Data hiding for error concealment of H.264/AVC video transmission over mobile networks

In this paper, a new data hiding-based error concealment algorithm is proposed. The method allows to increase the video quality in H.264/AVC wireless video transmission and Real-Time applications, where the retransmission is unacceptable. Data hiding is used for carrying to the decoder the values of 6 inner pixels of every macro-block (MB) to be used to reconstruct lost MBs into Intra frames through a bilinear interpolation process. The side information concerning a slice is hidden into another slice of the same frame, by properly modifying some quantized AC coefficients of the Integer Transform of the 16 blocks 4x4 composing the MBs of the host slice. At the decoder, the embedded information can be recovered from the bit-stream and used in the bilinear interpolation to reconstruct the damaged slice. This method, although allowing the system to remain fully compliant with the standard, improves the performance with respect to the conventional error concealment methods adopted by H.264/AVC, from the point of view of visual quality and Y-PSNR. In particular, it is possible to improve the result of the interpolation process adopted by H.264/AVC, reducing the distance between interpolating pixels from 16 to 5.