The document describes a 3D laser profiling system called the LCMS that can automatically measure road surface conditions like cracks, ruts, texture, and raveling. It does this using two high-resolution 3D laser profilers mounted on a vehicle that collect transverse road profiles up to 100km/h. Algorithms then analyze the 3D and intensity data to detect and classify various surface features. The LCMS was tested on over 10,000km of road network and showed over 95% accuracy in crack detection when compared to manual results. It provides reliable, continuous assessment of pavement conditions for maintenance planning.
The document describes a lane detection algorithm that uses color thresholding, Canny edge detection, and perspective transforms to extract lane markings from road images. It then uses histograms to determine starting points for lane lines and sliding windows to detect pixels belonging to each lane line from the starting points upwards. Finally, it fits polynomials to detected pixels to determine the lane boundaries. The algorithm is tested on 1000 frames from a road trip video with a runtime of 1.24 seconds per frame and good accuracy at detecting lanes under varying conditions without camera calibration.
We performed the project on Lane detection by using canny edge and Hough transform at the University of Windsor. In this presentation, all the code used in Python are perfectly presented for reference.
International Journal of Computational Engineering Research (IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
LocalizationandMappingforAutonomousNavigationin OutdoorTerrains: A StereoVisi...Minh Quan Nguyen
The document discusses localization and mapping techniques for autonomous navigation using stereo vision. It describes using efficient stereo algorithms to build local maps, visual odometry for precise registration of robot motion and maps, and integrating local maps into a globally consistent map. The approach is tested in outdoor environments, where it is able to build accurate maps in real-time and outperform other teams in validation tests.
camera-based Lane detection by deep learningYu Huang
lane detection, deep learning, autonomous driving, CNN, RNN, LSTM, GRU, lane localization, lane fitting, ego lane, end-to-end, vanishing point, segmentation, FCN, regression, classification
TRAFFIC-SIGN RECOGNITION FOR AN INTELLIGENT VEHICLE/DRIVER ASSISTANT SYSTEM U...cseij
The document describes a traffic sign recognition system using HOG features and a k-NN classifier. The system first detects signs using RGB color thresholding and shape analysis. It then extracts HOG features from the segmented images. Finally, it classifies the signs using a k-NN classifier. The system was tested on a database of 200 traffic sign images under varying lighting conditions. It achieved a classification accuracy of 63%. The proposed approach provides robust traffic sign recognition while being invariant to scale, rotation, and illumination changes.
EVALUATION OF THE VISUAL ODOMETRY METHODS FOR SEMI-DENSE REAL-TIMEacijjournal
This document summarizes the evaluation of visual odometry methods for semi-dense real-time reconstruction. It discusses two popular visual odometry approaches, LSD-SLAM and ORB-SLAM2, and evaluates their performance on three datasets. It then proposes a new approach that combines feature-based and feature-less methods for real-time odometry with a stereo camera, matching images semi-densely and reconstructing 3D environments directly on pixels with gradients.
The document describes a lane detection algorithm that uses color thresholding, Canny edge detection, and perspective transforms to extract lane markings from road images. It then uses histograms to determine starting points for lane lines and sliding windows to detect pixels belonging to each lane line from the starting points upwards. Finally, it fits polynomials to detected pixels to determine the lane boundaries. The algorithm is tested on 1000 frames from a road trip video with a runtime of 1.24 seconds per frame and good accuracy at detecting lanes under varying conditions without camera calibration.
We performed the project on Lane detection by using canny edge and Hough transform at the University of Windsor. In this presentation, all the code used in Python are perfectly presented for reference.
International Journal of Computational Engineering Research (IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
LocalizationandMappingforAutonomousNavigationin OutdoorTerrains: A StereoVisi...Minh Quan Nguyen
The document discusses localization and mapping techniques for autonomous navigation using stereo vision. It describes using efficient stereo algorithms to build local maps, visual odometry for precise registration of robot motion and maps, and integrating local maps into a globally consistent map. The approach is tested in outdoor environments, where it is able to build accurate maps in real-time and outperform other teams in validation tests.
camera-based Lane detection by deep learningYu Huang
lane detection, deep learning, autonomous driving, CNN, RNN, LSTM, GRU, lane localization, lane fitting, ego lane, end-to-end, vanishing point, segmentation, FCN, regression, classification
TRAFFIC-SIGN RECOGNITION FOR AN INTELLIGENT VEHICLE/DRIVER ASSISTANT SYSTEM U...cseij
The document describes a traffic sign recognition system using HOG features and a k-NN classifier. The system first detects signs using RGB color thresholding and shape analysis. It then extracts HOG features from the segmented images. Finally, it classifies the signs using a k-NN classifier. The system was tested on a database of 200 traffic sign images under varying lighting conditions. It achieved a classification accuracy of 63%. The proposed approach provides robust traffic sign recognition while being invariant to scale, rotation, and illumination changes.
EVALUATION OF THE VISUAL ODOMETRY METHODS FOR SEMI-DENSE REAL-TIMEacijjournal
This document summarizes the evaluation of visual odometry methods for semi-dense real-time reconstruction. It discusses two popular visual odometry approaches, LSD-SLAM and ORB-SLAM2, and evaluates their performance on three datasets. It then proposes a new approach that combines feature-based and feature-less methods for real-time odometry with a stereo camera, matching images semi-densely and reconstructing 3D environments directly on pixels with gradients.
