全局色调映射和局部对比度处理相结合的图像增强算法

Image Enhancement Algorithm Combining Global Tone Mapping and Local Contrast Processing

由于环境光照不足和亮度不均等客观因素的影响,低光照环境下采集的图像容易出现细节丢失和对比度降低等现象,现有的增强算法容易导致过曝光和细节处理不当等问题。针对上述问题,提出了一种全局色调映射和局部对比度处理相结合的图像增强算法。首先,将低照度图像从RGB颜色空间转换到HSI颜色空间;其次,采用自适应全局色调映射增强的方法对HSI空间图像的亮度分量I进行亮度增强;最后,通过局部对比度处理增强图像的细节,以期在对全局亮度进行增强的同时充分保留图像细节。实验结果表明,本文提出的算法能够有效提高低照度图像的整体亮度和对比度,增强图像细节,降低噪声,获得视觉效果良好的清晰图像。

Due to the influence of objective factors such as insufficient ambient light and uneven brightness,images collected in low-light environments are prone to loss of details and low contrast.Existing enhancement algorithms are likely to cause problems such as overexposure and inadequate detail processing and so on.In view of the above problems,an image enhancement algorithm combining global tone mapping and local contrast processing is proposed.First,the low-illuminance image is converted from the RGB color space to the HSI color space;second,the adaptive global tone mapping enhancement method is used to enhance the luminance component I of the HSI space image;finally,the details of the image are enhanced by local contrast processing,in order to enhance the global brightness while maintaining the image details.Experimental results show that the proposed algorithm can effectively improve the overall brightness and contrast of low-illuminance images,enhance image details,reduce noise,and obtain clear images with good visual effects.