Abstract:

In the smoky, foggy, hazy and other harsh outdoor conditions, scene image captured is severely degraded by the scattering of atmospheric particles. Based on atmospheric scattering model, the degraded image needs a white balance operation to simplify the atmospheric scattering model; then, a new nonlinear spatial filtering algorithm is put forward to estimate the rough luminance of the sky, and joint bilateral filter is introduced to further refine the luminance of the sky. Finally, image is restored by using tone mapping. The complexity of the proposed algorithm is only a linear function of the input image pixels numbers, and this allows a very fast implementation. Experiments show that the proposed algorithm can effectively restore the fogdegraded images. With this algorithm, the images is restored with more natural, realistic, and higher-definition.

Key words: image defogging, joint bilateral filter, atmospheric scattering model, white balance, tone mapping