Optimum quantization error feedback filter for wavelet image compression
In wavelet image compression, all information loss occurs during quantization. Based on the property of bi-orthogonal wavelets, optimal 2-D quantization error feedback filters are used to reduce the reconstruction error. With very low complexity with regard to computation and implementation, the error feedback system improves the PSNR of the reconstructed image by about 0.25 dB. In addition, due to its similar structure to the dithered quantizer, it also improves the subjective quality of the reconstructed image by reducing the contouring and ranging effects.