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JBE, vol. 27, no. 5, pp.812-815, September, 2022


Image Enhancement based on Piece-wise Linear Enhancement Curves for Improved Visibility under Sunlight

Junmin Lee and Byung Cheol Song

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Images displayed on a digital devices under the sunlight are generally perceived to be darker than the original images, which leads to a decrease in visibility. For better visibility, global luminance compensation or tone mapping adaptive to ambient lighting is required. However, the existing methods have limitations in chrominance compensation and are difficult to use in real world due to their heavy computational cost. To solve these problems, this paper propose a piece-wise linear curves (PLECs)-based image enhancement method to improve both luminance and chrominance. At this time, PLECs are regressed through deep learning and implemented in the form of a lookup table to real-time operation. Experimental results show that the proposed method has better visibility compared to the original image with low computational cost.

Keyword: ambient-lighting, visibility improvement, piece-wise linear curve, look up table

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