Abstract: As for an image with different gray values in the object and the background,in order to separate the object from the background,the minimum of the histogram is often used as the threshold to separate the image.In this paper,a new method is adopted based on neural network’s linear searching to determine the minimum of histogram.Through this method the optimal threshold is obtained and the instability and the unreliability of the minimum are conquered,which are determined by the thresholding metheod of the minimum.Experimental results show that adopting this new method to search for the minimum can obtain the absolute minimum,and using the optimal value to segment the image can separate the object from the background and get the satisfactory results.

Key words: image processing； histogram； linear searching； golden section searching； thresholding segmentation；