If error occurs when wavelet-coded images are transmitted over lossy packet networks

some part of the images will suffer from quality degradation. Traditional image reconstruction algorithms can be cataloged into space domain interpolation and wavelet domain estimation. In this paper

hybrid error concealment on both domains is presented

First

a simple reconstruction is carried out on wavelet domain by estimating the lost coefficients by its mean value of the surroundings in the low frequency subband. Second

we search for the match block of the kernel destroyed area according to the known correct wavelet coefficients. Finally

the image is re-transformed to wavelet domain after filtering

and the final reconstructed image is generated by combining both re-transformed coefficients and the original received coefficients. Experiments show that in most cases this method is better than the simple estimation by the mean value of low subband. PSNR is optimized by about 0.5 to 1 dB and the subjective image quality is also improved.