IMAGE UNMIXING SUCCESS ESTIMATION IN SPATIALLY VARYING SYSTEMS Ron Gaizman and Yehoshua Y. Zeevi, Department of Electrical Engineering, Technion, Haifa, Israel. 1
IMAGE UNMIXING SUCCESS ESTIMATION IN
SPATIALLY VARYING SYSTEMS
Ron Gaizman and Yehoshua Y. Zeevi,Department of Electrical Engineering, Technion,
Haifa, Israel.
1
• The problem of recovering source signals from mixtures with only limited knowledge of the mixing process.
• Motivation: Speech signals separation, Image reflection unmixing, Medical Signals Anaysis (MRI, ECG), Communication signals unmixing,…
• Example: “Cocktail party problem”
Introduction
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Introduction
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Introduction
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Stage 1:Estimate based on sparseness of the data.
Stage 2:Use in order to estimate .H S
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R.Kaftory, Y.Zeevi 2009
SSCA( Staged Sparse Component Analysis )
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r1 smooth by gaussian kernal with =0.040241
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Stage 1:
Non-Sparse signals Sparsify
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Signals Estimation
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ˆˆ ˆ ˆargmin RegS
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Success Estimation Method (SEM)
* Function Demands:
- Local Minima when
- Smooth, Convex around true parameters.
* Known Methods demand prior knowledge :
- Signals independence on one another ( ).
- Signals sparseness on some domain.
( ) 0.20.3
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A.Achtenberg Thesis 2011
Proposed Success Estimation Method(SEM)
Use additional knowledge of active set coefficients to estimate success.
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Proposed Success Estimation Method
Success Estimation Methods (SEM)
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- Success versus deviation in mixing system parameters estimation.- Other methods do not satisfy function demands.
Proposed SEM
Feedback Approach to Signal Estimation
Sparse Representation
System Model Estimation
Sources Estimation
Separation Success
Estimation
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Feedback Approach : An Example
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s1 gal (lsqlin),MSE=0.00026189, SNR=12.1468[dB]
s2 gal (lsqlin),MSE=0.00023082, SNR=12.4588[dB]
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s2 gal-s
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Original Signals Mixtures Estimated Signals using SSCA
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Optimization of success estimation function.
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Success Optimization using Q Newton
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Feedback Approach : An Example
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Feedback Approach : An Example
Without Feedback With Feedback
Summary
• Staged Sparse Component Analysis Method.
• Success Estimation Method For Signal and Image un-mixing.
• Feedback Approach for improving Sources Reconstruction.
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The End…
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Mixing kernels
• Instantaneous time/space invariant
• Instantaneous time/space variant
• Attenuation and shift time/space variant
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Sparsification
• Commutative
• One ‘Active’ Source
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Proposed Success Estimation Method
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𝑇𝑖𝑗 𝜉
Not Sparse ? Sparsify
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• Single path spatial distortion system
-> SIFT (for spatial transform)
Model 1 matches:314 (/469) SIFT matches
Model 2 matches:73 (/469) SIFT matches
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aligned
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Not Sparse ? Sparsify
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• Single path spatial distortion system
-> SIFT (for spatial transform) + Alignment
z1
z2 aligned
Not Sparse ? Sparsify
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• Single path spatial distortion system
-> SIFT (for spatial transform) + Alignment + Wavelet Transform (For attenuation model)
50
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50 100 150 200 250 300 350 400 450 500
#points=9511
X
Y
100200
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50050 100 150 200 250 300 350 400 450 500
0.4
0.6
0.8
1
1.2
1.4
1.6
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2
2.2
Y
X
All Points: #= 9579
r
Outliers, #points=5489
Model #1 #points=4090
Estimated Model #1
True Model #1