Image enhancement algorithm for tunnel construction scenes

Tunnel images are affected by the shooting environment, and there are problems such as uneven light distribution, local occlusion, and more noise, etc. Aiming at the overexposure and distortion of the existing image enhancement algorithms in the optimisation process, we propose a tunnel image enhancement algorithm DNO-SCI (denoising and overexposure suppression based Self- Calibrated illumination). Firstly, based on the SCI model, a noise suppression module based on a priori knowledge is added to effectively suppress the noise of SCI after low-light enhancement. Secondly, overexposure suppression is guided through the Y channel, and finally a lightweight self-calibrated tunnel construction image enhancement algorithm is proposed in combination with depth-separable convolution. Experimental results demonstrate that the proposed image enhancement algorithm can effectively enhance tunnel construction images with uneven brightness and suppress local overexposure.