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javaopencvimage-processingpixel

Java Pixel Access OpenCv 2.4.8

I'm trying to Calculate the absolute difference in each CV_8UC3 colour channel, multiplied by the scale in Java using OpenCV 2.4.8!

I know that java doesn't use uchar and thought the closest in java was a String[]

But that didn't work, so I used a short then I got:

"error: cannot find symbol
short[] ptr_entry = image_entry.<short>ptr(row);
symbol:   method <short>ptr(int) location: variable image_entry of type Mat

I tried the possibility trying to use the at method, but I couldn't get this to work in java!

    for (int row = 0; row < image_entry.rows(); ++row)
    {
        short[] ptr_entry = image_entry.<short>ptr(row);
        uchar[] ptr_compressed = image_compressed.<uchar>ptr(row);
        uchar[] ptr_output = image_output.<uchar>ptr(row);

        for (int col = 0; col < image_entry.cols(); col++)
        {
            // Calculation of the absolute difference in each color channel, multiplied by the scale
            ptr_output[0] = Math.abs(ptr_entry[0] - ptr_compressed[0]) * scale;
            ptr_output[1] = Math.abs(ptr_entry[1] - ptr_compressed[1]) * scale;
            ptr_output[2] = Math.abs(ptr_entry[2] - ptr_compressed[2]) * scale;

            ptr_entry += 3;
            ptr_compressed += 3;
            ptr_output += 3;
        }
    }

Any Suggestions?

Solution

  • Use the Mat.get() function to access pixel data.

    public int get(int row,int col, short[] data)

    Read the OpenCV Java API documentation, it would prevent unnecessary posts here.