Locally Adaptive Passive Error Concealment for Wavelet Coded Images
This letter presents a novel locally adaptive error concealment method for subband coded images. For each lost low-frequency coefficient, we estimate the optimal interpolation weights from its neighborhood. The calculation of the interpolation weights is optimized in the mean squared error sense, and it takes into account the errors that would arise by horizontally and vertically interpolating the available neighbors of the lost coefficient. Compared to methods of similar complexity, the proposed scheme estimates the lost coefficients more accurately: on average, the PSNR is increased by up to 4.5 dB. The reconstructed images also look better, and our method is fast and of low complexity.