如何在 Jframe 上显示 jpeg2000 图像？

Question

我有一个JPEG2000图像， img.jp2上的文件，并在一个DataInputStream对象imgobj在我的项目，并希望显示在JFrame的形象。

这里推荐的老版本jai_imageio-1.1.jar和jj2000库都包含了。

我试过了：

    j2kImageReader.setInput(new FileImageInputStream(new File(fileName)));
            ImageReadParam imageReadParam = 
j2kImageReader.getDefaultReadParam();
imageReadParam.setSourceRegion(new Rectangle(0, 0, 300, 300));
IIOImage image = j2kImageReader.readAll(0, imageReadParam); 

       // This type of images is difficult to handle, 
       // I just don't know what to do with IIOImage, 
       // ImageIcon doesn't accept that type in its constructor.

和这个：

    Image img = ImageIO.read(new File(fileName));
ImageIcon imgIcon = new ImageIcon(img);

JLabel label = new JLabel(imgIcon);
panel1.add(label);
panel1.repaint();

//Error: Can't read input file!. The panel is still empty

JMRTD 中包含的选项使用两个解码器，并且没有一个接受.jp2 ：

NistDecoder dec=new NistDecoder();
WsqDecoder wdec=new WsqDecoder();

//using the last one, I tried: bitmp= wdec.decode(myDataInputStream);
//but with Error, Invalid pointer : 0!.

所以问题是：使用 jj2000 或 jai_imageio 从文件或 DataInputStream 读取 jpeg2000 图像的正确用法是什么，如果可能，将其显示在 JFrame 的简单面板上？

谢谢你的帮助。

编辑

正如评论中所要求的，这就是我所做的：

         //1   
         FaceImageInfo imgfn = fsinf.getFaceImageInfos().get(0);
         BufferedImage bf=ImageIO.read(imgfn.getImageInputStream());

         ImageIcon iconImg = new ImageIcon();             
         iconImg= new ImageIcon(bf);// if this fails try write it to a stream and read it back see //2
         JLabel(iconImg, JLabel.CENTER);


         //2
         ByteArrayOutputStream baos=null;
         try{
             baos=new ByteArrayOutputStream();
             ImageIO.write(bf, "jpg", baos);
         }
         finally{
             try{
                 baos.close();
             }
             catch(Exception ex)
             {
                 ex.printStackTrace();
             }
         }
         try {
             ByteArrayInputStream bais=new ByteArrayInputStream(baos.toByteArray());
             bf2=ImageIO.read(bais) ;
             iconImg= new ImageIcon(bf2);
             JLabel(iconImg, JLabel.CENTER);

        } catch (Exception e) {
            e.printStackTrace();
        }

Answer 1

假设代码以其他方式读取您想要的图像，您可以轻松地从ImageReader获得一个BufferedImage ，如下所示：

try (ImageInputStream input = ImageIO.createImageInputStream(new File(fileName))) {
    j2kImageReader.setInput(input));

    // Not sure why/if you want to read only the upper left, but I'll leave it as is
    ImageReadParam imageReadParam = j2kImageReader.getDefaultReadParam();
    imageReadParam.setSourceRegion(new Rectangle(0, 0, 300, 300)); 

    // Use read instead of readAll
    BufferedImage image = j2kImageReader.read(0, imageReadParam); 

    // You can now create an icon and add to a component
    Icon icon = new ImageIcon(image);
    JLabel label = new JLabel(icon);

    // Etc...
}