SDL_Window and SDL YUV Overlay?

Hi All, I wanted to embed an SDL rendering window (SDL YUV overlay
since my video data is in YUV format) within another window (parent)
at different positions and with different sizes,
and it seems that there is no way to do it with regular SDL_Init ,
SDL_SetVideoMode which autometically creates an window at some
predefined location. So I wanted to do something like the SDL examples
common.c and testsprite2.c, a blend of the two and the functions I am
calling are (in this order):


While I am hoping that these give me a nice borderless window that I
can position anywhere within another window (parent), I am clueless as
to how to create an YUV overlay on this window. SDL_CreateYUVOverlay
takes an SDL_Surface but I can’t figure out how I can get an
SDL_Surface out of this window. There is a SDL_GetVideoSurface() that
I tried but when I use the returned surface to create my YUVOverlay
the program crashes. Does anybody have any suggestions?