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GPU computing with orientation maps for extracting local invariant features

N Ichimura
2010 2010 IEEE Computer Society Conference on Computer Vision and Pattern Recognition - Workshops  
By using multiresolutional orientation maps and applying Gaussian filters to them, we can obtain voting values for the histograms for all the pixels in a scale space pyramid.  ...  First, it improves the efficiency of parallel computing by reducing the number of memory access conflicts in the overlaps among local regions, and secondly it utilizes a fast implementation of Gaussian  ...  Gaussian filters, gradient filters and down sampling are combined to obtain multiresolutional edges. Examples of multiresolutional edge images are shown in Fig.3 .  ... 
doi:10.1109/cvprw.2010.5543742 dblp:conf/cvpr/Ichimura10 fatcat:ocwvuvi36zh4piaxd2zqsc3hvm

Contour Detection by Multiresolution Surround Inhibition

Giuseppe Papari, Patrizio Campisi, Nicolai Petkov, Alessandro Neri
2006 2006 International Conference on Image Processing  
To overcome this problem, we propose a multiresolution contour detector motivated by biological principles. At each scale, texture is suppressed by using a bipolar surround inhibition process.  ...  Often, the latter are stronger than the former, thus standard edge detectors fail in isolating object contours from texture.  ...  Our goal is to isolate objects in a scene; therefore, some further process is needed with respect to general purpose edge detectors.  ... 
doi:10.1109/icip.2006.312500 dblp:conf/icip/PapariCPN06 fatcat:to3iseytavf5db32gqqdxlewiy

Enhancement of document images using multiresolution and fuzzy logic techniques

F. Sattar, D.B.H. Tay
1999 IEEE Signal Processing Letters  
This letter presents a method for enhancing document images based on the multiresolution decomposition and fuzzy logic approach.  ...  The document image to be enhanced is obtained from a scanner and is a blurred binary image that is corrupted by additive noise.  ...  For a pixel point the edge values ( ) are calculated as where This method is less sensitive to the increment of noise due to the averaging of all of the gray levels that are weighted by the edge values  ... 
doi:10.1109/97.789601 fatcat:2opq5rsrdrgprmkdfmg342lsfq

A Biologically Motivated Multiresolution Approach to Contour Detection

Giuseppe Papari, Patrizio Campisi, Nicolai Petkov, Alessandro Neri
2007 EURASIP Journal on Advances in Signal Processing  
In this paper, we propose a biologically motivated multiresolution contour detection method using Bayesian denoising and a surround inhibition technique.  ...  Standard edge detectors react to all local luminance changes, irrespective of whether they are due to the contours of the objects represented in a scene or due to natural textures like grass, foliage,  ...  To this aim, let us describe the marginal distribution of ∇ σ I(x, y) with a rather general model constituted by a Gaussian mixture, that is, a weighted sum of Gaussian distributions: p ∇σ I ∇ σ I(x, y  ... 
doi:10.1155/2007/71828 fatcat:uilqlrevtzeg7amznhx2xykvwy

Application of edge detection technique for surface roughness estimation of Ti-6Al-4V turned surfaces

J. S. Vishwanatha, P. Srinivasa Pai
In this research work, a heuristic method based on biologically motivated Particle Swarm Optimization (PSO) has been proposed for edge detection using multiresolution decomposition, to enhance the quality  ...  The performance of DTCWT with PSO method is examined for turned surface images and compared with conventional edge detectors like Canny, and Sobel methods along with Discrete Wavelet Transform (DWT) with  ...  A comparison with DWT and DTCWT without edge detection, establishes the significance of use of edge detectors in improving the quality of turned images.  ... 
doi:10.21062/mft.2021.029 fatcat:23lmvp7mozaszc6kiruydfk26y

Wavelet-based system for recognition and labeling of polyhedral junctions

Terrance Huntsberger
1998 Optical Engineering: The Journal of SPIE  
A wavelet-based system for polyhedral junction recognition that combines the wavelet-derived edges and line elements at multiple levels of resolution to produce a labeled image is introduced.  ...  The multiresolution feature extraction algorithm consists of two main parts: the multiresolution edge detector and the multiresolution edgel aggregation algorithm.  ...  The first edge-detection method using a Gaussian-shaped low-pass filter is described as follows: 6 1.  ... 
doi:10.1117/1.601843 fatcat:owanjm7luja5nbbkh62u7rr6gq

Extracting multi-size local descriptors by GPU computing

Naoyuki Ichimura
2011 2011 IEEE International Conference on Multimedia and Expo  
Using orientation maps, we can calculate the descriptors by a table look-up manner.  ...  This paper presents fast computational techniques for extracting local descriptors from multiple local regions associated with an image feature such as a feature point.  ...  Gaussian filters, gradient filters and down sampling are combined to obtain multiresolutional edges. Multiresolutional edges can also be used for local region detection [8, 20] .  ... 
doi:10.1109/icme.2011.6012157 dblp:conf/icmcs/Ichimura11 fatcat:3hs523v2yrge5aby2tdzzv3jiy

Contour Detection By Surround Inhibition In The Circular Harmonic Functions Domain

