Data fusion is a powerful tool to process tremendous remote sensing data for its capability to combine useful information of multisource or multitemporal data

and eliminate their redundancy

so it has been applied on many areas extensively

especially

on remote sensing image processing. At first

this paper simply reviews the necessity of data fusion's appearance and development

together with several definitions brought forward by several investigators. Afterwards

this paper not only attempts to analyze the Data Fusion Engine framework and configuration comprising of pixels-level?feature-level and decision-level fusions detailedly

but also principally analyze the fusion methods and their applications of each data fusion level. In addition

because of close relation between data fusion and image classification

object detection

change detection

and target recognition

these data fusion based applications are also analyzed briefly. Finally

summary and prospect are described.