system utilizes a digital color video signal having three video color components, and involves the determination of a predetermined number of the most visually significant combinations of color components in a picture frame, and the encoding of the color components as compressed color codes in a series of run length and compressed color code combinations. Line-to-line differences and movement of edges and segments of the picture frames are determined, and frame-to-frame differences are also encoded to reduce the amount of information to a minimum. Further statistical encoding of at least a portion of the run length and color code combinations is also provided. The digitally compressed color component codes are decoded according to a look up table to form a table of the three digital color components for each run length, and the run lengths and corresponding color components are stored in an array in a buffer memory to represent the scan lines in a video picture frame.

대표청구항 ▼

A method for compressing digital color video data in a video telecommunication system having means for generating 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, and each pixel in said pictu

A method for compressing digital color video data in a video telecommunication system having means for generating 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, and each pixel in said picture frame comprising three digital color components, said method comprising the steps of: (a) determining a luminance function for each pixel based upon at least one of said three digital color components; (b) determining at least one decision parameter for at least a substantial portion of the pixels in the scan lines of a current picture frame based upon the difference of said luminance function between pixels a predetermined distance from at least one other pixel on each scan line; (c) comparing said at least one decision parameter with a corresponding threshold value to determine starting pixels and ending pixels for run lengths of sequentially related pixels in said scan lines, said run lengths being of a first digital word size, and said three color components being of second, third, and fourth digital word sizes, respectively; (d) encoding all of said digital color components in said picture frame according to a look up table of digitally compressed color codes of the most visually significant color combinations of a fifth digital word size smaller than the sum of said second, third and fourth digital word sizes; (e) encoding a plurality of combination of said run lengths and digitally compressed color codes representing at least a portion of said picture frame; (f) comparing said run lengths and digitally compressed color codes of said current picture frame with the run lengths and digitally compressed color codes of a previous picture frame to determine changes from said previous picture frame to said current frame; and (g) encoding said changes from said previous picture frame to said current picture frame for at least a portion of said picture frames, whereby once an initial picture frame is encoded, only those changes in subsequent picture frames are encoded.