1. A computer-implemented method comprising: receiving, by one or more computing devices, an initialization request for a still image capture mode; after receiving the request to initialize the still image capture mode, automatically beginning, by the one or more computing devices, to capture a video including a plurality of image frames; tracking, by the one or more computing devices, features between a first image frame of the video and each of the other image frames of the video; generating, by the one or more computing devices, a set of 3D points corresponding to the tracked features using a set of assumptions, the set of assumptions including a first assumption that there is no rotation between the plurality of image frames of the video and a second assumption that there is no translation between the plurality of image frames of the video; and generating a depth map of a scene, by the one or more computing devices, based at least in part on the set of 3D points.