Vision for road inspection

Road surface inspection in cities is for the most part, a task performed manually. Being a subjective and labor intensive process, it is an ideal candidate for automation. We propose a solution based on computer vision and data-driven methods to detect distress on the road surface. Our method works on images collected from a camera mounted on the windshield of a vehicle. We use an automatic procedure to select images suitable for inspection based on lighting and weather conditions. From the selected data we segment the ground plane and use texture, color and location information to detect the presence of pavement distress. We describe an over-segmentation algorithm that identifies coherent image regions not just in terms of color, but also texture. We also discuss the problem of learning from unreliable human-annotations and propose using a weakly supervised learning algorithm (Multiple Instance Learning) to train a classifier. We present results from experiments comparing the performance of this approach against multiple individual human labelers, with the ground-truth labels obtained from an ensemble of other human labelers. Finally, we show results of pavement distress scores computed using our method over a subset of a citywide road network.