+unsigned int get_pixel(struct image *img, int x, int y);
+unsigned int get_pixel_rgb(struct image *img, int x, int y, unsigned int *rgb);
+void put_pixel(struct image *img, int x, int y, unsigned int pix);
+
+void quantize_image(struct image *img, int maxcol);
+int gen_shade_lut(struct image *img, int levels, int maxcol, struct cmapent *shade_cmap,
+ int *shade_lut);
+