Transform Coding

The essence of transform coding is to transform signals from one domain (e.g., time domain) to another domain (e.g., frequency domain) with a set of orthogonal basis. The transform is beneficial to eliminate signal correlation and reduce data redundancy. In this chapter, we will introduce some important transforms, including the commonly used discrete cosine transform (DCT), the wavelet transform, and the graph Fourier transform (GFT). We also show several applications of transform-based methods in point cloud attribute compression.