الفهرس 
صفحة العنوانOnly 14 pages are availabe for public view
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Abstract
Pavement distresses determine the road condition, which are an important
measure for road maintenance and rehabilitation. Cracks are the most common
road pavement surface defects. This thesis has proposed an automatic system
(toolbox) that used for crack detection, crack type characterization and severity
level assignment to each detected crack and being able to characterize different
crack types in a given image. The toolbox based on Images data produced by
the Mobile Laser Scanner system ”MLS” with two additional digital cameras of
resolution 25 MPIX. It follows a set of guidelines based on the Distress Catalog
.’”
of the Egyptian Code for urban and Rural Roads Works. In addition, it
calculates Pavement Condition Index (PCI), and predict a deterioration model
for flexible road pavement surface. The toolbox consisted of seven stages:
The first stage is the preprocessing of images, aims to prepare the images for
crack detection. Images are smoothed to reduce high variance of pixel
intensities found in typical road pavement surface images, without affecting or
deteriorating cracks pixels’ intensities by using algorithms such as anisotropic
diffusion and morphological smoothing. Then, they undergo an intensity
normalization process to reduce the problem of non-uniform background
illumination, followed by an intensity saturation process that is applied to
reduce the specular reflections on some surface materials (bright pixels).
The second stage: is concerned with crack detection where pre-processed
images are segmented, based on an intensity threshold automatically computed
for each image, to distinguish between crack pixels and image background.
The third stage: it deals with crack type characterization with another
classification technique that is constructed to characterize the detected cracks.
Orienting the Mobile Laser Scanner for Building the Required Database of Pavement Maintenance