Boost C++ Application Development Cookbook - Second Edition

How it works...

At step 2, we are describing the types of images we wish to work with. These images are gray images with 8 and 16 bits per pixel and RGB pictures with 8 bits per pixel.

The boost::gil::any_image<img_types> class is a kind of Boost.Variant that may hold an image of one of the img_types variables. As you may have already guessed, boost::gil::png_read_image reads images into image variables.

The boost::gil::apply_operation function at step 4 is almost equal to boost::apply_visitor from the Boost.Variant library. Note the usage of view(source). The boost::gil::view function constructs a light wrapper around the image that interprets it as a two-dimensional array of pixels.

Do you remember that for Boost.Variant we were deriving ...