An Improved Image Contrast Assessment Method
Abstract: Contrast is an
important factor affecting the image quality. In order to overcome the problems
of local band-limited contrast, a novel image contrast assessment method based
on the property of HVS is proposed. Firstly, the image by low-pass filter is
performed fast wavelet decomposition. Secondly, all levels of band-pass
filtered image and its corresponding low-pass filtered image are obtained by
processing wavelet coefficients. Thirdly, local band-limited contrast is
calculated, and the local band-limited contrast entropy is calculated according
to the definition of entropy. Finally, the contrast entropy of image is
obtained by averaging the local band-limited contrast entropy weighed using CSF
coefficient. The experiment results show that the best contrast image can be
accurately identified in the sequence images obtained by adjusting the exposure
time and stretching gray respectively, the assessment results accord with human
visual characteristics and make up the lack of local band-limited contrast.
Keywords: image quality
assessment, contrast, wavelet transform, contrast sensitivity, human visual system
Author: Yuanyuan Fan, Yingjun
Sang, Guang Hu, Zaijin Zhou, Yunrong Hao
Journal Code: jptkomputergg130052
