Hi, Matt S Rinc here and I can help you - you need an MPEG-7 like image recognition application (I have graduated using it in 2008).
But I would first like to get more information. Do you require .Net (I don't use/program for it)? Do you require any specific database (suggesting local SQLite or eXist database, whatever is suitable more e.g. eXist is an XML database, both suggestions would use real images saved as paths to files while storing only features and possibly thumbnails of indexed images)? Do you insist on web platform or would desktop cross-platform application be even better? Is OpenCV (free image recognition software library) allowed to use?
After your answers I can provide more details.
Milestones would be two - first for a draft version of an application and the second for the final version (if non-web application would be desired than versions for Windows, Mac and Android would be made).
Best Regards,
Matt