Research On Buildings Shadow Detection Method And Height Inversion With High Resolution Sensed Image

In recent years,remote sensing technology develops rapidly.High spatial resolution re mote sensing image is applied widely in dynamic monitoring and data collection owing to pe rceptual intuition,correctness and rapid updating.Shadow exists in high spatial resolution re mote sensing image universally.It is because the radiation energy of sunlight is covered,and the existence of shadow makes the image gray value change locally.It affects the correctness of image interpretation,target extraction and change detection.In addition,shadow is one of basic features of high spatial resolution remote sensing image.It can utilize the shadow to in vert the height and shape of building and acquire the relative position.The experimental data is Quickbird image,in order to enhance the shadow detectio n effect and make the detection result more accurate and effective,an automatic detection me thod of Quickbird image is modified based on the multiband spectrum difference.Accordin g to the multiband feature of Quickbird remote-sensing image and considering spectrum diff erence between shadow and non-shadow at different bands,blue,green and near-infrared ba nd of Quickbird is used for shadow detection,and multiband shadow index is constructed t o enhance shadow information and get the suspected shadow area;Moreover,On the basis of that water index is constructed to increase the difference between water body and other s urface feature and finally get the non-shadow area.Through logical non-operation,the non-s hadow area in the shadow area is eliminated.Combined with the corrosion and expansion an d other image processing of mathematical morphology,better shadow area is got to realize a utomatic detection of building shadows.Geometric relation between the shadow length and height of building is analyzed and th e length of shadow is measured by using the pixel number method so as to calculate the heig ht of building,the height of multiple building with high precision and integration is realized by using C#and AE.