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on the ffmpeg Vorbis encoder
maikmerten
Archive.org now has all moving images content also available as Ogg Vorbis + Theora. This is great!

This was a massive reencoding effort and the details of what tools were used are available at http://internetarchive.wordpress.com/2008/11/25/fast-and-reliable-way-to-encode-theora-ogg-videos-using-ffmpeg-libtheora-and-liboggz/

A setup to get the job done. However, after having had a closer look I discovered that the Vorbis encodings were done with e.g.

ffmpeg -y -i CapeCodMarsh.avi -vn -acodec vorbis -ac 2 -ab 128k -ar 44100 audio.ogg

Ooops. This means there's massive amount of content, encoded with libavcodec's Vorbis encoder. The only problem: That encoder is rather primitive and produces significantly inferior audio quality compared to libvorbis. And yup, the Archive.org encodings sound rather unpleasant despite not starving on bitrate.

How I wished ffmpeg would loudly complain whenever using unfinished/experimental/not-state-of-the-art encoders.
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Re: Vorbis stuff in Moonlight?

Well, it's highly unlikely I'll be able to deliver Ogg support for Moonlight - I'm a complete stranger to Moonlight's subsystems and quite frankly: I see Silverlight as a hostile effort by Microsoft to undermine the multi-vendor-open-standards ecosystem of the Web, so while *I applaud* Moonlight's mission to not let Unix/Linux user left out in the rain I think I'll only begin to fully appreciate that once/if Silverlight becomes unavoidable.

(I have the suspicion Microsoft will deliberately keep Internet Explorer pretty outdated in terms of new web standards (SVG, media elements) to make a case for Silverlight)

Note that I have a pretty similar dislike for Adobe's Flash.

Wow, that was vastly offtopic and had lots of tinfoil-hat-theories.

Anyway, having Ogg in Moonlight would still be a good thing - upping the Ogg-enabled-application-count is always a good thing.

As for the "anyone who claims that Ogg isn't violating patents is a lunatic": The "MPEG patents" are pretty specific and of course it's possible to do video coding in different ways (although you won't be able to create valid MPEG streams, of course). Companies like On2 make a living out of avoiding 3rd-party coding patents - and I bet MPEG-LA would love to sue On2 for VP3 (technological base for Theora) and VP6/VP7 (Flash video, JavaFX video) if their patent pool would enable them to do so and succeed.

We're convinced that Ogg codecs build upon technologies with patents long expired or upon general prior art. Theora's bitstream basically is a decade old and has been used commercially a long time ago (VP3) - plus quite frankly there's nothing in there that is really innovative. No bidirectional prediction. No support for interlacing. No quarter-pixel precision used in the motion-compensation. No fancy entropy coding, just old Huffman. It's hard to imagine a to-this-day valid patent claim.

What channel was this IRC log from, if I may ask?

Re: Vorbis stuff in Moonlight?

irc.gimp.net #mono

Yeah, I feel the same way. I've been doing web development for a while, and having to deal with the proprietary Flash plug-in is a pain. At least with Moonlight I can poke at the code. Patents are too easy to misuse. Tinfoil-hat theories aren't always *entirely* off ;)

If you know anybody who's interested in adding Ogg support to Moonlight, let me (or the moon devs) know, and we'll help them get a dev environment all set up and ready for patching.

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