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- Electrical Engineering and Computer Science Faculty Publications (4)
- Dissertations & Theses (Open Access) (1)
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Articles 1 - 8 of 8
Full-Text Articles in Engineering
Scale-Invariant Histogram Of Oriented Gradients: Novel Approach For Pedestriandetection In Multiresolution Image Dataset, Sweta Panigrahi, Surya Narayana Raju Undi
Scale-Invariant Histogram Of Oriented Gradients: Novel Approach For Pedestriandetection In Multiresolution Image Dataset, Sweta Panigrahi, Surya Narayana Raju Undi
Turkish Journal of Electrical Engineering and Computer Sciences
This paper proposes a scale-invariant histogram of oriented gradients (SI-HOG) for pedestrian detection. Most of the algorithms for pedestrian detection use the HOG as the basic feature and combine other features with the HOG to form the feature set, which is usually applied with a support vector machine (SVM). Hence, the HOG feature is the most efficient and fundamental feature for pedestrian detection. However, the HOG feature produces feature vectors of different lengths for different image resolutions; thus, the feature vectors are incomparable for the SVM. The proposed method forms a scale-space pyramid wherein the histogram bin is calculated. Thus, …
New Tools For Monitoring Gamma Camera Uniformity, Brad K. Lofton
New Tools For Monitoring Gamma Camera Uniformity, Brad K. Lofton
Dissertations & Theses (Open Access)
Detector uniformity is a fundamental performance characteristic of all modern gamma camera systems, and ensuring a stable, uniform detector response is critical for maintaining clinical images that are free of artifact. For these reasons, the assessment of detector uniformity is one of the most common activities associated with a successful clinical quality assurance program in gamma camera imaging. The evaluation of this parameter, however, is often unclear because it is highly dependent upon acquisition conditions, reviewer expertise, and the application of somewhat arbitrary limits that do not characterize the spatial location of the non-uniformities. Furthermore, as the goal of any …
A Wavelet-Based Multiresolution Pid Controller, Shahid Parvez, Zhiqiang Gao
A Wavelet-Based Multiresolution Pid Controller, Shahid Parvez, Zhiqiang Gao
Electrical and Computer Engineering Faculty Publications
A novel controller based on multiresolution decomposition using wavelets is presented. The controller is similar to a proportional-integral-derivative (PID) controller in principle and application. The output from a motion control system represents the cumulative effect of uncertainties such as measurement noise, frictional variation, and external torque disturbances, which manifest at different scales. The wavelet is used to decompose the error signal into signals at different scales. These signals are then used to compensate for the uncertainties in the plant. This approach provides greater expanse over the degree of control applied to the system. Through hardware and simulation results on motion …
Semi-Automatic Road Extraction From Aerial Images, Somkait Udomhunsakul, Samuel Peter Kozaitis, Uthai Thai Sritheeravirojana
Semi-Automatic Road Extraction From Aerial Images, Somkait Udomhunsakul, Samuel Peter Kozaitis, Uthai Thai Sritheeravirojana
Electrical Engineering and Computer Science Faculty Publications
In this work, we proposed a method to detect roads in aerial imagery. In our approach, we applied the wavelet transform in a multiresolution sense by forming the products of wavelet coefficients at the different scales to locate and identify roads. After detecting possible road pixels, we used a graph searching algorithm to identify roads. We found that our approach leads to an effective method to form the basis of a road extraction approach.
Line Detection Using Wavelet Filters, Somkait Udomhunsakul, Samuel Peter Kozaitis, Uthai Thai Sritheeravirojana, A. Khempila
Line Detection Using Wavelet Filters, Somkait Udomhunsakul, Samuel Peter Kozaitis, Uthai Thai Sritheeravirojana, A. Khempila
Electrical Engineering and Computer Science Faculty Publications
We proposed a new line detection method in noisy images using Mexican hat wavelet filters. In our approach, we applied the wavelet transform in a multiresolution sense by forming the products of wavelet coefficients at the different scales to locate and identify lines at different scales. In addition, we also considered shifting line locations through multiple scales for robust line detection in the presence of noise. We found that our approach leads to an effective method to form the basis of a line detection approach.
Linear Feature Detection Using Multiresolution Wavelet Filters, Samuel Peter Kozaitis, Somkait Udomhunsakul, Rufus H. Cofer, A. Agarawal, Shuwu Song
Linear Feature Detection Using Multiresolution Wavelet Filters, Samuel Peter Kozaitis, Somkait Udomhunsakul, Rufus H. Cofer, A. Agarawal, Shuwu Song
Electrical Engineering and Computer Science Faculty Publications
We detected roads in aerial imagery based on multiresolution linear feature detection. Our method used the products of wavelet coefficients at several scales to identify and locate linear features. After detecting possible road pixels, we used a shortest-path algorithm to identify roads. The multiresolution approach effectively increased the size of the region we examined when looking for possible road pixels and reduced the effect of noise. We found that our approach leads to an effective method for detecting roads in aerial imagery.
Improved Wavelet-Based Multiresolution Edge Detection In Noisy Images, Yunwoo Lee, Samuel Peter Kozaitis
Improved Wavelet-Based Multiresolution Edge Detection In Noisy Images, Yunwoo Lee, Samuel Peter Kozaitis
Electrical Engineering and Computer Science Faculty Publications
We used the multiresolution property of the discrete wavelet transform to detect edges in noisy images. In our approach, we used wavelets corresponding to 1 and 2 derivatives to generate noisy wavelet coefficients. Then, we compared the wavelet COeffiCientS as a function of scale to reduce the effects of noise. In addition, our approach considered the change in edge position as a function of scale. We analyzed l..D experimental results and compar1 2..D results ofnoisy images to a more common edge detection method. Our results lead to improved edge detection resutts in noisy images.
Multiresolution Detection Of Spiculated Lesions In Digital Mammograms, Sheng Liu, Charles F. Babbs, Edward Delp
Multiresolution Detection Of Spiculated Lesions In Digital Mammograms, Sheng Liu, Charles F. Babbs, Edward Delp
Weldon School of Biomedical Engineering Faculty Publications
In this paper we present a novel multiresolution scheme for the detection of spiculated lesions in digital mammograms. First, a multiresolution representation of the original mammogram is obtained using a linear phase nonseparable 2-D wavelet transform. A set of features is then extracted at each resolution in the wavelet pyramid for every pixel. This approach addresses the difficulty of predetermining the neighborhood size for feature extraction to characterize objects that may appear in different sizes. Detection is performed from the coarsest resolution to the finest resolution using a binary tree classifier. This top-down approach requires less computation by starting with …