A Spatially Enhanced Error Concealment Technique and its Potential Alternative Application to Reduce H.264 Stream Sizes

With more and more video content being transmitted digitally and with user expectations continually rising, error concealment is becoming an increasingly important part of streaming media. Often overlooked in the past, even now manufacturers are often only doing the bare minimum necessary in order to avoid complexity. This paper first presents a combination of simple techniques that when combined produce an extremely effective concealment method that maintains spatially correlated edges throughout any lost data; this in turn gives an increase in both mathematical and visual performance when compared against the commonly used bilinear concealment technique. Secondly this paper looks at an alternative use of the bilinear passive error concealment algorithm that is often used by H.264 decoders. Occasionally a concealed macroblock is mathematically closer to the original than an encoded and decoded one, by removing these from the stream at the encoder and thus forcing the decoder to conceal the missing data, a significant reduction in the bit stream size (up to 5%) can be achieved with almost no loss in quality. Index terms Error Concealment, Spatial, Sobel, Rate Reduction, Edge Detection