将二维2D数组转换为BufferedImage

Question

我有一个二维的双打数组,它是图像的滤波值.我想将这个数组转换回来BufferedImage.怎么可能投到double[][]一个BufferedImage？

BufferedImage b = new BufferedImage(arr.length, arr[0].length, 3); 
    Graphics c = b.getGraphics();


    PrintWriter writer = new PrintWriter("the-file-name.txt", "UTF-8");
    for(int i=0; i< arr.length; i++){
        for (int j=0; j<arr[0].length; j++){
             c.drawString(String.valueOf(arr[i][j]), i, j);
            writer.print(arr[i][j]+" \t");
        }
        writer.println();
    }

    ImageIO.write(b, "jpg", new File("CustomImage.jpg"));
    System.out.println("end");

当我使用imshow绘制matlab中的file-name.txt时,我可以看到我的过滤后的图像.但是CustomImage.jpg只包含一种颜色.知道为什么吗？

结果是c.drawString(String.valueOf(arr [i] [j]),i,j):

c.drawString(String.valueOf(arr [i] [j]),0 +(i*10),0 +(j*10)):

Matlab plor双倍的arr首先是数组的两倍,第二个是初始的灰度缩放图像:

Answer 1

你的守则

BufferedImage b = new BufferedImage(arr.length, arr[0].length, 3); 
Graphics c = b.getGraphics();

for(int i = 0; i<arr.length; i++) {
    for(int j = 0; j<arr[0].length; j++) {
        c.drawString(String.valueOf(arr[i][j]), 0+(i*10), 0+(i*10));
    }
}
ImageIO.write(b, "Doublearray", new File("Doublearray.jpg"));
System.out.println("end");

重构后

int xLenght = arr.length;
int yLength = arr[0].length;
BufferedImage b = new BufferedImage(xLenght, yLength, 3);

for(int x = 0; x < xLenght; x++) {
    for(int y = 0; y < yLength; y++) {
        int rgb = (int)arr[x][y]<<16 | (int)arr[x][y] << 8 | (int)arr[x][y]
        b.setRGB(x, y, rgb);
    }
}
ImageIO.write(b, "Doublearray", new File("Doublearray.jpg"));
System.out.println("end");