BUFFERING FOR DIGITAL VIDEO SIGNAL ENCODERS USING JOINT BIT-RATE CONTROL

摘要

Video signal encoding apparatus, suitable for multiple video channels (A, B) has respective encoder stages (10, 12) which encode a received video signal according to a predetermined coding scheme, such as MPEG standard, and output a variable bit-rate data stream to encoder channel buffering (16) which is combined in a single buffer (16) having a fixed physical size with separate portions assigned to each channel. Buffer management (18) varies the size of the effective buffer areas assigned to the respective channels to maintain the total effective buffer area close to but within the physical limits of the buffer, as defined by the overall sum of encoder output bit rates. The outputs of the encoder buffer are combined into a single data stream, suitably by multiplexing (28), for subsequent separation and decoding by a receiver (30 to 36).