A new approach to bitstream extraction in H.264 SVC

Scalable Video Coding is a hot spot in video coding area. JVT is now working on SVC as an annex of the H.264/AVC. One important application of SVC is to deal with various networks conditions using its scalability. But due to the structure of the SVC bitstream and its extraction method, the resolution can only change from higher to lower resolutions, and not vice versa, unless each key frame of GOP was coded as I frame. It causes the dropping of coding efficiency. We present a new approach to bitstream extraction, which extracts all layers for each key frame, so the resolutions can change bidirectional while remains the coding efficiency.