基于透射率优化和颜色修正的水下图像增强方法

A method of underwater image enhancement based on transmittance optimization and color calibration

针对光在水中传输时受到水的吸收作用、悬浮颗粒散射作用而产生严重的衰减,导致水下光学图像对比度低、颜色失真的问题,提出一种基于透射率优化和颜色修正的水下图像增强方法。根据水下光学成像模型,采用最小信息量损失原理估计透射率,结合导向滤波提高透射率的估计精度,通过逆求解水下成像模型得到清晰化的水下图像。利用直方图均衡化进一步提高图像对比度,使用白平衡方法修正颜色。实验结果表明,该方法能够有效去除由后向散射引起的模糊,提高图像对比度和清晰度,同时修正色彩不平衡。

When light is transmitted in water, it is severely attenuated by water absorption and scattering of suspended particles, resulting in low contrast and color distortion of underwater optical image. In this paper, a method of underwater image enhancement based on transmittance optimization and color calibration was proposed. According to the underwater optical imaging model, the transmittance was estimated based on the principle of minimum information loss, and the estimated accuracy of transmittance was improved by combining with guidance filtering. The clear underwater image was obtained by inverse solution of the underwater imaging model. The histogram equalization was utilized to further improve image contrast, and white balance method was used to calibrate color. Experimental results show that this method can effectively remove the blur caused by backscattering, improve the contrast and clarity of the image, and correct the color imbalance.