JAI + JAI Image IO - ImageWrite operation problem: color reversed

Question

I installed jai 1.1.3 and jai imageio 1.1 on jdk 1.6 and did a test with the following code.
     public static void main(String args[]) {
          Byte[] bandValues = new Byte[3];
          bandValues[0] = (byte)255;
          bandValues[1] = (byte)0;
          bandValues[2] = (byte)0;
          ParameterBlock params = new ParameterBlock();
          params.add((float)300).add((float)200);
          params.add(bandValues);
          PlanarImage bim = JAI.create("constant", params);
          JAI.create("imagewrite", bim, "d:/dev/baseImage.png", "PNG");
          JAI.create("filestore", bim, "d:/dev/baseImage2.png", "PNG");
          PlanarImage pi = JAI.create("imageread", "d:/dev/baseImage.png");
          PlanarImage pi2 = JAI.create("imageread", "d:/dev/baseImage2.png");
          JFrame frame = new JFrame();
          frame.setTitle("Output Image");
          Container contentPane = frame.getContentPane();
          contentPane.setLayout(new GridLayout(1,3));
          contentPane.add(new JScrollPane(new DisplayJAI(bim)));
          contentPane.add(new JScrollPane(new DisplayJAI(pi)));
          contentPane.add(new JScrollPane(new DisplayJAI(pi2)));
          frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          frame.setSize(960, 400);
          frame.setVisible(true);
     }I found that the color in the output file created by "imagewrite" was reversed - bim is red but pi is blue.
The one created by "filestore" was correct: pi2 was red.
Did I use the "imagewrite" operation incorrectly? How should I use the imagewrite operation?

Answer 1

I think you are using it correctly and you've encountered a bug. The same thing occurs on my machine. PlanarImage is using an interlaced raster which stores pixels as BGRBGRBGR ect... But the only way I can see this causing a problem is if the imagewrite operation was going directly to the DataBuffer for the pixels. If it retrieved it through the raster the colors should not be switched.
Interestingly enough if I do this
JAI.create("imagewrite", bim.getAsBufferedImage(), "d:/dev/baseImage.png", "PNG");then it works correctly. This suggests even more that the fault is with imagewrite operation interpreting the PlanarImage wrongly.