| 摘要 |
PURPOSE: To perform smooth reverse direction reproduction with relatively small memory capacity by preparing only a memory for storing I and P frames. CONSTITUTION: Encoding is performed in the order of frames 0(I), 3(P), 1(B), 2(B), 6(P), 4(B), 5(B)... and the sequence is rearranged to the order of the frames 27(I), 25(B), 9(I), 23(B), 22(B), 12(P)... in a buffer. Then, a memory group is constituted of reference frame memories (A-D) equivalent to four screens and an output memory equivalent to one screen, and at the time of using both front prediction and back prediction and reproducing movement compensation type compressed video signals in a reverse direction, the frames (I) and (P) to be referred to from the other frames are decoded in advance, restored pictures are tentatively stored and the frames (B) not to be referred to from the other frames are decoded in the order of reproduction. Thus, just by preparing the memory for storing the frames (I) and (P), the smooth reverse direction reproduction is realized. |
