Efficient homography-based video visualization for wireless capsule endoscopy

Wireless capsule endoscopy (WCE) is performed by a swallowable pill capsule equipped with a camera wirelessly transmitting color video frames to an external receiver. The resulting video consists usually of several thousands of frames and its visual examination requires hours of endoscopists' undivided attention. In this paper we propose a novel visualization approach for WCE which enables faster examination of the endoscopic video, while providing a broader field of view. This is achieved by an algorithm that iteratively samples clusters of consecutive frames from the original video. The frames of each cluster are geometrically transformed, so as to generate a seamless collage subsequently projected into a new frame without any information loss. The new frames compose a new WCE video with a smaller number of frames. The video frame collage is based on homography matrix estimation from frame correspondences. The experiments show that the length of the WCE video, and therefore the reading times required can be significantly reduced.