Graduate Institute of Communication Engineering, National Taiwan University, Taipei 10617, Taiwan, ROC.
IEEE Trans Image Process. 2010 Oct;19(10):2749-60. doi: 10.1109/TIP.2010.2050626. Epub 2010 May 18.
In this paper, we present a system for estimating the shadow field from a single natural image. Unlike previous works that require extensive user assistance, our system only needs the user to roughly specify the shadow boundary with a broad brush. As the user finishes drawing a stroke, the system starts to estimate the shadow field around the stroke and generates pretty accurate result even if the underlying surface is highly textured. We also propose an optimization scheme to propagate the estimated shadow field to the entire image, achieving a further reduction of user effort required for the system. The shadow field estimated by our system can be used to seamlessly remove the shadow from the image. It is also useful for many shadow editing tasks such as pasting an object's shadow from one image to another. Experimental results on a variety of photos are provided to show the effectiveness of the proposed system.
在本文中，我们提出了一种从单张自然图像估计阴影场的系统。与之前需要大量用户辅助的工作不同，我们的系统只需要用户用宽笔粗略地指定阴影边界。当用户完成一笔绘制时，系统开始估计笔触周围的阴影场，并生成非常准确的结果，即使基础表面高度纹理化也是如此。我们还提出了一种优化方案，将估计的阴影场传播到整个图像，进一步减少系统所需的用户工作量。我们系统估计的阴影场可用于从图像中无缝去除阴影。它还可用于许多阴影编辑任务，例如将一个物体的阴影从一张图像粘贴到另一张图像。提供了各种照片的实验结果，以展示所提出系统的有效性。
