Application of resolution enhancement techniques on medical images

Ophthalmological imaging is widely used for the diagnosis of eye diseases. It is used to acquire high-quality images of either the cornea or the retina. Unfortunately, the acquired images have limited quality and resolution. The issue of visual quality and resolution enhancement of corneal images is the main concern in this paper. A framework is introduced for quality enhancement of corneal images with both histogram equalization and interpolation. Two models are presented in this framework. The first model comprises histogram equalization first and then interpolation, and the second one comprises interpolation first and then histogram equalization. Two types of image interpolation are considered: polynomial interpolation and inverse interpolation. These models are compared to achieve the best quality of corneal images. This best quality of corneal images is obtained with regularized interpolation first and then histogram equalization. The rationale behind this conclusion is that the utilization of regularization theory in interpolation presents smooth areas and reinforced edges.