Fix Miro 3.0 Ogg Conversion Quality

From the poster “Phil” on the Miro support forums…

In this directory/Terminal:
cd /Applications/Miro Video
Edited this file:
open -e

After these lines:
class OggTheora(converter.FFmpegConverterInfo):
media_type = ‘format’
extension = ‘ogv’
I replaced:
  parameters = ‘-f ogg -vcodec libtheora -acodec libvorbis -aq 10’
   parameters = ‘-f ogg -vcodec libtheora -c:v libtheora -c:a libvorbis -q:v 4’

Then ran python -m compileall .  in that directory in

Then I quit and re-started the Miro Video … Now I get better quality OggTheora …
(I actually also replaced ffmpeg in the Helpers dir with my own binary, but I don’t think mattered, as I had the same problem until I changed the config.)

Ogg conversion very bad quality : Miro Video Converter.


Converting AVI to MP4 with ffmpeg

Simple commands to convert video formats:

This command will provide an mp4 of lower quality.

ffmpeg -i input.avi -acodec libfaac -b:a 128k -vcodec mpeg4 -b:v 1200k -flags +aic+mv4 output.mp4

To maintain the video quality try adjusting the parameters: (-crf parameter will control quality – 23 is the ffmpeg default. The lower the number the higher quality the video will be, it will also take longer to convert.

ffmpeg -i input.avi -c:v libx264 -crf 19 -preset slow -c:a libfaac -b:a 192k -ac 2 out.mp4


Another tip for converting mkv files to mp4.

avconv -i input.mkv -codec copy output.mp4

FFMPEG Resources