Detect concrete cracks based on OTSU algorithm with differential image

Aiming at the detection of concrete surface cracks, based on digital image processing technology, OTSU algorithm is processed based on differential image. First, the Gaussian filter is acted on the original image to obtain the smoothed image. Then the smoothed image is subtracted by the original image, the differential image is obtained. According to the OTSU algorithm, the optimal threshold on the differential image was calculated. As the characteristic cracks are a few pixels and with lower grey values, the pixels whose grey values are less than the mean value of the whole image to get the best threshold value were only calculated. Finally, remove the background noise based on the morphologic noise reduction to obtain the binary image of the crack. The experimental results show that the cracks can be discerned in complex backgrounds.