Hi,
I cannot recreate your problem. Here is a little test app that works fine on my machine ( VC10 )
The problem is that I define a generic conversion like that: /// \ingroup ColorConvert /// \brief Converting HSL to any pixel type. Note: Supports homogeneous pixels only. /// /// Done by an intermediate RGB conversion template <typename C2> struct default_color_converter_impl<hsl_t,C2> { template <typename P1, typename P2> void operator()(const P1& src, P2& dst) const { typedef hsl_t C1; typedef typename channel_type<P1>::type T1; typedef typename channel_type<P2>::type T2; pixel<T2,rgb_layout_t> tmp; default_color_converter_impl<C1,rgb_t>()(src, tmp); default_color_converter_impl<rgb_t,C2>()(tmp, dst); } }; So it's in conflict with: template <typename C1> struct default_color_converter_impl<C1, rgba_t>, if I use color_convert( hslPixel, rgbaPixel ). The goal of creating this generic conversion is that I can still make the conversion using an intermediate rgb colorspace if there is no specialization. I think we can have a good solution, if we apply this method to all colorspaces: * define a generic conversion to another colorspace using an intermediate rgb colorspace conversion, only in one direction MyColorspace -> typename C2 (so without typename C1 -> MyColorspace). That's why I would like to remove typename C1 -> rgba_t implementation. * redefine the conversion for colorspaces we want to make a direct conversion