This thesis describes an error concealment method for lost DCT coefficients in block-based still image coding. Lost DCT coefficients can be concealed such that the reconstructed block connects smoothly to adjacent blocks. If the smoothing method is applied to the concealment of high frequency coeffients, it may make a blurred image.
We propose a bidimensional linear interpolation method in the spatial domain which is adequate to conceal the high frequency coefficients. Proposed method interpolates the lost block by using boundary pels of adjacent blocks. This method can make the image with less blurred blocks. We also take into consideration the direction of object edge for the concealment of the lost blocks.
Simulation result show that the proposed method gives a good concealment performance for high frequency coefficients as well as low frequency coefficients in terms of PSNR and subjective quality.