Change Detection Remote Sensing
Remote sensing provides us tool for advanced ecosystem and socio economic management. The collection of remotely sensed data facilitates synoptic analyses of Earth- System function patterning, change detection as local, regional, and global scales over time.
Change Detection Techniques includes- a) Pre-Classification Method, b) Post Classification Method. Pre-Classification method analyses the change without classifying the image value. The most common and widely used pre-classification method is “Vegetation Index Differencing (NDVI)”. Various index has developed after NDVI e.g. NDWI, MNDWI, Change Vector Analysis (CVA) etc.
On the other hand, post Classification method is the most widely used change detection method of modern times. Post classification evaluates the change in land cover based on a detail categorized classification of land cover. Post Classification comparison, Aerial Difference calculation, Image Differencing, Image rationing, Image regression etc. are some of the common post classification Change detection approaches.
https://en.wikipedia.org/wiki/Change_detection_(GIS)