Image Processing Applied To Traffic Queue Detection Algorithmguest673189
This document describes an image processing algorithm for detecting traffic queues using digital video from road cameras. The algorithm has two main operations: 1) motion detection using frame differencing to identify vehicle movement, and 2) vehicle detection using edge detection on image profiles to identify individual vehicles. The algorithm was tested on images captured from cameras at an intersection in College Station, Texas. Key results included accurately measuring queue length, occurrence period, and growth slope to analyze backup traffic forming at red lights.
A Much Advanced and Efficient Lane Detection Algorithm for Intelligent Highwa...cscpconf
This paper presents a much advanced and efficient lane detection algorithm. The algorithm is based on (ROI) Region of Interest segmentation. In this algorithm images are pre-processed by top-hat transform for de-noising and enhancing contrast. ROI of a test image is then extracted. For detecting lines in the ROI, Hough transform is used. Estimation of the distance between Hough origin and lane-line midpoint is made. Lane departure decision is made based on the difference between these distances. As for the simulation part we have used Matlab software.Experiments show that the proposed algorithm can detect the lane markings accurately and quickly.
A Study on Single Camera Based ANPR System for Improvement of Vehicle Number ...journal ijrtem
This document summarizes a study on a single camera-based automatic number plate recognition (ANPR) system to recognize vehicle license plates on multi-lane roads. It proposes a character extraction algorithm using connected vertical and horizontal edge segments to improve recognition rates. The algorithm detects character edge patterns, extracts components by cumulatively labeling edges, and enhances images through contrast adaptive binarization. An ANPR system was installed on a 3-lane test road and achieved a detection rate of 84.6%, though some errors occurred with specific vehicle models or character differences. Further research is needed to handle low-visibility conditions and improve accuracy.
A Study on Single Camera Based ANPR System for Improvement of Vehicle Number ...IJRTEMJOURNAL
In this paper, we introduce the single camera-based number recognition system used for this
system recognizes vehicle number plates on one lane by using a single camera. Intelligent transport system (ITS)
has been constructed because there is a limit in solving traffic problems in a physical manner such as construction
of roads and subways. The single camera-based number recognition system used for this system recognizes vehicle
number plates on one lane by using a single camera. Due to the increased cost of the installation and maintenance
thereof, there is a growing need for a multi-lane-based number recognition system. When the single camera-based
number recognition system is used for multi-lane recognition, the recognition rate is lowered due to a difference in
vehicle image size among lanes and a low-resolution problem. Therefore, in this study, we applied a character
extraction algorithm using connected vertical and horizontal edge segments-based labeling to improve multi-lane
vehicle number recognition rate and thereby to allow application of the single camera-based system to multi-lane
roads.
Road markers classification using binary scanning and slope contoursTELKOMNIKA JOURNAL
Road markers guide the driver while driving on the road to control the traffic for the safety of
the road users. With the booming autonomous car technology, the road markers classification is important
in its vision segment to navigate the autonomous car. A new method is proposed in this paper to classify
five types of road markers namely dashed, single, double, solid-dashed and dashed-solid which are
commonly found on the two lane single carriageway. The classification is using unique feature acquired
from the binary image by scanning on each of the images to calculate the frequency of binary transition.
Another feature which is the slopes between the two centroids which allow the proposed method, to
perform the classification within the same video frame period. This proposed method has been observed to
achieve an accuracy value of at least 93%, which is higher than the accuracy value achieved by
the existing methods.
REVIEW OF LANE DETECTION AND TRACKING ALGORITHMS IN ADVANCED DRIVER ASSISTANC...ijcsit
Lane detection and tracking is one of the key features of advanced driver assistance system. Lane detection is finding the white markings on a dark road. Lane tracking use the previously detected lane markers and adjusts itself according to the motion model. In this paper, review of lane detection and tracking algorithms developed in the last decade is discussed. Several modalities are considered for lane detection which
include vision, LIDAR, vehicle odometry information,information from global positioning system and digital maps. The lane detection and tracking is one of the challenging problems in computer vision.Different vision based lane detection techniques are explained in the paper. The performance of different lane detection and tracking algorithms is also compared and studied.
This document proposes a real-time image processing (RTIP) algorithm to detect vehicle queues at traffic junctions using a low-cost system. The algorithm has two main operations: 1) motion detection using frame differencing and thresholding, and 2) vehicle detection using a Separable Morphological Edge Detector (SMED) operator and thresholding. The algorithm aims to accurately measure queue parameters such as queue length with 95% accuracy. It uses simple spatial-domain techniques for real-time processing with low computational requirements.
Surface generation from point cloud.pdfssuserd3982b1
This document summarizes research on generating 3D surface models from point clouds acquired using a vision-based laser scanning sensor. It discusses using adaptive filters to reduce noise in the point clouds and generating triangular meshes from the point clouds to create an initial surface model. It then covers using NURBS (Non-Uniform Rational B-Splines) to optimize the surface model for accuracy by fitting parametric surfaces to the triangular mesh. The goal is to develop accurate 3D surface models of turbine blades for robotic welding applications to repair flaws.
Enhancement performance of road recognition system of autonomous robots in sh...sipij
This document summarizes a research paper that proposed an algorithm to improve road recognition for autonomous vehicles in shadow scenarios. The researchers conducted experiments to test their algorithm's performance on key metrics like true positive rate and error rate. Their algorithm first converted images to HSV color space to detect shadows, then used normalized difference index and morphological operations to eliminate shadow effects before segmentation and classification. Test results showed their algorithm enhanced road recognition in the presence of shadows, advancing autonomous vehicle navigation capabilities.
LANE CHANGE DETECTION AND TRACKING FOR A SAFE-LANE APPROACH IN REAL TIME VISI...cscpconf
Image sequences recorded with cameras mounted in a moving vehicle provide information
about the vehicle’s environment which has to be analysed in order to really support the driver
in actual traffic situations. One type of information is the lane structure surrounding the vehicle.
