Cabac macroblock rewind and end of slice creation to control slice size for video encoders

Abstract

This invention is computer implemented method of encoding video data into a compressed form. Encoding each macroblock in a frame of video data stores Context based Adaptive Binary Arithmetic Coding (CABAC) data in first and second CABAC engine registers. Each macroblock is classified into either a first type having recoverable CABAC engine registers or a second type having non-recoverable CABAC engine registers. The method closes a slice of data if the current macroblock exceeds a slice data size limit. The method restores or re-encodes previous macroblock CABAC engine registers dependent upon the states of the previous macroblock and the macroblock before that.