[SCM] WebKit Debian packaging branch, debian/experimental, updated. upstream/1.3.3-10851-g50815da

[commit-queue at webkit.org]

The following commit has been merged in the debian/experimental branch:
commit 0458085cbfae51f7392c2ffca2de16d8a160843e
Author: commit-queue at webkit.org <commit-queue at webkit.org@268f45cc-cd09-0410-ab3c-d52691b4dbfc>
Date:   Mon Dec 13 09:11:59 2010 +0000

    2010-12-13  Noel Gordon  <noel.gordon at gmail.com>
    
            Reviewed by Eric Seidel.
    
            [chromium] Reduce canvas.toDataURL("image/jpeg") run-time cost by 10%
            https://bugs.webkit.org/show_bug.cgi?id=50804
    
            Follow on from r73173, unroll the SkUnPreMultiply::PMColorToColor() call
            viz., compute the unpremultiplatcion in-place. This reduces the run-time
            cost of jpeg encoding by 10-15% for my image test set.
    
            No new tests: canvas.toDataURL() is covered by existing tests.
    
            * platform/image-encoders/skia/JPEGImageEncoder.cpp:
            (WebCore::preMultipliedBGRAtoRGB):
    
    git-svn-id: http://svn.webkit.org/repository/webkit/trunk@73890 268f45cc-cd09-0410-ab3c-d52691b4dbfc

diff --git a/WebCore/ChangeLog b/WebCore/ChangeLog
index 0fc895d..711b333 100644
--- a/WebCore/ChangeLog
+++ b/WebCore/ChangeLog
@@ -1,3 +1,19 @@
+2010-12-13  Noel Gordon  <noel.gordon at gmail.com>
+
+        Reviewed by Eric Seidel.
+
+        [chromium] Reduce canvas.toDataURL("image/jpeg") run-time cost by 10%
+        https://bugs.webkit.org/show_bug.cgi?id=50804
+
+        Follow on from r73173, unroll the SkUnPreMultiply::PMColorToColor() call
+        viz., compute the unpremultiplatcion in-place. This reduces the run-time
+        cost of jpeg encoding by 10-15% for my image test set.
+
+        No new tests: canvas.toDataURL() is covered by existing tests.
+
+        * platform/image-encoders/skia/JPEGImageEncoder.cpp:
+        (WebCore::preMultipliedBGRAtoRGB):
+
 2010-12-13  Helder Correia  <helder at sencha.com>
 
         Reviewed by Eric Seidel.
diff --git a/WebCore/platform/image-encoders/skia/JPEGImageEncoder.cpp b/WebCore/platform/image-encoders/skia/JPEGImageEncoder.cpp
index c04019d..d4e1481 100644
--- a/WebCore/platform/image-encoders/skia/JPEGImageEncoder.cpp
+++ b/WebCore/platform/image-encoders/skia/JPEGImageEncoder.cpp
@@ -34,6 +34,7 @@
 #include "IntSize.h"
 #include "SkBitmap.h"
 #include "SkUnPreMultiply.h"
+#include "SkColorPriv.h"
 extern "C" {
 #include <stdio.h> // jpeglib.h needs stdio.h FILE
 #include "jpeglib.h"
@@ -82,11 +83,19 @@ static void handleError(j_common_ptr common)
 // be ignored? See bug http://webkit.org/b/40147.
 void preMultipliedBGRAtoRGB(const SkPMColor* input, unsigned int pixels, unsigned char* output)
 {
-    while (pixels-- > 0) {
-        SkColor unmultiplied = SkUnPreMultiply::PMColorToColor(*input++);
-        *output++ = SkColorGetR(unmultiplied);
-        *output++ = SkColorGetG(unmultiplied);
-        *output++ = SkColorGetB(unmultiplied);
+    static const SkUnPreMultiply::Scale* scale = SkUnPreMultiply::GetScaleTable();
+
+    for (; pixels-- > 0; ++input) {
+        const unsigned alpha = SkGetPackedA32(*input);
+        if ((alpha != 0) && (alpha != 255)) {
+            *output++ = SkUnPreMultiply::ApplyScale(scale[alpha], SkGetPackedR32(*input));
+            *output++ = SkUnPreMultiply::ApplyScale(scale[alpha], SkGetPackedG32(*input));
+            *output++ = SkUnPreMultiply::ApplyScale(scale[alpha], SkGetPackedB32(*input));
+        } else {
+            *output++ = SkGetPackedR32(*input);
+            *output++ = SkGetPackedG32(*input);
+            *output++ = SkGetPackedB32(*input);
+        }
     }
 }
 

-- 
WebKit Debian packaging