| 摘要 |
<p>A video signal recording device for recording a digital video signal coded by using motion compensation prediction and orthogonal tranformation (eg according to MPEG), includes means for judging the degree of deterioration of a picture when the video data is coded and decoded on the basis of said motion compensation prediction and orthogonal transformation, and means for adaptively changing the data rate of the coding in response to the output of said judging means. The coding data rate information is multiplexed with other additional information (eg audio data and error correction code data) which is added to the coded video data to be recorded, or is written in a predetermined region of the recording medium. The data coding may be effected in a first means which codes a video signal (including at least an intra-frame encoded frame) with quantisation at a rough quantisation level, or codes a thinned said video signal, or codes a low frequency region of said video signal subjected to orthogonal conversion, and in a second means which codes a residual difference component derived from the output of the first means, the data rate in the first or second means being adaptively changed.</p> |
