To　deeply　understand　dynamic　evolutional　mechanism　of　initial　of　aeolian　sand　particles　by　multiple　factors,　it　is　very　critical　to　measure　precisely　liftoff　velocities　and　trajectories　of　sand　particles　with　different　movement　types.　Although　the　high-speed　photography　illuminated　by　intensive　and　continuous　laser　is　an　effective　method　for　obtaining　the　above　information,　the　kinds　of　high-　speed　photography　images　cannot　be　processed　precisely　by　overlapping　image　method　due　to　very　low　contrast　ratio　of　objectives　to　backgrounds　and　significant　discrepancy　between　two　frame　images.　As　a　result,　a　new　arithmetic　method　of　image　segmentation　is　proposed　on　basis　of　a　principle　of　variation　in　gray　level　difference　between　two　frame　consecutive　images.　The　cases　show　that　the　new　arithmetic　method　can　segment　successfully　saltating　particles　from　immobile　bed　by　selecting　appropriate　threshold　value　of　gray　level　difference　between　two　continuous　images　and　by　adopting　adaptive　binary　method.　The　new　arithmetic　method　plus　a　minimum　distance　matching　method　of　particles　tracking　velocimetry　(PTV)　can　retrieve　precisely　sand　particles　trajectories　near　the　bed　as　sand　particles　concentration　is　low.