Although image completion has been used in many image filling and editing problems for a long time, it is rarely applied in the scenario regarding the perspective effect which is demonstrated largely in the design of urban architectures. Thus this paper proposes a method to capture the perspective information automatically based on a single image and employs it to image completion tasks effectively. Actually it is difficult to automatize the extraction from only a single image, but it has been observed that architectures usually contain plenty of repetitions and symmetries which could be described through periodicity. Therefore, our approach first determines the initial vanishing points through the cascaded hough transformation. Then, a refinement scheme based on SIFT feature matching is proposed to obtain the accurate vanishing points. At last, a good perspective mesh is generated from the geometry calculation. The experiments show that this method could be used to automatically extract perspective information from a single image and recover the image in a visually plausible way