Patent ID: 7010047
Filing Date: 2006-03-07
Classification: H04N

Abstract:
1. A pre-processing system for reducing identified brightness changes between a first video source frame and a subsequent second video source frame in a video frame sequence, the system comprising: a) an input for the video frame sequence, the sequence including the second source frame having an array of second source pixels; b) a frame memory for containing a first brightness compensated frame representing a brightness compensated version of the first source frame, the first compensated frame having an array of brightness compensated first pixels; c) a brightness pre-processor having a brightness model with at least two model parameters for identifying a brightness variation between a selected group of the second source pixels and a corresponding selected group of the compensated pixels; d) a brightness filter for selecting a suitable set of the model parameters for each group of the second source pixels and compensated pixels, the suitable parameter set used to calculate a brightness offset for reducing the identified brightness variation from the group of second source pixels to more closely correspond to the brightness level of the compensated pixels, thereby producing a second brightness compensated source frame; wherein the reduction of the brightness variation between the second source frame and the first compensated frame provides the second brightness compensated source frame for input to an encoder.