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POTransparent regions of a BufferedImage are writing out black
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copied!<p>I know this is something to do with compositing but I can't work out what. In an earlier section of code, a particular list of pixels in a BufferedImage are set to be transparent black:</p> <pre><code> for(Pixel p : closed){ Color c = new Color(image.getRGB(p.x, p.y)); Color newC = new Color(0,0,0, 0); image.setRGB(p.x, p.y, newC.getRGB() & 0x00000000); } if(andCrop){ image = image.getSubimage(left, top, right-left, bottom-top); } return image; </code></pre> <p>Then I attempt to write the image out:</p> <pre><code>try { BufferedImage out = new BufferedImage(image.getWidth(), image.getHeight(), java.awt.Transparency.TRANSLUCENT); Graphics2D g2d = out.createGraphics(); g2d.setComposite(AlphaComposite.Clear); g2d.fillRect(0, 0, image.getWidth(), image.getHeight()); g2d.setComposite(AlphaComposite.Src); g2d.drawImage(image, 0, 0, image.getWidth(), image.getHeight(), null); g2d.dispose(); File outputfile = new File(file); ImageIO.write(out, "png", outputfile); } catch (IOException e) { } </code></pre> <p>Now, I know that 'out' is clear before I attempt to draw the image onto it. What I'm not getting is what's wrong with my compositing. Instead of coming out as transparent, I'm getting full-black.</p> <p>All bufferedimages used are INT_ARGB.</p> <p>EDIT - This has been solved. The image source was from ImageIO.read and the BufferedImage returned did not support alpha. A quick post-read conversion let the rest of the code run smoothly.</p>

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