For the compressed video, since an inter-frame depends on the previously encoded frame, the error in one inter-frame may propagate to the following inter-frames. In this paper, we present a new error-resilient coding scheme to alleviate the effect of error propagation for the new coding standard H.264. In this new coding standard, multiple reference frame is adopted to improve the coding efficiency. By making use of the reference frame buffer in the encoder, we can reference some macroblocks in every nth inter-frame to the frame that is n frames interval away, and these macroblocks are named as periodic macroblocks. The periodic macroblock can efficiently alleviate the error propagation between two frames that contain periodic macroblocks. We prove it in theory that encoding selected periodic macroblocks will reduce the loss probability of pixel. The selection of periodic macroblock is based on the distortion expectation of each macroblock in every nth frame. The number of periodic macroblocks in every nth frame can be adjusted according to the available transmission bandwidth, as the periodic macroblock will consume little more bits. The simulation results prove that the periodic macroblocks can obviously improve the quality of video at different macroblock loss rates. When the macroblock lost rate is 15% in every frame, the PSNR of video sequence can be improved about 3dB with 5% bitrate increase.
ASJC Scopus subject areas
- Media Technology
- Electrical and Electronic Engineering