212 research outputs found

    Lane Line Detection and Object Scene Segmentation Using Otsu Thresholding and the Fast Hough Transform for Intelligent Vehicles in Complex Road Conditions

    Get PDF
    An Otsu-threshold- and Canny-edge-detection-based fast Hough transform (FHT) approach to lane detection was proposed to improve the accuracy of lane detection for autonomous vehicle driving. During the last two decades, autonomous vehicles have become very popular, and it is constructive to avoid traffic accidents due to human mistakes. The new generation needs automatic vehicle intelligence. One of the essential functions of a cutting-edge automobile system is lane detection. This study recommended the idea of lane detection through improved (extended) Canny edge detection using a fast Hough transform. The Gaussian blur filter was used to smooth out the image and reduce noise, which could help to improve the edge detection accuracy. An edge detection operator known as the Sobel operator calculated the gradient of the image intensity to identify edges in an image using a convolutional kernel. These techniques were applied in the initial lane detection module to enhance the characteristics of the road lanes, making it easier to detect them in the image. The Hough transform was then used to identify the routes based on the mathematical relationship between the lanes and the vehicle. It did this by converting the image into a polar coordinate system and looking for lines within a specific range of contrasting points. This allowed the algorithm to distinguish between the lanes and other features in the image. After this, the Hough transform was used for lane detection, making it possible to distinguish between left and right lane marking detection extraction; the region of interest (ROI) must be extracted for traditional approaches to work effectively and easily. The proposed methodology was tested on several image sequences. The least-squares fitting in this region was then used to track the lane. The proposed system demonstrated high lane detection in experiments, demonstrating that the identification method performed well regarding reasoning speed and identification accuracy, which considered both accuracy and real-time processing and could satisfy the requirements of lane recognition for lightweight automatic driving systems

    Probabilistic Lane Association

    Get PDF
    Lane association is the problem of determining in which lane a vehicle is currently driving, which is of interest for automated driving where the vehicle must understand its surroundings. Limited to highway scenarios, a method combining data from different sensors to extract information about the currently associated lane is presented. The suggested method splits the problem in two main parts, lane change identification and road edge detection. The lane change identification mainly uses information from the camera to model the lateral movement on the road and identifies the lane changes as a relative position on the road. This part is implemented with a particle filter. The road edge detection enters radar detections to an iterated Kalman filter and estimates the distances to the road edges. Finally, a combination of the filter outputs makes it possible to compute an absolute position on the road. Comparing the relative and absolute positioning then leads to the desired lane association estimate. The results produced are reliable and encourages to continue approaching this problem in a similar manner, but the current implementation is computationally heavy

    A Hybrid Vision-Map Method for Urban Road Detection

    Get PDF

    Road terrain detection for Advanced Driver Assistance Systems

    Get PDF
    Kühnl T. Road terrain detection for Advanced Driver Assistance Systems. Bielefeld: Bielefeld University; 2013

    Road Scene Interpretation for Autonomous Navigation Fusing Stereo Vision and Digital Maps

    Get PDF
    En esta tesis se ha presentado un método de detección de carretera basado en visión estereoscópica. El aprendizaje automático se utiliza para resolver problemas de visión artificial de muy diferente ámbito, en concreto, la técnica utilizada en este caso es la llamada boosting, la cual utiliza árboles de decisión para clasificar cada píxel de la imagen como zona que pertenece carretera o no. El vector de características utilizado incluye información proporcionada por mapas digitales, visión estéreo y cámaras en color y en escala de grises. La imagen en escala de grises es utilizada para detectar marcas viales, Local Binary Patterns (LBP) y Histogramas de Orientación de Gradiente (HOG). Las cámaras en color son utilizadas para el cálculo de una imagen que es invariante a la iluminación y también para detectar las sombras presentes en la imagen. Además, se ha desarrollado un método basado en el espacio de color HSV para detectar las zonas de vegetación presentes en la escena. Las cámaras estéreo tienen un papel importante porque son las encargadas de proporcionar información 3D al sistema. Algunas de las características que usan dicha información son los vectores normales y los valores de curvatura. Se ha desarrollado un nuevo método para la detección de bordillos. Este novedoso detector de bordillos se basa en el análisis de la curvatura porque describe la variación de la forma de la carretera incluso en presencia de pequeños bordillos. La función es capaz de detectar bordillos de 3 cm de altura incluso hasta 20 metros de distancia, siempre y cuando los píxeles que pertenecen al bordillo estén conectados entre si en la imagen de curvatura. Otros obstáculos como vehículos, muros o arboles son también detectados utilizando visión estereoscópica. Una nueva forma para convertir características que describen limites de carretera en características que describen zonas de carretera se ha descrito en esta tesis. Utiliza marcas viales, bordillos, obstáculos y zonas de vegetación como entradas y tras incluir información adicional del mapa se genera un modelo de carretera. La originalidad de este sistema es el punto desde donde se detecta es espacio libre. %Otros métodos crean lineas desde el punto medio del limite inferior de la imagen hasta que la linea llega a un obstáculo, pero nuestra propuesta utiliza otro punto de vista porque sus lineas empiezan desde el punto de fuga y los valores de las características de van acumulando a lo largo de dicha linea. Otra característica muy importante es la obtenida a partir de los mapas digitales. El objetivo es conseguir un imagen a priori de la forma de la carretera basado en la posición actual del vehículo y la información de las calles proporcionada por el mapa. La incertidumbre sobre los errores de posicionamiento son tenidos en cuenta durante el proceso y la anchura de la carretera es correctamente detectada usando el modelo radial propuesto. Se han realizado múltiples pruebas con diferentes clasificadores y parámetros basados en arboles de decisión para posteriormente elegir el clasificador que mejor funciona en la detección de carretera. El resultado de la clasificación es utilizado en un CRF para filtrar la respuesta y obtener un resultado mas suave. La métrica utilizada para evaluar los clasificadores es el F-score. El sistema es evaluado en el plano imagen, el cual es el método mas común en la literatura. Sin embargo, en un escenario de conducción autónoma, el control se realiza normalmente en una imagen a vista de pájaro de la escena. Se ha adoptado el mismo método de evaluación que se utiliza en la comparador internacional de algoritmos KITTI para poder comparar nuestros resultados con otros algoritmos

