Robust Streaming of Offline Coded H.264/AVC Video Via Alternative Macroblock Coding
An error resilient video streaming scheme that transmits offline coded H.264/AVC video through erroneous channels, called the alternative macroblock coding (AMC) scheme, is proposed in this work. In the AMC scheme, each macroblock can be reconstructed from one default and several alternative versions coded using different predictions. During the transmission, the sender tracks ACK or NACK messages from the receiver to detect transmission errors. When the reference used in the default version of a macroblock that has not been transmitted is corrupted by errors, one of its alternative versions that has the correctly received reference is selected to replace the default version in the output bit stream to stop error propagation. The AMC scheme is designed to ensure that the bit stream replacement during streaming will not cause significant mismatch at the decoder end and neither introduce large bit rate overhead to the transmitted bit stream. Furthermore, adaptive quantization selection and bit stream replacement methods are developed to improve the rate-distortion performance of received video. It is demonstrated by experimental results that the AMC scheme is effective in reducing error propagation in offline coded H.264/AVC video.