摘要
为了避免图像去雾后细节模糊和噪声放大,将图像分解为结构层和纹理层,并只对其结构层进行去雾。基于频域滤波思想提出透射率融合方法,解决了现有透射率估计方法中普遍存在的块效应问题和复原图像中存在的晕轮伪影问题。针对透射率优化过程中存在的计算量大、透射率平滑与细节保持之间难以平衡等问题,提出了多重导向滤波透射率优化方法。同时,针对目前大气光估计易受图像中白色物体的影响,提出自适应大气光估计方法。实验结果表明,该算法得到的图像去雾彻底、细节清晰、颜色自然,不仅有效抑制噪声和晕轮伪影,而且显著提高场景对比度、饱和度。
In order to avoid the details blurring and noise amplification,the image is decomposed as structural layer and texture layer,and the dehazing operation is only performed on the structural layer.The transmission fusion method based on the idea of frequency domain filtering is proposed to remove the block effects in the transmission image and the halo artifacts in the restored image.To solve the problems existed in the transmission optimization process such as the complex computation,being incapable of keeping the balance between the transmission smoothing and details preservation,we propose the multi-guided filtering method.At the same time,an adaptive atmospheric light estimation method is proposed which can be applicable to the scenes with large white objects.Experimental results show that the proposed algorithm can remove the haze effectively and the restored image has clear details and natural color.The noise and halo artifacts are suppressed remarkably,and the contrast and saturation of the scene are improved significantly.
引文
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