36 research outputs found
Single Frame Image super Resolution using Learned Directionlets
In this paper, a new directionally adaptive, learning based, single image
super resolution method using multiple direction wavelet transform, called
Directionlets is presented. This method uses directionlets to effectively
capture directional features and to extract edge information along different
directions of a set of available high resolution images .This information is
used as the training set for super resolving a low resolution input image and
the Directionlet coefficients at finer scales of its high-resolution image are
learned locally from this training set and the inverse Directionlet transform
recovers the super-resolved high resolution image. The simulation results
showed that the proposed approach outperforms standard interpolation techniques
like Cubic spline interpolation as well as standard Wavelet-based learning,
both visually and in terms of the mean squared error (mse) values. This method
gives good result with aliased images also.Comment: 14 pages,6 figure
A New Gridding Technique for High Density Microarray Images Using Intensity Projection Profile of Best Sub Image
As the technologies for the fabrication of high quality microarray advances rapidly, quantification of microarray data becomes a major task. Gridding is the first step in the analysis of microarray images for locating the subarrays and individual spots within each subarray. For accurate gridding of high-density microarray images, in the presence of contamination and background noise, precise calculation of parameters is essential. This paper presents an accurate fully automatic gridding method for locating suarrays and individual spots using the intensity projection profile of the most suitable subimage. The method is capable of processing the image without any user intervention and does not demand any input parameters as many other commercial and academic packages. According to results obtained, the accuracy of our algorithm is between 95-100% for microarray images with coefficient of variation less than two. Â Experimental results show that the method is capable of gridding microarray images with irregular spots, varying surface intensity distribution and with more than 50% contamination. Keywords: microarray, gridding, image processing, gridding accurac
Discrete wavelet transform de-noising in eukaryotic gene splicing
<p>Abstract</p> <p>Background</p> <p>This paper compares the most common digital signal processing methods of exon prediction in eukaryotes, and also proposes a technique for noise suppression in exon prediction. The specimen used here which has relevance in medical research, has been taken from the public genomic database - GenBank.</p> <p>Methods</p> <p>Here exon prediction has been done using the digital signal processing methods viz. binary method, EIIP (electron-ion interaction psuedopotential) method and filter methods. Under filter method two filter designs, and two approaches using these two designs have been tried. The discrete wavelet transform has been used for de-noising of the exon plots.</p> <p>Results</p> <p>Results of exon prediction based on the methods mentioned above, which give values closest to the ones found in the NCBI database are given here. The exon plot de-noised using discrete wavelet transform is also given.</p> <p>Conclusion</p> <p>Alterations to the proven methods as done by the authors, improves performance of exon prediction algorithms. Also it has been proven that the discrete wavelet transform is an effective tool for de-noising which can be used with exon prediction algorithms.</p
Fast Fractal Coding Method for the Detection of Microcalcification in Mammograms
The presence of microcalcifications in mammograms can be considered as an early indication of breast cancer. A fastfractal block coding method to model the mammograms fordetecting the presence of microcalcifications is presented in this paper. The conventional fractal image coding method takes enormous amount of time during the fractal block encoding.procedure. In the proposed method, the image is divided intoshade and non shade blocks based on the dynamic range, andonly non shade blocks are encoded using the fractal encodingtechnique. Since the number of image blocks is considerablyreduced in the matching domain search pool, a saving of97.996% of the encoding time is obtained as compared to theconventional fractal coding method, for modeling mammograms.The above developed mammograms are used for detectingmicrocalcifications and a diagnostic efficiency of 85.7% isobtained for the 28 mammograms used.Cochin University of Science and TechnologyIEEE-International Conference on Signal processing, Communications and Networking
Madras Institute of Technology, Anna University Chennai India, Jan 4-6, 2008. Pp368-37
Spatially Adaptive Image Denoising Techniques Using Directionlets
The aim of the thesis was to design and develop
spatially adaptive denoising techniques with edge and feature preservation, for
images corrupted with additive white Gaussian noise and SAR images affected
with speckle noise. Image denoising is a well researched topic. It has found multifaceted applications
in our day to day life. Image denoising based on multi resolution analysis using
wavelet transform has received considerable attention in recent years.
