Adaptive Directional Lifting-Based Wavelet Transform for Image Coding

摘要: We present a novel 2-D wavelet transform scheme of adaptive directional lifting (ADL) in image coding. Instead alternately applying horizontal and vertical lifting, as practice, ADL performs lifting-based prediction local windows the direction high pixel correlation. Hence, it adapts far better to orientation features windows. The is achieved by existing 1-D wavelets seamlessly integrated into global transform. predicting updating signals can be derived even at fractional precision level achieve resolution, while still maintaining perfect reconstruction. To enhance performance, rate-distortion optimized segmentation also proposed form code hierarchical partition adapting features. Experimental results show that ADL-based coding technique outperforms JPEG 2000 both PSNR visual quality, with improvement up 2.0 dB on images rich