Help to learn Image Search algorithm

I am a beginner in image processing. I want to write an application in C++ or in C# for

1. Searching an image in a list of images
2. Search开发者_C百科ing for a particular feature (for e.g. face) in a list of images.

Can anybody suggest where should I start from? What all should I learn before doing this? Where can I find the correct information regarding this?

In terms of the second one, you should start off with learning how to solve the decision problem of whether a square patch contains a face (or whatever kind of object you are interested in). For that, I suggest you study a little bit of machine learning, the AdaBoost algorithm, Haar features, and Viola-Jones.

Once you know how to do that, the trick is really just to take a sliding window across your image, feeding the contents of that window into your detector. Then you shrink your main input image and repeat the process until your input image has gotten smaller than the minimum size input for your detector. There are, of course, several clever ways to parallelize the computation and speed it up, but the binary detector is really the interesting part of the process.

You may find some of the material linked from the CSE 517: Machine Learning - Syllabus helpful in getting into machine learning and understanding AdaBoost. You will certainly find the Viola-Jones paper of interest.