Infrared image enhancement based on Riemann-Liouville fractional calculus and human visual properties

In order to improve the definition of the infrared image, and make it more accessible for human eyes, an infrared image enhancement algorithm based on Riemann-Liouville (R-L) fractional calculus and human visual properties is proposed in this paper. Combining the mathematical model of human retinal receptive field with R-L fractional calculus theory, an R-L fractional order Rodieck enhancement mask is designed. The mask is used to enhance the textures and edges of the image. Then, the grayscales of the enhancement result are adjusted according to the grayscale resolution capabilities of human eyes. It further improves the contrast of infrared images. Experimental results show that the proposed algorithm can effectively enhance the texture details and contrast of infrared images. Compared with histogram equalization method and multi-Retinex method, the enhancement result of the proposed algorithm has better visual effect, and it is more accessible for human eyes.