P. Campisi, Giuseppe Papari, Nicolai Petkov
2006 Zenodo  
MULTIRESOLUTION CONTOUR DETECTOR As well known from multiresolution analysis [11] , the outputs of coarse scale edge detectors do not contain much texture (Fig. 2a) , but contours are smoothed and shifted  ...  Figure 7 -(a) Input image "Elephant" and contours detected with: (b) the proposed approach, (c) the Canny edge detector, (d) the multiscale edge detector CARTOON without surround inhibition [6] , (e)  ... 
doi:10.5281/zenodo.52812 fatcat:czfpgba5urbc7jb25p6ajipe2e

Hybrid Speckle Noise Reduction Method for Abdominal Circumference Segmentation of Fetal Ultrasound Images

Fajar Astuti Hermawati, Handayani Tjandrasa, Nanik Suciati
2018 International Journal of Electrical and Computer Engineering (IJECE)  
In this paper, we proposed a hybrid ultrasound image denoising framework which was a combination of spatial-based filtering method and multiresolution based method.  ...  Fetal biometric size such as abdominal circumference (AC) is used to predict fetal weight or gestational age in ultrasound images.  ...  At the first step, the Canny edge detector is applied to get the boundaries in the binary image and afterwards the result is processed by the Gaussian smoothing filter.  ... 
doi:10.11591/ijece.v8i3.pp1747-1757 fatcat:pnfafqvegbdxzgxn3n3s37fwsi

Multiresolution iterative reconstruction in high-resolution extremity cone-beam CT

Qian Cao, Wojciech Zbijewski, Alejandro Sisniega, John Yorkston, Jeffrey H Siewerdsen, J Webster Stayman
2016 Physics in Medicine and Biology  
To reduce the computational burden of high resolution MBIR, we propose a multiresolution Penalized-Weighted Least Squares (PWLS) algorithm, where the volume is parameterized as a union of fine and coarse  ...  voxel grids as well as selective binning of detector pixels.  ...  The authors thank Ali Uneri (Department of Computer Science, Johns Hopkins University) for valuable discussion regarding computer implementation of multiresolution projectors.  ... 
doi:10.1088/0031-9155/61/20/7263 pmid:27694701 pmcid:PMC5061055 fatcat:dqyoby4gmzakbjk5inh46eteiq

Locally adaptive image denoising by a statistical multiresolution criterion [article]

Thomas Hotz, Philipp Marnitz, Rahel Stichtenoth, Laurie Davies, Zakhar Kabluchko, Axel Munk
2010 arXiv   pre-print
We demonstrate how one can choose the smoothing parameter in image denoising by a statistical multiresolution criterion, both globally and locally.  ...  As expected, the smoothing parameter serves as an edge detector in this framework. Numerical examples illustrate the usefulness of our approach. We also present an application in confocal microscopy.  ...  This behaviour of the local diffusivity as an edge-detector is very much apparent in Figure 7(a) .  ... 
arXiv:1001.5447v1 fatcat:tndpcaay2zc4dlr63krairtj3q

Multiscale MAP filtering of SAR images

S. Foucher, G.B. Benie, J.-M. Boucher
2001 IEEE Transactions on Image Processing  
In this study, we propose to filter this noise with a multiresolution analysis of the image.  ...  The wavelet coefficient of the reflectivity is estimated with a Bayesian model, maximizing the a posteriori probability density function.  ...  Improvements have been proposed, using more efficient edge detectors such as the Touzi's detector [4] , [5] .  ... 
doi:10.1109/83.892442 pmid:18249596 fatcat:sjqwejmh4zh7dat7suzvjcb2oq

Image enhancement based on a nonlinear multiscale method

F. Sattar, L. Floreby, G. Salomonsson, B. Lovstrom
1997 IEEE Transactions on Image Processing  
An image enhancement method that reduces speckle noise and preserves edges is introduced.  ...  The method is based on a new nonlinear multiscale reconstruction scheme that is obtained by successively combining each coarser scale image with the corresponding modified interscale image.  ...  A window of size 3 2 3 pixels was used with the RoA edge detector.  ... 
doi:10.1109/83.585239 pmid:18282982 fatcat:ghxoukiuqzgpdlt7aawmhmectm

Image Fusion Algorithm Using the Multiresolution Directional-Oriented Hermite Transform [chapter]

Sonia Cruz-Techica, Boris Escalante-Ramirez
2011 Lecture Notes in Computer Science  
The Hermite transform is introduced as an image representation model for multiresolution image fusion with noise reduction.  ...  Image fusion is achieved by combining the steered Hermite coefficients of the source images, then the coefficients are combined with a decision rule based on the linear algebra through a measurement of  ...  This angle can be approximated as θ = L 01 /L 10 , where L 01 and L 10 are a good estimated to optimal edge detectors in the horizontal and vertical directions respectively ( Fig. 1 shows the HT and  ... 
doi:10.1007/978-3-642-21587-2_22 fatcat:ali254fb7baqllwsmdiw3tibwq

Edge and line oriented contour detection: State of the art

Giuseppe Papari, Nicolai Petkov
2011 Image and Vision Computing  
By edge and line oriented we mean methods that do not rely on segmentation. Distinction is made between edges and contours. Contour detectors are divided in local and global operators.  ...  Important aspects are covered, such as preprocessing aimed to suppress texture and noise, multiresolution techniques, connections between computational models and properties of the human visual system,  ...  From left to right: input image; outputs of the Canny edge detector for σ = 1, which exhibits multiple responses on blurred edges, and for σ = 4, which smooths sharp edges; output of the multiresolution  ... 
doi:10.1016/j.imavis.2010.08.009 fatcat:2c4jb2mybjgnvaejjzn77qwz6y
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