document: Adaptive image enhancement for retinal blood vessel segmentation Retinal blood vessel images are enhanced by removing the nonstationary background , which is adaptively estimated based on local neighbourhood information . The result is a much better segmentation of the blood vessels with a simple algorithm and without the need to obtain a priori illumination knowledge of the imaging system
doc_bio_tags: B I I O O O O O B I I I O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O
extractive_keyphrases: adaptive image enhancement retinal blood vessel images local neighbourhood information
abstractive_keyphrases: nonstationary background removal image segmentation personal identification security applications