Therefore, driver assistance functions which make explicit use of the lane structure represented
by lane borders and lane markings is to be analysed. Lane analysis is performed on the road
region to remove road pixels. Only lane markings are the interests for the lane detection
process. Once the lane boundaries are located, the possible edge pixels are scanned to
continuously obtain the lane model. The developed system can reduce the complexity of vision
data processing and meet the real time requirements.
This document provides an overview of image processing techniques for traffic applications. It discusses automatic lane finding using color-based and texture-based segmentation as well as feature-driven approaches. Object detection methods like thresholding, edge detection using Canny operator, and background differencing are also covered. Additionally, the document proposes an emergency vehicle detection system using red beacon detection and frequency analysis to override normal traffic light patterns when an emergency vehicle is detected.
This document proposes a method for detecting vehicle license plates using vertical edge detection for toll gate applications. It involves binarizing the input image using adaptive thresholding, applying an unwanted line elimination algorithm to enhance the image, and then using vertical edge detection algorithm (VEDA) to detect vertical edges. Candidate plate regions are then extracted and the desired plate is selected. This methodology is intended for use in real-time applications like electronic toll collection systems, where the plate number is extracted and authorization is checked before automatically deducting payment using RFID tags.
Real-Time Video Processing using Contour Numbers and Angles for Non-urban Roa...IJECEIAES
Road users make vital decisions to safely maneuver their vehicles based on the road markers, which need to be correctly classified. The road markers classification is significantly important especially for the autonomous car technology. The current problems of extensive processing time and relatively lower average accuracy when classifying up to five types of road markers are addressed in this paper. Two novel real time video processing methods are proposed by extracting two formulated features namely the contour number, , and angle, 휃 to classify the road markers. Initially, the camera position is calibrated to obtain the best Field of View (FOV) for identifying a customized Region of Interest (ROI). An adaptive smoothing algorithm is performed on the ROI before the contours of the road markers and the corresponding two features are determined. It is observed that the achievable accuracy of the proposed methods at several non-urban road scenarios is approximately 96% and the processing time per frame is significantly reduced when the video resolution increases as compared to that of the existing approach.
Mobile Based Application to Scan the Number Plate and To Verify the Owner Det...inventionjournals
Any License plate recognition system usually passes through three steps of image processing: 1) Extraction of a license plate region; 2) Segmentation of the plate characters; and 3) Recognition of each character. A number of algorithms have been proposed in recent times for efficient disposal of the application. The purpose of this project was to develop a real time application which recognizes number plates from cars at a gate, for example at the entrance of a parking area or a border crossing. The system, based on regular PC with mobile camera, catches video frames which include a visible car number plate and processes them. Once a number plate is detected, its digits are recognized, displayed on the User Interface or checked against a database.The software aspect of the system runs on mobile hardware and can be linked to other applications or databases. It first uses a series of image manipulation techniques to detect, normalize and enhance the Image of the number plate, and then optical character recognition (ocr) to extract the alpha numeric text of number plate. The system are generally deployed in one of two basic approaches: one allows for the entire process to be performed at the lane location in real-time. The other will reveal the driver’s profile by checking in the registered database.
Laser ScanningLaser scanning is an emerging data acquisition techn.pdfanjaniar7gallery
Laser Scanning
Laser scanning is an emerging data acquisition technology that has remarkably broadened its
application field and has been a serious competitor to other surveying techniques. Due to rapid
technological development, the increased accuracy of global positioning systems and improving
demands to even more accurate digital surface models, airborne laser scanning showed
significant development in the 1990s.
Somewhat later terrestrial laser scanning became a reasonable alternative method in many kinds
of applications that previously by ground based surveying or close-range photogrammetry.
1 Airborne laser scanning
Airborne laser scanning is an active remote sensing technology that is able to rapidly collect data
from huge areas. The resulted dataset can be the base of digital surface and elevation models.
Airborne laser scanning is often coupled with airborne imagery, therefore the point clouds and
images can be fused resulting enhanced quality 3D product.
The basic principle is as follows: the sensor emits a laser pulse through the terrain in a
predefined direction and receives the reflected laser beam. Knowing the speed of light, the
distance of the object can be calculated, see Figure 1.
Figure 1.: Time of flight laser range measurement [2]
Airborne LiDAR systems are composed by the following subsystems:
The components are shown in Figure 2
Figure 2.: Principle of airborne LiDAR [2]
2. Sensors, equipment
Sensors can be distinguished based on the scanning method, i.e. how the laser beam is directed
through the surface. The four most widely used sensor types are shown in Figure 4.2.3.
Figure .3: Scanning mechanisms [1]
As it is clearly seen in Figure 3, different kinds of mechanisms are applied by the different types
of sensors; each has its advantages and shortcomings, e.g. number of moving parts, type of
rotation etc. that lead to different kinds of error sources.
The capabilities (repetition rate, scan frequency, scan angle, point density) of the above scanners
are very similar; the main difference lies in the scanning pattern, as seen in Figure 4. The most
widely used oscillating mirror scanners produce the zigzag pattern. Spacing along the line
depends on the pulse rate and scanning frequency, while spacing along the flight direction
depends on the flying speed. To avoid too wide spacing of points along flight direction, LiDAR
flights are usually slower (e.g. at 60-80 m/sec) compared to that of photogrammetric flights
(even 120-160 m/sec). Careful planning of the measurement results in rather homogenous
density, however, due to technical and microelectronic reasons (regarding the operating
mechanism of the mirror, especially in case of oscillating mirrors), higher point density can be
observed at the edges of the scan swath. Previously, critics were addressed to the fixed optic
scanners, i.e. the parallel scan lines along the flight direction can miss sizeable objects, but
vendors successfully responded and modified the mechanis.
