Abstract
Two-point lossless rotation transforms are used on realizing lossless DCTs or lossless orthogonal wavelet transforms. However, two-point lossless rotation transforms based on the ladder network do not have high compatibility with their non-lossless versions. Therefore, in this paper, we propose two-point lossless rotation transforms with periodic structure and compare them with those based on the ladder network. We design the corresponding tables by making use of periodic structure after supplementary rotation transforms or supplementary widening conversions without replacing the transform matrix with the integer transform matrix. Accordingly, the proposed method is simple and the size of corresponding table is smaller than that of the conventional method. Since we can design the corresponding tables in consideration of compatibility with the non-lossless transforms, we can design the lossless rotation transforms that have high compatibility with them. Computer simulations show that the proposed methods have higher compatibility with non-lossless rotation transforms than the methods based on the ladder network.
