Automatic analysis of fuel spray images

Abstract Analysis of fuel spray droplets is being conducted in General Motors Research Laboratories to provide real-time information on in-focus droplet sizes and numerical density. This paper introduces a fast and efficient technique for automatic analysis of fuel spray images. The preprocessing stage consists of a global thresholding of the log-edge of the image. The thresholded image is then used as a reference to detect objects in the gray level image, and the recognition of in- and out-of-focus droplets is achieved through a 3-level tree classifier.