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Jitter Camera: High Resolution Video from a Low Resolution Detector. Moshe Ben-Ezra, Assaf Zomet and Shree K. Nayar IEEE CVPR Conference June 2004, Washington DC, USA. Plasma Display Resolution 1366x768. MiniDV Camera. Resolution: 720x480. Digital Camera. Resolution: 2592x1944.
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Jitter Camera: High Resolution Video from a Low Resolution Detector Moshe Ben-Ezra, Assaf Zomet and Shree K. Nayar IEEE CVPR Conference June 2004, Washington DC, USA
Plasma Display Resolution 1366x768 MiniDV Camera. Resolution: 720x480 Digital Camera. Resolution: 2592x1944 Video Resolution
Fundamental Resolution Tradeoff Hi-resolution still Camera Conventional video camera 3M 2048x1536 330K 720x480 3 Temporal resolution (fps) 30 130 Spatial resolution (pixels)
Super-Resolution Shechtman, Caspi, and Irani ECCV2002 Zomet and S. Peleg. ICIP2000 Baker and Kanade. CVPR2000 Chiang and Boult, IVC2000 Capeland, Zisserman ICPR2000 Elad and Feuer IP1997 Irani and Peleg GMIP1996 Super-Resolution Sequence taken by a moving camera High-Resolution computed image
Super Resolution y = (D G)x + z Blurring Op. Noise All Sampled Images Decimation Hi Res. Image
Effect of Motion Blur on Super-Resolution Input: No Motion Blur Super-Resolution Result Input : With Motion Blur (known) Super-Resolution Result
Input Images High-Resolution Image Blur & Decimation Noise (Quantization) Volume of Solutions 1/det(A) Quantifying The Affect of Motion Blur • Empirical tests: RMS error. • Volume of Solutions (Linear Model): Baker and Kanade
How Bad is Motion Blur for Super-Resolution? 18 0 1 2 3 4 5 RMS Error After Super-Resolution Space of Super-Resolution Solutions 0 1 2 3 4 5 Motion blur in pixels Motion blur in pixels
Avoid Motion Blur using Jitter Sampling Spatial Jitter Sampling Time Time Space Space Conventional Sampling
The Jitter Camera Lens Detector Micro-actuator
The Jitter Camera Lens Detector Micro-actuator Detector is a light weight device! Jitter is instantaneous and synchronous
Computer Controlled Y Micro-Actuator Computer Controlled X Micro-Actuator Lens Board Camera
Jitter Mechanism Accuracy 1μm Y Pixels X Pixels Actual locations. Desired locations.
Result: Resolution Chart Four Images from the Jitter Camera Super-Resolution Image
Result: Color DeMosaicing and Super-Resolution Super-Resolution 1 (out of 4) Jitter camera Image
Jitter Video (Stabilized) How can we handle dynamic scenes?
Adaptive Super-Resolution for Dynamic Scenes Static blocks: 4 frames used. Occlusions: 1 frame used. Moving object: 2 - 4 frames used
Adaptive Super-Resolution Algorithm Estimate the aliasing error ‘’ (stdv)for each block Ikin I. Compute robust block matching between all pairs {I}{I1,2,3}. Use ‘’ as a scale factor for an M-Estimatorerror function. For each block Iktry tofind 3 matching blocks {Ix}k, s.t. : SSD(Ik, {Ix}k)-0.5< 3 {Ix}k are temporally closest to Ik (smallest x) Apply super-resolution to the selected blocks. The algorithm degrades gradually from 4-frames super-resolution to a single frame interpolation and deblurring. I-3 I-2 I-1 I I+1 I+2 I+3
Scale Estimate Mean 6.4, Stdv 14 Mean 7.5, Stdv 16 Mean 8.6, Stdv 17 Low Res - Hi-Res Aliasing Error (Simulated) Mean 10.5, Stdv 27 Mean 15.2, Stdv 30 Mean 17.7, Stdv 33 Low Res 2nd derivative (Simulated)