Patent ID: 7734088

Claim:
A method for improving bandwidth required to transmit at least a portion of a video stream comprising a plurality of image frames, each image frame comprising a set of pixels, the method comprising: using an update regions finder for: identifying a set of update pixels in a rendered image frame derived from an image frame of the video stream by comparing pixels in the rendered image frame with corresponding pixels in a stored image frame, the stored image frame representing a current state of an image frame at a receiver; using an edge position mask derived from edge pixels in the stored image frame to generate a reduced set of update pixels by removing from the set of update pixels any pixels that exist in the edge position mask; forming a plurality of update rectangles wherein each update rectangle comprises at least a portion of the reduced set of update pixels; and responsive to being able to improve the bandwidth required to transmit the plurality of update rectangles by merging at least two update rectangles.