This document summarizes a research paper that presents a real-time 3D reconstruction method using stereo vision from a driving car. The method extends LSD-SLAM with stereo capabilities to simultaneously track camera pose and reconstruct semi-dense depth maps. It is evaluated on the KITTI dataset and compared to laser scans and traditional stereo methods. Results show the direct SLAM technique generates visually pleasing and globally consistent semi-dense reconstructions in real-time on a single CPU.
IRJET- Road Recognition from Remote Sensing Imagery using Machine LearningIRJET Journal
This document discusses a framework for recognizing roads from remote sensing imagery using machine learning. It proposes using a convolutional neural network (CNN) trained on large amounts of reference data to initially classify imagery into classification maps, then refining the CNN on a small amount of accurately labeled data. A series of experiments in MATLAB show this two-step training approach considers a large amount of context to provide fine-grained classification maps while addressing issues with imperfect training data. The document also reviews several existing methods for road extraction from remote sensing imagery and their limitations.
1) The document proposes techniques for real-time Indian road analysis using image processing and computer vision, including lane detection, pothole detection, object detection from video, and road sign classification.
2) It discusses using the Hough transform for lane detection, color segmentation and shape modeling with thin spline transformation for road sign classification, and k-means clustering for pothole detection.
3) The techniques are tested on images and video streams from Indian roads to show they can be used for real-time analysis in an automated driver guidance system.
Real time-image-processing-applied-to-traffic-queue-detection-algorithmajayrampelli
This document describes a real-time image processing algorithm for detecting traffic queues. The algorithm uses two operations: motion detection and vehicle detection. Motion detection involves differencing consecutive image frames and comparing the difference to a threshold. Vehicle detection applies edge detection techniques to image profiles. The algorithm aims to measure queue parameters like length, occurrence period, and slope in real-time using low-cost systems. It processes image sub-profiles to reduce computation time. Experimental results found the algorithm could measure queue length with 95% accuracy.
Image Processing Applied To Traffic Queue Detection Algorithmguest673189
This document describes an image processing algorithm for detecting traffic queues using digital video from road cameras. The algorithm has two main operations: 1) motion detection using frame differencing to identify vehicle movement, and 2) vehicle detection using edge detection on image profiles to identify individual vehicles. The algorithm was tested on images captured from cameras at an intersection in College Station, Texas. Key results included accurately measuring queue length, occurrence period, and growth slope to analyze backup traffic forming at red lights.
A Much Advanced and Efficient Lane Detection Algorithm for Intelligent Highwa...cscpconf
This paper presents a much advanced and efficient lane detection algorithm. The algorithm is based on (ROI) Region of Interest segmentation. In this algorithm images are pre-processed by top-hat transform for de-noising and enhancing contrast. ROI of a test image is then extracted. For detecting lines in the ROI, Hough transform is used. Estimation of the distance between Hough origin and lane-line midpoint is made. Lane departure decision is made based on the difference between these distances. As for the simulation part we have used Matlab software.Experiments show that the proposed algorithm can detect the lane markings accurately and quickly.
A Study on Single Camera Based ANPR System for Improvement of Vehicle Number ...journal ijrtem
This document summarizes a study on a single camera-based automatic number plate recognition (ANPR) system to recognize vehicle license plates on multi-lane roads. It proposes a character extraction algorithm using connected vertical and horizontal edge segments to improve recognition rates. The algorithm detects character edge patterns, extracts components by cumulatively labeling edges, and enhances images through contrast adaptive binarization. An ANPR system was installed on a 3-lane test road and achieved a detection rate of 84.6%, though some errors occurred with specific vehicle models or character differences. Further research is needed to handle low-visibility conditions and improve accuracy.
A Study on Single Camera Based ANPR System for Improvement of Vehicle Number ...IJRTEMJOURNAL
In this paper, we introduce the single camera-based number recognition system used for this
system recognizes vehicle number plates on one lane by using a single camera. Intelligent transport system (ITS)
has been constructed because there is a limit in solving traffic problems in a physical manner such as construction
of roads and subways. The single camera-based number recognition system used for this system recognizes vehicle
number plates on one lane by using a single camera. Due to the increased cost of the installation and maintenance
thereof, there is a growing need for a multi-lane-based number recognition system. When the single camera-based
number recognition system is used for multi-lane recognition, the recognition rate is lowered due to a difference in
vehicle image size among lanes and a low-resolution problem. Therefore, in this study, we applied a character
extraction algorithm using connected vertical and horizontal edge segments-based labeling to improve multi-lane
vehicle number recognition rate and thereby to allow application of the single camera-based system to multi-lane
roads.
Road markers classification using binary scanning and slope contoursTELKOMNIKA JOURNAL
Road markers guide the driver while driving on the road to control the traffic for the safety of
the road users. With the booming autonomous car technology, the road markers classification is important
in its vision segment to navigate the autonomous car. A new method is proposed in this paper to classify
five types of road markers namely dashed, single, double, solid-dashed and dashed-solid which are
commonly found on the two lane single carriageway. The classification is using unique feature acquired
from the binary image by scanning on each of the images to calculate the frequency of binary transition.
Another feature which is the slopes between the two centroids which allow the proposed method, to
perform the classification within the same video frame period. This proposed method has been observed to
achieve an accuracy value of at least 93%, which is higher than the accuracy value achieved by
the existing methods.
