| 摘要 |
<p>The method of decomposition into subbands, of the type consisting in subjecting each sample E(n) to processing in parallel on a plurality of channels by prototype filtering modulated by a periodic function and sub-sampling by the number of subbands, consists in forming, in combination, a filtering (1), (2) of modified polyphase type and a processing by frequency transform (2), (1), which makes it possible to deliver a signal in subband Xk for each channel of corresponding rank. The reconstruction comprises, in combination, the dual (2), (1) frequency and modified polyphase filtering steps (1), (2) for delivering the reconstructed digital signal Rec(n). These corresponding modules for processing by frequency transform and by modified polyphase filtering are produced by means of MOT or PRMF filters. Application to all types of digital signals, especially television image signals. <IMAGE></p> |
