Method and device for automatically detecting explosive substances in luggage by using multi-view X rays

Abstract

The invention discloses a method for automatically detecting explosive substances in luggage by using multi-view X rays, which comprises the following steps: firstly, acquiring image signals of detected luggage object from various views; secondly, subjecting the image signals from various views to material automatic detection, namely, dividing dual-energy X ray images, performing the material feature recognition of the high and low energy images obtained after division according to a dual-energy X ray material discrimination theory, obtaining dangerous regions in accordance with the material features of the explosive substances, and making positions proper for participating in density calculation; thirdly, subjecting the result of the division of the dangerous regions to density automatic detection, namely, matching the dangerous regions according to matching rules, finding out all dangerous regions of the same object, and obtaining the value of the density of the dangerous regions by using multi-view reconstruction calculation; and finally, according to the results of the material automatic detection and the density detection, determining whether or not to give an alarm for the luggage object. The method has the advantages of quick detection, easy feature matching, high detection precision and high detection efficiency.

Description

technical field [0001] The invention relates to a safety inspection method and device, in particular to a method and device for detecting explosives in luggage by using X-ray digital imaging technology. Background technique [0002] For baggage security inspection, X-ray security inspection technology is currently the most widely used type of non-contact security inspection technology. In recent years, X-ray security inspection technology has developed rapidly driven by aviation security and other needs. [0003] Most of the X-ray inspection equipment used in the early days used single-view single-energy X-ray technology, which can display and represent the projection map of the absorption of rays by different types of substances in different positions in luggage, and then observe the projection map by security inspectors The shape characteristics of each area to determine whether there may be known contraband. [0004] With the continuous development of X-ray technology, a...

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Problems solved by technology

[0007] For the multi-view X-ray inspection technology, it has been applied in medical and industrial inspections, but the channel-type multi-view X-ray fast baggage security inspection technology using this multi-view X-ray scanning technology is only after 2000. In the field of baggage security inspection technology, VIVID Corporation of the United States is the first manufacturer to develop multi-view X-ray automatic detection equipment for explosives (MVT). In general, it extracts the two-dimensional geometric features of the object directly from the projection of each viewing angle and matches the three-dimensional geometric features. After determining the three-dimensional geometric features of the object, it performs density detection and material detection (calculation of the effective atomic number). The disadvantage is that the extraction and matching of 3D geometric features is difficult, and many objects that meet the matching conditions of 3D geometric features need to be checked one by one. In the multi-view layout, the MVT uses two bottom-view perspectives and one horizontal perspective. Although The correlation of each angle of view in the channel is small, which is beneficial to the three-dimensional reconstruction of the inspected object, but this multi-view layout is likely to cause serious overlap of items in horizontally placed luggage, so the features of the inspected object are extracted in the projection images of each angle difficulty

[0008] Although the multi-view X-ray automatic detection equipment EDtS of German Heimann Company adopts the five-view working mode of 3 sources and 5 probes, and adopts 2 bottom radiation sources and 1 top radiation source in the multi-view layout, each bottom The radiation source corresponds to two sets of detectors, and the top radiation source corresponds to one set of detectors to form 5 angles of view. Compared with the MVT of VIVID company in the United States, its multi-angle layout will not cause serious overlap of horizontally placed luggage items. , and the method of 3D reconstruction through projection images from 5 viewing angles has large reconstruction redundancy and low ambiguity, but the working mode of 5 viewing angles easily leads to difficulty in feature matching in the detection process

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