Study On The Morphology And Characteristics Detection Of Bloodstains Based On Hyperspectral Imaging Technology

Morphological detection and age analysis of the bloodstain has always been one of theimportant factors in criminal scene. Through effective means for processing the crime scenebloodstain, we can get a great deal of potential evidences about the crime scene, especially in thepotential crime scene. The traditional blood detection widely used direct view method andreagent method, these methods have great limitations in the crime scene, and it is easy to damagethe blood ingredient itself, also it is not conducive to the forensics and detection of the case.With the development of hyperspectral imaging technology, it has been applied to manyfields such as remote sensing, medicine imaging of tongue, bacteria detection of pork. Aiming atthe crime scene bloodstain detection, especially the potential crime scene bloodstain detection,morphological feature detection which uses hyperspectral imaging technique is presented in thispaper. By this method we can effectively detect and analysis the bloodstain, also make up for agap of hyperspectral imaging technology at the crime scene bloodstain analysis applications. Sothe research of bloodstain pattern feature detection system based on hyperspectral imagingtechnology has a wide application prospect and research space.The main research content as follows:(1) A new bloodstain morphological feature detection method based on hyperspectralimaging technology was proposed. In the actual operation of the experiment, we built ahyperspectral imaging system. By hyperspectral imaging technology, hyperspectral images ofblood fingerprints, blood handwriting, common blood and potential blood in differentwavelengths were got. The spectral information of two-dimensional images and one-dimensionalhyperspectrum together constituted the three-dimensional data cube. Detection and analysis ofbloodstains was made in complex state and complex environment.(2) A hyperspectral image fusion method based on the wavelet transform was applied to thedetection of bloodstain morphological characteristics. Hyperspectral images of differentwavelengths were got by hyperspectral cameras, and these images would exhibit a extremeamplification in certain aspects of bloodstain. Based on the fusion of different wavelengths,extreme amplification characteristic was clustered together to finish the graph reconstruction ofbloodstain, the restructured image was more realistic to reflect bloodstains’ own morphologicalcharacteristics. Therefore, the blood analysis system design based on the hypespectral imagefusion technology is more realistic to reflect bloodstains’ own morphological characteristics, andimproved the recognition accuracy of bloodstain.(3) A new bloodstain age detection method was proposed based on the spectral analysis technology. Bloodstains’ spectral information on different ages and different objects (glass,white writing paper and plastic film) were obtained through fiber optic spectrometer experimentplatform.(4) Base on spectroscopy, an experiment was designed to explore the relationship betweenpostmortem interval and the bloodstain absorption in different time and different objects. Thestudy found a positive correlation between bloodstain age and the absorption as time goes on.