rubeninmark / xuggle

Automatically exported from code.google.com/p/xuggle
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Improve Theora video quality #248

Open GoogleCodeExporter opened 9 years ago

GoogleCodeExporter commented 9 years ago
Theora video quality is really bad in my opinion and should be improved given 
its use in HTML5 and Unity. I would suggest replacing the theora encoder that 
ships with ffmpeg for the one from xiph or ffmpeg2theora as the later produces 
excellent quality video given the same source.

Original issue reported on code.google.com by mondain on 24 Aug 2010 at 5:33

GoogleCodeExporter commented 9 years ago
Even vanilla tip-of-tree ffmpeg itself, used from commandline w/ libtheora and 
default settings yields remarkably better results than tip-of-tree Xuggler w/ 
default settings and identical flv input video (using latest win32 binaries 
from http://ffmpeg.arrozcru.org/autobuilds/ and libmp3lame for audio).

For starters, the output file's size is about 4 times larger when working with 
vanilla ffmpeg. Even with the sameq flag enabled (and of course, without it too 
- it seems to have no effect), Xuggler just doesn't detect the correct quality 
settings to match the input video's quality, whereas command-line ffmpeg 
detects and uses suitable settings even without enabling this flag.

Original comment by ido.dov...@gmail.com on 26 Aug 2010 at 11:27

GoogleCodeExporter commented 9 years ago
It seems that this issue arises from the use of bad defaults. In the 
abovementioned example, ffmpeg.exe (the very version used as captive in 
Xuggler) defaulted to using a constant bitrate of 200k w/ a timebase of 1/25, 
whereas Xuggler defaulted to a variable bitrate w/ a timebase of 1/1000000.

Once the IStreamCoder is manually configured with the CBR settings, all is 
well. So the only issue here is that the default encoder settings used by 
Xuggler for Theora are pretty bad, and do not match FFMPEG's defaults.

Original comment by ido.dov...@gmail.com on 6 Sep 2010 at 12:57