A Comparative Study of Effects of CSC on Image Compression Ratios While Using JPEG-XR

Image compression algorithms involves three basic processes i.e. Color Space Conversion, Frequency transformation and Entropy encoding. The Color Space Conversion (CSC) is one of the most important process and can influence the compression and quality of the image. JPEG XR uses a CSC which is different from the traditional image compression algorithms. JPEG XR also supports many image input formats like RGB, YUV, CMYK, Monochrome and arbitrary N-channel color formats. JPEG XR uses the same Frequency Transformation and entropy encoding for all the input image formats. In case of JPEG XR, there is a flexibility of using different CSC for different input image formats like RGB and CMYK. The JPEG XR bypasses the CSC for images having uncorrelated data like YUV. There is lot of literature available on comparison of JPEG XR with other image compression algorithms like JPEG, but there is very little research or literature on comparing the image compression ratios and quality of images in different formats using JPEG XR compression algorithm. In this study, An analysis and comparison of the compression ratios of the images of different input formats in particular to RGB input format and YUV 444 format has been carried out to explore the effects of CSC on the image compression while using the JPEG XR. An analysis of effective compression (better compression ratio) has been carried out on various images of unique visual characteristics in different input formats when processed using JPEG XR.