REVIEW OF LANE DETECTION AND TRACKING ALGORITHMS IN ADVANCED DRIVER ASSISTANC...ijcsit
Lane detection and tracking is one of the key features of advanced driver assistance system. Lane detection is finding the white markings on a dark road. Lane tracking use the previously detected lane markers and adjusts itself according to the motion model. In this paper, review of lane detection and tracking algorithms developed in the last decade is discussed. Several modalities are considered for lane detection which
include vision, LIDAR, vehicle odometry information,information from global positioning system and digital maps. The lane detection and tracking is one of the challenging problems in computer vision.Different vision based lane detection techniques are explained in the paper. The performance of different lane detection and tracking algorithms is also compared and studied.
This document proposes a real-time image processing (RTIP) algorithm to detect vehicle queues at traffic junctions using a low-cost system. The algorithm has two main operations: 1) motion detection using frame differencing and thresholding, and 2) vehicle detection using a Separable Morphological Edge Detector (SMED) operator and thresholding. The algorithm aims to accurately measure queue parameters such as queue length with 95% accuracy. It uses simple spatial-domain techniques for real-time processing with low computational requirements.
Surface generation from point cloud.pdfssuserd3982b1
This document summarizes research on generating 3D surface models from point clouds acquired using a vision-based laser scanning sensor. It discusses using adaptive filters to reduce noise in the point clouds and generating triangular meshes from the point clouds to create an initial surface model. It then covers using NURBS (Non-Uniform Rational B-Splines) to optimize the surface model for accuracy by fitting parametric surfaces to the triangular mesh. The goal is to develop accurate 3D surface models of turbine blades for robotic welding applications to repair flaws.
Enhancement performance of road recognition system of autonomous robots in sh...sipij
This document summarizes a research paper that proposed an algorithm to improve road recognition for autonomous vehicles in shadow scenarios. The researchers conducted experiments to test their algorithm's performance on key metrics like true positive rate and error rate. Their algorithm first converted images to HSV color space to detect shadows, then used normalized difference index and morphological operations to eliminate shadow effects before segmentation and classification. Test results showed their algorithm enhanced road recognition in the presence of shadows, advancing autonomous vehicle navigation capabilities.
LANE CHANGE DETECTION AND TRACKING FOR A SAFE-LANE APPROACH IN REAL TIME VISI...cscpconf
Image sequences recorded with cameras mounted in a moving vehicle provide information
about the vehicle’s environment which has to be analysed in order to really support the driver
in actual traffic situations. One type of information is the lane structure surrounding the vehicle.
Therefore, driver assistance functions which make explicit use of the lane structure represented
by lane borders and lane markings is to be analysed. Lane analysis is performed on the road
region to remove road pixels. Only lane markings are the interests for the lane detection
process. Once the lane boundaries are located, the possible edge pixels are scanned to
continuously obtain the lane model. The developed system can reduce the complexity of vision
data processing and meet the real time requirements.
This document provides an overview of image processing techniques for traffic applications. It discusses automatic lane finding using color-based and texture-based segmentation as well as feature-driven approaches. Object detection methods like thresholding, edge detection using Canny operator, and background differencing are also covered. Additionally, the document proposes an emergency vehicle detection system using red beacon detection and frequency analysis to override normal traffic light patterns when an emergency vehicle is detected.
This document proposes a method for detecting vehicle license plates using vertical edge detection for toll gate applications. It involves binarizing the input image using adaptive thresholding, applying an unwanted line elimination algorithm to enhance the image, and then using vertical edge detection algorithm (VEDA) to detect vertical edges. Candidate plate regions are then extracted and the desired plate is selected. This methodology is intended for use in real-time applications like electronic toll collection systems, where the plate number is extracted and authorization is checked before automatically deducting payment using RFID tags.
Real-Time Video Processing using Contour Numbers and Angles for Non-urban Roa...IJECEIAES
Road users make vital decisions to safely maneuver their vehicles based on the road markers, which need to be correctly classified. The road markers classification is significantly important especially for the autonomous car technology. The current problems of extensive processing time and relatively lower average accuracy when classifying up to five types of road markers are addressed in this paper. Two novel real time video processing methods are proposed by extracting two formulated features namely the contour number, , and angle, 휃 to classify the road markers. Initially, the camera position is calibrated to obtain the best Field of View (FOV) for identifying a customized Region of Interest (ROI). An adaptive smoothing algorithm is performed on the ROI before the contours of the road markers and the corresponding two features are determined. It is observed that the achievable accuracy of the proposed methods at several non-urban road scenarios is approximately 96% and the processing time per frame is significantly reduced when the video resolution increases as compared to that of the existing approach.
Mobile Based Application to Scan the Number Plate and To Verify the Owner Det...inventionjournals
Any License plate recognition system usually passes through three steps of image processing: 1) Extraction of a license plate region; 2) Segmentation of the plate characters; and 3) Recognition of each character. A number of algorithms have been proposed in recent times for efficient disposal of the application. The purpose of this project was to develop a real time application which recognizes number plates from cars at a gate, for example at the entrance of a parking area or a border crossing. The system, based on regular PC with mobile camera, catches video frames which include a visible car number plate and processes them. Once a number plate is detected, its digits are recognized, displayed on the User Interface or checked against a database.The software aspect of the system runs on mobile hardware and can be linked to other applications or databases. It first uses a series of image manipulation techniques to detect, normalize and enhance the Image of the number plate, and then optical character recognition (ocr) to extract the alpha numeric text of number plate. The system are generally deployed in one of two basic approaches: one allows for the entire process to be performed at the lane location in real-time. The other will reveal the driver’s profile by checking in the registered database.
