等距圆柱投影图像投影（Java）

Question

我需要从我拥有的图像中创建一个等距圆柱投影/变换图像。 等距圆柱的公式为http://sphotos-e.ak.fbcdn.net/hphotos-ak-ash3/525279_4306756439568_1150093099_n.jpg。

我所拥有的代码是使用公式http://sphotos-g.ak.fbcdn.net/hphotos-ak-ash3/72384_4306756599572_459887390_n.jpg的墨卡托投影代码改编的，我不完全理解，因此它会输出错误的图像。

import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;

public class EquidistantCylindrical {

public static void main(String args[]) throws IOException {


BufferedImage hugeImage = ImageIO.read(EquidistantCylindrical.class.getResource("world1.jpg"));
    int[][] rgb = convertTo2DUsingGetRGB(hugeImage);

    double minLat = -75.0;
    double maxLat = 75.0;

    BufferedImage newImage = reprojMerc(hugeImage, minLat, maxLat);

    File outputfile = new File("worldmapprojected.jpg");
    ImageIO.write(newImage, "jpg", outputfile);


}

public static int[][] convertTo2DUsingGetRGB(BufferedImage image) {
    int widthimg = image.getWidth();
    int heightimg = image.getHeight();
    int[][] result = new int[widthimg][heightimg];

    for (int row = heightimg; row > heightimg; row--) {
        for (int col = widthimg; col > widthimg; col--) {
            result[row][col] = image.getRGB(col, row);
        }
    }

    return result;
}

public static BufferedImage reprojMerc(BufferedImage img, double minlat, double maxlat) {
    // Convert the coords into a sensible format.
    minlat *= Math.PI / 180;
    maxlat *= Math.PI / 180;
    double dlat = maxlat - minlat;
    System.out.println(dlat);
    // Convert to cylindrical
    double minmerc = Math.cos(minlat);
    double maxmerc = Math.cos(maxlat);
    double dmerc = maxmerc + minmerc;
    System.out.println(dmerc);

    // Setting dimensions of new image
    int width = img.getWidth();
    int height = img.getHeight();
    int projected_width = (int)(width*dmerc/dlat)*10;
    System.out.println(projected_width);
    int projected_height = height;
    BufferedImage pimg = new BufferedImage(projected_width, projected_height, img.getType());

    // Copy the lines.
    for (int py = 0; py < projected_height; py++) {
        double merc = maxmerc - dmerc * ((double) py) / projected_height;
        double lat = 2 * Math.atan(Math.exp(merc)) - Math.PI / 2;
        int gy = (int) (height * (maxlat - lat) / dlat);

        int[] rgb = img.getRGB(0, gy, width, 1, null, 0, 4 * width);
        pimg.setRGB(0, py, projected_width, 1, rgb, 0, 4 * projected_width);
    }
    return pimg;
}
}

提前谢谢。