Java BufferedImage Operation height(BufferedImage image, Double measurementLatitude, Double measurementLongitude)

Description

This function converts a measurementLatitude, measurementLongitude into a pixel co-ordinate and reads the associated pixel and returns the red value of the pixel - representing height - 0 is low, 255 is high

License

Open Source License

Parameter

Parameter	Description
image	a parameter
measurementLatitude	a parameter
measurementLongitude	a parameter

Return

returns the red value of the read pixel

Declaration

public static double height(BufferedImage image,
        Double measurementLatitude, Double measurementLongitude)

Method Source Code

//package com.java2s;
import java.awt.image.BufferedImage;

public class Main {
    /**//  w  w w.  ja  va2 s. c o  m
     * This function converts a measurementLatitude, measurementLongitude into a pixel co-ordinate and reads the 
     * associated pixel and returns the red value of the pixel - representing height - 0 is low, 255 is high
     * @param image
     * @param measurementLatitude
     * @param measurementLongitude
     * @return returns the red value of the read pixel 
     */
    public static double height(BufferedImage image,
            Double measurementLatitude, Double measurementLongitude) {
        int w = image.getWidth();
        int h = image.getHeight();
        int zeroLat = h / 2;
        int zeroLong = w / 2;
        Double degreeXPerPixel = (double) w / 360;
        Double degreeYPerPixel = (double) h / 180;
        int y = zeroLat
                + ((int) Math.round(measurementLatitude * degreeYPerPixel
                        * -1));
        int x = zeroLong
                + ((int) Math.round(measurementLongitude * degreeXPerPixel));
        int pixel = image.getRGB(x, y);
        return (pixel >> 16) & 255;
    }
}