Improvement of VQ Index Compression with Relative Index Tables

Index compression for vector quantisation using modified coding tree assignment scheme

“…Somasundaram and Domnic [26] extend the coding models used in [22, 25] and design a new hybrid coding model called adaptive index coding scheme (AICS) which gives better performance in bit rate than SOC, DTCS and ICS. In [27], Sun and Ku modify the LCIC [22] method to encode VQ indices by using relative index table called index searching algorithm with index associated list (ISAIAL) which obtains better performance. Moreover, they propose the modified ISAIAL [28] based on each row of the relative index table with different sizes.…”

“…In the paper, the modified coding tree assignment scheme (MCTAS) is presented to improve the coding efficiency of the image VQ scheme and reduce time complexity of the CTAS‐ISOC [29] technique by exploiting the correlations of the neighbouring blocks in the previously constructed index table. Experimental simulations show that the proposed scheme reaches better performance in bit rate than other popular existing lossless index compression methods, such as SOC [20], MSOC [21], LCIC [22], ICS [25], AICS [26], ISAIAL [27], modified ISAIAL [28] and CTAS‐ISOC [29].…”