VIDEO CODER AND VIDEO DECODER

摘要

PROBLEM TO BE SOLVED: To code a compression coding string without producing errors in an occupancy capacity of a video buffer in the case of decoding a video signal. SOLUTION: A video signal 128 is coded by a coder 103, which provides an output of a 1st compression coding stream 129, a generated code amount measurement device 104 measures it to deliver generated code amount 137, and a video buffer computer 111 calculates virtually a video buffer occupancy amount 140 based on the amount 137, a prescribed initial value 148 and a picture rate 147. When there is no overflow nor underflow in the video buffer occupancy amount 140, the 1st compression coding stream is outputted. When any overflow or underflow is detected, a playback coder 115 determines a playback point of time 146 and codes the video signal again. The re-coding is repeated till any overflow or underflow is not detected.