刑事技术
刑事技術
형사기술
FORENSIC SCIENCE AND TECHNOLOGY
2015年
3期
215-217
,共3页
血指印%光谱成像%光滑纸张%复杂背景干扰%配光角度
血指印%光譜成像%光滑紙張%複雜揹景榦擾%配光角度
혈지인%광보성상%광활지장%복잡배경간우%배광각도
blood ifngerprints%spectral imaging%glossy paper%complex background interference%light illumination angle
目的：研究光谱成像和传统光学方法增强光滑纸张上（有复杂背景干扰的）血指印效果，比较这些方法的实际效果和消除背景的规律性及特点，便于有选择性的拍摄利用。方法利用可见光定向反射（小偏角）配光照明方法照相；利用多光谱成像仪中的420~720 nm波段进行可见光多光谱成像方法照相，并进行影像分类和去混合处理；利用全波段CCD系统进行降温降噪恒温锁定、暗视场配光照明、254 nm短波紫外反射照相，分别对21种光滑纸张上的血指印样本进行拍摄采集。结果得到了21种光滑纸张上的血指印不同程度的显现效果，其中利用可见光定向反射（小偏角）配光照明方法照相、可见光多光谱成像方法照相以及暗视场配光照明、254 nm短波紫外反射照相，消除21种血指印背景干扰后，使影像效果明显改善的分别约占19%、33%和66%。结论利用不同光谱拍摄光滑纸张上（背景干扰状况下）的血指印，能各自消除某些特定背景干扰状况，能使得影像效果得到较好的改善，利用不同光谱拍摄光滑纸张上（背景干扰状况）的血指印具有各自的优缺点，可根据消除各种血指印背景干扰的实际效果来选择相应的光谱拍摄。
目的：研究光譜成像和傳統光學方法增彊光滑紙張上（有複雜揹景榦擾的）血指印效果，比較這些方法的實際效果和消除揹景的規律性及特點，便于有選擇性的拍攝利用。方法利用可見光定嚮反射（小偏角）配光照明方法照相；利用多光譜成像儀中的420~720 nm波段進行可見光多光譜成像方法照相，併進行影像分類和去混閤處理；利用全波段CCD繫統進行降溫降譟恆溫鎖定、暗視場配光照明、254 nm短波紫外反射照相，分彆對21種光滑紙張上的血指印樣本進行拍攝採集。結果得到瞭21種光滑紙張上的血指印不同程度的顯現效果，其中利用可見光定嚮反射（小偏角）配光照明方法照相、可見光多光譜成像方法照相以及暗視場配光照明、254 nm短波紫外反射照相，消除21種血指印揹景榦擾後，使影像效果明顯改善的分彆約佔19%、33%和66%。結論利用不同光譜拍攝光滑紙張上（揹景榦擾狀況下）的血指印，能各自消除某些特定揹景榦擾狀況，能使得影像效果得到較好的改善，利用不同光譜拍攝光滑紙張上（揹景榦擾狀況）的血指印具有各自的優缺點，可根據消除各種血指印揹景榦擾的實際效果來選擇相應的光譜拍攝。
목적：연구광보성상화전통광학방법증강광활지장상（유복잡배경간우적）혈지인효과，비교저사방법적실제효과화소제배경적규률성급특점，편우유선택성적박섭이용。방법이용가견광정향반사（소편각）배광조명방법조상；이용다광보성상의중적420~720 nm파단진행가견광다광보성상방법조상，병진행영상분류화거혼합처리；이용전파단CCD계통진행강온강조항온쇄정、암시장배광조명、254 nm단파자외반사조상，분별대21충광활지장상적혈지인양본진행박섭채집。결과득도료21충광활지장상적혈지인불동정도적현현효과，기중이용가견광정향반사（소편각）배광조명방법조상、가견광다광보성상방법조상이급암시장배광조명、254 nm단파자외반사조상，소제21충혈지인배경간우후，사영상효과명현개선적분별약점19%、33%화66%。결론이용불동광보박섭광활지장상（배경간우상황하）적혈지인，능각자소제모사특정배경간우상황，능사득영상효과득도교호적개선，이용불동광보박섭광활지장상（배경간우상황）적혈지인구유각자적우결점，가근거소제각충혈지인배경간우적실제효과래선택상응적광보박섭。
ABSTRACT:ObjectiveTo compare the effects of spectral imaging and traditional optical methods for blood ifngerprints on glossy paper with complex background and the regularity and characteristics of eliminating background, for the purpose of selection the most optimal photographical method.MethodsThree methods were employed to take photo of blood ifngerprint samples on 21 different kinds of glossy paper separately: the optical directional relfection at small angle with light illumination for photography; the visible spectrum imaging at 420~720 nm band of the Multiple Spectral Imager, classifying images and ifltering the mixed; the full-wave band CCD system for the constant temperature locking by reducing temperature and ifltering noise, illuminating with light in the dark ifeld, and the relfex photography by 254 nm short-wave ultraviolet band.Results Different images of blood ifngerprints on 21 kinds of glossy paper had been taken, among which, the image effects were obviously improved by light illumination method at 19%, Multiple Spectral Imager at 33% and full-wave band CCD system at 66% respectively after eliminating blood fingerprint background interference.ConclusionsDifferent imaging methods by multiple spectra for blood fingerprints on different glossy paper could eliminate the interference under some specific background, and to improve the imaging effects. It is suggested to select the right photographic method by the corresponding spectrum according to the real effect of eliminating interference from the background of the blood ifngerprints.
