TY - GEN
T1 - Spatially varying radiometric calibration for camera-display messaging
AU - Yuan, Wenjia
AU - Dana, Kristin J.
AU - Ashok, Ashwin
AU - Gruteser, Marco
AU - Mandayam, Narayan
PY - 2013
Y1 - 2013
N2 - Modern society has ubiquitous electronic displays including billboards, signage and kiosks. The concurrent prevalence of handheld cameras creates a novel opportunity to use cameras and displays as communication channels. The electronic display in this channel serves a twofold purpose: to display an image to humans while simultaneously transmitting hidden bits for decoding by a camera. Unlike standard digital watermarking, the message recovery in camera-display systems requires physics-based modeling of image formation in order to optically communicate hidden messages in real world scenes. By modeling the photometry of the system using a camera-display transfer function (CDTF), we show that this function depends on camera pose and varies spatially over the display.We devise a radiometric calibration to handle the nonlinearities of both the display and the camera, and we use this method for recovering video messages hidden within display images. Results are for 9 different display-camera systems for messages with 4500 bits. Message accuracy improves significantly with calibration and we achieve accuracy near 99% in our experiments, independent of the type of camera or display used.
AB - Modern society has ubiquitous electronic displays including billboards, signage and kiosks. The concurrent prevalence of handheld cameras creates a novel opportunity to use cameras and displays as communication channels. The electronic display in this channel serves a twofold purpose: to display an image to humans while simultaneously transmitting hidden bits for decoding by a camera. Unlike standard digital watermarking, the message recovery in camera-display systems requires physics-based modeling of image formation in order to optically communicate hidden messages in real world scenes. By modeling the photometry of the system using a camera-display transfer function (CDTF), we show that this function depends on camera pose and varies spatially over the display.We devise a radiometric calibration to handle the nonlinearities of both the display and the camera, and we use this method for recovering video messages hidden within display images. Results are for 9 different display-camera systems for messages with 4500 bits. Message accuracy improves significantly with calibration and we achieve accuracy near 99% in our experiments, independent of the type of camera or display used.
KW - Convex optimization
KW - Photometric modeling
KW - Radiometric calibration
KW - Spatially variations
UR - https://www.scopus.com/pages/publications/84897708031
UR - https://www.scopus.com/pages/publications/84897708031#tab=citedBy
U2 - 10.1109/GlobalSIP.2013.6737003
DO - 10.1109/GlobalSIP.2013.6737003
M3 - Conference contribution
AN - SCOPUS:84897708031
SN - 9781479902484
T3 - 2013 IEEE Global Conference on Signal and Information Processing, GlobalSIP 2013 - Proceedings
SP - 763
EP - 766
BT - 2013 IEEE Global Conference on Signal and Information Processing, GlobalSIP 2013 - Proceedings
T2 - 2013 1st IEEE Global Conference on Signal and Information Processing, GlobalSIP 2013
Y2 - 3 December 2013 through 5 December 2013
ER -