Improving color constancy by discounting the variation of camera spectral sensitivity
Improving color constancy by discounting the variation of camera spectral sensitivity
复制标题
通过减少相机光谱灵敏度的变化来提高颜色稳定性
DOI：
10.1364/josaa.34.001448
复制
发表时间：
2017-08-01
影响因子：
1.9
通讯作者：
Li, Yong-Jie
中科院分区：
文献类型：
--
作者：
Gao, Shao-Bing;Zhang, Ming;Li, Yong-Jie
同时考虑场景光源和相机光谱灵敏度的影响，从有颜色偏差的图像中恢复真实场景颜色是一个不适定问题。大多数颜色恒常性（CC）模型被设计为首先估计光源颜色，然后从颜色偏置图像中去除光源颜色以获得在白色光下拍摄的图像，而没有显式地考虑CSS对CC的影响。本文首先研究了在基于数据集间的CC（inter-CC）中出现的CSS对照明估计的影响，即，在一个数据集上训练CC模型，然后在由不同CSS捕获的另一个数据集上进行测试。我们表明，现有的CC模型之间的CC应用程序的明显退化。然后提出了一种简单的方法来克服这种退化，首先快速学习两个不同的CSS（CSS-1和CSS-2）之间的变换矩阵。然后使用学习的矩阵将在CSS-1下渲染的数据（包括光源地面实况和颜色偏置图像）转换为CSS-2，然后在CSS-2下训练并将CC模型应用于颜色偏置图像，而无需在CSS-2下繁琐地获取训练集。在合成图像和真实的图像上的实验表明，该方法可以明显改善传统CC算法的CC间性能。我们建议，通过考虑CSS效应，它是更有可能获得真正的颜色不变的图像不变的光源和相机传感器的变化。
It is an ill-posed problem to recover the true scene colors from a color biased image by discounting the effects of scene illuminant and camera spectral sensitivity (CSS) at the same time. Most color constancy (CC) models have been designed to first estimate the illuminant color, which is then removed from the color biased image to obtain an image taken under white light, without the explicit consideration of CSS effect on CC. This paper first studies the CSS effect on illuminant estimation arising in the inter-dataset-based CC (inter-CC), i.e., training a CC model on one dataset and then testing on another dataset captured by a distinct CSS. We show the clear degradation of existing CC models for inter-CC application. Then a simple way is proposed to overcome such degradation by first learning quickly a transform matrix between the two distinct CSSs (CSS-1 and CSS-2). The learned matrix is then used to convert the data (including the illuminant ground truth and the color-biased images) rendered under CSS-1 into CSS-2, and then train and apply the CC model on the color-biased images under CSS-2 without the need of burdensome acquiring of the training set under CSS-2. Extensive experiments on synthetic and real images show that our method can clearly improve the inter-CC performance for traditional CC algorithms. We suggest that, by taking the CSS effect into account, it is more likely to obtain the truly color constant images invariant to the changes of both illuminant and camera sensors.