Laser ScanningLaser scanning is an emerging data acquisition techn.pdfanjaniar7gallery
Laser Scanning
Laser scanning is an emerging data acquisition technology that has remarkably broadened its
application field and has been a serious competitor to other surveying techniques. Due to rapid
technological development, the increased accuracy of global positioning systems and improving
demands to even more accurate digital surface models, airborne laser scanning showed
significant development in the 1990s.
Somewhat later terrestrial laser scanning became a reasonable alternative method in many kinds
of applications that previously by ground based surveying or close-range photogrammetry.
1 Airborne laser scanning
Airborne laser scanning is an active remote sensing technology that is able to rapidly collect data
from huge areas. The resulted dataset can be the base of digital surface and elevation models.
Airborne laser scanning is often coupled with airborne imagery, therefore the point clouds and
images can be fused resulting enhanced quality 3D product.
The basic principle is as follows: the sensor emits a laser pulse through the terrain in a
predefined direction and receives the reflected laser beam. Knowing the speed of light, the
distance of the object can be calculated, see Figure 1.
Figure 1.: Time of flight laser range measurement [2]
Airborne LiDAR systems are composed by the following subsystems:
The components are shown in Figure 2
Figure 2.: Principle of airborne LiDAR [2]
2. Sensors, equipment
Sensors can be distinguished based on the scanning method, i.e. how the laser beam is directed
through the surface. The four most widely used sensor types are shown in Figure 4.2.3.
Figure .3: Scanning mechanisms [1]
As it is clearly seen in Figure 3, different kinds of mechanisms are applied by the different types
of sensors; each has its advantages and shortcomings, e.g. number of moving parts, type of
rotation etc. that lead to different kinds of error sources.
The capabilities (repetition rate, scan frequency, scan angle, point density) of the above scanners
are very similar; the main difference lies in the scanning pattern, as seen in Figure 4. The most
widely used oscillating mirror scanners produce the zigzag pattern. Spacing along the line
depends on the pulse rate and scanning frequency, while spacing along the flight direction
depends on the flying speed. To avoid too wide spacing of points along flight direction, LiDAR
flights are usually slower (e.g. at 60-80 m/sec) compared to that of photogrammetric flights
(even 120-160 m/sec). Careful planning of the measurement results in rather homogenous
density, however, due to technical and microelectronic reasons (regarding the operating
mechanism of the mirror, especially in case of oscillating mirrors), higher point density can be
observed at the edges of the scan swath. Previously, critics were addressed to the fixed optic
scanners, i.e. the parallel scan lines along the flight direction can miss sizeable objects, but
vendors successfully responded and modified the mechanis.
This document summarizes a research paper that presents a real-time 3D reconstruction method using stereo vision from a driving car. The method extends LSD-SLAM with stereo capabilities to simultaneously track camera pose and reconstruct semi-dense depth maps. It is evaluated on the KITTI dataset and compared to laser scans and traditional stereo methods. Results show the direct SLAM technique generates visually pleasing and globally consistent semi-dense reconstructions in real-time on a single CPU.
IRJET- Road Recognition from Remote Sensing Imagery using Machine LearningIRJET Journal
This document discusses a framework for recognizing roads from remote sensing imagery using machine learning. It proposes using a convolutional neural network (CNN) trained on large amounts of reference data to initially classify imagery into classification maps, then refining the CNN on a small amount of accurately labeled data. A series of experiments in MATLAB show this two-step training approach considers a large amount of context to provide fine-grained classification maps while addressing issues with imperfect training data. The document also reviews several existing methods for road extraction from remote sensing imagery and their limitations.
1) The document proposes techniques for real-time Indian road analysis using image processing and computer vision, including lane detection, pothole detection, object detection from video, and road sign classification.
2) It discusses using the Hough transform for lane detection, color segmentation and shape modeling with thin spline transformation for road sign classification, and k-means clustering for pothole detection.
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1. Using 3D laser profiling sensors for the automated measurement of road
surface conditions (ruts, macro-texture, raveling, cracks).
John Laurent1, Jean François Hébert1, Daniel Lefebvre2, Yves Savard3
1
Pavemetrics Systems inc., Canada
2
INO (National Optics Institute), Canada
3
Ministère des Transports du Québec (MTQ), Canada
Abstract: In order to maximize road maintenance funds and optimize the condition of road networks, pavement
management systems need detailed and reliable data on the status of the road network. To date, reliable crack
and raveling data has proven difficult and expensive to obtain. To solve this problem, over the last 10 years[1][2]
Pavemetrics inc. in collaboration with INO (National Optics Institute of Canada) and the MTQ (Ministère des
Transports du Québec) have been developing and testing a new 3D technology called the LCMS (Laser Crack
Measurement System).
The LCMS system was tested at the network level to evaluate the system’s performance at the task of automatic
detection and classification of cracks. The system was compared to manual results over 9000 km to be 95%
correct in the general classification of cracks.
1. INTRODUCTION
The LCMS is composed of two high performance 3D laser profilers that are able to measure complete transverse
road profiles with 1mm resolution at highway speeds. The high resolution 2D and 3D data acquired by the
LCMS is then processed using algorithms that were developed to automatically extract crack data including
crack type (transverse, longitudinal, alligator) and severity. Also detected automatically are ruts (depth, type),
macro-texture (digital sand patch) and raveling (loss of aggregates). This paper describes results obtained
recently regarding road tests and validation of this technology.
