摘要 |
PCT No. PCT/NO92/00144 Sec. 371 Date Apr. 20, 1994 Sec. 102(e) Date Apr. 20, 1994 PCT Filed Sep. 8, 1992 PCT Pub. No. WO93/05612 PCT Pub. Date Mar. 18, 1993.Smoothing of regenerated digital pictures (e.g. after a heavy signal compression and coding for transmission on a narrowband medium) can be effected by means of a so-called "cosmetics filter" which filter comprises a digital lowpass filter, a delay, a subtraction unit, a table and an adder. An input signal enters the lowpass filter and the delay which is arranged in parallel with the lowpass filter. The difference between the delayed signal and the lowpass-filtered signal is used to address the table. An address content from the table is passed to the adder to be added to the lowpass-filtered signal from the lowpass filter, and the sum signal from the adder is the final filtered signal to the output from the cosmetics filter. |