Wyner-Ziv coding of motion video

In current interframe video compression systems, the encoder performs predictive coding to exploit the similarities of successive frames. The Wyner-Ziv theorem on source coding with side information available only at the decoder suggests that an asymmetric video codec, where individual frames are encoded separately, but decoded conditionally (given temporally adjacent frames) could achieve similar efficiency. We report the first results on a Wyner-Ziv coding scheme for motion video that uses intraframe encoding, but interframe decoding.

1: Introduction

Current video compression standards perform interframe predictive coding to exploit the similarities among successive frames. Since predictive coding makes use of motion estimation, the video encoder is typically 5 to 10 times more complex than the decoder. This asymmetry in complexity is desirable for broadcasting or for streaming video-on-demand systems where video is compressed once and decoded many times. However, some future systems may require the dual scenario. For example, we may be interested in compression for mobile wireless cameras uploading video to a fixed base station. Compression must be implemented at the camera where memory and computation are scarce. For this type of system what we desire is a low-complexity encoder, possibly at the expense of a high-complexity decoder, that nevertheless compresses efficiently.