People with colour vision deficiency (CVD) may have difficulty recognising or discriminating colours. To enhance their visual details, some methods have been developed to enhance colour contrast. Recently, researchers realized the importance of preserving naturalness in the processed images to avoid decreasing the quality of vision (QOV) and state-of-the-art image recolouring methods succeeded in realising both contrast enhancement and naturalness preservation by utilising optimisation model. However, the high computational cost of these methods prevents their wide application in daily lives. Moreover, these methods cannot automatically resolve the trade-off between contrast enhancement and naturalness preservation. This paper proposes Optimized Dichromacy Projection (ODP) as a novel high-speed image recolouring technique for dichromacy compensation. ODP achieves both contrast enhancement and naturalness preservation by computing an optimized projection from the colour gamut of normal vision to the colour gamut of dichromacy and can automatically adapt the weight of contrast enhancement and naturalness preservation to the property of individual images. Qualitative, quantitative, and subjective evaluation experiments show that the proposed method can generate images of qualities competitive to the state-of-the-art methods while drastically improving computation time.

患有色觉不足（CVD）的人可能难以识别或区分颜色。为了增强其视觉细节，已开发出一些方法来增强色彩对比度。最近，研究人员意识到在处理后的图像中保持自然度以避免降低视觉质量（QOV）的重要性，而最新的图像重新着色方法通过利用优化模型成功实现了对比度增强和自然度保持。但是，这些方法的高计算成本阻碍了它们在日常生活中的广泛应用。而且，这些方法不能自动解决对比度增强和自然保存之间的折衷。本文提出了优化的双色度投影（ODP）作为一种用于双色度补偿的新型高速图像重新着色技术。ODP通过计算从正常视觉的色域到二色性色域的最佳投影来实现对比度增强和自然保存，并且可以自动调整对比度增强和自然保存的权重以适应单个图像的属性。定性，定量和主观的评估实验表明，所提出的方法可以生成质量与最新方法相当的图像，同时可以大大缩短计算时间。ODP通过计算从正常视觉的色域到二色性色域的最佳投影来实现对比度增强和自然保存，并且可以自动调整对比度增强和自然保存的权重以适应单个图像的属性。定性，定量和主观的评估实验表明，所提出的方法可以生成质量与最新方法相当的图像，同时可以大大缩短计算时间。ODP通过计算从正常视觉的色域到二色性色域的最佳投影来实现对比度增强和自然保存，并且可以自动调整对比度增强和自然保存的权重以适应单个图像的属性。定性，定量和主观的评估实验表明，所提出的方法可以生成质量与最新方法相当的图像，同时可以大大缩短计算时间。