Method and system for compressing color video data

Claim 3

The method of claim 1, wherein the step of comparing said rates of change with an adaptive rate of change threshold to determine said decision points includes comparing at least one said decision parameters with an adaptive cumulative difference threshold.

Claim 4

The method of claim 1, wherein said first, second, and third digital word sizes are equal.

Claim 5

The method of claim 1, wherein at least two of said first, second, and third digital word sizes are equal.

Claim 6

The method of claim 1, wherein each of said first, second and third digital word sizes are different.

Claim 7

The method of claim 1, wherein said color video signal is RGB, and said three digital color component signals represent red, green, and blue color video components.

Claim 8

The method of claim 1, wherein said three digital color component signals represent cyan, magenta, and yellow color video components.

Claim 9

The method of claim 1, wherein said three digital color components are based upon hue, saturation, and intensity of said color video signal.

Claim 10

The method of claim 1, wherein the digital word size of each of said digital color components is six bits.

Claim 11

The method of claim 1, wherein each said combination of run length and reduced color components is coded as at least a 16 bit digital word.

Claim 12

The method of claim 1, further including the step of concatenating run lengths in said plurality of combinations of run lengths and reduced color components in a scan line which are associated with reduced color components whose differences are less than a predetermined color difference threshold.

Claim 13

The method of claim 1, wherein said three digital color component signals represent first and second colors and a parameter based upon luminance of the color video signal.

Claim 14

The method of claim 12, wherein the word size of each of said digital color components is reduced to 4 bits.

Claim 15

The method of claim 13, wherein each said combination of run length and reduced color components is coded as at least a 16 bit digital word.

Claim 16

The method of claim 1, wherein the step of determining said luminance function comprises summing each of said three digital color component signals.

Claim 17

The method of claim 15, wherein said luminance function has a digital word size of 8 bits.

Claim 18

The method of claim 15 wherein the step of determining said luminance function includes weighting of the sum of said three digital color component signals with respect to one or more of said three digital color component signals.

Claim 19

The method of claim 1, wherein a first decision parameter is determined from the difference in said luminance function between a first pixel and a second proximate pixel a distance of one pixel away from said first pixel on a scan line.

Claim 20

The method of claim 18, wherein a second decision parameter is determined from differences between said proximate pixel differences

Claim 21

The method of claim 18, wherein a cumulative decision parameter is determined from summing said proximate pixel differences.

Claim 22

The method of claim 1, wherein a first decision parameter is determined from the difference in said luminance function between a first pixel and a second proximate pixel a distance of two pixels away from said first pixel on a scan line.

Claim 23

The method of claim 21, wherein a second decision parameter is determined from differences between said proximate pixel differences.

Claim 24

The method of claim 21, wherein a cumulative decision parameter is determined from summing said proximate pixel differences.

Claim 27

The system of claim 24, wherein said means for comparing said rates of change includes means for comparing at least one said decision parameters with an adaptive cumulative threshold.

Claim 28

The system of claim 24, wherein said first, second, and third digital word sizes are equal.

Claim 29

The system of claim 24, wherein at least two of said first, second, and third digital word sizes are equal.

Claim 30

The system of claim 24, wherein each of said first, second and third digital word sizes are different.

Claim 31

The system of claim 24, wherein said color video signal is RGB, and said three digital color component signals represent red, green, and blue color video components.

Claim 32

The system of claim 24, wherein said three digital color component signals represent cyan, magenta, and yellow color video components.

Claim 33

The system of claim 24, wherein said three digital color component signals represent first and second colors and a parameter based upon luminance of the color video signal.

Claim 34

The system of claim 24, wherein said three digital color components are based upon hue, saturation, and intensity of said color video signal.

Claim 35

The system of claim 24, wherein said means for coding said plurality of pixels in each scan line is adapted to code each said combination of run length and reduced color components as at least a 16 bit digital word.

Claim 36

The system of claim 24, further including means for concatenating run lengths in said plurality of combinations of run lengths and reduced color components in a scan line which are associated with reduced color components whose differences are less than a predetermined color difference threshold.

