There is a great need for the introduction of advanced technology and equipment to improve the existing ways of traffic control as the problem of urban traffic congestion spreads. The traffic problems are increasing nowadays due to the growing number of vehicles and the limited resources we are provided by the infrastructures.
The most improved system available for traffic control is controlling the traffic light by image processing. It detects vehicle by images instead of using sensors. Image sequences will be captured by a camera placed along with the traffic light and the sequences will then be analyzed using digital image processing.
This system consists of a hardware module, a software module and an interfacing component. The hardware module consists of the following:
A USB based web camera is used in this project as an image sensor. A central unit is required for the various image processing tasks and a general purpose PC serves the purpose. It should also have a platform consisting of a few toy vehicles and LEDs which serve as the prototype of the real world traffic light control system.
The software module has a MATLAB version 7.8 as the image processing software comprising of specialized modules to perform specific tasks.
The interfacing between the hardware and software is done using parallel port of the personal computer.
The process involves image acquisition, RGB to grey conversion, image enhancement and image matching using edge detection.
Image acquisition is initially done by using web camera. The captured images are subjected to RGB to grey conversion. The acquired image in RGB is first converted to grey and then the image is brought in contrast to the background so that a proper threshold level can be selected while carrying out the binary conversion. Here comes the need of image enhancement techniques.
The objective of image enhancement technique is to process an image so that result is more suitable than the original image for the specific application.
Among the key features of an image which are edges, lines and points, edge is used in this system which can be detected from the abrupt changes I the gray level. An edge essentially demarcates between two distinctly different regions. That is an edge is the border between two different regions. This method locates the pixels in the image that correspond to the edges of the objects seen in the image.
Image processing is a better technique to control the state change of the traffic light. It can reduce the traffic congestion and avoids the time being wasted by a green light on an empty road. As it visualizes the reality, it functions much better than those systems that rely on the detection of the vehicles’ metal content.