SRA: Fast Removal of General Multipath for ToF Sensors
This addresses a major issue for users of ToF sensors by enabling fast removal of multipath interference, though it appears incremental as it builds on existing optimization techniques.
The paper tackles multipath interference in Time of Flight sensors by introducing Sparse Reflections Analysis (SRA), an algorithm that removes general forms of multipath, including complex and diffuse types, and achieves frame-rate performance, as validated on synthetic and real data.
A major issue with Time of Flight sensors is the presence of multipath interference. We present Sparse Reflections Analysis (SRA), an algorithm for removing this interference which has two main advantages. First, it allows for very general forms of multipath, including interference with three or more paths, diffuse multipath resulting from Lambertian surfaces, and combinations thereof. SRA removes this general multipath with robust techniques based on $L_1$ optimization. Second, due to a novel dimension reduction, we are able to produce a very fast version of SRA, which is able to run at frame rate. Experimental results on both synthetic data with ground truth, as well as real images of challenging scenes, validate the approach.