基于非均匀有序直方图和锐化的红外图像增强

Infrared Image Enhancement Based on Non-uniform Ordered Histogram and Sharpening

摘要:

由于受到光电测量设备硬件及环境的影响,采集到的红外图像普遍存在对比度低、噪声大等缺陷。为此,提出了一种基于非均匀有序直方图和锐化的红外图像增强算法。考虑到高动态范围红外图像的特性,该方法分为两部分:首先,通过引入在有序直方图域中以恒定斜率增加的非均匀分布来增强图像对比度,并将非均匀分布直方图与输入图像的排序直方图合并于有序直方图域的优化问题,以计算修正后的直方图。其次,为了更有效处理红外图像的模糊效应,提出一种用于高频补偿滤波的相对边缘强度指标,以有效地抑制相对均匀区域中的噪声。实验测试结果表明,与传统算法和其他类似算法相比,使用所提出的方法增强后的图像细节丰富,具有更好的视觉效果和更高的实际应用价值。

Abstract:

Due to the influence of the hardware and environment of optoelectronic measuring equipments, the collected infrared images generally have problems of low contrast and big noise. Thus, an infrared image enhancement method based on non-uniform ordered histogram and sharpening is proposed. Considering the characteristics of high dynamic range infrared images, the method is divided into two parts. Firstly, image contrast is enhanced by introducing a non-uniform distribution that increases at a constant slope in the ordered histogram domain. The non-uniform distribution histogram and the ordered histogram of the input image are merged into the optimization problem to calculate the corrected histogram. Secondly, in order to effectively deal with the blur effect of infrared image, a relative edge intensity index for high frequency compensation filtering is proposed to effectively suppress the noise in the relatively uniform region. The experimental results show that compared with various traditional algorithms and other similar algorithms, the enhanced image details of the proposed method are rich, with better visual effects and practical application value.