| 摘要 |
The subject of the invention is a method for detecting and classifying events of a scene by means of a single-pupil imaging system equipped with a VisNIR detector in the 0.6 μm-1.1 μm band and with an SWIR detector, which comprises steps of acquiring synchronized VisNIR and SWIR successive 2D images, of displaying the VisNIR images, and of processing these images, which consists in: comparing the SWIR images so as to determine, for each pixel, the variation in illumination from one SWIR image to another and the peak value of these SWIR illuminations, if this variation in SWIR illumination is greater than a threshold, then an event associated with said pixel is detected and: its date, its temporal shape and its duration are determined, in the VisNIR images, the coordinates are determined of the corresponding pixel for which: the variation in the illumination from one VisNIR image to another and the peak value of these VisNIR illuminations are calculated, and these variations in SWIR and VisNIR illumination and their peak values are compared so as to estimate a temperature of the event, the distance of the corresponding point of the scene is estimated so as to calculate the intensity of the event on the basis of the SWIR and VisNIR illuminations and on the basis of this distance, the total energy of the event is estimated on the basis of its temporal shape and of its intensity, the event is classified as a function of its duration, its temperature, its intensity and its energy, the previous steps are repeated for another pixel of the SWIR images. |
| 主权项 |
1. A method for detecting and classifying events of firing threats type of a scene by means of a single-pupil imaging system mounted on a mobile platform and equipped with several detectors, including a detector in the 0.6 μm-1.1 μm wavelength band termed the VisNIR detector and a detector in the 0.9 μm-1.7 μm wavelength band termed the SWIR detector, associated with a processing unit, which comprises a step of acquiring successive 2D images of the scene which arise from the VisNIR detector, termed VisNIR images, and successive 2D images of the scene which arise from the SWIR detector and are synchronized with the VisNIR images, termed SWIR images, a step of displaying the VisNIR images, and a step of processing the VisNIR and SWIR images via the processing unit, wherein this step of processing the images comprises the following sub-steps:
comparing the successive SWIR images so as to determine, for each pixel (x1,y1) and neighboring pixels, the variation in illumination from one SWIR image to another and the peak value e1(t) of these so-called SWIR illuminations, if this variation in SWIR illumination is greater than a predetermined illumination threshold, then the variation in SWIR illumination during which said threshold is exceeded is designated as the signature of an event i and an event is associated with said pixel (x1,y1) or with the barycenter of the pixels considered, and the step of processing the images further comprises the sub-steps of:
determining the date ti of the event i,determining the temporal shape and the duration δti of the signature of the event (step A),determining the coordinates of the pixel (x2,y2) and of the neighboring pixels corresponding to the pixel (x1,y1) or to the barycenter are determined in the VisNIR images synchronized with the SWIR images, and for this pixel (x2,y2) and these neighboring pixels:
calculating the variation in the illumination from one VisNIR image to another and the peak value e2(t) of these so-called VisNIR illuminations, and comparing these variations in SWIR and VisNIR illumination and their peak values e1(t) and e2(t) so as to estimate a temperature of the event on the basis of a predetermined lookup table (step B),
if the scene is a daytime scene and the temperature is greater than a temperature threshold, then the event is a false alarm (step C) and the previous steps are repeated with another pixel,otherwise:estimating the distance Ri of the corresponding point of the real-time scene on the basis of measurements of angular speeds of elements of the scene, of the speed of the platform and of the VisNIR images,calculating the intensity I; of the event i on the basis of the SWIR and VisNIR illuminations of this pixel and on the basis of this distance Ri (step D),estimating the total energy Ei of the event is estimated on the basis of the temporal shape of the signature and of the intensity Ii (step F), classifying the event i as a function of its duration δti, its temperature Ti, its intensity Ii and its energy Ei,estimating the effectiveness range Pi of the event i on the basis of its classification,comparing the effectiveness range Pi with the distance Ri,
if the distance Ri is less than the effectiveness range Pi, then if possible triggering a suitable retaliation in real time, the previous steps are repeated for another pixel of the SWIR images. |
