How to recognize for small video sequence with a large sequence? I'm working on the idea of recognizing a small video sequence (a sequence of 18 seconds) within a long one (a sequence of 15 minutes), the first idea that come to mind stats that I have to characterize this small video with some kind of identification. so I will use the identification to look this small sequence inside the long sequence, I'm asking this question to the community, to share with me an approach that can help me in characterize this small video, then recognize it within the long sequence.

thanks.
The most intuitive approach here would simply be taking every pixel's color values, and finding peaks in the individual pixels' reference video/short video cross correlation function. That's basically a W×H-dimensional crosscorrelation function; you could speed that up by doing fast convolution.

You could algorithmically reduce the effort by first reducing the dimensionality of your problem, for example by reducing each video frame to a global brightness value and a mean motion vector of e.g. the frame center region – then you'd only have to calculate a threedimensional crosscorellation function.