In order to improve the bit allocation efficiency of Directionlet coding,a modified Breiman,Friedman,Olshen and Stone(BFOS) algorithm is suggested for rate consistent truncation.Two modifications are:(1) Dominant dire...In order to improve the bit allocation efficiency of Directionlet coding,a modified Breiman,Friedman,Olshen and Stone(BFOS) algorithm is suggested for rate consistent truncation.Two modifications are:(1) Dominant direction adjustment is proposed to balance the cost of sparse description and segment artifacts caused by discontinuous adjacent direction pairs.(2) Priority related merging is also proposed in the BFOS distortion list to find an optimal trimming element for unequal-importance bit allocation.Experimental results show that block effects could be removed without obvious bpp increment by selecting the dominant direction and its adjustment according to neighborhood homogeneity,and combined multi-PRIority(PRI) based merging of the M-ordered list offers unequal importance allocation and leads to a Peak Signal-to-Noise Ratio(PSNR) gain of 0.4 dB~1.3 dB.展开更多
基金Supported by The National Natural Science Foundation of China (No.60972133)Guangzhou Natural Science Foundation Team Project (No.9351064101000003 & 8451008901000615)
文摘In order to improve the bit allocation efficiency of Directionlet coding,a modified Breiman,Friedman,Olshen and Stone(BFOS) algorithm is suggested for rate consistent truncation.Two modifications are:(1) Dominant direction adjustment is proposed to balance the cost of sparse description and segment artifacts caused by discontinuous adjacent direction pairs.(2) Priority related merging is also proposed in the BFOS distortion list to find an optimal trimming element for unequal-importance bit allocation.Experimental results show that block effects could be removed without obvious bpp increment by selecting the dominant direction and its adjustment according to neighborhood homogeneity,and combined multi-PRIority(PRI) based merging of the M-ordered list offers unequal importance allocation and leads to a Peak Signal-to-Noise Ratio(PSNR) gain of 0.4 dB~1.3 dB.