Abstract: A method and apparatus are provided for implementing B-picture scene changes. A prediction stage predicts a B-picture scene change based upon a sequence of statistical information in an encoder order and a reaction stage is responsive to the prediction stage for modifying a quantization scale of a rate control algorithm.

Abstract: A method and apparatus are provided for implementing B-picture scene changes. A prediction stage predicts a B-picture scene change based upon a sequence of statistical information in an encoder order and a reaction stage is responsive to the prediction stage for modifying a quantization scale of a rate control algorithm.

Abstract: An MPEG digital video decoder system, method and computer program product are presented for monitoring decoding of an encoded digital video signal for one or more predefined illegal conditions. Error detection logic is coupled to the variable length (VLC) decoder, inverse quantizer (IQ), inverse discrete cosine transformer (IDCT) and motion compensator (MC) of the decoder for detecting an illegal condition within at least one of the VLC decoder, IQ, IDCT and MC during decoding of the encoded digital video signal. The monitored illegal conditions can include a VLC/IQ control error, an IQ level overrun, and IQ/IDCT buffer error, an MC idle error and an MC macroblock start error. Error signals are reported to a central error register which is monitored periodically by the decoder's control processor. The control processor initiates recovery within the decoder system prior to stoppage of the system due to the illegal condition.

Abstract: A method of and apparatus for identifying a Dual Prime motion estimation best match and generating motion vectors pertaining thereto for inter-picture video compression in a motion picture having images of F.sub.1 and F.sub.2 parities. The Dual Prime method of motion estimation described herein includes a method of generating motion vectors. The motion vectors point from a macroblock in a current field to a macroblock in a past field for inter-picture video compression in a motion picture having images of F.sub.1 and F.sub.2 parities. The first step in the method is defining a macroblock in a parity field of the current picture. Next, the preceding field of the same or opposite parity is searched to find a first best match macroblock in the preceding field. Once a best match macroblock is found, a vector is formed from the current macroblock in the current parity field to the first best match macroblock in the preceding parity field.

Abstract: A digital video encoding method, apparatus and computer program product are described with enhanced encoding of a picture having a plurality of macroblocks. The approach is to partition the picture into at least two regions and then to set or adjust at least one encoding parameter for each macroblock of the picture based upon the region of the picture within which the macroblock is located. As one specific implementation, the picture is partitioned into a center region and at least one outer region and the at least one encoding parameter is set to enhance picture quality in the center region at the expense of picture quality in the at least one outer region. The encoding parameter can, for example, be a motion estimation parameter, a quantization value, or a target bits per macroblock.