AH-HIS: An adaptive pseudo-color enhancement method for high grayscale X-ray film weld images

Aiming at the problems of poor adaptability and insufficient robustness of existing high-grayscale image pseudo-color enhancement methods. An adaptive pseudo-color enhancement algorithm for high-grayscale X-ray film weld seam images based on Hue, Saturation and Brightness color space is proposed. Firstly, a pixel self-transformation is performed on the original high-grayscale X-ray weld image. And assign the converted B, G and R values to the H, I, and S components in the HIS color space respectively. Secondly, because of the poor universality of the algorithm and the difficult dynamic adjustment of the HIS color space. The power adjustment and the grayscale correction is integrated into the constructed high gray scale HIS pixel self-transformation function, and an adaptive gray scale correction algorithm based on BP neural network is proposed and designed. Finally, the HIS component is converted to the RGB color space for display. The experimental results show that the pseudo-color enhancement method proposed in this paper can effectively improve the recognition of image defects. In the processing of low-contrast images, compared with the HIS algorithm used for low-grayscale weld ray images, all indicators have a better result. Among them, the entropy increased by 1.216%, contrast increased by nearly 2 times, image clarity index IL-NIQE increased by nearly 39.171%, and NIQE increased by 8.79%.