Research On Technique Of Pretreatment And Small Target Detection Of Sea-sky Background IR Image

At present, because the detection for small targets is an important research aspect in signal processing field, many scholars are engaging the research of detection for small targets. The effective detection for small targets in low SNR images is still a hot research field. In order to improve the detection ratio of small targets and decrease the false alarming ratio in the condition of sea-sky background, the paper refers to the technology of pretreatment of IR images and the technology of detection of small targets, mainly including the technology of sea-sky background segmentation and the technology of small targets detection based on the spatial matched filtering.At first, the importance and necessity of studying the technology of image pretreatment and small targets detection has been introduced. At the same time, we have introduced the main technologies of image pretreatment, and made a comparison of those technologies.Secondly, we have studied the technology of background segmentation in sea-sky background IR images, and put forward four kinds sea-sky background segmentation methods. Because the histogram of sea-sky background IR image has two peaks and one vale, utilizing the character of the histogram, we put forward the method of sea-sky background segmentation based on statistical histogram. According to the difference of grayness distributing between sea background and sky background, a method of sea-sky background segmentation based on row mean value has been raised. When the grads of the sea-sky line has been considered, a method of sea-sky background segmentation based on the mean value of grads intensity has been put forward. If we consider the information of the boundary of sea background and sky background, we raise the method of sea-sky background segmentation based on the sea-sky line.Based on the study of the technology of sea-sky background segmentation, the technology of background suppression and small targets detection based on spatial matched filtering has been studied. The analysis of experiment results indicates the effect of spatial matched filtering based on background segmentation is very good.At last, we have summarized the main work in the paper.