OpenCV several objects CvANN_MLP

edit

what is your 'strange result' ?

In code: FileStorage fs( path_to_save_train( module_path, num ), cv::FileStorage::WRITE ); mlp.write( *fs, "mlp" ); I save network state in file, and the result of training is different.

you expect us to debug your github repo ?

I expect to hear something that is not in the documentation. Something like this answer: http://answers.opencv.org/question/25965/opencv-neural-networks/

I made a very simple example:

Mat first_size( 1, 2, CV_32SC1 );
first_size.at< int >( 0 ) = data_width * data_height;
first_size.at< int >( 1 ) = 12;

{
    CvANN_MLP mlp1( first_size );
    const int rrr = mlp1.train( input, output, weights );
    FileStorage fs( "C:\\imgs\\t0.yml", cv::FileStorage::WRITE);
    mlp1.write(*fs, "mlp");
}
{
    CvANN_MLP mlp2( first_size );
    const int rrr = mlp2.train( input, output, weights );
    FileStorage fs( "C:\\imgs\\t1.yml", cv::FileStorage::WRITE);
    mlp2.write(*fs, "mlp");
}

weights in t1.yml t2.yml are different!!!! Why?

I found the reason. same post: https://code.ros.org/trac/opencv/ticket/1411 Reason difference in random generator.

the rng used is the global cv::theRNG()

you could try to seed it to the same val in each run

I harcode everywhere:

theRNG().state = 0x111111; CvANN_MLP mlp( ... ); mlp.train( input, output, weights );

and OK.