Content-adaptive reference frame compression based on intra-frame prediction for multiview video coding

This paper presents a content-adaptive reference frame compression scheme to alleviate the large overhead of external memory communication during the Motion and Disparity Estimation process in Multiview Video Coding (MVC). Our scheme is based on a simplified intra-prediction process to reduce the spatial redundancy of the reference samples. The intra-prediction residue is compressed by a path composed of non-linear quantization and Huffman-based entropy encoder. Four different quantization strengths and Huffman tables were statistically defined. They are dynamically selected according to a content adaptation strategy, which classifies the original blocks based on their spatial homogeneity. Experimental results show that the proposed content-adaptive compression scheme is able to reduce the external memory accesses by up to 63% along with negligible losses in the MVC encoder rate-distortion performance. Compared to the best available related work [12] our content-adaptive reference frame compression achieves 39% reduced external memory accesses, while still providing a BD-PSNR increase of 0.03dB.