Java 2D Image resize ignoring bicubic/bilinear interpolation rendering hints (OS X + linux)

Question

I'm trying to create thumbnails for uploaded images in a JRuby/Rails app using the Image Voodoo plugin - the problem is the resized thumbnails look like... ass.

It seems that the code to generate the thumbnails is absolutely doing everything correctly to set the interpolation rendering hint to "bicubic", but it isn't honoring them on our dev environment (OS X), or on the production web server (Linux).

I've extracted out the code to generate the thumbnails, rewritten it as a straight Java app (ie kicked off from a main() method) with the interpolation rendering hint explicitly set to "bicubic", and have reproduced the (lack of) bicubic and bilinear resizing.

As expected on both OS X and Linux the thumbanils are ugly and pixelated, but on Windows, it resizes the images nicely with bicubic interpolation used.

Is there any JVM environment setting and/or additional libraries that I'm missing to make it work? I'm doing a lot of banging of head against wall for this one.

Answer 1

maybe is this a solution for you:

public BufferedImage resizeImage(BufferedImage source, int width, int height)
{
     BufferedImage result = new BufferedImage(widht, height, BufferedImage.TYPE_INT_ARGB);
     Graphics g = result.getGraphics();
     g.drawImage(source, 0, 0, widht, height, null);
     g.dispose();
     return result;
}

Answer 2

In the end, upgrading to the latest version of ImageVoodoo seemed to improve quality.

Looking through the source code, it looks like they're doing some funky AWT rendering, and then pulling that out. Nasty, but it seems to work.

Still not as good as ImageMagick, but better than it was.