System and method for detecting start codes in MPEG video streams

There is disclosed systems for detecting start codes in MPEG video streams in a digital video recorder (DVR), and methods of operating the same. An exemplary MPEG decoder is capable of decoding received bitstreams and generating PES packets. The MPEG decoder includes a controller that detects start codes in the received bitstreams, each of such codes having a three-byte start code prefix and a one-byte start code value. The controller is operable to (i) fetch a thirty-two bit word of a received bitstream, (ii) determine whether a start code prefix and a start code value are properly aligned within the thirty-two bit word, and (iii) if not properly aligned within the thirty-two bit word, determine whether the least significant byte of the thirty-two bit word may be part of the start code prefix.