Efficient transform using canonical signed digit in reversible color transforms

bstract. Color transforms are important methods in the analysis nd processing of images. Image color transform and its inverse ransform should be reversible for lossless image processing appliations. However, color conversions are not reversible due to finite recision of the conversion coefficients. To overcome this limitation, eversible color transforms have been developed. Color integer ransform requires multiplications of coefficients, which are impleented with shift and add operations in most cases. We propose to se canonical signed digit (CSD) representation of reversible color ransform coefficients and exploitation of their common subexpresions to reduce the complexity of the hardware implementation sigificantly. We demonstrate roughly 50% reduction in computation ith the proposed method. © 2009 SPIE and IS&T. DOI: 10.1117/1.3206966