Bug 527325 - feConvoleMatrix does not process bias correctly. r=roc

content/svg/content/src/nsSVGFilters.cpp

@@ -4084,7 +4084,7 @@ ConvolvePixel(const PRUint8 *aSourceData,
   }
   for (PRInt32 i = 0; i < channels; i++) {
     aTargetData[aY * aStride + 4 * aX + offsets[i]] =
-      BoundInterval(static_cast<PRInt32>(sum[i] / aDivisor + aBias * 255), 256);
+      BoundInterval(static_cast<PRInt32>(sum[i] / aDivisor + aBias), 256);
   }
   if (aPreserveAlpha) {
     aTargetData[aY * aStride + 4 * aX + GFX_ARGB32_OFFSET_A] =

layout/reftests/svg/filters/feConvolveMatrix-bias-01-ref.svg

@@ -0,0 +1,9 @@
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/licenses/publicdomain/
+-->
+<svg xmlns="http://www.w3.org/2000/svg">
+  <title>Reference for feConvolveMatrix with bias</title>
+  <!-- From https://bugzilla.mozilla.org/show_bug.cgi?id=527325 -->
+  <rect x="0" y="0" width="100" height="100" fill="rgb(187,255,187)"/>
+</svg>

layout/reftests/svg/filters/feConvolveMatrix-bias-01.svg

@@ -0,0 +1,14 @@
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/licenses/publicdomain/
+-->
+<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
+  <title>Testcase for feConvolveMatrix with bias</title>
+  <!-- From https://bugzilla.mozilla.org/show_bug.cgi?id=527325 -->
+  <defs>
+    <filter id="filter" filterUnits="objectBoundingBox" x="0%" y="0%" width="100%" height="100%">
+      <feConvolveMatrix kernelMatrix="1 1 1 1 1 1 1 1 1" bias="0.5"/>
+    </filter>
+  </defs>
+  <rect x="0" y="0" width="100" height="100" fill="rgb(0,255,0)" filter="url(#filter)"/>
+</svg>

layout/reftests/svg/filters/reftest.list

@@ -68,6 +68,7 @@ fails == filter-marked-line-01.svg pass.svg # bug 477704
 == filter-patterned-rect-02.svg pass.svg
 
 == feComposite-arguments-01.svg pass.svg
+== feConvolveMatrix-bias-01.svg feConvolveMatrix-bias-01-ref.svg
 == feConvolveMatrix-order-01.svg feConvolveMatrix-order-01-ref.svg
 
 == feMorphology-radius-negative-01.svg pass.svg