Umar ÖZGÜNALP

Prof. Dr. Umar ÖZGÜNALP


Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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22 August 2019 in IEEE Transactions on Image Processing
Verified
Journal Article
Closed access
RFRui Fan
Rui Fan
UÖUmar ÖZGÜNALP
Umar ÖZGÜNALP
BHBrett Hosking
Brett Hosking
MLMing Liu
Ming Liu
IPIoannis Pitas
Ioannis Pitas
Pothole detection is one of the most important tasks for road maintenance. Computer vision approaches are generally based on either 2D road image analysis or 3D road surface modeling. However, these two categories are always used independently. Furthermore, the pothole detection accuracy is still far from satisfactory. Therefore, in this paper, we present a robust pothole detection algorithm that is both accurate and computationally efficient. A dense disparity map is first transformed to better distinguish between damaged and undamaged road areas. To achieve greater disparity transformation efficiency, golden section search and dynamic programming are utilized to estimate the transformation parameters. Otsu’s thresholding method is then used to extract potential undamaged road areas from the transformed disparity map. The disparities in the extracted areas are modeled by a quadratic surface using least squares fitting. To improve disparity map modeling robustness, the surface normal is also integrated into the surface modeling process. Furthermore, random sample consensus is utilized to reduce the effects caused by outliers. By comparing the difference between the actual and modeled disparity maps, the potholes can be detected accurately. Finally, the point clouds of the detected potholes are extracted from the reconstructed 3D road surface. The experimental results show that the successful detection accuracy of the proposed system is around 98.7% and the overall pixel-level accuracy is approximately 99.6%.

24 March 2021 in IEEE Transactions on Cybernetics
Verified
Journal Article
Closed access
RFRui Fan
Rui Fan
UÖUmar ÖZGÜNALP
Umar ÖZGÜNALP
YWYuan Wang
Yuan Wang
MLMing Liu
Ming Liu
IPIoannis Pitas
Ioannis Pitas
Potholes are one of the most common forms of road damage, which can severely affect driving comfort, road safety, and vehicle condition. Pothole detection is typically performed by either structural engineers or certified inspectors. However, this task is not only hazardous for the personnel but also extremely time consuming. This article presents an efficient pothole detection algorithm based on road disparity map estimation and segmentation. We first incorporate the stereo rig roll angle into shifting distance calculation to generalize perspective transformation. The road disparities are then efficiently estimated using semiglobal matching. A disparity map transformation algorithm is then performed to better distinguish the damaged road areas. Subsequently, we utilize simple linear iterative clustering to group the transformed disparities into a collection of superpixels. The potholes are finally detected by finding the superpixels, whose intensities are lower than an adaptively determined threshold. The proposed algorithm is implemented on an NVIDIA RTX 2080 Ti GPU in CUDA. The experimental results demonstrate that our proposed road pothole detection algorithm achieves state-of-the-art accuracy and efficiency.

26 January 2023 in Electronics
Verified
Journal Article
Open access
PDF file
AHAmna Mansur Hendr
Amna Mansur Hendr
UÖUmar ÖZGÜNALP
Umar ÖZGÜNALP
MEMeryem Erbilek
Meryem Erbilek
Autism spectrum disorder as a condition has posed significant early diagnosis challenges to the medical and health community for a long time. The early diagnosis of ASD is crucial for early intervention and adequate management of the condition. Several kinds of literature have shown that children with ASD have varying degrees of challenges in handwriting tasks; hence, this research has proposed the creation of a handwritten dataset of both ASD and non-ASD subjects for deep learning classification. The created dataset is based on a series of handwritten tasks given to subjects such as drawing and writing. The dataset was used to propose a deep learning automated ASD diagnosis method. Using the GoogleNet transfer learning algorithm, each handwritten task in the dataset is trained and classified for each subject. This is done because in real-life scenarios an ASD subject may not comply to performing and finishing all handwritten tasks. Using a training and testing ratio of 80:20, a total of 104 subjects’ handwritten tasks were used as input for training and classification, and it is shown that the proposed approach can correctly classify ASD with an accuracy of 90.48%, where sensitivity, specificity, and F1 score are calculated as 80%, 100%, and 100%, respectively. The results of our proposed method exhibit an impressive performance and indicate that the use of handwritten tasks has a significant potential for the early diagnosis of ASD.

27 January 2020 in Turkish Journal of Electrical Engineering and Computer Sciences
Verified
Journal Article
Closed access
UÖUmar ÖZGÜNALP
Umar ÖZGÜNALP

28 January 2020 in IEEE Transactions on Image Processing
Verified
Journal Article
Closed access
RFRui Fan
Rui Fan
UÖUmar ÖZGÜNALP
Umar ÖZGÜNALP
BHBrett Hosking
Brett Hosking
MLMing Liu
Ming Liu
IPIoannis Pitas
Ioannis Pitas
Unfortunately, we made two minor mistakes in the above paper. First of all, the first graph on row (c) in Fig. 11 was same as the third graph on row (c) in Fig. 11 . Secondly, “precision” and “recall” in Table III need to be switched. The correct figure and table have no influence on the discussion and conclusions in the above paper, and they are given here.

31 December 2020 in arXiv
Verified
Preprint
Open access
PDF file
RFRui Fan
Rui Fan
UÖUmar ÖZGÜNALP
Umar ÖZGÜNALP
YWYuan Wang
Yuan Wang
MLMing Liu
Ming Liu
IPIoannis Pitas
Ioannis Pitas
Potholes are one of the most common forms of road damage, which can severely affect driving comfort, road safety and vehicle condition. Pothole detection is typically performed by either structural engineers or certified inspectors. This task is, however, not only hazardous for the personnel but also extremely time-consuming. This paper presents an efficient pothole detection algorithm based on road disparity map estimation and segmentation. We first generalize the perspective transformation by incorporating the stereo rig roll angle. The road disparities are then estimated using semi-global matching. A disparity map transformation algorithm is then performed to better distinguish the damaged road areas. Finally, we utilize simple linear iterative clustering to group the transformed disparities into a collection of superpixels. The potholes are then detected by finding the superpixels, whose values are lower than an adaptively determined threshold. The proposed algorithm is implemented on an NVIDIA RTX 2080 Ti GPU in CUDA. The experiments demonstrate the accuracy and efficiency of our proposed road pothole detection algorithm, where an accuracy of 99.6% and an F-score of 89.4% are achieved.