Spelling suggestions: "subject:"image enhancement"" "subject:"lmage enhancement""
11 |
User aid-based evolutionary computation for optimal parameter setting of image enhancement and segmentationDarvish, Arman 01 December 2011 (has links)
Applications of imaging and image processing become a part of our daily life
and find their crucial way in real-world areas. Accordingly, the corresponding
techniques get more and more complicated.
Many tasks are recognizable for a image processing chain, such as, filtering, color
balancing, enhancement, segmentation, and post processing. Generally speaking,
all of the image processing techniques need a control parameter setting. The better
these parameters are set the better results can be achieved. Usually, these parameters
are real numbers so search space is really large and brute-force searching
is impossible or at least very time consuming. Therefore, the optimal setting of
the parameters is an essential requirement to obtain desirable results. Obviously,
we are faced with an optimization problem, which its complexity depends on the
number of the parameters to be optimized and correlation among them.
By reviewing the optimization methods, it can be understood that metaheuristic
algorithms are the best candidates for these kind of problems. Metaheuristic
algorithms are iterative approaches which can search very complex large spaces to
come up with an optimal or close to optimal solution(s). They are able to solve
black-box global optimization problems which are not solvable by classic mathematical
methods.
The first part of this thesis optimizes the control parameters for an eye-illusion,
image enhancement, and image thresholding tasks by using an interactive evolutionary
optimization approach. Eye illusion and image enhancement are subjective
human perception-based issues, so, there is no proposed analytical fitness function
for them. Their optimization is only possible through interactive methods. The second
part is about setting of active contour (snake) parameters. The performance
of active contours (snakes) is sensitive to its eight correlated control parameters
which makes the parameter setting problem complex to solve. In this work, wehave tried to set the parameters to their optimal values by using a sample segmented
image provided by an expert. As our case studies, we have used breast
ultrasound, prostate ultrasound, and lung X-ray medical images. The proposed
schemes are general enough to be investigated with other optimization methods
and also image processing tasks. The achieved experimental results are promising
for both directions, namely, interactive-based image processing and sample-based
medical image segmentation. / UOIT
|
12 |
GPU-Accelerated Real-Time Surveillance De-WeatheringPettersson, Niklas January 2013 (has links)
A fully automatic de-weathering system to increase the visibility/stability in surveillance applications during bad weather has been developed. Rain, snow and haze during daylight are handled in real-time performance with acceleration from CUDA implemented algorithms. Video from fixed cameras is processed on a PC with no need of special hardware except an NVidia GPU. The system does not use any background model and does not require any precalibration. Increase in contrast is obtained in all haze/rain/snow-cases while the system lags the maximum of one frame during rain or snow removal. De-hazing can be obtained for any distance to simplify tracking or other operating algorithms on a surveillance system.
|
13 |
Image enhancement for improving visibility and feature recognitionZubair, Juwairia 10 October 2008 (has links)
Researchers analyze images in areas such as geology, bat cardiovascular systems
and art studies to verify their observations. Some images are hard to study as their details
are not vivid; hence there is a need to enhance these images to facilitate their study while
preserving their contents. This study is aimed at assisting the researchers in the
Cardiovascular Systems Dynamic Laboratory at Texas A&M University by evaluating
the importance of Image Enhancement (IE) for improving visibility of features.
For this study the images were collected and manipulated using various IE
techniques and were shown to the novice researchers who were asked to perform three
different tasks. These tasks were representative of the research work conducted in the
lab. The techniques that were selected aimed at reducing the problems that are usually
associated with data obtained from microscopic feeds. A customized application was
developed to expedite and automate the study. The results indicated that the researchers
did not immmensely benefit from the improved visualization for easy tasks. However,
their performance improved for tasks that required more practice and skill. Our approach
contributes towards designing an effective training program for novice researchers in
the lab. Moreover, it is promising for similar research in different fields of study.
