Patent ID: 7499495

Claim:
A computer-implemented method of using a video decoder to transform video from a compressed form to a reconstructed form, the method comprising: receiving, at the video decoder, encoded data in a bit stream for a video sequence; and with the video decoder, decoding a picture in the video sequence using the encoded data, including: with the video decoder, decoding a variable length code indicating a motion vector range for a current frame, wherein the indicated motion vector range is selected from among plural extended ranges and a default range each represented with an associated variable length code in a variable length code table; and with the video decoder, reconstructing one or more motion vectors for blocks and/or macroblocks of the current frame based at least in part on the indicated motion vector range for the current frame, wherein the reconstructing comprises, for a motion vector component (mv), combining a motion vector differential component (dmv) with a motion vector predictor component (predictor) as follows: mv =( dmv+ predictor) s mod b; wherein the indicated motion vector range is from −b to b−1, and wherein smod is a signed modulus operation that assures mv is within the indicated motion vector range.