Device and process for regulating bit rate in system for the statistical multiplexing of image streams coded according to MPEG2 coding

摘要

A device for regulating bit rate in a system for statistically multiplexing several streams of MPEG 2 coded images is disclosed. The statistical multiplexing system includes a device (1) for allocating bit rate using the complexity calculated by a bit rate regulating device (10). Each coder E(i) of an image stream includes a first coding device (20) for performing spatial coding, a second coding device and a memory for storing the complexity X<1st>| of the last image coded spatially by the first coding device. The complexity (X<->GOP) of the last group of pictures is coded by the second coding device (30). Device (10) regulates the bit rate of coder E(i) for determining the complexity value for the next image coded by the second coding device (30), using stored complexity values. This complexity value is transmitted to the bit rate allocator (1) to determine the next bit rate sent to the coder E(i).