Created
July 1, 2012 07:15
-
-
Save worthlesscog/3027281 to your computer and use it in GitHub Desktop.
Proportionally scale and smooth
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
/** | |
* @see http://today.java.net/pub/a/today/2007/04/03/perils-of-image-getscaledinstance.html | |
*/ | |
private BufferedImage scale(BufferedImage image, int width, int height, int smoothingSteps) { | |
int w = image.getWidth(); | |
int h = image.getHeight(); | |
int targetH, targetW; | |
if (w > h) { | |
targetW = width; | |
targetH = (int) ((float) h / w * height); | |
} else { | |
targetH = height; | |
targetW = (int) ((float) w / h * width); | |
} | |
BufferedImage i = image; | |
for (int n = 0; (w / 2) >= targetW && (h / 2) >= targetH && n < smoothingSteps; i = draw(i, w, h)) { | |
w /= 2; | |
h /= 2; | |
n++; | |
} | |
return draw(i, targetW, targetH); | |
} | |
private BufferedImage draw(BufferedImage image, int w, int h) { | |
BufferedImage buffer = new BufferedImage(w, h, (image.getTransparency() == Transparency.OPAQUE) ? BufferedImage.TYPE_INT_RGB : BufferedImage.TYPE_INT_ARGB); | |
Graphics2D graphics2d = buffer.createGraphics(); | |
graphics2d.drawImage(image.getScaledInstance(w, h, Image.SCALE_AREA_AVERAGING), 0, 0, null); | |
graphics2d.dispose(); | |
return buffer; | |
} |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment