167 citations · 962 across the 54 of their papers we have counts for
26 papers · 1 filter
On the Contractivity of Plug-and-Play Operators
Chirayu D. Athalye, Kunal N. Chaudhury, Bhartendu Kumar
In plug-and-play (PnP) regularization, the proximal operator in algorithms such as ISTA and ADMM is replaced by a powerful denoiser. This formal substitution works surprisingly wel…
Least-squares registration of point sets over SE (d) using closed-form projections
Sk. Miraj Ahmed, Niladri Ranjan Das, Kunal Narayan Chaudhury
Consider the problem of registering multiple point sets in some -dimensional space using rotations and translations. Assume that there are sets with common points, and moreover…
Fast High-Dimensional Kernel Filtering
Pravin Nair, Kunal N. Chaudhury
The bilateral and nonlocal means filters are instances of kernel-based filters that are popularly used in image processing. It was recently shown that fast and accurate bilateral f…
Linearized ADMM and Fast Nonlocal Denoising for Efficient Plug-and-Play Restoration
Unni V. S., Sanjay Ghosh, Kunal N. Chaudhury
In plug-and-play image restoration, the regularization is performed using powerful denoisers such as nonlocal means (NLM) or BM3D. This is done within the framework of alternating…
Fast High-Dimensional Bilateral and Nonlocal Means Filtering
Pravin Nair, Kunal. N. Chaudhury
Existing fast algorithms for bilateral and nonlocal means filtering mostly work with grayscale images. They cannot easily be extended to high-dimensional data such as color and hyp…
Fast Adaptive Bilateral Filtering
Ruturaj G. Gavaskar, Kunal N. Chaudhury
In the classical bilateral filter, a fixed Gaussian range kernel is used along with a spatial kernel for edge-preserving smoothing. We consider a generalization of this filter, the…
Artifact reduction for separable non-local means
Sanjay Ghosh, Kunal N. Chaudhury
It was recently demonstrated [J. Electron. Imaging, 25(2), 2016] that one can perform fast non-local means (NLM) denoising of one-dimensional signals using a method called lifting.…
Pruned non-local means
Sanjay Ghosh, Amit K. Mandal, Kunal N. Chaudhury
In Non-Local Means (NLM), each pixel is denoised by performing a weighted averaging of its neighboring pixels, where the weights are computed using image patches. We demonstrate th…
Fast and High-Quality Bilateral Filtering Using Gauss-Chebyshev Approximation
Sanjay Ghosh, Kunal N. Chaudhury
The bilateral filter is an edge-preserving smoother that has diverse applications in image processing, computer vision, computer graphics, and computational photography. The filter…
Fast Bilateral Filtering of Vector-Valued Images
Sanjay Ghosh, Kunal N. Chaudhury
In this paper, we consider a natural extension of the edge-preserving bilateral filter for vector-valued images. The direct computation of this non-linear filter is slow in practic…
Fast and Provably Accurate Bilateral Filtering
Kunal N. Chaudhury, Swapnil D. Dabhade
The bilateral filter is a non-linear filter that uses a range filter along with a spatial filter to perform edge-preserving smoothing of images. A direct computation of the bilater…
On Fast Bilateral Filtering using Fourier Kernels
Sanjay Ghosh, Kunal N. Chaudhury
It was demonstrated in earlier work that, by approximating its range kernel using shiftable functions, the non-linear bilateral filter can be computed using a series of fast convol…
A Simple Yet Effective Improvement to the Bilateral Filter for Image Denoising
Kollipara Rithwik, Kunal Narayan Chaudhury
The bilateral filter has diverse applications in image processing, computer vision, and computational photography. In particular, this non-linear filter is quite effective in denoi…
Fast and Accurate Bilateral Filtering using Gauss-Polynomial Decomposition
Kunal N. Chaudhury
The bilateral filter is a versatile non-linear filter that has found diverse applications in image processing, computer vision, computer graphics, and computational photography. A…
Image Denoising using Optimally Weighted Bilateral Filters: A Sure and Fast Approach
Kunal N. Chaudhury, Kollipara Rithwik
The bilateral filter is known to be quite effective in denoising images corrupted with small dosages of additive Gaussian noise. The denoising performance of the filter, however, i…
A new ADMM algorithm for the Euclidean median and its application to robust patch regression
Kunal N. Chaudhury, K. R. Ramakrishnan
The Euclidean Median (EM) of a set of points in an Euclidean space is the point x minimizing the (weighted) sum of the Euclidean distances of x to the points in . While ther…
Fast Separable Non-Local Means
S. Ghosh, K. N. Chaudhury
We propose a simple and fast algorithm called PatchLift for computing distances between patches (contiguous block of samples) extracted from a given one-dimensional signal. PatchLi…
Global registration of multiple point clouds using semidefinite programming
Kunal N. Chaudhury, Yuehaw Khoo, Amit Singer
Consider points in and local coordinate systems that are related through unknown rigid transforms. For each point we are given (possibly noisy) measurements…
On the convergence of the IRLS algorithm in Non-Local Patch Regression
Kunal N. Chaudhury
Recently, it was demonstrated in [CS2012,CS2013] that the robustness of the classical Non-Local Means (NLM) algorithm [BCM2005] can be improved by incorporating $\ell^p (0 < p \leq…
Non-Local Patch Regression: Robust Image Denoising in Patch Space
Kunal N. Chaudhury, Amit Singer
It was recently demonstrated in [Chaudhury et al.,Non-Local Euclidean Medians,2012] that the denoising performance of Non-Local Means (NLM) can be improved at large noise levels by…
Non-Local Euclidean Medians
Kunal N. Chaudhury, Amit Singer
In this letter, we note that the denoising performance of Non-Local Means (NLM) at large noise levels can be improved by replacing the mean by the Euclidean median. We call this ne…
Acceleration of the shiftable O(1) algorithm for bilateral filtering and non-local means
Kunal N. Chaudhury
A direct implementation of the bilateral filter [1] requires O(σ_s^2) operations per pixel, where σ_s is the (effective) width of the spatial kernel. A fast implementation of the b…
Improvements on "Fast space-variant elliptical filtering using box splines"
Kunal N. Chaudhury, Sebanti Sanyal
It is well-known that box filters can be efficiently computed using pre-integrations and local finite-differences [Crow1984,Heckbert1986,Viola2001]. By generalizing this idea and b…
Constant-time filtering using shiftable kernels
Kunal Narayan Chaudhury
It was recently demonstrated in [5] that the non-linear bilateral filter [14] can be efficiently implemented using a constant-time or O(1) algorithm. At the heart of this algorithm…