Hi All, The following code is straight out of the tutorial about making function generic. Can anyone suggest how I might determine the layout of DstView here so that I can build an image of the same layout? In this example they hardcode gray_layout_t and I'm not seeing any metafunctions that return the layout. template <typename SrcView, typename DstView> void x_luminosity_gradient(const SrcView& src, const DstView& dst) { typedef typename channel_type<DstView>::type d_channel_t; typedef typename channel_convert_to_unsigned<d_channel_t>::type channel_t; typedef typename image_type<channel_t, gray_layout_t>::type gray_image_t; typedef typename gray_image_t::value_type gray_pixel_t; gray_image_t ccv_image(src.dimensions()); copy_and_convert_pixels(src, view(ccv_image)); x_gradient(const_view(ccv_image), dst); } Thanks, Mark Notice: This e-mail is intended solely for use of the individual or entity to which it is addressed and may contain information that is proprietary, privileged, company confidential and/or exempt from disclosure under applicable law. If the reader is not the intended recipient or agent responsible for delivering the message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. If this communication has been transmitted from a U.S. location it may also contain data subject to the International Traffic in Arms Regulations or U.S. Export Administration Regulations and cannot be disseminated, distributed or copied to foreign nationals, residing in the U.S. or abroad, without the prior approval of the U.S. Department of State or appropriate export licensing authority. If you have received this communication in error, please notify the sender by reply e-mail or collect telephone call and delete or destroy all copies of this e-mail message, any physical copies made of this e-mail message and/or any file attachment(s).