P2C2: Programmable pixel compressive camera for high speed imaging

TitleP2C2: Programmable pixel compressive camera for high speed imaging
Publication TypeConference Papers
Year of Publication2011
AuthorsReddy D, Veeraraghavan A, Chellappa R
Conference Name2011 IEEE Conference on Computer Vision and Pattern Recognition (CVPR)
Date Published2011/06/20/25
ISBN Number978-1-4577-0394-2
KeywordsBrightness, brightness constancy constraint, camera sensor, CAMERAS, compressive video sensing, high speed imaging, high-speed video frames, Image sequences, imaging, imaging architecture, independent shutter, Liquid crystal on silicon, low speed coded video, Modulation, optical flow, P2C2, programmable pixel compressive camera, reconstruction algorithm, sparse representation, Spatial resolution, spatio-temporal redundancies, temporal redundancy, temporal super-resolution, video coding

We describe an imaging architecture for compressive video sensing termed programmable pixel compressive camera (P2C2). P2C2 allows us to capture fast phenomena at frame rates higher than the camera sensor. In P2C2, each pixel has an independent shutter that is modulated at a rate higher than the camera frame-rate. The observed intensity at a pixel is an integration of the incoming light modulated by its specific shutter. We propose a reconstruction algorithm that uses the data from P2C2 along with additional priors about videos to perform temporal super-resolution. We model the spatial redundancy of videos using sparse representations and the temporal redundancy using brightness constancy constraints inferred via optical flow. We show that by modeling such spatio-temporal redundancies in a video volume, one can faithfully recover the underlying high-speed video frames from the observed low speed coded video. The imaging architecture and the reconstruction algorithm allows us to achieve temporal super-resolution without loss in spatial resolution. We implement a prototype of P2C2 using an LCOS modulator and recover several videos at 200 fps using a 25 fps camera.