Tchebichef Moment Transform for colour image dithering
Hidayah Binti Rahmalan, Ferda Ernawan, Nur Azman Abu · 2012
Currently, small mobile devices may not have the capability to display high fidelity true colour images. It is expected to have limited capability in computational power and storage. However, a small mobile device is expected to perform efficiently in displaying images. A dithering technique is called for here in order to improve the perceptual visual quality of the limited bit depth images. Typically, a true colour image is reduced down to fewer bits per pixel. In order to efficiently dither a colour image on small mobile devices, this paper proposes 2×2 Tchebichef Moment Transform (TMT) approach. Earlier, a 2×2 Discrete Wavelet Transform (DWT) has been proposed for better image quality on dithering. The 2×2 TMT has been chosen since it performs better than the 2×2 DWT. TMT incorporates simplified mathematical framework technique using matrices. The result shows that 2×2 TMT gives perceptually better quality on colour image dithering in significantly efficient fashion.