=== modified file 'src/com/goldencode/p2j/ui/client/gui/driver/web/res/p2j.canvas_renderer.js'
--- src/com/goldencode/p2j/ui/client/gui/driver/web/res/p2j.canvas_renderer.js	2015-12-16 13:35:36 +0000
+++ src/com/goldencode/p2j/ui/client/gui/driver/web/res/p2j.canvas_renderer.js	2016-01-11 17:33:23 +0000
@@ -20,6 +20,8 @@
 ** 005 SBI 20151205 Changed to adjust clipping regions according to a new origin.
 ** 006 SBI 20151216 Changed to work around that the Chrome's implementation of getImageData
 **                  rounds function parameters.
+**     SBI 20160111 Rewrite the copy of the target image taking into account the Chrome's
+**                  getImageData implementation.
 */
 
 "use strict";
@@ -432,15 +434,7 @@
    {
       var w = imageData.width;
       var h = imageData.height;
-      var screenShot;
-      if (p2j.isChrome)
-      {
-         screenShot = this.ctx.getImageData(Math.round(x), Math.round(y), w, h);
-      }
-      else
-      {
-         screenShot = this.ctx.getImageData(x, y, w, h);
-      }
+      var screenShot = this.ctx.getImageData(x, y, w, h);
       var pixelsInBytes = 4 * w * h;
       for (var i = 0; i < pixelsInBytes; i += 4)
       {
@@ -791,19 +785,79 @@
     * Pixels must be returned as non-premultiplied alpha values according to:
     * http://www.w3.org/TR/2dcontext/#pixel-manipulation
     */
-   var img;
+   var img = ctx.getImageData(xo, yo, width, height);
+   var data = img.data;
    if (p2j.isChrome)
    {
-      img = ctx.getImageData(Math.round(xo), Math.round(yo), width, height);
+      copyImage(img, data, imgData, width, height, imgDataOffset);
    }
    else
    {
-      img = ctx.getImageData(xo, yo, width, height);
-   }
-   var data = img.data;
-   var pixelsInBytes = width * height * 4;
+      // optimized version of copy image
+      var pixelsInBytes = width * height * 4;
+      var offset = imgDataOffset;
+      for (var p = 0; p < pixelsInBytes; p += 4, offset += 4)
+      {
+         var alpha = imgData[offset + 3];
+         var beta = 256 - alpha;
+         if (alpha == 255)
+         {
+            /** server sends non-premultiplied image data */
+            data[p]     = imgData[offset];
+            data[p + 1] = imgData[offset + 1];
+            data[p + 2] = imgData[offset + 2];
+            data[p + 3] = imgData[offset + 3];
+         }
+         else if (alpha > 0)
+         {
+            /** server sends non-premultiplied image data */
+            data[p]     = (imgData[offset]     * alpha + data[p]     * beta) >> 8;
+            data[p + 1] = (imgData[offset + 1] * alpha + data[p + 1] * beta) >> 8;
+            data[p + 2] = (imgData[offset + 2] * alpha + data[p + 2] * beta) >> 8;
+            data[p + 3] = (imgData[offset + 3] * alpha + data[p + 3] * beta) >> 8;
+         };
+      };
+   }
+   var deltaX = xa - xo;
+   var deltaY = ya - yo;
+   if (this.compositeModeOn)
+   {
+      this.applyCompositeMode(img, xo, yo);
+   }
+   this.ctx.putImageData(img, xo, yo, deltaX, deltaY, xb - xa, yb - ya);
+};
+
+/**
+ * Copies a downloaded image encodded as an rgba byte array provided with its width and its height
+ * to the screen image given by its own width and height taking into account the coppied image
+ * alpha channel and places it at the zero coordinates relative to the screen image.
+ * 
+ * @param    {ImageData} img
+ *           The screen image data
+ * @param    {Uint8ClampedArray} data
+ *           The screen image rgba byte array. 
+ * @param    {Array} imgData
+ *           The rgba byte array of the coppied image.
+ * @param    {Number} width
+ *           The coppied image width.
+ * @param    {Number} height
+ *           The coppied image height.
+ * @param    {Number} imgDataOffset
+ *           The coppied image data offset from the 0-index of its data array, imgData.
+ * 
+ * @return   {Uint8ClampedArray}
+ *           Returns the modified screen image data array with the target image.
+ *  
+ */
+function copyImage(img, data, imgData, width, height, imgDataOffset)
+{
+   var awidth  = img.width;
+   var aheight = img.height;
+   var x = 0;
+   var y = 0;
+   var pixelsInBytes = awidth * aheight * 4;
    var offset = imgDataOffset;
-   for (var p = 0; p < pixelsInBytes; p += 4, offset += 4)
+   for (var p = 0; p < pixelsInBytes; offset += 4)
    {
       var alpha = imgData[offset + 3];
       var beta = 256 - alpha;
@@ -823,14 +877,22 @@
          data[p + 2] = (imgData[offset + 2] * alpha + data[p + 2] * beta) >> 8;
          data[p + 3] = (imgData[offset + 3] * alpha + data[p + 3] * beta) >> 8;
       };
+      x++;
+      // p = (y * awidth + x) * 4
+      // p1 - p0 = [(y1 - y0) * awidth + (x1 - x0)] * 4 = 4 or 4 * (awidth - width) + 4 
+      if (x == width)
+      {
+         y++;
+         x = 0;
+         p += ((awidth - width + 1) * 4);
+      }
+      else
+      {
+         p += 4; 
+      }
    };
-   var deltaX = xa - xo;
-   var deltaY = ya - yo;
-   if (this.compositeModeOn)
-   {
-      this.applyCompositeMode(img, xo, yo);
-   }
-   this.ctx.putImageData(img, xo, yo, deltaX, deltaY, xb - xa, yb - ya);
+   
+   return data;
 };
 
 /**