Title :
Block adaptive subband coding with optimized AMBTC
Author :
Chan, Ka Wing ; Chan, K.W.
Author_Institution :
Dept. of Electron. Eng., City Polytech. of Hong Kong, Kowloon, Hong Kong
Abstract :
A block adaptive SBC is combined with an adaptive AMBTC for near perfect reconstruction. The input images are decomposed into 4 subbands and are individually coded by AMBTC. The AMBTC will adapt to the signal variance and switch the output from 1 to 4 levels dynamically. Its performance is further optimized by Dynamic Range Tuning (DRT) and Central Aggregate Optimization (CAO). To avoid costly high precision coder, the lowest frequency band is further split into a coded subband and a residue one. All bands are coded by the same coder. Bit allocation is furnished by the dynamic adaptability of AMBTC, and a bit-reduction scheme derived from signal statistics of respective subbands. This 5-band coding system eliminates the blockiness and the jagged edge artifact completely. The simulation result also leads the closest one by a great margin
Keywords :
adaptive codes; data compression; image coding; image reconstruction; optimisation; 5-band coding system; Central Aggregate Optimization; Dynamic Range Tuning; adaptive AMBTC; bit allocation; bit-reduction scheme; block adaptive SBC; block adaptive subband coding; coded subband; image reconstruction; input images; jagged edge artifact; lowest frequency band; optimized AMBTC; signal statistics; signal variance; simulation result; Bit rate; Cities and towns; Decoding; Filters; Image coding; Image reconstruction; Quantization; Signal analysis; Signal synthesis; Switches;
Conference_Titel :
TENCON '94. IEEE Region 10's Ninth Annual International Conference. Theme: Frontiers of Computer Technology. Proceedings of 1994
Print_ISBN :
0-7803-1862-5
DOI :
10.1109/TENCON.1994.369266
