<p>Underwater images suffer from issues such as haze and color distortion caused by complex environmental factors. An underwater image enhancement method is introduced, which is based on color-line model and color correction. The accuracy of estimating background light and transmission is key for underwater image enhancement. Firstly, the background light candidate regions are estimated using image blocking and minimum unary gray entropy. The background light is estimated by separating the background using a threshold formula in the candidate regions. Then, a restarted accelerated convex optimization method is developed to estimate transmission, which is based on the minimum optimization problem between the color-line and the background light. The dehazed image is obtained using the simplified imaging model. Finally, the color correction technique is employed to enhance the visual quality of the dehazed images. The effectiveness of the proposed method is verified through experiments in four aspects, including qualitative analysis, quantitative analysis, color accuracy analysis and application analysis.</p>