投影与光照方向一致性的图像篡改检测

Image Tampering Detection by Consistency of Projection and Lighting Direction

针对在自然光照条件下拍摄的图像遭到篡改的情况,提出了一种新的篡改检测方法.光照射到物体上在物体表面会发生漫反射现象,同时会在投影平面上产生阴影,一旦图像遭到篡改很难保持这些自然特征的一致性.因此,根据物体表面估计出的光照方向与投射阴影得到的光源区域的一致性,不仅可以检测有多个物体的篡改图像,还可以检测出只有1个物体的图像是否被篡改.

A new forgery detection scheme is proposed in case of modification of images formed naturally. Illuminating an object leads to make diffuse refection on surface of the object, its shadow appears in the projection plane. Once images are tampered, it is difficult to maintain the consistency of these natural features. Therefore, the uniformity between the direction of light estimated with an object in a photo- graphic and the area of the light direction on the basis of cast shadow, will not effectively work for a de- tected image of multiple objects, but determine if an image with only one is tampered or not.