利用大气非均匀路径中的图像退化光学模型建立了一种非均匀大气中退化图像复原的新方法.首先估计得到图像中各目标倾斜方向对应的观测处天空背景亮度,然后根据暗原色先验知识估计出图像中场景目标的粗糙相对距离,重点得到了退化模型中反映视线路径非均匀性的比例因子项,进而得到了成像路径中的大气透过率,最后利用得到的这些参量通过非均匀路径退化模型的逆过程对降质图像进行复原.实验结果表明,复原算法对实际采集得到的户外自然退化图像复原效果较好.
A new method for the restoration of degraded images in inhornogeneous atmosphere was proposed using the opti- cal model of image degradation in inhomogeneous path. Firstly, Sky radiances at observer corresponding to the slant directions of each object in image were estimated. Then,based on the prior knowledge of dark channel,the rough relative distances of scene ob- jects in image were estimated approximately, and as a key point, the ratio factor which reflects the inhomogeneous property of visual path in the degradation model was obtained, and subsequently atmospheric transmittance of imaging path was computed. Finally, us- ing these parameters computed above,the degraded image can be restored by the inverse process of the optical degradation model. The experimental results show that the new algorithm is effective for actual outdoor degraded images.