METHOD AND APPARATUS FOR VIDEO COMPRESSION USING EFFICIENT MULTIPLE TRANSFORMS

摘要

The present embodiments relate to a method and an apparatus for efficiently encoding and decoding video using multiple transforms. For example, a horizontal transform or a vertical transform may be selected from a set of transforms to transform prediction residuals of a current block of a video picture being encoded. In one example, the set of transforms includes: 1) only one transform with a constant lowest frequency basis function, 2) one or more transform with an increasing lowest frequency basis function, and 3) only one transform with a decreasing lowest frequency basis function. In one embodiment, the transform with a constant lowest frequency basis function is DCT-II, the transform with an increasing lowest frequency basis function is DST-VII (and DST-IV), and the transform with a decreasing lowest frequency basis function is DCT-VIII. At the decoder side, the corresponding inverse transforms are selected.