On the error concealment technique for DCT based image coding

This paper presents a new error concealment (EC) technique for DCT based image coding. In our approach, the damaged blocks are recovered utilizing the smoothness property of an image at the boundaries of the blocks. Based on the property, we first define an object function which represents the intersample variations between adjacent blocks. Then, the DCT coefficients which minimize the object function are estimated by finding a solution of a linear equation. And, we show that it can be decomposed and reduced into more simple sub-equations. Thus, the computational complexity of the proposed technique is very low, compared to the existing techniques. Computer simulation results show that the proposed algorithm recovers the damaged blocks even if the block loss rate (BLR) is as high as 10^-2