Alo, Amaral,
following up on you last question on the list, it occurred to me that
you might want to to this (s. below) inside a servlet.
Amaral wrote:
Please, I need help on the following problem. I would like to create a
gif file from a visad display. I am using the code below but it does not
work. Thanks for any help.
Runnable captureImage = new Runnable() {
public void run() {
Image img = display.getImage();
Graphics g =img.getGraphics();
g.drawImage(img, 0,0, null);
try
{
File filee = new File("file.gif");
OutputStream output = new BufferedOutputStream(new FileOutputStream(filee));
GIFEncoder encoder = new GIFEncoder(img);
encoder.Write(output);
}
catch (Exception w){ }
}
}
Thread t = new Thread(captureImage);
t.start();
Two points:
1. I'd recommend you used another image format rather than gif. PNG is
the best alternative for web graphics. JPG is also a choice. (Which
format to use depends on the type of image.)
2. To create an image inside a servlet you can do:
// get the output stream to send the image down the line
ServletOutputStream servOutStream = response.getOutputStream();
// set the content type so the browser will be able to interpret
// the img correctly
response.setContentType( "image/jpeg" );
// this is the image
BufferedImage bufImage = display.getImage(true);
// make a jpg out of it
JPEGEncodeParam jepar = JPEGCodec.getDefaultJPEGEncodeParam(bufImage);
jepar.setQuality( 1.0f, true);
JPEGImageEncoder jpege = JPEGCodec.createJPEGEncoder(servOutStream) ;
jpege.encode(bufImage, jepar);
// and send it to the browser
servOutStream.flush();
servOutStream.close();
You can also save the image to the disk and send a full html page back,
with text and the img.
I'm currently working on a few VisAD servlet examples. These will be
available "soon".
Cheers,
Ugo
