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BufferedImage to ServletOutputStream: Black Box

Greg Donahue

Joined: Oct 07, 2003
Posts: 24

I'm writing a servlet that accepts the following params thru the URL:

1) a filename for an image sitting on my server, and
2) a pair of X and Y dimensions.

The servlet is supposed to scale the image appropriately and send the result to the response OutputStream. My strategy is: take the image file, load it into a BufferedImage, modify it appropriately, and send it from there to an OutputStream. Here's the code that is supposed to accomplish this:

...that makes sense, right? Currently, getImageFileName() returns the name of a JPEG which I know is valid, and alterImage() does nothing. But here's the thing: when I run this, the image produced is a big black box, and not the expected image at all, and the box has the same dimensions as the expected image.

What am I doing wrong?

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Greg Donahue

Joined: Oct 07, 2003
Posts: 24
Aha. You have to *display* the image first.

...right after the BufferedImage initialization. Kind of makes sense, and then it kind of doesn't, since you aren't really displaying the image anywhere...
I agree. Here's the link:
subject: BufferedImage to ServletOutputStream: Black Box