基于小波域反正切变换的红外图像增强算法

针对红外图像对比度低、噪声大的特点，利用由信息熵、信噪比和图像标准差构成的评价函数，提出一种平稳小波域的红外图像增强算法。以反正切变换为基础，设计在平稳小波域内增强红外图像对比度的非线性变换函数，并利用差分演化算法与评价函数，寻找最优的非线性变换参数。实验结果表明，与传统的小波域增强算法相比，该算法在有效增强红外图像对比度的同时，对噪声具有较强的鲁棒性。

Infrared Image Enhancement Algorithm Based on Arc-tangent Transform in Wavelet Domain

Because of noise and low contrast of the infrared image, an infrared image enhancement algorithm is proposed. Evaluating function is constructed by combing information entropy, signal-noise-ratio with standard variance in order to evaluate the enhanced image quality. Thus, an efficient nonlinear transform function is designed by arc-tangent transform in stationary wavelet domain so as to enhance the contrast of an infrared image. The optimal nonlinear transform parameter is obtained by combing differential evolution algorithm with the constructed evaluating function. Experimental results show that the proposed algorithm can efficiently enhance the contrast of the infrared image while getting a good robust to noise in the infrared image.