OpenCV: How to copy CvSeq data into CvMat?

Posted by Can Bal on Stack Overflow See other posts from Stack Overflow or by Can Bal
Published on 2010-03-09T01:09:29Z Indexed on 2010/03/09 4:51 UTC
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I have a CvSeq structure at hand, which is the output of an available OpenCV function. This holds 128 bytes of data in each of the sequence elements. I want to copy each of these 128-byte elements into rows of a CvMat structure to form a N-by-128 of type CV_32FC1. What would be the most efficient way to do this?

I thought of using memcpy but I couldn't come up with a working solution.

For the details, I want to calculate the SURF features in an image by cvExtractSURF() function, and copy the SURF descriptors into a matrix for passing it to the cvKMeans2().

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