Study of avalanche fluctuations and energy resolution with an InGrid-TimePix detector
Jitter Camera: High Resolution Video from a Low Resolution Detector
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Transcript of Jitter Camera: High Resolution Video from a Low Resolution Detector
Jitter Camera: High Resolution Video from a Low
Resolution Detector
Moshe Ben-Ezra, Assaf Zomet and Shree K. Nayar
IEEE CVPR ConferenceJune 2004, Washington DC, USA
Video Resolution
MiniDV Camera. Resolution: 720x480
Digital Camera. Resolution: 2592x1944
Plasma DisplayResolution 1366x768
Fundamental Resolution Tradeoff
Spatial resolution (pixels)
Tem
pora
l res
olut
ion
(fps
)
30
330K720x480
Conventional video camera
130
3
3M2048x1536
Hi-resolution still Camera
Super-Resolution
Sequence taken by a moving camera
High-Resolution computed image
Super-Resolution
Shechtman, Caspi, and Irani ECCV2002Zomet and S. Peleg. ICIP2000Baker and Kanade. CVPR2000Chiang and Boult, IVC2000
Capeland, Zisserman ICPR2000Elad and Feuer IP1997 Irani and Peleg GMIP1996
Super Resolution
All SampledImages
y = (D G)x + z
Decimation
Blurring Op.
Hi Res. Image
Noise
Motion Blur Hurts Us Again!
Capture Images without Motion Blur
Effect of Motion Blur on Super-Resolution
Input: No Motion Blur Super-Resolution Result
Input : With Motion Blur (known) Super-Resolution Result
Quantifying The Affect of Motion Blur
Empirical tests: RMS error. Volume of Solutions (Linear Model):
y Ax z x A 1y A 1z
High-ResolutionImage
Noise (Quantization)
InputImages
Volume of Solutions 1/det(A)
Blur &Decimation
Baker and Kanade
How Bad is Motion Blur for Super-Resolution?
Space of Super-Resolution Solutions
0 1 2 3 4 5
Motion blur in pixels
RMS Error After Super-Resolution
0 1 2 3 4 5
18
Motion blur in pixels
Avoid Motion Blur using Jitter Sampling
Conventional Sampling
Time
Space
Spatial Jitter Sampling
Time
Space
The Jitter CameraLens Detector
Micro-actuator
The Jitter CameraLens Detector
Micro-actuator
Detector is a light weight device!
Jitter is instantaneous and synchronous
Computer ControlledX Micro-Actuator
Computer ControlledY Micro-Actuator
Board Camera
Lens
1μm X Pixels
Y P
ixel
s
Jitter Mechanism Accuracy
Desired locations. Actual locations.
Result: Resolution Chart
Super-Resolution ImageFour Images fromthe Jitter Camera
Result: Color DeMosaicing and Super-Resolution
1 (out of 4) Jitter camera Image Super-Resolution
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
I-3 I-2 I-1 I I+1 I+2 I+3
Adaptive Super-Resolution Algorithm
1. Estimate the aliasing error ‘’ (stdv) for each block Ik in I.2. Compute robust block matching between all pairs {I}{I1,2,3}. Use
‘’ as a scale factor for an M-Estimator error function.
3. For each block Ik try to find 3 matching blocks {Ix}k, s.t. : a) SSD(Ik, {Ix}k)-0.5 < 3b) {Ix}k are temporally closest to Ik (smallest x)
4. Apply super-resolution to the selected blocks.
The algorithm degrades gradually from 4-frames super-resolution to a single frame interpolation and deblurring.
Scale EstimateMean 6.4, Stdv 14
Mean 10.5, Stdv 27
Mean 7.5, Stdv 16
Mean 15.2, Stdv 30
Mean 8.6, Stdv 17
Mean 17.7, Stdv 33
Low Res - Hi-ResAliasing Error(Simulated)
Low Res2nd derivative(Simulated)