HSI空间上高噪声彩色图像去噪方法研究

Research on High Noise Color Image Denoising Method in HSI Space

针对彩色图像中噪声难以去除的问题,根据HSI空间独特的色彩分离特点,对受高噪声污染的彩色图像的噪声去除进行了研究。首先将彩色图像投影到色彩特征空间HSI中,将色彩信息与亮度特征信息进行分离操作,然后对该空间中的色彩分量H和S提出极坐标下距离阈值去噪方法进行处理,在保持色彩不失真的情况下去除噪声。同时对亮度特征分量I进行多尺度变换得到高低频子图,根据高频子图中噪声突变频繁的特点提出自适应梯度阈值去噪方法去除高频中噪声以提高图像质量;采用稀疏去噪方法对低频子图中少量噪声进行处理;最后进行相应逆变换得到最终的彩色图像。实验结果表明,所提出的去噪方法在视觉上和PSNR、RMSE、SSIM、RE这些客观指标上均达到了良好的噪声去除效果。

In view of the difficulty of noise removal in color images,according to the unique color separation characteristics of HSI space,the noise removal of color image polluted by high noise is studied.Firstly,the color image is projected into the HSI of the color feature space,and the color information is separated from the intensity feature information.Then,the color components H and S in the space are processed with a method of distance threshold denoising in polar coordinates,so as to remove the noise without losing the true color.At the same time,multi-scale transformation is carried out on intensity feature component I to obtain the high and low frequency subgraph.According to the frequent noise mutation in the high frequency subgraph,an adaptive gradient threshold denoising method is proposed to remove the noise in the high frequency to improve the image quality.The sparse denoising method is adopted to deal with a small amount of noise in the low-frequency subgraph.Finally,the corresponding inverse transformation is carried out to obtain the final color image.The experimental results show that the method in this paper achieves good denoising effect in vision and objective indexes such as PSNR,RMSE,SSIM and RE.