Patent ID: 6574364
Filing Date: 2003-06-03
Classification: G09G,H04N

Abstract:
A method of encoding pixel color values for a digital video image frame, said method comprising the steps:assigning a color value to each different color within the image; identifying a predominant color for the image frame; and encoding runs of at least three successive pixels of the predominant color as a first code indicating a run and a second code indicating the run-length, characterized in that said method further comprises the step:encoding runs of successive pixels having a color other than the predominant color as successive iterations of a code containing only the respective color value when the run-length is less than or equal to a threshold value, and as a first code indicating a run, a second code indicating a run-length, and a third code identifying the color value when the threshold value is exceeded, wherein said method further comprises the steps:selecting one of the colors other than the predominant color; and specifying a range of run-lengths between minimum and maximum values for that color, wherein: runs of the selected color below the minimum value are coded as separate iterations of the color code; runs of the selected color between the minimum and maximum values are coded as a first code indicating a run of that color and a second code indicating the length; and runs of the selected color above the maximum value are coded as a first code indicating a run, a second code indicating a run-length, and a third code identifying the color value of the selected color.