int cmp_image(struct image *a, struct image *b);
void blit_image(struct image *src, int sx, int sy, int w, int h, struct image *dst, int dx, int dy);
int cmp_image(struct image *a, struct image *b);
void blit_image(struct image *src, int sx, int sy, int w, int h, struct image *dst, int dx, int dy);