Hierarchical Structure from Motion from Endoscopic Video

Abstract

We present a hierarchical approach to structure from motion. This approach uses the notion of frame distance, which we define to be the median image displacement of tracked features. Image pairs with a high frame distance are used to initialise reconstruction, as they are expected to have significant associated camera motion and, therefore, give strong geometric constraints on the reconstruction. Additional frames are then added with progressively smaller frame distances to create denser reconstructions. We demonstrate this technique on endoscopic video, where there is a mix of rapid camera motion and periods where the camera is nearly stationary.