#include "SDL.h"
int SDL_LockYUVOverlay(SDL_Overlay *overlay);
Much the same as SDL_LockSurface, SDL_LockYUVOverlay locks the overlay for direct access to pixel data.
Returns 0 on success, or -1 on an error.
SDL_UnlockYUVOverlay, SDL_CreateYUVOverlay, SDL_Overlay