David Lindell, a graduate student in electrical engineering at Stanford University, donned a high visibility tracksuit and got to work, stretching, pacing and hopping across an empty room.
Through a camera aimed away from Lindell - at what appeared to be a blank wall - his colleagues could watch his every move.
That's because, hidden to the naked eye, he was being scanned by a high powered laser and the single particles of light he reflected onto the walls around him were captured and reconstructed by the camera's advanced sensors and processing algorithm.
The camera system Lindell tested, which the researchers are presenting at the SIGGRAPH 2019 conference Aug. 1, builds upon previous around-the-corner cameras this team developed.
But real-world objects, including shiny cars, fall outside these categories, so this system can handle light bouncing off a range of surfaces, including disco balls, books and intricately textured statues.
By the time the laser light reaches the camera only specks remain, but the sensor captures every one, sending it along to a highly efficient algorithm, also developed by this team, that untangles these echoes of light to decipher the hidden tableau.