Analyzing Pathfinder data using virtual reality and superresolved imaging

The Mars Pathfinder mission used a unique capability to rapidly generate an d interactively display three-dimensional (3-D) photorealistic virtual real ity (VR) models of the Martian surface. An interactive terrain visualizatio n system creates and renders digital terrain models produced from stereo im ages taken by the Imager for Mars Pathfinder (IMP) camera. The stereo pipel ine, an automated machine vision algorithm, correlates features between the left and right images to determine their disparity and computes the corres ponding positions using the known camera geometry. These positions are conn ected to form a polygonal mesh upon which IMP images are overlaid as textur es. During the Pathfinder mission, VR models were produced and displayed al most as fast as images were received. The VR models were viewed using MarsM ap, an interface that allows the model to be viewed from any perspective dr iven by a standard three-button computer mouse. MarsMap incorporates graphi cal representations of the lander and rover and the sequence and spatial lo cations at which rover data were taken. Graphical models of the rover were placed in the model to indicate the rover position at the end of each day o f the mission. Images taken by Sojourner cameras are projected into the mod el as 2-D "billboards" to show their proper perspective. Distance and angle measurements can be made on features viewed in the model using a mouse-dri ven 3-D cursor and a point-and-click interface. MarsMap was used to assist with archiving and planning Sojourner activities and to make detailed measu rements of surface features such as wind streaks and rock size and orientat ion that are difficult to perform using 2-D images. Superresolution image p rocessing is a computational method for improving image resolution by a fac tor of 1/2 by combining n independent images. This technique was used on Pa thfinder to obtain better resolved images of Martian surface features. We s how results from superresolving IMP camera images of six targets including near- and far-field objects and discuss how the resolution improvement aids interpretation. Similar flood deposits can be seen on both of the Twin Pea ks that cannot be resolved in raw images. Millimeter-sized pits are resolve d on the rocks Wedge and Halfdome. Other rocks at the Pathfinder site exhib it fine-scale layering that is otherwise invisible. Use of the method resul ted in the probable discovery of an artifact of intelligent life on Mars: a part of the Pathfinder spacecraft.