Comparison study on NDII and NDVI based on rice extraction from rice and ginkgo mixed area

Traditional methods always use NDVI to extract rice from remote sensing images, for example TM. However, little research focusses on introducing a moisture index into rice extraction. This paper introduced NDII and NDVI respectively to extract rice based on a TM image of a rice and ginkgo mixed area, and compared their ability in distinguishing rice and ginkgo from two aspects: position accuracy and regional accuracy. Research results show that: (1) NDII has the higher ability to distinguish rice and ginkgo; (2) rice extraction results from NDII are both better than results from NDVI, whether position accuracy or whole accuracy.