Image Reconstruction by Linear Programming

— One way of image denoising is to project a noisy image to the subspace of admissible images derived, for instance by PCA. However, a major drawback of this method is that all pixels are updated by the projection, even when only a few pixels are corrupted by noise or occlusion. We propose a new method to identify the noisy pixels by 1-norm penalization and to update the identified pixels only. The identification and updating of noisy pixels are formulated as one linear program which can be efficiently solved. In particular, one can apply the ν-trick to directly specify the fraction of pixels to be reconstructed. Moreover, we extend the linear program to be able to exploit prior knowledge that occlusions often appear in contiguous blocks (e.g. sunglasses on faces). The basic idea is to penalize boundary points and interior points of the occluded area differently. We are also able to show the ν-property for this extended LP leading to a method which is easy to use. Experimental r...

• Type: Conference
• Year: 2003
• Where: NIPS
• Authors: Koji Tsuda, Gunnar Rätsch
• Keywords: Linear Program, NIPS 2003, NIPS 2007, Noisy Pixels, Pixels