how many team members?

First of all, Vashini, you don't need to develop complete project, any project and especially GP. there is something called "Further Work" it's the work to be done after your submission, almost of us develop 80% of the project, how to determine that, just select any idea, try to design it, from your design (Logic design) you'll estimate the time need. plus your experience in the tool used and the programming language in supporting for such logic need i.e MATLAB better than C# in huge math. calculations or C# better than VC++ in ADO application.
and if you use .net for example and you have a lot of components you can use the appropriate language for each component and integrate between them later anyway that's not our issue, what I want to say it select good idea for 7 months DON'T select idea could be done in 3 months (that's would be negative!!).
OCR, is very good and you can use it say in traffic monitoring, get the car plate number and car model that exists specific speed another application you can use OCR, you can develop automatic garage, once a car get it, you count the time it was in, calculate the fees before getting out you enforce the driver to pay the fees, OCR is very large and very fantastic, use it but try to search in the business side.
Hope to you the best
sorry for long reply

"I had the idea of doin plate number recognition system for my project but then i dropped it coz my supervisor was not happy abt it"
my advice is to give him good proposal, which contains good abstract about your Idea, your customers (which people make use of it -virtually-) and your passion to make him/her live the idea with you and give you the support.

For your "automated image recognition" idea give me scenario? How the user will use it?

I'll think but give me your interested fields (Software Engineering, Image Proccessing, AI, ....)
you don't need to be sorry man, just ask