Hyperspectral Data Processing: Algorithm Design and Analysis

19.5 3D Compression

Many 3D-cube image compression techniques are generally extended directly from their 2-D counterparts. Two 3D-cube compression techniques of particular interest that will be used in this chapter are JPEG2000 Multicomponent (ISO, 2000b) that is an extension of wavelet-based 2D-JPEG2000 (Taubman and Marcellin, 2000) and 3D-SPIHT, which is extended by 2D-SPIHT developed by Said and Pearlman (1996).

19.5.1 3D-Multicomponent JPEG

JPEG2000 (Taubman and Marcellin, 2000; Rucker et al., 2005) is a new still image compression standard that has replaced the commonly used DCT-based JPEG. It is a wavelet-based compression technique that adds/improves features such as coding of regions of interest, progressive coding, scalability, etc. The entire coding can be divided into four stages: tiling, discrete wavelets transform (DWT), scalar quantization, and block coding. The image is divided into rectangular regions called tiles; each tile gets encoded separately. The purpose of dividing images into tiles is that the decoder needs to decode only certain parts of the image on demand, instead of decoding the entire image and also less memory will be needed by the decoder to decode the image. After dividing the image into tiles, a wavelet transform is applied to each tile. The wavelet transform is followed by scalar quantization to quantize the sub-bands. The scalar quantized sub-bands representing different scales are coded using embedded block coding with block truncation (EBCOT) ...