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Image Deblurring with Optimizations. University of Washington The Chinese University of Hong Kong Adobe Systems, Inc. Qi Shan Leo Jiaya Jia Aseem Agarwala. The Problem. 2. An Example. Previous Work (1). Hardware solutions:. [Ben-Ezra and Nayar 2004]. [Levin et al. 2008].
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Image Deblurring with Optimizations University of Washington The Chinese University of Hong Kong Adobe Systems, Inc. Qi Shan Leo Jiaya Jia Aseem Agarwala
Previous Work (1) Hardware solutions: [Ben-Ezra and Nayar 2004] [Levin et al. 2008] [Raskar et al. 2006] 4
[Jia et al. 2004] [Rav-Acha and Peleg 2005] [Petschnigg et al. 2004] [Yuan et al. 2007] Previous Work (2) Multi-frame solutions: 5
Previous Work (3) Single image solutions: [Fergus et al. 2006] [Jia 2007] [Levin et al. 2007] 6
Most recent work on Single Image Deblurring Qi Shan, Jiaya Jia, and Aseem Agarwala High-Quality Motion Deblurring From a Single Image. SIGGRAPH 2008 Lu Yuan, Jian Sun, Long Quan and Heung-Yeung Shum Progressive Inter-scale and intra-scale Non-blind Image Deconvolution. SIGGRAPH 2008. Joshi, N., Szeliski, R. and Kriegman, D. PSF Estimation using Sharp Edge Prediction, CVPR 2008. A. Levin, Y. Weiss, F. Durand, W. T. Freeman Understanding and evaluating blind deconvolution algorithms. CVPR 2009 Sunghyun Cho and Seungyong Lee, Fast Motion Deblurring. SIGGRAPH ASIA 2009 And many more...
Some take home ideas 1. Using hierarchical approaches to estimate kernel in different scales 2. Realize the importance of strong edges 3. Bilateral filtering to suppress ringing artifacts 4. RL deconvolution is good, but we've got better chioces 5. Stronger prior does a better job 6. Deblurring by assuming spatially variant kernel is a good way to go
Today's topic How to apply natural image statistics, image local smoothness constraints, and kernel sparsity prior in a MAP process Short discussion on 1. the stability of a non-blind deconvolution process 2. noise resistant non-blind deconvolution and denoising
Kernel Statistics exponentially distributed 17
Combining All constraints L f n Two-step iterative optimization • Optimize L • Optimize f 18
Optimization Process Optimize L Idea: separate convolution replace with 19
Optimization Process Optimize L Idea: separate convolution replace with 20
Updating L Adding a new constraint to make Removing terms that are not relevant to An easy quadratic optimization problem with a closed form solution in the frequency domain 21
Updating Removing terms that are not relevant to 22
each only contains a single variable Ψi It is then a set of easy single variable optimization problems 23
Iteration 0 (initialization) 24
Time: about 30 seconds for an 800x600 image Iteration 8 (converge) 25
A comparison RL deconvolution 26
A comparison Our deconvolution 27
Two-step iterative optimization • Optimize L • Optimize f Optimization with a total variation regularization 28
Results 29
Results 30
More results 33
More results 34
Today's topic How to apply natural image statistics, image local smoothness constraints, and kernel sparsity prior in a MAP process Short discussion on 1. the stability of a non-blind deconvolution process 2. noise resistant non-blind deconvolution and denoising
Stability Considering the simplest case: Wiener Filtering How about if And
Stability Thus where is the frequency domain representation of is the variance of the noise Observation: the noise in the blur image is magnified in the deconvolved image. And the Noise Magnification Factor (NMF) is solely determined by the filter
Some examples Dense kernels are less stable for deconvolution than sparse ones
Noise resistant deconvolution and denoising With Jiaya Jia, Singbing Kang and Zenlu Qin In CVPR 2010 See you in San Francisco! Blind and non-blind image deconvolution software is available online and will be updated soon! 40