We carry out deconvolution by transforming the data into a new general discrete Radon domain that can handle any assumed boundary conditions for the associated matrix inversion problem. For each associated component (projection), one can then apply deconvolution routines to smaller (and possibly better) conditioned matrix inversion problems than the matrix inversion problem for the entire image. We demonstrate this new scheme by adaptively deconvolving these components using a combination of regularized inversion and wavelet filtering techniques. This procedure allows us to provide image estimates based on a generalized ridgelet frame. We then devise methods for carrying out this scheme locally to provide estimates based on generalized multiscaled ridgelets which are then filtered and combined to form an estimate from a curvelet-like domain. The techniques presented here suggest a whole new paradigm for developing deconvolution algorithms that incorporate leading deconvolution schemes. Various experimental results show that our methods can perform significantly better than standard deconvolution techniques.
Introduction.A typical restoration problem can be modeled as the desired image convolved with some type of point spread function. The resulting degraded image is referred to as a blurred image, and the recovery of the original image from the blurred image is called deconvolution. It is well known that such a problem is ill-posed.In this work, we propose a new generalized discrete Radon transform (GDRT) that avoids interpolation and reduces a two-dimensional discrete deconvolution problem into a set of onedimensional discrete inverse problems. A preliminary version of this GDRT was given in [6] and has been extended here to deal with deconvolution problems that can be solved by a variety of inverse problem methods. Besides reducing the complexity for each inverse problem, splitting the image deconvolution problem into a set of smaller-sized matrix inversion problems has other advantages. The matrices for these smaller problems may be better conditioned, and the underlying signals to be estimated tend to be smoother than the corresponding segments extracted from the original image, yielding better estimates. There is also a natural noise filtering when inverting the GDRT. We illustrate these benefits with many examples and, whenever possible, provide a detailed analysis from a numerical linear algebra perspective.We illustrate the usefulness of this new transform method for deconvolution by examining wavelet-based regularization schemes on the associated one-dimensional problems. These