Hello Christian, Thanks for your guidance! I took a look at semantic_at_c() and get_color() and they seem to do the trick! Here's a couple of more questions. I've posted a compiling, annotated code at http://boost.codepad.org/Fy2vP73l Below is the more elaborate description of my questions which can be found in the code: 1. Can I specify which channel to get in nth_channel_view()? For example, if I want to set the red channel to 255 for all the pixels, I would do gil::fil_pixels(gil::nth_channel_view(view, 0), 255). However, that only works if our view is rgb8 or bgr8, not argb8. Is there a way I can say something like gil::fill_pixels(gil::nth_channel_view(view, gil::find_channel_for_view(view, gil::red_t())), 255) ??? 2. This compiles gil::gil_function_requires<gil::ImageViewConcept<int> >(); Strange. Any ideas? Best regards, Chris Yuen P.S. I am definitely interested in reviewing the extension! Apparently I'm a begginer in GIL. How would you like me to review and where should I write to?