type image = {width : int;height : int;rgba : (int, Stdlib.Bigarray.int8_unsigned_elt, Stdlib.Bigarray.c_layout)
Stdlib.Bigarray.Array1.t;
}val sample_nearest : image -> u:float -> v:float -> int * int * intval sample_bilinear : image -> u:float -> v:float -> int * int * int