Combining highlight removal and low-light image enhancement technique for HDR-like image generation

• Published in: IET image processing Vol. 14; no. 9; pp. 1851 - 1861
• Main Authors: Saha, Rappy, Pratim Banik, Partha, Sen Gupta, Shantanu, Kim, Ki-Doo
• Format: Journal Article
• Language: English
• Published: The Institution of Engineering and Technology 20.07.2020
• Subjects: actual colour; conventional image sensors; HDR‐like; high dynamic range‐like images; highlight areas; highlight phenomena limit colour richness; highlight pixels; highlight removal; image colour analysis; image enhancement; image processing; image recognition; image sensors; low dynamic range image; low‐light enhancement technique; low‐light image enhancement technique; Research Article; rich colours; single LDR image; image processing; actual colour; single LDR image; low-light image enhancement technique; highlight pixels; high dynamic range-like images; highlight areas; image sensors; highlight removal; image enhancement; low dynamic range image; HDR-like; rich colours; conventional image sensors; highlight phenomena limit colour richness; image colour analysis; low-light enhancement technique; image recognition
• ISSN: 1751-9659; 1751-9667; 1751-9667
• DOI: 10.1049/iet-ipr.2019.1099

Low dynamic range (LDR) image may contain low-light and highlight areas due to the limitations of the dynamic range of conventional image sensors. Low-light and highlight phenomena limit colour richness and visibility of objects in an image. Therefore, it can cause a reduction in the quality of images and a loss in accuracy in the application of image recognition. To overcome this, high dynamic range (HDR)-like images have been developed with rich colours such as those seen by the human eye. In this study, the authors propose a method to obtain an HDR-like image from a single LDR image by removing the specular component from highlight pixels as well as strengthening the actual colour. Next, they select low-light image enhancement via illumination map estimation as a low-light enhancement technique by showing the comparison with gamma-based expansion operator. They evaluate their HDR-like output images with non-reference and full-reference metrics. They show the comparison of their proposed method with six other methods. Besides, visually, their proposed method delivers more pleasing output than the output of other competitive methods.