Getting the red, green and blue values of an image Java

Asked Mar 03 '16 at 13:54

Active Mar 03 '16 at 16:05

Viewed 503 times

So this method I wrote gets the mean and standard deviation of an image. I am trying to modify this to get the mean and standard deviation of the red, green and blue values of an image. But I am stumped on how to do to so. I tried to use a colorModel but I was getting nowhere. Could anyone give me some advice on how to modify this code to get the mean and standard deviation of the red, green and blue values?

    public static double redValues(BufferedImage image){
        Raster raster = image.getRaster();
        double mean = meanValue(image);
        double sumOfDiff = 0.0;
        Color c = new Color(image.getRGB(0, 0));
        int red = c.getRed();

         for (int y = 0; y < image.getHeight(); ++y){
               for (int x = 0; x < image.getWidth(); ++x){
                   double r = raster.getSample(x, y, red) - mean;                                  
                               sumOfDiff += Math.pow(r, 2);

                             }                   
                           }
        return sumOfDiff / ((image.getWidth() * image.getHeight()) - 1);
        }

But this still returns a mean brightness value. When I want to get the red value.

edited Mar 03 '16 at 16:05

asked Mar 03 '16 at 13:54

user1167596

What's your problem? Why do you say it doesn't work? – Neil Mar 03 '16 at 14:00
5

http://stackoverflow.com/questions/2615522/java-bufferedimage-getting-red-green-and-blue-individually – andrucz Mar 03 '16 at 14:02
You seem to consider only band 0 of your raster. The getPixel method returns an array for each component. – Xvolks Mar 03 '16 at 14:02
how do I get the getPixel method to return the red value? – user1167596 Mar 03 '16 at 16:05
@Neil my problem is its returning the over all mean of the image and not that of just the red values. – user1167596 Mar 03 '16 at 16:06

Getting the red, green and blue values of an image Java

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