Re: [Debconf-video] Videos of MiniDebConf Bucharest 2015 (Debian Women)
Hi Larjona,
On Thu, Oct 22, 2015 at 10:58:24PM +0200, Laura Arjona Reina wrote:
> Dear DebConf-Video team, Debian Women and Debian MiniDebConf Bucharest
> team:
>
> Marga passed to me several months ago an url to the RAW video files,
> named 00000.MTS to 00007.MTS
>
> I've watched all of them and uploaded to my site the ones with talks:
>
> http://cosas.larjona.net/2015_minidebconf_bucharest/
>
> (the others are recordings of the room while breaks etc).
>
> In that folder there is also a txt file with the hh:mm of cuts for the
> different talks.
>
> Note that I only have the talks of Saturday, I don't know if there are
> more videos in other place (sorry, I lost the original URL that Marga
> gave me too, I just downloaded the videos that were there, and didn't
> save the URL).
>
> I don't know if the video team may upload the videos plus the txt file
> for now, or better to finish the work first.
It's better to finish the work first, IMO.
> So, the pending work. I have no idea about video
> editing/transcoding/formats, but I suppose the next steps would be:
>
> 1.- Actually cut the videos, and transform them to webm format
> (ogg+theora vorbis). I suppose I can use openshot or kdenlive for
> that. I know how to cut the videos. I'm more lost about the format and
> quality desired for the output. If you can help me giving me the
> details about format resolution, fps or quality, whatever I have to
> tell to openshot o kdenlive in the "export" process, I'd be very
> thankful for that.
>
> 2.- If possible, enhance the audio (volume + deleting noise). I have
> no idea about how to do that, nor which tool to use.
>
> My best machine to do this work is a laptop year 2011 with AMD dual
> core processor E300, AMD Radeon HD 6310, and 6GB RAM, which runs
> Debian stable. I suppose it can do the work but may take days, that's
> why I'd like to know well in advance how to proceed.
>
> Any advice?
I would recommend against doing this in interactive tools. If you've
already looked at the videos and decided where the cuts need to be, then
entering those cuts in an interactive tool is just a waste of time. Far
faster to script all that.
I've blogged about this during Debconf:
http://grep.be/blog/en/computer/play/Multi-pass_transcoding_to_WebM_with_normalisation/
That post contains a perl script snippet which generates some shell
script that will do the cutting and audio normalisation for you with
another script that uses gstreamer and sox. Yes, it's terribly ugly, but
it should get you started. You may need to modify the "dv2webm" script
so that it has the appropriate settings for reading MTS files rather
than DV ones.
It doesn't have any specific settings for video quality (just uses the
gstreamer defaults), which seems to result in "use whatever bandwidth is
necessary", and I think that's a good default for non-live video
(obviously it isn't for live video, but then that's not what we need
here).
In addition, I've since learned that there is actually a broadcasting
standard about audio normalisation which the sox line in my script
doesn't do. There is a tool called "bs1770gain" in the archive which I'm
told does do so. I had decided not to change audio levels for debconf
anymore (since I learned about it halfway through debconf already, and I
wasn't sure I could finish all transcoding in time if I had changed it
anymore), but it's something I think we should do for future recordings.
I'm not very knowledgeable about the "cleaning up noise" part of doing
audio; you'll have to find someone else to figure that out. However, if
the noise is not too distracting and/or not too loud, I would suggest
you don't remove it; in a recording of a talk, it's actually beneficial
to have some minor background noise.
Other than that, if you've got any further questions, fire away.
--
It is easy to love a country that is famous for chocolate and beer
-- Barack Obama, speaking in Brussels, Belgium, 2014-03-26
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