Statistical multiplexing system and statistical multiplexing method for video coding code streams

The invention discloses a statistical multiplexing system and a statistical multiplexing method for video coding code streams. The system comprises a preprocessing module group, a statistical strategy control module, a coding module group and a multiplexing module, wherein the preprocessing module group comprises N preprocessing modules, each program corresponds to one preprocessing module, each preprocessing module calculates SAD of video images of each program, and original data of each program is transmitted to the coding module group; the statistical strategy control module distributes a target bitrate to each program according to the SAD of all of the programs and the latest actual bitrate of each program; the coding module group comprises N coding modules, each program corresponds to one coding module, and each coding module carries out coding on each program according to the target bitrates distributed by the statistical strategy control module; and the multiplexing module multiplexes the data streams, which are generated by the coding modules, of all of the programs into a TS (transport stream), monitors the actual bitrate of each program, and transmits the actual bitrate of each program to the statistical strategy control module. According to the system and the method disclosed by the invention, the bitrate required by programs in the future can be estimated more accurately, thereby improving the efficiency of statistical multiplexing.