OpenCV - GrabCut with custom foreground/background models

Question

I want to use the GrabCut algorithm implemented on OpenCV.

As shown in the documentation this is the function signature:

void grabCut(
    InputArra         


        

Answer 1

Even I had a similar problem. This is how I solved it. I edited the GC_EVAL condition in the grabcut source code to this -

if( mode == GC_EVAL )
   { checkMask( img, mask );
    for( int i = 0; i < iterCount; i++ )
{
    GCGraph graph;
    assignGMMsComponents( img, mask, bgdGMM, fgdGMM, compIdxs );

    constructGCGraph(img, mask, bgdGMM, fgdGMM, lambda, leftW, upleftW, upW, uprightW, graph );
    estimateSegmentation( graph, mask );
    return;    
}
}

Notice that the function learnGMMs is not called here. This is done because the Foreground and Background GMMs are precomputed.

You can save models in a .xml file using the following code snippet.

 FileStorage fs("mymodels.xml", FileStorage::WRITE);
        fs << "BgdModel" << bgdModel;
        fs << "FgdModel" << fgdModel;
fs.release();

You can retrieve the models using the following code.

FileStorage fs1("mymodels.xml", FileStorage::READ);

        fs1["BgdModel"] >> bgdModel1;

        fs1["FgdModel"] >> fgdModel1;

This worked for me.