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Image Compression Using
Vector Quantization
Vector quantization is an efcient technique used for compressing images. It
is based on the Shannon rate distortion theory, which says that better com-
pression is achieved if samples are coded using vectors instead of scalars.
The nite vectors of pixels are stored in a memory called codebook, which
is used for coding and decoding the images. The image to be compressed is
divided into blocks and called input vectors and are compared with vectors
in memory called codevectors for matches based on some distance criteria.
If the codevector matches the input vector, an index or address of memory
location ...