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Single image enhancement using dual boundaries

The images captured from environment often suffer from low contrast and visual quality due to the bad imaging conditions like low light or haze weather. Many methods have been proposed based on traditional image enhancement models including dehazing model and Retinex model typically. However, their scopes are limited and specific. In this paper, we propose a simple but effective method to enhance images contrast and keep the good visual quality. By observing the traditional image enhancement models including dehazing model and Retinex model, a general normalized model is proposed. To preserve the image details and control the brightness, we introduce dual boundaries called the dark and bright boundary to handle the low light and high light condition. After getting the dark and bright boundary, the images are enhanced accordingly. Experiments show our method can be applied in many bad imaging conditions and keep good performances.