The directionlet based denoising schemes presented in this thesis are effective in
preserving the image specific features like edges and contours in denoising. Scope
of this research is still open in areas like further optimization in terms of speed and
extension of the techniques to other related areas like colour and video image
denoising. Such studies would further augment the practical use of these
techniques.Cochin University Of Science & Technolog
Video Object Tracking And Analysis For Computer Assisted Surgery
Pedicle screw insertion technique has made revolution in the surgical treatment of spinal fractures and spinal disorders. Although X- ray fluoroscopy based navigation is popular, there is risk of prolonged exposure to X- ray radiation. Systems that have lower radiation risk are generally quite expensive. The position and orientation of the drill is clinically very important in pedicle screw fixation. In this paper, the position and orientation of the marker on the drill is determined using pattern recognition based methods, using geometric features, obtained from the input video sequence taken from CCD camera. A search is then performed on the video frames after preprocessing, to obtain the exact position and orientation of the drill. An animated graphics, showing the instantaneous position and orientation of the drill is then overlaid on the processed video for real time drill control and navigationCochin University of Science & Technolog
A New Fast Fractal Modeling Approach for the Detection of Microcalcifications in Mammograms
In this paper, a novel fast method for modeling mammograms
by deterministic fractal coding approach to detect
the presence of microcalcifications, which are early
signs of breast cancer, is presented. The modeled
mammogram obtained using fractal encoding method is
visually similar to the original image containing microcalcifications,
and therefore, when it is taken out from
the original mammogram, the presence of microcalcifications
can be enhanced. The limitation of fractal image
modeling is the tremendous time required for encoding.
In the present work, instead of searching for a matching
domain in the entire domain pool of the image, three
methods based on mean and variance, dynamic range of
the image blocks, and mass center features are used.
This reduced the encoding time by a factor of 3, 89, and
13, respectively, in the three methods with respect to
the conventional fractal image coding method with quad
tree partitioning. The mammograms obtained from The
Mammographic Image Analysis Society database
(ground truth available) gave a total detection score of
87.6%, 87.6%, 90.5%, and 87.6%, for the conventional
and the proposed three methods, respectively.Cochin University of Science & TechnologyJournal of Digital Imaging, Vol 23, No 5 (October), 2010: pp 538-54
A New Gridding Technique for High Density Microarray Images Using Intensity Projection Profile of Best Sub Image
As the technologies for the fabrication of high quality microarray advances rapidly, quantification of
microarray data becomes a major task. Gridding is the first step in the analysis of microarray images for
locating the subarrays and individual spots within each subarray. For accurate gridding of high-density
microarray images, in the presence of contamination and background noise, precise calculation of
parameters is essential. This paper presents an accurate fully automatic gridding method for locating
suarrays and individual spots using the intensity projection profile of the most suitable subimage. The
method is capable of processing the image without any user intervention and does not demand any input
parameters as many other commercial and academic packages. According to results obtained, the accuracy
of our algorithm is between 95-100% for microarray images with coefficient of variation less than two.
Experimental results show that the method is capable of gridding microarray images with irregular spots,
varying surface intensity distribution and with more than 50% contaminationCochin University of Science and TechnologyComputer Engineering and Intelligent Systems,Vol.4, No.1, 201
Multifinger Feature Level Fusion Based Fingerprint Identification
Fingerprint based authentication systems are one of the cost-effective biometric authentication techniques employed for personal identification. As the data base population increases, fast identification/recognition algorithms are required with high accuracy. Accuracy can be increased using multimodal evidences collected by multiple biometric traits. In this work, consecutive fingerprint images are taken, global singularities are located using directional field strength and their local orientation vector is formulated with respect to the base line of the finger. Feature level fusion is carried out and a 32 element feature template is obtained. A matching score is formulated for the identification and 100% accuracy was obtained for a database of 300 persons. The polygonal feature vector helps to reduce the size of the feature database from the present 70-100 minutiae features to just 32 features and also a lower matching threshold can be fixed compared to single finger based identificationCochin University of Science and Technology(IJACSA) International Journal of Advanced Computer Science and Applications,
Vol. 3, No. 11, 201