China will,as a component of‘Digital Earth,’establish a Geomatics Informatization Technology System(GITS)which is characterized by real-time acquisition,automatic processing,networking service,and socialized application with fundamental geographical information.The basic composition of GITS is proposed.GITS covers four layers and six platforms.The four layers are data acquisition,processing,management,and application and services.The six platforms are informatic geodetic datum,high-precision geo-spatial data acquisition,automatic geo-spatial data processing,grid-based geo-spatial information management,comprehensive geo-spatial information sharing and service,and geo-spatial information integration and application.The informatic geodetic datum platform provides a carrier for all the four layers and a base for the other five platforms.The high-precision geo-spatial data acquisition platform belongs to the acquisition layer.The automatic geo-spatial data processing platform belongs to the processing layer.The grid-based geo-spatial information management platform belongs to the management layer and is a bridge connecting geospatial data acquisition and spatial information sharing service and integrated applications.The comprehensive geo-spatial information sharing and service platform belongs to the application and service layer.Finally,this paper presents thoughts for constructing GITS.
Object-based change detection has been the hotspot in remote sensing image processing.A new approach toward object-based change detection is proposed.The two different temporal images are unitedly segmented using the mean shift procedure to obtain corresponding objects.Then change detection is implemented based on the integration of corresponding objects’ intensity and texture differences.Experiments are conducted on both panchromatic images and multispectral images and the results show that the integrated measure is robust with respect to illumination changes and noise.Supplementary color detection is conducted to determine whether the color of the unchanged objects changes or not when dealing with multispectral images.Some verification work is carried out to show the accuracy of the proposed approach.
ZHANG Guo1,2,LI Yang1 & LI ZhiJiang3 1 State Key Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University,Wuhan 430079,China
