Dark Channel: The Devil is in the Details
Mingzhu Zhu, Bingwei He, Jiantao Liu, Liwei Zhang · IEEE Signal Processing Letters · 2019
Dark channel prior is a highly valued theory mostly used in the area of haze removal. It reveals the wide existence of pixels with very small channel. However, the definition is in a decorated way that relies on the concept of dark channel. The dark channel works like an image domain wherein non-sky regions of clear outdoor images are close to zero. In this letter we show that, such a concept is unnecessary and misleading, and can be improved by using a more basic concept named dark pixel. A novel transmission estimation method based on finding dark pixels is proposed. The method is concise and easy to understand. In comparisons with state-of-the-art methods, our method shows significant improvements on both transmission estimation and haze removal results.