struct SwsContext* scale_context = sws_getContext (
size().width, size().height, pixel_format(),
content_size.width, content_size.height, PIX_FMT_RGB24,
struct SwsContext* scale_context = sws_getContext (
size().width, size().height, pixel_format(),
content_size.width, content_size.height, PIX_FMT_RGB24,