Get Image's bytes

Question

Hi people,
I'm trying to get the bytes from an image. I know the complete path to that image, and I know the image's name also, so I pass the image's whole name as a String to a method wich will read the bytes. When I try to read the image's bytes I get the following meassures: width = -1, height = 0.
This is the code I use:
  int err = imageReturn(path + "/" + img);
  byte[] b2bytes = b2.toByteArray();
public int imageReturn(String imagePath){
    //path is c:\javi\image.jpg
    try{
        int w,h;
        Image img = null;
        img = Toolkit.getDefaultToolkit().getImage(imagePath);
        w = img.getWidth(null);
        h = img.getHeight(null);
System.out.println("image size: " + w + "x" + h); //--> print's -1x0!!!
        BufferedImage finalImage = new BufferedImage(w, h, 
                                            BufferedImage.TYPE_INT_RGB);
        finalImage.createGraphics().drawImage(img, 0, 0, null);
        b2 = new ByteArrayOutputStream(); //global
        JPEGImageEncoder encoder=JPEGCodec.createJPEGEncoder(b2);
        JPEGEncodeParam param=encoder.getDefaultJPEGEncodeParam
                                                           (finalImage);
        param.setQuality(1.0f, false);
        encoder.setJPEGEncodeParam(param);
        encoder.encode(finalImage);
        b2.close();
        return(0);
    }catch(Exception e){
        System.out.println(e.toString());
        return(-1);
}//imageReturnAs you see, the goal is to get a byte[] with the image information. I don't know if there's any other way (simpler one) to solve it. Any help will be appreciated.
Thanks all,
Javi

Answer 1

The problem really is withe the Image class, which was never intended for this sort of thing. If you use the ImageIO classes, you can get BufferedImages direct from jpg files, and then you have access to the underlying buffers:
import java.io.*;
import javax.imageio.*;
import java.awt.image.*;
public class FileOperations
    public static BufferedImage readImageFromFile(File file) throws IOException
        return ImageIO.read(file);
    public static void writeImageToFile(File file,BufferedImage bufferedImage) throws IOException
        ImageIO.write(bufferedImage,"JPG",file);
}