Video Error Concealment Techniques for Multi-Broadcast Reception of Digital TV

The transmission of digital TV signals to mobile receivers is often error-prone. As most TV broadcasting techniques provide only moderate error robustness, horizontal lines of consecutive image blocks are lost during decoding of the received video signals. In order to ensure high viewing experiences, these lost slices have to be filled by error concealment techniques. However, the reconstruction qualities of classical approaches which exploit spatial, temporal, or spatio-temporal signal correlations are not convincing yet.

In the future, mobile TV receivers will support different broadcasting techniques in parallel. As a result, an erroneous high-resolution video signal and a correctly received low-resolution video signal, both representing the same TV service, will often be available. Focusing on the outlined scenario for multi-broadcast reception of digital TV signals, this thesis introduces the novel category of inter-sequence error concealment algorithms. The basic idea is to fill lost slices of the high-resolution video signal by the interpolated low-resolution video signal. Since the images of this reference signal are often cropped and delayed, robust spatio-temporal image alignment is crucial. By including a pixel-based or a feature-based alignment scheme, the proposed concealment algorithms provide excellent visual qualities and outstanding reconstruction qualities of up to 41 dB PSNR. Classical concealment techniques are outperformed by up to 15 dB PSNR.