I have been working with remote sensing in change detection... attached the link to the methodology translate in english (1) as a referencie to full PDF reserch workin spanish language (2).
1-> https://drive.google.com/file/d/0Bzh6SRELNT5xSTlUUVdoVlVDbjg/edit?usp=sharing
2-> http://eprints.ucm.es/22982/