The formula used for converting between YUV and RGB
Defined in SDL_surface.h
typedef enum SDL_YUV_CONVERSION_MODE
{/**< Full range JPEG */
SDL_YUV_CONVERSION_JPEG, /**< BT.601 (the default) */
SDL_YUV_CONVERSION_BT601, /**< BT.709 */
SDL_YUV_CONVERSION_BT709, /**< BT.601 for SD content, BT.709 for HD content */
SDL_YUV_CONVERSION_AUTOMATIC } SDL_YUV_CONVERSION_MODE;