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[Debconf-video] Re-encoding dc17

Hi folks,

So after getting comments that the encoding was very very low quality, I
checked around and found that the default settings for VP8 in ffmpeg are
way too low, and that if you don't fiddle with the right command-line
options, the quality won't be what you expect.

I fixed that in my script, and after a lot of experimentation, the
result is:


The quality is about on par for the two files, but the VP8 file is 428M
while the VP9 one is 341M. Unfortunately, the VP9 one does not load in
Firefox, which claims that the file is "corrupt"[1]. On my sid laptop, I
managed to get it to play in mpv, vlc, and Chromium, though.

I've copied all the files in the dc17 directory to an "lq" directory, so
that people can continue to download the low-quality version if they so
please. They are copied, not moved, so that the website will continue to
work; it will just get better-quality videos as the reencodes get
pushed on top of the "old" encodes.

Please test. If you see anything wrong with it, let me know. If I don't
hear any complaints, I plan to queue up all talks so they're encoded as
VP8 and VP9 in the above manner sometime early next week.


[1] while trying to load it, firefox nightly produces this on the
    command line:

[vp9 @ 0x7f942f298000] Failed to initialize decoder for 1280x720 @ 4
[vp9 @ 0x7f942f2a1800] Not all references are available
[vp9 @ 0x7f942f2e4800] Not all references are available
[vp9 @ 0x7f942f416800] Not all references are available

Not sure what's going on, but maybe someone here does?

Could you people please use IRC like normal people?!?

  -- Amaya Rodrigo Sastre, trying to quiet down the buzz in the DebConf 2008

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