There is a line in ExtractHogFeatures Matlab that I cannot understand

In matlab 2014b, there is a line in the vision dashboard in extractHOGFeatures.m that says

hog = visionExtractHOGFeatures(gMag, gDir, gaussianWeights, params, weights);  

      

        
        
        
      

    

I've searched for visionExtractHOGFeatures everywhere in Matlab, it seems like it's a feature, but I can't find anything about it. extractHOGFeatures.m uses it, it seems important to the algorithm and I want to fully understand the code. What could it be? How can I find what it is?