2. HARDWARE CONFIGURATION
The sensors used with the LCMS system are 3D laser profilers that use high power laser line projectors, custom
filters and a camera as the detector. The light stripe is projected onto the pavement and its image is captured by
the camera. The shape of the pavement is acquired as the inspection vehicle travels along the road using a signal
from an odometer to synchronize the sensor acquisition. All the images coming from the cameras are sent to the
frame grabber to be digitized and then processed by the CPU. Saving the raw images would imply storing nearly
30Gb per kilometer at 100 km/h but using lossless data compression algorithms on the 3D data and fast JPEG
compression on the intensity data brings the data rate down to a very manageable 20Mb/s or 720Mb/km.
Figure 1. LCMS on an inspection vehicle (left), laser profiling of cracks (right)
2. Table I - LCMS Specifications
Nbr. of laser profilers 2
Sampling rate (max.) 11,200 profiles/s
Vehicle speed 100 km/h (max)
Profile spacing Adjustable
3D points per profile 4096 points
Transverse field-of-view 4m
Depth range of operation 250 mm
Z-axis (depth) accuracy 0.5 mm
X-axis (transverse) resolution 1 mm
Figure 2. Photo of the LCMS System (Sensors and Controller)
The LCMS sensors simultaneously acquire both range and intensity profiles. The figure below illustrates how
the various types of data collected by the LCMS system can be exploited to characterize many types of road
features. The graph shows that the 3D data and intensity data serve different purposes. The intensity data is
required for the detection of lane markings and sealed cracks whereas the 3D data is used for the detection of
most of the other features.
Figure 3. Data analysis library diagram
2
3. 3. INTENSITY DATA
Intensity profiles provided by the LCMS are used to form a continuous image of the road surface. The first role
of the intensity information is for the detection of road limits. This algorithm relies on the detection of the
painted lines used as lane markings to determine the width and position of the road lane in order to compensate
for driver wander. The lane position data is then used by the other detection algorithms to circumscribe the
analysis within this region of interest in order to avoid surveying defects outside the lane. Highly reflective
painted landmarks are much easier to detect in 2D since they generally appear highly contrasted in the intensity
images. With the proper pattern recognition algorithms, various markings can be identified and surveyed. The
following figure shows the results of the different types of images (intensity, range, and 3D merged image) that
can be produced from the LCMS data.
Figure 4. LCMS Data type – Range (left) – Intensity (center) – 3D merged (left)
4. 3D RANGE DATA
The 3D data acquired by the LCMS system measures the distance from the sensor to the surface for every
sampled point on the road. The previous image (above left) shows a range data image acquired by the sensors. In
this image, elevation has been converted to a gray level. The darker the point, the lower is the surface. In a range
image the height can vary along the cross section of the road. The areas in the wheel path can be deeper than the
sides and thus appear darker this would correspond to the presence of ruts. Height variations can also be
observed in the longitudinal direction due to variations in longitudinal profiles of the road causing movements in
the suspension of the vehicle holding the sensors. These large-scale height variations correspond to the low-
spatial frequency content of the range information in the longitudinal direction. Most features that need to be
detected are located in the high-spatial frequency portion of the range data. The figure below shows a 2m (half
lane) transverse profile where the general depression of the profile corresponds to the presence of a rut, the sharp
drop in the center of the profile corresponds to a crack point and the height variations (in blue) around the red
line correspond to the macro-texture of the road surface.
Figure 5. LCMS (half lane) 2m transverse profile showing ruts, cracks and texture.
3
4. 5. MACRO-TEXTURE
Macrotexture is important for several reasons, for example it can help estimate the tire/road friction level, water
runoff and aquaplaning conditions and tire/road noise levels produced just to name a few. Macrotexture can be
evaluated by applying the ASTM 1845-01norm. This standard requires the calculation of the mean profile depth
(MPD). To calculate the MPD, the profile is divided into small (10cm) segments and for each segment a linear
regression is performed on the data. The MPD is then computed as the difference between the highest point on
the profile and the average fitted line for the considered portion. MPD is the only way possible to evaluate
texture using standard single point (64kHz) laser sensors. The LCMS however acquires sufficiently dense 3D
data to not only measure standard MPD but also to evaluate texture using a digital model of the sand patch
method (ASTM E965).
Figure 6. MPD vs Sand Patch
The digital sand patch model is calculated using the following proposed Road Porosity Index (RPI). The RPI
index is defined as the volume of the voids in the road surface that would be occupied by the sand (from the sand
patch method) divided by a surface area. The digital sand patch method implemented allows texture to be
evaluated continuously over the complete road surface instead of measuring only a single point inside a wheel
path. The RPI can be calculated over any user definable surface area but LCMS reports by default the macro-
texture values within the 5 standard AASHTO bands (center, right and left wheel paths and outside bands).
Figure 7. MPD vs Digital Sand Patch (RPI)
Results show (see figure below) that RPI measurements using the LCMS are highly repeatable as shown by road
tests on several Alabama test sections and that RPI closely matches MPD measurements collected by standard
texture lasers over a wide range of texture values.
4
5. Figure 8. Digital Sand Patch (RPI) accuracy and repeatability results (Alabama tests).
6. RAVELING
Raveling is the wearing away of the pavement surface caused by the dislodging of aggregate particles and loss of
asphalt binder that ultimately leads to a very rough and pitted surface with obvious loss of aggregates. In order to
detect and quantify raveling conditions a Raveling Index (RI) indicator is proposed. The RI is calculated by
measuring the volume of aggregate loss (holes due to missing aggregates) per unit of surface area (square meter).
