Re: [LAD] Screencasting with JACK [SOLVED!]

On Thu, Aug 8, 2013 at 6:54 PM, J. Liles <malnourite@email-addr-hidden> wrote:

>
> As some of you may recall, every time I've posted a demo video to LAD,
> I've had to include a disclaimer excusing the poor quality due to a lack of
> functional screencasting tools.
>
> Well, it took a couple of weeks of hair pulling and many, many hours of
> testing, but I finally arrived at a solution.
>
> Anyone who wants to create a screencast and record audio via JACK *in
> perfect sync* must do the following:
>
> Get ffmpeg. Apply this patch to it:
>
>
> https://github.com/original-male/FFmpeg/commit/d02509d04d396a98646ca81e9ba327a501486130.patch
>
> Build it with vorbis and h264 support.
>
> Then, start your favorite desktop environment. I use Xephyr for this.
>
> Have jack running (at -r 48000)
>
> Then run the following command:
>
> ffmpeg -fflags +genpts+igndts -f x11grab -vsync 0 -r 30 -s 1920x1080 -i
> :${DISPLAY}.+0,0 -vcodec h264 -f jack -ac 2 -r:a 48000 -i screencast
> -acodec pcm_s16le -r:v 30 -vsync 2 -async 1 -map 0:0,1,0 -map 1:0 -preset
> ultrafast -qp 0 "$FILE"
>
> Where DISPLAY is the number of your X11 display and FILE is the filename
> for the screencast. I use a .mkv extension for the matroska container.
>
> Remember to connect the streams you want recorded to the 'screencast' JACK
> inputs!
>
> With this setup I'm able to record a full 30 FPS @ 1080P with audio in
> perfect sync. Please share your results too. With some more evidence I
> might have a good case to get ffmpeg to accept my patch.
>
> Enjoy!
>
>
>
>
>
>
>
Forgot to mention, use at least these options when configuring ffmpeg:

./configure --enable-libx264 --enable-x11grab --enable-gpl
--enable-libvorbis

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Received on Fri Aug 9 16:15:02 2013