[FFmpeg-user] ffplay frustrations/questions/suggestions

[Marton Balint]

On Sat, 12 Nov 2016, Toerless Eckert wrote:

> It is possible with ffplay to use "-devices" to list output devices, but i could
> not find in ffplay(8) or "ffplay --help" or http://ffmpeg.org any indication how
> to SELECT a particular output device to use.
>
>  If there is no option to select the output device, i would suggest:
>  - Document that there is no such option, eg: following the documentation for
>    "-devices".
>  - Print in the output of "-devices" which the actual current output device is.
>
>  If there is an option, pls. let me know and document.
>

ffplay can't use libavdevice output devices, it uses the SDL drivers.

> With latest git version (3.2.git), ffplay does not work and gives the following
> error: "SDL: could not set video mode - exiting". This is running ffmpeg/ffplay
> on linux with environment variable DISPLAY set to remote X display (Mac, XQuartz).
>
> ffplay -devices lists:
>    sdl,sdl2        SDL2 output device
>    (and more)
>
> Older versions of ffmpeg (tried <= 2.8x) did work fine with my display
> setup and ddplay, but in those versions, ffplay and ffmpeg only include sdl
> (not sdl2).
>
> But also: latest ffmpeg works fine with either SDL or SDL2 with the same setup:
>    ffmpeg -i <input> -f [sdl|sdl2] "Window Title"
> aka: in same compile, only ffplay does not work with SDL...

That may be caused by the reason that ffplay currently wants to use a 
hardware accelerated renderer with VSYNC support. I guess a fallback can 
be implemented to use any available renderer if that fails.

> Finally: in latest git, ffplay is not even built without SDL2 library
> discovered on the system. That doesn't seem to be right either.

Why? FFplay does need SDL2, it can't work without it.

Regards,
Marton