IMPROVED ALGORITHMS FOR DETERMINING BITRATE FOR A STATISTICAL MULTIPLEXING SYSTEM TO ACCOUNT FOR SIGNAL COMPLEXITY INCLUDING FILM MODE AND GOP STRUCTURAL CHANGES

摘要

A statistical multiplexer (statmux) system for encoding multiple channels of digital television data is provided with improved algorithms for determining bitrate for encoding and decoding to account for signal complexity, including accounting for film mode and GOP structural changes. In film mode when the lower frame per second rate for film mode is identified, rather than faster rate SD or HD modes, instead of determining bit rate from viewing the next picture in the look ahead buffer (LAB), the system looks at a start time stamp for specific data in the LAB. Accounting for GOP structural changes includes identifying the number of pictures (N) between I type pictures in data provided to an encoder and the number of pictures (M) between P type pictures, rather than using a fixed number for N and M.