| 摘要 |
The invention relates to a coding method applied to digital video data available in the form of a video stream consisting of consecutive frames. These frames, divided into macroblocks, include at least I-frames, independently coded, or P-frames, temporally disposed between said I-frames and predicted from at least a previous I- or P-frame, or B-frames, temporally disposed between an I-frame and a P- frame, or between two P-frames, and bidirectionally predicted from at least these two frames between which they are disposed, said predictions of P- and B-frames being performed by means of a weighted prediction with unequal amount of prediction from the past and the future. According to the invention, this coding method comprises the following steps : a structuring step, provided for capturing coding parameters characterizing the said weighted prediction ; a computing step, for delivering statistics related to said parameters ; an analyzing step for determining a change of preference regarding the direction of prediction ; a step provided for detecting the occurrences of gradual scene changes ; a step provided for generating description data of said occurrences ; and a step for encoding the description data thus obtained and the original digital video data. |
