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From Sonia SWEngineer <swengineeru...@gmail.com>
Subject Re: Questions on Screen Recording
Date Fri, 24 May 2019 14:32:11 GMT
Thanks very much Maxim for your advice.

Best Regards,

Sonia

On Thu, May 23, 2019 at 11:37 PM Maxim Solodovnik <solomax666@gmail.com>
wrote:

> Hello,
>
> actually OM server code need to be corrected to receive "screen stream"
> from ffmpeg
> It requires some additional parameters to be passed
> And currently some parameter are passed in Red5 specific way [1]
>
> So the implementation I would implement:
> 1) check if ffmpeg is available on client machine
> 2) YES: create ffmpeg process with all required parameters (here is sort of
> example [2]) instead of Java encoder
> 3) NO: use java encoder
> 4*) contribute it back :)))
>
> [1]
>
> https://github.com/apache/openmeetings/blob/4.0.x/openmeetings-core/src/main/java/org/apache/openmeetings/core/remote/ScopeApplicationAdapter.java#L235
> [2] https://om.alteametasoft.com/openmeetings/docs/ExternalVideo.html
>
>
> On Thu, 23 May 2019 at 11:15, Sonia SWEngineer <swengineeruser@gmail.com>
> wrote:
>
> > Thanks very much Maxim. Yes, I meant better compression so the screen
> data
> > uses less bandwidth.
> > Regarding replacement of the current encoder with ffmpeg:
> > - Can this be achieved by streaming the screen with ffmpeg with options:
> -i
> > :0.0+0,0...-c:v libx264......-f flv rtmps://...?
> > - Or, by continue using the EncodeJob and SendJob logic but compressing
> the
> > image(s) with ffmpeg in the "encode" method before pushing them as
> > videoData?
> > If this is the way, then will ffmpeg need to output a
> ByteArrayOutputStream
> > that is compressed by libx264 in the encode method?
> >
> > Regards,
> >
> > Sonia
> >
> >
> >
> > On Wed, May 22, 2019 at 3:14 AM Maxim Solodovnik <solomax666@gmail.com>
> > wrote:
> >
> > > Hello Sonia,
> > >
> > > hand-made ScreenV1 codec is being used for screen-share
> > > the size of keyframe is roughly equals to width*height*4*scale (scale
> is
> > > calculated based on selected image quality [1])
> > > non key frame size depends on what was changed
> > >
> > > This hand-made encoder can be replaced with ffmpeg code modification
> will
> > > be required
> > >
> > > Do you mean "better compression" by "reduce the length of the encoded
> > > screen data"?
> > > If so you can use x264 compression, most probably will work better
> > >
> > >
> > > [1]
> > >
> > >
> >
> https://github.com/apache/openmeetings/blob/master/openmeetings-screenshare/src/main/java/org/apache/openmeetings/screenshare/gui/ScreenSharerFrame.java#L784
> > >
> > > On Wed, 22 May 2019 at 10:26, Sonia SWEngineer <
> swengineeruser@gmail.com
> > >
> > > wrote:
> > >
> > > > Good day all,
> > > > This message is to request your advice on the following questions
> > > regarding
> > > > Screen Recording:
> > > >
> > > > 1- What could be a rough estimate on how much bandwidth is needed for
> > > > screen recording with RTMPS using the Java applet?
> > > > The NetworkCalculator link below does not specify how much is needed
> > for
> > > > screen sharing/recording.
> > > > https://openmeetings.apache.org/NetworkCalculator.html
> > > >
> > > > 2-Are there open source or commercial options to reduce the length of
> > the
> > > > encoded screen data for RTMPS at this time?
> > > >
> > > > Thanks in advance for any advice on this regard.
> > > >
> > >
> > >
> > > --
> > > WBR
> > > Maxim aka solomax
> > >
> >
>
>
> --
> WBR
> Maxim aka solomax
>

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