基于相对梯度正则化的Retinex变分模型及其应用

Variational Retinex model based on an extension of TV regularization with relative gradient and its application

针对全变分Retinex模型使用反射分量的全变分作为正则项存在的不足,引入相对梯度并构建扩展的全变分正则项,提出一种新的Retinex变分模型。相比于变分Retinex模型、全变分Retinex模型,该模型获取的照度分量更加光滑,同时反射分量能够分辨更多结构信息和细节要素。进而,提出一种综合考虑照度分量和反射分量的图像增强模型。通过调整模型参数,可有效应用于高动态范围图像色调映射、非均匀照度增强等图像处理领域。与其他算法的对比显示,该图像增强模型能够有效处理上述问题并取得较好的效果。

In view of the shortcomings of the total variational Retinex model which use the total variation （TV） of the reflection as the regularization. An extension of TV regularization with the concept of relative gradient was introduced and finally a new variational Retinex model was proposed. Compared with variational Retinex and total variational Reti-nex model, the proposed model can preserve the estimated reflectance with more details as well as the more smoothed il-lumination. Further, a new integrated image enhancement model considering both the illumination and the reflectance was proposed. By adjusting the model parameters, the proposed model can be effectively applied to high dynamic range image tone mapping and non-uniform illumination enhancement. Compared with other algorithms, the proposed model can better handle the above image enhancement problems.