Digital Image Processing
Contrast enhancement using brightness preserving bi-histogram equalization
IEEE Transactions on Consumer Electronics
Contrast enhancement system using spatially adaptive histogram equalization with temporal filtering
IEEE Transactions on Consumer Electronics
IEEE Transactions on Consumer Electronics
Gray and color image contrast enhancement by the curvelet transform
IEEE Transactions on Image Processing
IEEE Transactions on Image Processing
An advanced contrast enhancement using partially overlapped sub-block histogram equalization
IEEE Transactions on Circuits and Systems for Video Technology
Hi-index | 0.00 |
In this paper, we present a block overlapped intensity-pair distribution based image enhancement algorithm. Instead of using the intensity-pair distribution of the whole image, this proposed algorithm takes the intensity-pair distribution block-wise and maps the intensity of the center pixel according to an expansion function. Analyzing the intensity difference of the intensity-pair, two different expansion force sets are generated for contrast stretch: one for soft edges, another for strong edges. In addition, a set of anti-expansion force is generated for smooth regions to avoid noticeable change. The contrast stretch and over-enhancement are controlled with a linear magnitude mapping function instead of a non-linear one. This linear mapping preserves the relative contrast enhancement ratio between the gray levels. The local information from blocks easily facilitates the contrast enhancement, brings out subtle edge information, and removes noises from the image.