For hypothetical example, if the file would optimally choose a gray16 planar image, but I pass any_image<mpl::vector<rgb8_image_t, gray8_image_t> > to read_image, then I want the read_image function to create a gray8_image_t and convert the pixels to that.
I dont know how it would be done, but that would be a nice feature.
Yeah, sounds like a nice feature. I will make a mark in my todo list. Before I could tackle that I would need to overcome my template instantiation issue. I cannot even compile with MSVC 7.1. It's complaining:
fatal error C1055: compiler limit : out of keys
I think I need to seriously rethink the design.
Hmmm...
I think the other thing would be for each image format to have its own image_types typedef, to that I can read into an image variant that is perfect for the reader.
Not sure if I follow here.
any_supported_image<jpeg_tag> result; read_image(fname, result, jpeg_tag()) gil::apply_operation(result, my_operation) On another note, I dont think you need filesystem to check the extension of the images. You can use the boost string algorithms library (or just use std::string operations). bool can_read(std::string filename, jpeg_tag const& ){ static const string extensions[] = {".jpg", ".jpeg" }; return ::boost::algorithm::iends_with(filename, extensions[0]) || ::boost::algorithm::iends_with(filename, extensions[1]); } Also, I beleive some of the image formats can peek at the first few bytes of the file to determine if the format is appropriate. I dont know about non-windows systems, but on some of them this might be the only way to tell. If that is the way image formats are checked, then I dont think filesystem (or string algs) is going to be important. -- John