摘要 |
A method and apparatus are provided for encoding of digital video signals in the form of video clips (A,B) to enable them to be seamlessly joined without requiring reset of a decoder to a starting state. The system uses an encoder having a coding stage and an encoder buffer, and comprises successively encoding the pictures of a clip according to a predetermined coding scheme (suitably according to MPEG standards), reading the encoded pictures into the buffer, and subsequently reading the encoded clip out of the buffer at a substantially constant bit rate. To enable simple joining of the clips, a predetermined encoder buffer occupancy (Bic) is specified with a controllably varied target number of bits being used to encode a picture. The targeting produces an encoder buffer occupancy substantially equal to the predetermined buffer occupancy (Bic) at the moment the last picture of the segment has been read into the buffer. Particular applications for the technique are in interactive video systems where the user can affect a narrative flow without having discontinuities in the presentation of that narrative. |