An error-based recursive filling ordering for image error concealment

Many image error concealment (EC) algorithms can be employed to reconstruct a lost region by dividing it into a set of (sub)blocks which are estimated from a set of known context pixels. In turn, these former pixels may have been previously obtained by estimation. In this situation, the order in which the lost region is recursively filled will clearly condition the resulting reconstruction. This paper proposes a novel filling order aimed to improve the performance of EC algorithms that are applied recursively over the lost area. It takes into account the reconstruction quality of the already concealed blocks in order to determine the filling order. Blocks surrounded by known pixels or by high quality reconstructions are prioritized. The proposed technique is applicable to a wide range of EC algorithms and achieves an improvement of up to 1dB (in PSNR) with negligible additional computational load.