I am using opencv with android , for that I just try my code first on visual studio with opencv , it works fine on it and then I put it on android, but something is confusing in understanding function and their cause of error like in for example the simple program resize(image,image,image2.size()); image.convertTo(image,CV_32FC4,1.0/255.0); image2.convertTo(image2,CV_32FC4,1.0/255.0); vector channel; split(image,channel); Mat mask = image.clone(); // clone function work fine //Mat mask = channel[3].clone(); // clone function show me error // channel.resize(3); // show error Mat it; multiply(mask,channel[0],channel[0]); multiply(mask,channel[1],channel[1]); multiply(mask,channel[2],channel[2]); merge(channel,it); When I use Mat mask = channel[3].clone(); It show me error of Method 'clone' could not be resolved but when I use Mat mask = image.clone(); it works fine. Why is that ? Same when I use channel.resize(3); it show me error in resize function , error is Invalid arguments 'Candidates are: void resize(?, cv::Mat)'.…