McFIS: better I-frame for video coding

The conventional Intra (I-) frame is used for error propagation prevention, backward/forward play, random access, indexing, etc. This frame is also used as an anchor frame for referencing the subsequence frames. To get better rate-distortion performance a frame should have the following quality to be an ideal I-frame: the best similarity with the frames in a GOP, so that (i) when it is used as a reference frame for a frame in the GOP we need less bits to achieve the desired image quality; (ii) if any frame is missing at the decoding end we can retrieve the missing frame from it. In this paper we will generate a most common frame of a scene (McFIS) in a video sequence using dynamic background modelling and then encode it to replace the conventional I-frame. By using McFIS as an I-frame, we not only gain the above mentioned two benefits but also ensure adaptive GOP for better rate-distortion performance compared to the existing coding schemes. The experimental results confirm the superiority of our proposed scheme in comparison with the existing state-of-art methods by significant image quality and computation time. Index Terms—Video coding, uncovered background, light change, repetitive motion, H.264, motion estimation, multiple sprites, sprite, MRF, and multiple reference frames. 1