--- a/Depth24Image.st	Thu Dec 18 01:11:55 2008 +0100
+++ b/Depth24Image.st	Mon Dec 22 15:33:07 2008 +0100
@@ -2506,6 +2506,49 @@
 
 !Depth24Image methodsFor:'enumerating'!
 
+colorsAtX:x from:yLow to:yHigh do:aBlock
+    "perform aBlock for each pixel from y1 to y2 in col x.
+     The block is passed the color at each pixel.
+     This method allows slighly faster processing of an
+     image than using atX:y:, since some processing can be
+     avoided when going from pixel to pixel. However, for
+     real image processing, specialized methods should be written."
+
+    |srcIndex "{ Class: SmallInteger }"
+     y1       "{ Class: SmallInteger }"
+     y2       "{ Class: SmallInteger }"
+     rVal     "{ Class: SmallInteger }"
+     gVal     "{ Class: SmallInteger }"
+     bVal     "{ Class: SmallInteger }"
+     lastR lastG lastB lastColor bytes|
+
+    photometric ~~ #rgb ifTrue:[
+        ^ super colorsAtX:x from:yLow to:yHigh do:aBlock.
+    ].
+
+    bytes := self bits.
+
+    y1 := yLow.
+    y2 := yHigh.
+
+    srcIndex := 1 + (((width * yLow) + x) * 3).
+
+    y1 to:y2 do:[:y |
+        rVal := bytes at:(srcIndex).
+        gVal := bytes at:(srcIndex + 1).
+        bVal := bytes at:(srcIndex + 2).
+        srcIndex := srcIndex + width.
+
+        (rVal == lastR and:[gVal == lastG and:[bVal == lastB]]) ifFalse:[
+            lastColor := Color redByte:rVal greenByte:gVal blueByte:bVal.
+            lastR := rVal.
+            lastG := gVal.
+            lastB := bVal.
+        ].
+        aBlock value:y value:lastColor
+    ]
+!
+
 colorsAtY:y from:xLow to:xHigh do:aBlock
     "perform aBlock for each pixel from x1 to x2 in row y.
      The block is passed the color at each pixel.
@@ -3064,5 +3107,5 @@
 !Depth24Image class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libview/Depth24Image.st,v 1.89 2007-10-30 19:58:14 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libview/Depth24Image.st,v 1.90 2008-12-22 14:33:07 cg Exp $'
 ! !