int width;
int height;
int rowstride;
bool has_alpha;
int bits_per_sample;
int channels;
weak Array<uint8> data;

//hints is a GLib.HashTable<string, Variant>
hints.lookup ("image_data").get ("(iiibiiay)", out width, out height, out rowstride,
     out has_alpha, out bits_per_sample, out channels, out data);

var pix = new Gdk.Pixbuf.from_data ((uint8[])data, Gdk.Colorspace.RGB, has_alpha,
    bits_per_sample, width, height, rowstride, null);