[FFmpeg-user] ffmpeg screencapture from a virtual xserver larger than the physical screen

[Zenny]

On 11/19/15, Zenny <garbytrash at gmail.com> wrote:
> On 11/19/15, Nicolas George <george at nsup.org> wrote:
>> Le nonidi 29 brumaire, an CCXXIV, Zenny a écrit :
>>> However, I have never forwarded xserver display with ffmpeg. Any hints
>>> appreciated.
>>
>> There is nothing special:
>>
>> ffmpeg -f x11grab -i :0 -f opengl -
>>
>> The first half grabs the display, the second half displays the resulting
>> video stream in a window. You can use all the options you want to scale
>> down, reduce rate, etc.
>
> I tried with:
>
> $ ffmpeg -f x11grab -s 3840x2160 -i :99 -r 24 -s 1280x720 -f opengl
> "4k_window" -
>
> as well as simply:
>
> $ ffmpeg -f x11grab -i :99 -f opengl -
>
> Both of the times, I got:
>
> "[NULL @ 0x3d89f60] Requested output format 'opengl' is not a suitable
> output format
> pipe:: Invalid argument"


Gotcha: The static build as well as the binary with
ppa:m3man/trusty-media both seems to have built ffmpeg without
'-enable-opengl' option as I can see:

ffmpeg version N-50328-g5911eeb-static
http://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2015 the FFmpeg
developers
  built with gcc 4.9.3 (Debian 4.9.3-4)
  configuration: --enable-gpl --enable-version3 --disable-shared
--disable-debug --enable-runtime-cpudetect --enable-libmp3lame
--enable-libx264 --enable-libx265 --enable-libwebp --enable-libspeex
--enable-libvorbis --enable-libvpx --enable-libfreetype
--enable-fontconfig --enable-libxvid --enable-libopencore-amrnb
--enable-libopencore-amrwb --enable-libtheora --enable-libvo-aacenc
--enable-libvo-amrwbenc --enable-gray --enable-libopenjpeg
--enable-libopus --enable-libass --enable-gnutls --enable-libvidstab
--enable-libsoxr --enable-frei0r --enable-libfribidi --cc=gcc-4.9

>
>
>>
>> Regards,
>>
>> --
>>   Nicolas George
>>
>