I'm in doubts that `uchar3` works correctly (reason: http://www.khronos.org/registry/cl/sdk/1.2/docs/man/xhtml/dataTypes.html `For 3-component vector data types, the size of the data type is 4 * sizeof(component).`)
But since this code is called on Intel only and you (as an Intel guy) should have tested this on Intel devices - let's merge this.