pub unsafe extern "C" fn fz_new_pixmap_writer( ctx: *mut fz_context, path: *const c_char, options: *const c_char, default_path: *const c_char, n: c_int, save: Option<unsafe extern "C" fn(ctx: *mut fz_context, pix: *mut fz_pixmap, filename: *const c_char)>) -> *mut fz_document_writer