Runtime error in track()

[pthtruc]

Runtime error in track(), at line cv::calcOpticalFlowPyrLK(im_gray, im_prev, nextPts, pts_back, status_back, err_back);

happened at frame_0002 (attached); tracker is initialized with frame_0001 and topleft = (49, 114), bottomright = ( 531, 275).

[delmottea]

I got an error with your 2 images, but not at the same position than you (the error happened when all the detected features are in the selected area and no one outside), I committed an update on CMT.cpp and it works with your 2 images on my computer. Can you try again and say me if it works?

Do you call cmt.initialise on the first frame before calling cmt.processFrame?

thanks

[pthtruc]

It works on the two images and some other videos! Yes, I did call cmt.initalise(im, topleft, bottomright) on the first frame.

In my codes, I just add the below since those two are not defined in C/C++. Do you think it makes any difference?

define NAN (INT_MIN)

define isnan(x) ( ((x)==NAN)? 1: 0 )

[delmottea]

INT_MIN may not be the best for define NAN but maybe it works. The best solution is to compile with c++11 that defines NAN I made a new commit with compatibility code that I have found on internet, it should work but maybe it's dependent of the compiler.

[pthtruc]

Thank you, delmottea, for your great work! Quick questions:

• how can we check whether the tracker was intialized? is it (nbInitialKeypoints > 0)?
• should we nbInitialKeypoints = 0; in the CMT() constructor? Minor comment: since you are using OpenCV, can we just simply use CV_PI instead of M_PI?

[delmottea]

I've added nbInitialKeypoints = 0 in the constructor so you can use it to check if it's initialized. and thanks for the CV_PI constant, I didn't thought to use it