Summary: | 碩士 === 國立中正大學 === 電機工程研究所 === 102 === The visually impaired people lose their vision and are apt to be in danger when situated in unfamiliar environments or confronted with moving object. This study proposes an environment and obstacle detection system for the blind based on the Kinect sensors. This system aims to assist the visually impaired avoiding when they explore the environments.
We used Kinect sensors to obtain the environment information. Digital image processing techniques were applied to process the color and depth images generated by the Kinect sensors. This research can be separated into three parts. In the first part, we processed the depth image to detect stair and concave ground in the indoor environment. Morphology preprocessors were used to eliminate noises in the depth images. Then we use Canny edge detection and Hough transform were employed to search for line patterns. Finally constraints were set to determine the appearance of these two scenes. The second part was obstacle detection in the indoor environment based on depth images. We used morphology as preprocessors to eliminate noise. Then we obtained obstacle candidates by using region growing. Finally four rules were used to determine if the candidates were real obstacles. The third part was obstacle detection in the outdoor environment based on color images. Peak-and-Valley filter was used as the preprocessor. Then Canny edge detection and Hough transform were used to detect the vertical lines for possible position of the seeds for the following region growing process. We obtained the obstacle candidate by using region growing. Finally principles were set to determine if the candidates were real obstacles or not.
After tested in the scenes of different environments and obstacles, we demonstrated the capability of this system in detecting obstacles in the indoor and outdoor environments. It can also recognize the stair and concave ground scenes. The visually impaired is able to know the position and distance of the obstacles, stairs, and concave ground through the vibration module and sound alert. The processing time of this system is 0.4 sec per frame, a speed which is fast enough for real time assistant system for the blind.
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