Problem with colours when writing BufferedImage to file

Newbie & Debugging Questions
#1

I have made a little Java snippet to load some image files, combine them together into a single image, and write them to file. Now, when I display the BufferedImage that is internal to my application, it looks fine, very nice primary colours. But when I write to file and inspect the resulting jpg, I get a fairly weird set of colours. Does anyone know what the problem might be? Perhaps I need to specify what colour model I am using, to the ImageWriter object? I’m using the ImageIO.write(BufferedImage, String, OutputStream) method.

(Incidentally, has anyone else noticed how easy it is to miss the ‘f’ key and write BuggeredImage instead?)

#2

maybe something is wrong with ur outputstream?

#3

Well, this might not be very helpful, but I have this too. Writing in PNG format is ok, but in JPG the colors get an orange/pink shade over them. I just write RGB or ARGB BufferedImages, so I that is a pretty standard case.

#4

Well some image quiality loss in jpg is to be excepected as its lossy compression so u dont get pixel perfect reproduction.

#5

Eh… I didn’t think that a pink/orange pic was considered quality-loss.

Have you actually read the thread?

#6

More information : I tried making a png (which indeed works) for comparison. Then I uploaded the png and jpg versions to Photobucket so people could see what the problem was. However, my browser refuses to display the jpeg version; I just get the little red cross. I find this exceedingly weird, since my windows Picture Viewer does display it, even if it is in weird colours.

#7

The problem is with the image type of your bufferedimage, the ImageIO JPEG compressor needs a BufferedImage.TYPE_INT_RGB image. When you provide a BufferedImage.TYPE_INT_ABGR or BufferedImage.TYPE_INT_ARGB you will get the weird results you are seeing now. If you need to use ABGR or ARGB in your program, just create a new RGB bufferedimage and Graphics.drawImage() the ARGB/ABGR image on that and write the RGB image away.

#8

Doh ;D :-[

There is no point in having A in a JPG anyway… Thanks.

Still a bit weird that ImageIO doesn’t take care of this automagicly.

#9

Ah, that was it. Thanks. Oddly enough, though, I manage to run out of heap space when drawing to the Graphics object. Never seen that in a program without bugs. I had to scale my image by 0.5 before it would fit in memory. :-\

#10

In case you don’t know yet, enlarge the maximum heap-space with -mx128M as vm-argument.