Separation of Convolutive Image Mixtures Technion, Dept. EE Yoav Y. Schechner Joint studies with: Nahum Kiryati & Ronen Basri; Sarit Shwartz & Michael Zibulevsky 1
Separation of Convolved Images window camera 35 Schechner, Kiryati & Basri, Separation of transparent layers using focus
“far” scene camera “close” scene Convolutive Mixture 36 Schechner, Kiryati & Basri, Separation of transparent layers using focus
Optical Sectioning (microscopy) objects in spaceraw frames 37
Transparent Layers For each frequency Instabilities as Problematic at low frequencies Schechner, Kiryati & Basri, Separation of transparent layers using focus
Processed images l far l close Acquired images raw far raw close Schechner, Kiryati & Basri, Separation of transparent layers using focus
W separate A mix Independent Sources Linear Mixture Unknown Known Blind Source Separation
A mix & blur Convolutive Mixtures Shwartz, Schechner & Zibulevsky, Convolutive Mixtures 41
Separation Optimization W separate Shwartz, Schechner & Zibulevsky, Convolutive Mixtures
Mutual Information of a Convolutive Mixture W separate A mix & blur Shwartz, Schechner & Zibulevsky, Convolutive Mixtures
Separation in the Frequency Domain FFT Shwartz, Schechner & Zibulevsky, Convolutive Mixtures
Problem: No Statistic Ensemble in FT No statistics per frequency Shwartz, Schechner & Zibulevsky, Convolutive Mixtures
Separation by Sub-band Images Shwartz, Schechner & Zibulevsky, Convolutive Mixtures 43
Image Statistics * See for example: Simoncelli (99)
MI of Sparse Sources Parametric PDF MI is not convex in MI is convex in
Scale & Sign Ambiguity Shwartz, Schechner & Zibulevsky, Convolutive Mixture 44 transform inverse transform … imbalance
Permutation Ambiguity Shwartz, Schechner & Zibulevsky, Convolutive Mixture 45 transform inverse transform inverse … crosstalk
Out of Focus Blur See for example: Stokseth (69), Born; Wolf (70), Hecht (87), Mahajan (94), Braat; Dirksen; Janssen (02), Sheppard; Cooper (04).
Parametric Model for Blur Shwartz, Schechner & Zibulevsky, Convolutive Mixtures 46
Parametric Model for the Blur
Simulations of Natural Images
Simulation Blind Estimation Using Ideal kernel + 1% noise Shwartz, Schechner & Zibulevsky, Convolutive Mixtures 47
Experiment Raw images High-pass of raw images Separation results Shwartz, Schechner & Zibulevsky, Convolutive Mixtures 48