--- a/Depth1Image.st	Tue Aug 30 16:07:42 2016 +0200
+++ b/Depth1Image.st	Tue Aug 30 16:08:07 2016 +0200
@@ -69,7 +69,7 @@
 !Depth1Image methodsFor:'accessing-pixels'!
 
 pixelAtX:x y:y
-    "retrieve a pixelValue at x/y; return a number.
+    "retrieve a pixelValue at x/y; return a pixel value.
      The interpretation of the returned value depends on the photometric
      and the colormap. See also Image>>atX:y:)
      Pixels start at 0@0 for upper left pixel, end at
@@ -118,6 +118,8 @@
 
 pixelAtX:x y:y put:aPixelValue
     "set a pixels value at x/y to aPixelValue.
+     The interpretation of the pixelValue depends on the photometric
+     and the colormap. (see also: Image>>atX:y:put:)
      Pixels start at x=0 , y=0 for upper left pixel, end at
      x = width-1, y=height-1 for lower right pixel"
 
@@ -131,20 +133,20 @@
     OBJ w = __INST(width);
 
     if (__isByteArray(b) && __bothSmallInteger(x, y) && __isSmallInteger(w) ) {
-	int _w = __intVal(w);
-	int _y = __intVal(y);
-	int _x = __intVal(x);
-	int _idx;
+        int _w = __intVal(w);
+        int _y = __intVal(y);
+        int _x = __intVal(x);
+        int _idx;
 
-	_idx = ((_w + 7) >> 3) * _y + (_x >> 3);
-	if ((unsigned)_idx < __byteArraySize(b)) {
-	    if (aPixelValue == __MKSMALLINT(0)) {
-		__ByteArrayInstPtr(b)->ba_element[_idx] &= ~(0x80 >> (_x & 7));
-	    } else {
-		__ByteArrayInstPtr(b)->ba_element[_idx] |= (0x80 >> (_x & 7));
-	    }
-	    RETURN( self );
-	}
+        _idx = ((_w + 7) >> 3) * _y + (_x >> 3);
+        if ((unsigned)_idx < __byteArraySize(b)) {
+            if (aPixelValue == __MKSMALLINT(0)) {
+                __ByteArrayInstPtr(b)->ba_element[_idx] &= ~(0x80 >> (_x & 7));
+            } else {
+                __ByteArrayInstPtr(b)->ba_element[_idx] |= (0x80 >> (_x & 7));
+            }
+            RETURN( self );
+        }
     }
 %}.
     "fall back code for nonByteArray or nonInteger arguments"
@@ -155,9 +157,9 @@
     byte := bytes at:index.
     mask := #(16r80 16r40 16r20 16r10 16r08 16r04 16r02 16r01) at:((x \\ 8) + 1).
     aPixelValue == 0 ifTrue:[
-	byte := byte bitAnd:(mask bitInvert)
+        byte := byte bitAnd:(mask bitInvert)
     ] ifFalse:[
-	byte := byte bitOr:mask
+        byte := byte bitOr:mask
     ].
     bytes at:index put:byte
 ! !