Error “Train dataset for temp stage can not be filled.” while using traincascade tool of OpenCV

Question

I\'m building the opencv_traincascade.exe tool from source code (OpenCV 2.4.0) using vs2010 on windows 7. I want to train a LBP classifier, so I\'m using opencv_traincascade

Answer 1

I hope to close this question. For those who stumbled over this as well. I know its old. I debugged the traincascade and found, that at some point the following line:

src = imread( imgFilenames[last++], CV_LOAD_IMAGE_GRAYSCALE );

returns a null mat. This line should read the background images.

This bug occures, if you build traincascade.cpp as debug and are using the release libs and dlls of opencv. (The other way around shouldn't work as well.