|
14 |
FUSION-BASED AND FLICKER-FREE DEFOGGINGGuo, Jing-Ming, Syue, Jin-Yu, Radzicki, Vincent, Lee, Hua 11 1900 (has links)
Degradation in visibility is often introduced to images captured in poor weather conditions, such as
fog or haze. In this paper, a fusion-based transmission estimation method is introduced to adaptively
combine two different transmission models. Specifically, the new fusion weighting scheme and the
atmospheric light computed from the Gaussian-based dark channel method improves the estimation
of the locations of the light sources. To reduce the flickering effect introduced during the process of
frame-based dehazing, a flicker-free module is formulated to alleviate the impacts. The system
assessments show this approach is capable of superior defogging and dehazing performance,
compared to the state-of-the-art methods, both quantitatively and qualitatively
|
15 |
The Design and Implementation of a Digital Magnetic Tape System and its Application in Radio-Isotope ScanningBlum, Leon Stephen January 1972 (has links)
This thesis is divided into two general sections. The first deals with the theory of digital magnetic recording and surveys the more common techniques used in digital magnetic tape recording. A new recording format is described which leads to a greater data rate at normal recording densities. The design and implementation of a recording system using this technique is described.
The second section outlines the design of a portable digital recording system compatible with the peripheral unit described in section 1. The application of this system to the acquisition of data from a radioisotope scanner used in nuclear medicine is described and some basic results obtained from the system are demonstrated. Fundamental work towards image enhancement is outlined. / Thesis / Master of Engineering (ME)
|
16 |
Visual Evaluation of 3D Image EnhancementAdolfsson, Karin January 2006 (has links)
<p>Technologies in image acquisition have developed and often provide image volumes in more than two dimensions. Computer tomography and magnet resonance imaging provide image volumes in three spatial dimensions. The image enhancement methods have developed as well and in this thesis work 3D image enhancement with filter networks is evaluated.</p><p>The aims of this work are; to find a method which makes the initial parameter settings in the 3D image enhancement processing easier, to compare 2D and 3D processed image volumes visualized with different visualization techniques and to give an illustration of the benefits with 3D image enhancement processing visualized using these techniques.</p><p>The results of this work are;</p><p>1. a parameter setting tool that makes the initial parameter setting much easier and</p><p>2. an evaluation of 3D image enhancement with filter networks that shows a significant enhanced image quality in 3D processed image volumes with a high noise level compared to the 2D processed volumes. These results are shown in slices, MIP and volume rendering. The differences are even more pronounced if the volume is presented in a different projection than the volume is 2D processed in.</p>
|
17 |
Visual Evaluation of 3D Image EnhancementAdolfsson, Karin January 2006 (has links)
Technologies in image acquisition have developed and often provide image volumes in more than two dimensions. Computer tomography and magnet resonance imaging provide image volumes in three spatial dimensions. The image enhancement methods have developed as well and in this thesis work 3D image enhancement with filter networks is evaluated. The aims of this work are; to find a method which makes the initial parameter settings in the 3D image enhancement processing easier, to compare 2D and 3D processed image volumes visualized with different visualization techniques and to give an illustration of the benefits with 3D image enhancement processing visualized using these techniques. The results of this work are; 1. a parameter setting tool that makes the initial parameter setting much easier and 2. an evaluation of 3D image enhancement with filter networks that shows a significant enhanced image quality in 3D processed image volumes with a high noise level compared to the 2D processed volumes. These results are shown in slices, MIP and volume rendering. The differences are even more pronounced if the volume is presented in a different projection than the volume is 2D processed in.
|
18 |
Radiation dose and image quality in diagnostic radiology : optimization of the dose - image quality relationship with clinical experience from scoliosis radiography, coronary intervention and a flat-panel digital detector /Geijer, Håkan, January 2001 (has links)
Diss. (sammanfattning) Linköping : Univ., 2001. / Härtill 5 uppsatser.
|
19 |
A No-reference Image Enhancement Quality Metric and Fusion TechniqueHeadlee, Jonathan Michael 27 May 2015 (has links)
No description available.
|
20 |
An Accelerated General Purpose No-Reference Image Quality Assessment Metric and an Image Fusion TechniqueHettiarachchi, Don Lahiru Nirmal Manikka 09 September 2016 (has links)
No description available.
|
Page generated in 0.092 seconds