    An evaluation of innovative countermeasures for pedestrian safety

    Full text link
    The objective of this research was to evaluate the effectiveness of innovative countermeasures deployed to help improve pedestrian safety and walkability. Potential countermeasures evaluated in this research include: (1) a portable speed trailer, (2) a high visibility crosswalks, (3) advance yield markings, (4) yield here to pedestrians signs, (5) in-roadway knockdown signs, (6) danish offsets, (7) median refuges, (8) intelligent transportation system (ITS) based automatic pedestrian detection device, (9) smart lighting, (10) pedestrian activated flashing lights; A before-and-after analysis strategy was be used to evaluate the selected countermeasures. Measures of effectiveness (MOEs) identified to evaluate the impacts of these countermeasures, include pedestrians\u27 and motorists\u27 behaviors. Data were collected immediately prior to the installation of each countermeasure during AM and PM peak periods and two weeks after the installation of each countermeasure. The results were evaluated for their statistical significance; Results from the analyses of the data showed that the installation of high visibility crosswalk, advance yield markings, yield here to pedestrians signs, median refuge, danish offset, in-roadway knockdown signs were effective in the following ways: increase motorists\u27 yielding, diverted pedestrians, pedestrians who look for vehicles before beginning to cross and before crossing second half of the street. These countermeasures also resulted in fewer vehicles blocking the crosswalk, reducing average pedestrian delay and decreasing the number of pedestrians trapped in the roadway. Also, drivers yielded at greater distances upstream of the crosswalk. The average vehicle speed was reduced upstream and downstream of the location of the portable speed trailer. The installation of ITS based automatic pedestrian detection device and smart lighting resulted in fewer pedestrians trapped in the roadway and increased driver yielding behavior. The countermeasures at a mid-block location showed positive safety benefits in motorists\u27 and pedestrians\u27 behaviors; The improvements in MOEs for both motorists\u27 and pedestrians\u27 behaviors are positive and statistically significant in most cases. The findings from this research may be of value to other regions with similar characteristics

    Biologically inspired composite image sensor for deep field target tracking

    Get PDF
    The use of nonuniform image sensors in mobile based computer vision applications can be an effective solution when computational burden is problematic. Nonuniform image sensors are still in their infancy and as such have not been fully investigated for their unique qualities nor have they been extensively applied in practice. In this dissertation a system has been developed that can perform vision tasks in both the far field and the near field. In order to accomplish this, a new and novel image sensor system has been developed. Inspired by the biological aspects of the visual systems found in both falcons and primates, a composite multi-camera sensor was constructed. The sensor provides for expandable visual range, excellent depth of field, and produces a single compact output image based on the log-polar retinal-cortical mapping that occurs in primates. This mapping provides for scale and rotational tolerant processing which, in turn, supports the mitigation of perspective distortion found in strict Cartesian based sensor systems. Furthermore, the scale-tolerant representation of objects moving on trajectories parallel to the sensor\u27s optical axis allows for fast acquisition and tracking of objects moving at high rates of speed. In order to investigate how effective this combination would be for object detection and tracking at both near and far field, the system was tuned for the application of vehicle detection and tracking from a moving platform. Finally, it was shown that the capturing of license plate information in an autonomous fashion could easily be accomplished from the extraction of information contained in the mapped log-polar representation space. The novel composite log-polar deep-field image sensor opens new horizons for computer vision. This current work demonstrates features that can benefit applications beyond the high-speed vehicle tracking for drivers assistance and license plate capture. Some of the future applications envisioned include obstacle detection for high-speed trains, computer assisted aircraft landing, and computer assisted spacecraft docking
    corecore