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Fixed a bug concenring severe slow downs when filtering BufferedImages with strange ColorModels

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lehni 2004-06-17 14:16:06 +00:00
parent a788892f3e
commit 8c7513a056
1 changed files with 21 additions and 5 deletions
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26
src/helma/image/ImageFilterOp.java
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@ -19,7 +19,7 @@
* It wraps an ImageFilter in a BufferedImageOp * It wraps an ImageFilter in a BufferedImageOp
* Optimizations have been added, like the ignoring of color models * Optimizations have been added, like the ignoring of color models
* and the assumption of INT_RGB type for destination buffers in * and the assumption of INT_RGB type for destination buffers in
* order to speed things up by almost a factor of 2. * order to speed things up by almost a factor of 4.
*/ */
package helma.image; package helma.image;
@ -75,13 +75,25 @@ public class ImageFilterOp implements BufferedImageOp {
// allways work in integer mode. this is more effective, and most // allways work in integer mode. this is more effective, and most
// filters convert to integer internally anyhow // filters convert to integer internally anyhow
cm = new SimpleColorModel(); cm = new SimpleColorModel();
int pixels[] = new int[width];
// create a BufferedImage of only 1 pixel height for fetching the rows of the image in the correct format
// This speeds up things by more than factor 2, compared with the standard BufferedImage.getRGB solution,
// which is supposed to be fast too. This is probably the case because drawing to BufferedImages is
// very optimized or even hardware accelerated.
BufferedImage row = new BufferedImage(width, 1, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = row.createGraphics();
int pixels[] = ((DataBufferInt)row.getRaster().getDataBuffer()).getData();
// calculate scanline by scanline in order to safe memory. // calculate scanline by scanline in order to safe memory.
// It also seems to run faster like that // It also seems to run faster like that
long t = System.currentTimeMillis();
for (int y = 0; y < height; y++) { for (int y = 0; y < height; y++) {
src.getRGB(0, y, width, 1, pixels, 0, width); g2d.drawImage(src, null, 0, -y);
// now pixels contain the rgb values of the row y!
fltr.setPixels(0, y, width, 1, cm, pixels, 0, width); fltr.setPixels(0, y, width, 1, cm, pixels, 0, width);
} }
g2d.dispose();
System.out.println(System.currentTimeMillis() - t);
return consumer.getImage(); return consumer.getImage();
} }
@ -202,7 +214,9 @@ public class ImageFilterOp implements BufferedImageOp {
w = width - x; w = width - x;
if (y + h > height) if (y + h > height)
h = height - y; h = height - y;
image.setRGB(x, y, w, h, pixels, off, scansize);
if (w > 0 && h > 0)
image.setRGB(x, y, w, h, pixels, off, scansize);
} }
} }
@ -212,7 +226,9 @@ public class ImageFilterOp implements BufferedImageOp {
w = width - x; w = width - x;
if (y + h > height) if (y + h > height)
h = height - y; h = height - y;
image.getRaster().setDataElements(x, y, w, h, pixels);
if (w > 0 && h > 0)
image.getRaster().setDataElements(x, y, w, h, pixels);
} }
} }