| 摘要 |
PCT No. PCT/GB92/00884 Sec. 371 Date Mar. 8, 1993 Sec. 102(e) Date Mar. 8, 1993 PCT Filed May 15, 1992 PCT Pub. No. WO92/21215 PCT Pub. Date Nov. 26, 1992.A temporally-subsampled video signal from a bandwidth reduction encoder is processed prior to transmission in order to reduce the judder effects that would otherwise be present when the encoded signal was viewed directly on a receiver not equipped with a bandwidth reduction decoder. A fraction 1/N of the samples are transmitted in the first field of each group of N fields, where N is the temporal subsampling ratio. Each of the other N-1 fields is formed by projecting the first field along the estimated motion trajectory to the appropriate time instant and adding to this projection the difference between another group of the N/1 samples and an estimate of these samples derived from those transmitted in the first field. At the decoder, the projected fields and the estimate of the samples can be derived from the samples in the first transmitted field of the group for each subsequent field. Using this information, the values of the other sets of samples can be derived from the subsequent transmitted fields, yielding the original temporally-subsampled signal. This signal is then decoded by the bandwidth reduction decoder. |
