How to load image to android and resize

Question

I am trying to load an image in a mat and resize it with the below code

        Mat temp1= new Mat();
        int[] train_responses = null;
        Mat temp2 = new Mat();
        Mat temp3 = new Mat();
        Mat train_samples = new Mat();
        for (int ii = 0; ii < 10; ii++){            
            temp1 = Highgui.imread("/mnt/sdcard/images/train/" + ii + ".png");
            Imgproc.resize(temp1, temp2, new Size(30,20));  
        }

but the code crashes with the following log

opencv error assertion failed (ssize.area() > 0) in void cv::resize....

Where am I wrong?

Answer 1

Check that all your png images 0.png, 1.png, ... 9.png all exist, are in the correct location and have non-zero dimensions when you load them via imread. There's nothing otherwise wrong with the code - it works for me when I load my own png image using your code.