基于图像序列的超分辨率重建,是利用同一场景的多幅低分辨率图像重建一幅高分辨率图像,其实现过程可分为两个步骤:首先,利用亚像素图像配准技术将所有的低分辨率图像配准;然后,利用配准的多幅图像重建一幅高分辨率图像.针对配准这一问题,提出一种新颖的图像亚像素配准方法.新方法先将Haar小波分解出的低频子图应用频域Vandewalle方法进行初步配准,然后结合空域Keren改进方法进一步提高配准精度,同时利用金字塔在不同层上分别实现亚像素配准,并逐层累加配准结果.实验结果表明,即使在较大的平移和旋转情况下,相比只有空域Keren改进方法和只有频域Vandewalle方法,该方法的配准精度和超分辨率重建效果都得到明显提高.
Image super-resolution reconstruction is a process of reconstructing a high-resolution image from a set of low-resolution images of the same scene. It can be achieved in two steps : registering all low-resolution images at sub-pixel accuracy, and using the registered low-resolution images to reconstruct a super-resolution image. This paper proposes a novel method of sub-pixel image registration. Preliminary registration is done using the Vandewalle' s method with only the approximation of sub-images in the Haar domain. Fine registration is achieved using an improved Keren' s method. Registration is then conducted in a pyramid fashion, and the registered results of all layers are accumulated. In terms of registration accuracy and reconstruction quality, experiments demonstrate that the proposed method has better performance as compared to the improved Keren' s method and Vanderwalle' s method even though the shift and rotation are large.