Claim 37

The system of claim 24, wherein the digital word size of each of said digital color components is six bits.

Claim 38

The system of claim 35, wherein said means for reducing the word size of at least one of said three digital color component signals is adapted to reduce the word size of each of said digital color components to 4 bits.

Claim 39

The system of claim 36, wherein said means for coding said plurality of pixels in each scan line is adapted to code each said combination of run length and reduced color components as at least a 16 bit digital word.

Claim 40

The system of claim 24, wherein said means for determining said luminance function comprises means for summing each of said three digital color component signals

Claim 41

The system of claim 38, wherein said luminance function has a digital word size of 8 bits.

Claim 42

The system of claim 38, wherein said means for determining said luminance function includes means for weighting of the sum of said three digital color component signals with respect to one or more of said three digital color component signals.

Claim 43

In a camera for use in a video communication system, said camera being of the type 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 said frame comprising three digital color component signals of first, second and third digital word sizes, respectively, the improvement in said camera comprising: (a) means for determining a luminance function for each pixel based upon at least one of said three digital color component signals; (b) means for 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) means for 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) means for comparing said rate of change of said at least one decision parameters with a corresponding adaptive rate of change threshold to determine which of said pixels represent decision points; (e) means for reducing the word size of at least one of said three reduced 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; (f) means for 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.

Claim 44

In a camera for use in a video communication system, said camera being of the type 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 said frame comprising three digital color component signals of first, second and third digital word sizes, respectively, the improvement in said camera comprising: (a) means for determining a luminance function for each pixel based upon at least one of said three digital color component signals; (b) means for 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) means for 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) means for comparing said rate of change of said at least one decision parameters with a corresponding adaptive rate of change threshold to determine which of said pixels represent decision points; (e) means for reducing the word size of at least one of said three reduced 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; (f) means for 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.

Claim 45

The camera of claim 41, wherein said means for comparing said rates of change includes means for comparing at least one said decision parameter with an adaptive cumulative threshold.

Claim 46

The camera of claim 41, wherein said first, second, and third digital word sizes are equal.

Claim 47

The camera of claim 41, wherein at least two of said first, second, and third digital word sizes are equal.

Claim 48

The camera of claim 41, wherein each of said first, second, and third digital word sizes are different.

Claim 49

The camera of claim 41, wherein said color video signal is RGB, and said three digital color component signals represent red, green, and blue color video components.

Claim 50

The camera of claim 41, wherein said three digital color component signals represent cyan, magenta, and yellow color video components.

Claim 51

The camera of claim 41, wherein said three digital color component signals represent first and second colors and a parameter based upon luminance of the color video signal.

Claim 52

The camera of claim 41, wherein said three digital color component are based upon hue, saturation, and intensity of said color video signal.

Claim 53

The camera of claim 41, wherein said means for coding said plurality of pixels in each scan line is adapted to code each said combination of run length and reduced color components as at least a 16 bit digital word.

Claim 54

The camera of claim 41, further including means for concatenating run lengths in said plurality of combinations of run lengths and reduced color components in a scan line which are associated with reduced color components whose differences are less than a predetermined color difference threshold.

Claim 55

The camera of claim 41, wherein the digital word size of each of said digital color components is six bits.

Claim 56

The camera of claim 52, wherein said means for reducing the word size of at least one of said three digital color component signals is adapted to reduce the word size of each of said digital color components to 4 bits.

Claim 57

The camera of claim 53, wherein said means for coding said plurality of pixels in each scan line is adapted to code each said combination of run length and reduced color components as at least 16 bit digital word.

Claim 58

The camera of claim 41, wherein said means for determining said luminance function comprises means for summing each of said three digital color component signals.

Claim 59

The camera of claim 51, wherein said luminance function has a digital word size of 8 bits.

Claim 60

The camera of claim 55, wherein said means for determining said luminance function includes means for weighting of the sum of said three digital color component signals with respect to one of said three digital color component signals.