A Class of Low-Complexity DCT-Like Transforms for Image and Video Coding

The discrete cosine transform (DCT) is a relevant tool in signal processing applications, mainly known for its good decorrelation properties. Current image and video coding standards—such as JPEG HEVC—adopt the DCT fundamental building block compression. Recent works have introduced low-complexity approximations DCT, which become paramount applications demanding real-time computation low-power consumption. design of involves trade-off between computational complexity performance. This paper introduces new multiparametric class encompassing round-off (RDCT) modified RDCT (MRDCT), two multiplierless 8-point approximate DCTs. associated fast algorithm provided. Four novel orthogonal are obtained by solving multicriteria optimization problem. optimal transforms scaled to lengths 16 32 while keeping arithmetic low. proposed methods assessed proximity measures with respect exact DCT. Image experiments hardware realization performed. perform close or outperform current state-of-the-art approximations.