OpenCV finding picture (frame) in video

Question

I am trying to create small application in C++ that will return probability value (real number from 0 to 1) for recognizing two pictures in video. My idea is to find commercials in certain video material. I was thinking to cut first frame from commercial as well as the last one. In that way I could create app, using OpenCV, that will load a video (TV content) and then it will search for the first frame catted from commercials. If it finds it (with probability more than SOME_PARAMETER) than app can conclude that that commercials starts there. Then I would like to search for the last frame and if it's found (again with probability more than SOME_PARAMETER) than the app can conclude that wanted commercial really exists in given video. This is just an idea. I am expert in C++ but totally newbie with OpenCV. If someone can point me out, or give an example it would be much appreciated. Of course I am open to any suggestions regarding idea. Thanks,

M.

Answer 1

What you are looking for is known as template matching in OpenCV.

To get acquainted with OpenCV you should start reading some tutorials , besides the books there are some good ones on the web. As a C++ guy, you will probably use the C++ interface of OpenCV which uses cv::Mat as the main data structure to represent images. If you see the IplImage data type being used, know it's from the C interface.

After the preliminaries, you will eventually need to learn how to read frames from a video:

• Reading a video with openCV
• Read/write avi video using openCV

and then how to process those frames, individually:

• OpenCV every frame processing (C interface)
• How to find object on video using OpenCV
• Object traking within a video file
• Very Slow Processing of my Opencv Application

Finally, you will investigate how template matching works:

• How can I perform Template Matching process in SUB-IMAGE extracted from ORIGINAL-IMAGE and Display the results in Original Image
• How to handle template matching with multiple occurences

There are other ways to track objects besides template matching, check these references:

• Comparison of OpenCV's feature detection algorithms
• Object Tracking using OpenCV (C++/Python)