With the LCMS the high resolution of the 3D data allows for the detection of missing aggregates. Algorithms
designed to specifically detect aggregate loss were developed in order to evaluate the RI index automatically.
The figures below demonstrate the results of aggregate detection (in blue) on range images. The next series of
images show an example of a high RI rated road section measured on porous asphalt roads in the Netherlands.
Finally, the results of a repeatability test (3 passes) also on road sections in the Netherlands is shown.
Figure 9. Example of the automatic detection of aggregate loss in range images.
5
6. Figure 10. Example of high RI road section on porous asphalt roads in the Netherlands.
Figure 11. Repeatability of RI measurements (3 passes) on road sections in the Netherlands.
7. CRACKING
Detecting cracks reliably is far more complex than applying a threshold on a range image. As mentioned
previously the 3D profile data needs to be detrended from the effects of rutting and vehicle movements.
Macrotexture is also a problem; road surfaces have very variable macrotexture from one section to the next and
even from one side of the lane to the other. For example, on roads with weak macrotexture we can hope to detect
very small cracks which will be harder to detect on more highly textured surfaces. It is thus necessary to evaluate
and to adapt the processing operations based on the texture and type of road surface. Once the detection
operation is performed, a binary image is obtained where the remaining active pixels are potential cracks. This
binary image is then filtered to remove many of the false detections which are caused by asperities and other
features in the road surface which are not cracks on the pavement. At this point in the processing, most of the
remaining pixels can correctly be identified to existing cracks, however many of these crack segments need to be
joined together to avoid multiple detections of the same crack. After the detection process, the next step consists
in the characterization of the cracks. The severity level of a crack is determined by evaluating its width (opening)
typically cracks will be separated in low, medium and high severity levels. The cracks also need to be grouped
6
7. into two main categories: Longitudinal and transverse cracks. Furthermore, transverse cracks are further divided
into complete and incomplete types and joints need to be classified separately. Longitudinal cracks are further
refined into three sub-categories: simple, multiple and alligator.
The LCMS system was used by the MTQ to survey nearly10,000km of its road network. In order to validate the
system an independent 3rd party under the supervision of the MTQ was mandated to manually qualify the crack
detection results of the LCMS system over the entire survey. To do this each 10m section was visually analyzed
and the results were categorized in 3 classes (Good, Average and Bad). A forth class (NA) was used when for
when it was not possible to correctly evaluate a section. Figure 8 shows an example of crack detection results on
a 10m pavement section. Transverse cracks are identified with a bounding box. Regions in red indicate high
severity cracks (15mm+) and light blue and green represent low severities (less than 5mm). Table 3 shows the
results of the compilation of the manual evaluation. The final results are deemed excellent by the MTQ as the
overall ‘Good’ rating reaches 96.5%. Repeatability tests were also conducted on several MTQ test sections and
the results shown on the graphs below also demonstrate very repeatable crack detection results on these sections.
Figure 12. Example crack detection results (severity = color code)
Table II - 10,000 km automatic vs manual survey results
Results (manual classification)
Total
District # Number of images (10m sections) Proportion (%)
(10 m sections)
Good Average Bad NA Good Average Bad NA
84 35288 34144 310 144 690 96,8 0,9 0,4 2,0
85 4243 4101 53 51 38 96,7 1,2 1,2 0,9
86 147903 144040 516 1520 1827 97,4 0,3 1,0 1,2
87 149926 138453 1170 5728 4575 92,3 0,8 3,8 3,1
88 189097 183010 1064 2002 3021 96,8 0,6 1,1 1,6
89 125003 121835 442 2015 711 97,5 0,4 1,6 0,6
90 123653 116930 2980 2434 1309 94,6 2,4 2,0 1,1
91 & 92 215513 213142 197 956 1218 98,9 0,1 0,4 0,6
Total 990626 955655 6732 14850 13389 96,5 0,7 1,5 1,4
7
8. Figure 13. Repeatability results (3 passes) on two MTQ road sections.
8. CONCLUSIONS
We have presented a road surveying system that is based on two high performance transverse 3D laser profilers
that are placed at the rear of an inspection vehicle looking down in such a way as to scan the entire 4m width of
the road surface with 1mm resolution. This configuration allows the direct measurement of many different types
of surface defects by simultaneously acquiring high resolution 3D and intensity data. Examples of different
algorithms and results were shown using the 3D data to detect cracks, ruts, evaluate macro-texture and to detect
raveling while the intensity data was used for the detection of lane markings.
The LCMS system was tested at the network level (10000km) to evaluate the system’s performance at the task of
automatic detection and classification of cracks. The system was evaluated to be over 95% correct in the general
classification of cracks.
A Road Porosity Index (RPI) was proposed as a model to measure the equivalent of a digital sand patch. The
digital sand patch (RPI) method implemented allows texture to be evaluated continuously over the complete road
surface and within each of the five AASHTO bands.
A Raveling Index (RI) indicator calculated by measuring the volume of aggregate loss (holes due to missing
aggregates) per unit of surface area (square meter) was proposed. This indicator was shown to allow the
quantification of the amount of raveling present and was shown to be highly repeatable.
REFERENCES
[1] Laurent, J., Lefebvre, D., Samson E., 2008. Development of a New 3D Transverse Profiling System for the
Automatic Measurement of Road Cracks. Proceedings of the 6th Symposium on Pavement Surface
Caracteristics, Portoroz, Slovenia.
[2] Laurent, J., Hébert JF., 2002. High Performance 3D Sensors for the characterization of Road Surface
Defects. Proceedings of the IAPR Workshop on Machine Vision Applications, Nara Japan.
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