Title :
Blur identification with assumption validation for sensor-based video reconstruction and its implementation on field programmable gate array
Author :
Angelopoulou, Maria E. ; Bouganis, Christos-Savvas ; Cheung, Peter Y. K.
Author_Institution :
Dept. of Electr. & Electron. Eng., Imperial Coll. London, London, UK
fDate :
7/1/2011 12:00:00 AM
Abstract :
Restoration methods, such as super-resolution (SR), largely depend on the accuracy of the point spread function (PSF). PSF estimation is an ill-posed problem, and a linear and uniform motion is often assumed. In real-life systems, this may deviate significantly from the actual motion, impairing subsequent restoration. To address the above, this work proposes a dynamically configurable imaging system that combines algorithmic video enhancement, field programmable gate array (FPGA)-based video processing and adaptive image sensor technology. Specifically, a joint blur identification and validation (BIV) scheme is proposed, which validates the initial linear and uniform motion assumption. For the cases that significantly deviate from that assumption, the real-time reconfiguration property of an adaptive image sensor is utilised, and the sensor is locally reconfigured to larger pixels that produce higher frame-rate samples with reduced blur. Results demonstrate that once the sensor reconfiguration gives rise to a valid motion assumption, highly accurate PSFs are estimated, resulting in improved SR reconstruction quality. To enable real-time reconstruction, an FPGA-based BIV architecture is proposed. The system´s throughput is significantly higher than 25 fps, for frame sizes up to 1024 × 1024, and its performance is robust to noise for signal-to-noise ratio (SNR) as low as 20 dB.
Keywords :
field programmable gate arrays; image enhancement; image motion analysis; image reconstruction; image sensors; adaptive image sensor technology; algorithmic video enhancement; autocorrelation-based blur identification framework; field programmable gate array; high-throughput hardware architecture; imaging techniques; improved SR reconstruction quality; joint blur identification and validation scheme; passive cameras; point spread function; sensor-based video reconstruction method; signal-to-noise ratio; system throughput;
Journal_Title :
Computers & Digital Techniques, IET
DOI :
10.1049/iet-cdt.2009.0053