A Novel Video Coding Scheme with conditional interframe replenishment(CFR) algorithm based on DCT frequency domain is proposed in this paper. Utilizing the characteristics of DCT and visual perception of human

this DCT-based CFR algorithm can encode and decode motion pictures quickly and efficiently. Its compression ratio and reconstructed picture quality are similar with DCT/MC coding scheme such as H.261 and MPEG but with much lower complexity. Both simulation and practical video communication application have shown that this algorithm has high performance and ease of implementation. Because of its low computing complexity

it can be real-time realized by PC software. It can also work with H.261/MPEG by replacing ME/MC module(the motion vector is fixed as zero) after some little modifications on coding scheme. This DCT-based CFR algorithm and the video coding scheme are very suitable for low cost full PC software videophone

video conference and multimedia communication system.