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Ogg conversion very bad quality

Is there any way to adjust the settings of ogg theora? It's coming out looking like 8-bit and super lo res.

9 people have this problem

maybe you can try some other audio or video conversion software that can convert video to MP3 or MP4 or other types formats with least loss of quality to ensure the audio bitrate.

Worked for me - thx!


i am converting mov to mp4. but the audio quality is very bad. Any solution for the high quality audio of the mp4 video??

Here's a quick solution for Windows users who are frustrated by this issue, but don't want to recompile the application from source.

Create a new text file and name it OGG_Vid.bat

Edit the file and paste in this code:

"C:\Program Files (x86)\Participatory Culture Foundation\Miro Video Converter\ffmpeg\ffmpeg.exe" -i %1 -codec:v libtheora -qscale:v 7 -codec:a libvorbis -qscale:a 5 %2

Save the file

Open command line (cmd.exe)
Drag in OGG_Vid.bat
Type one space

Drag in the source video
Type one space
Type in some output file name: output.ogv

Command should look similar to this (if your files are all on the desktop): 

C:\Users\YOU\Desktop\OGG_Vid.bat C:\Users\YOU\Desktop\input.avi C:\Users\YOU\Desktop\output.ogv

Press Enter

This will run the ffmpeg install included with Miro but set the quality levels higher. If you want to mess with the quality levels you can simply modify the numbers after the "qscale" parameter in the .bat file. I've included the file I created for this as well.

(167 Bytes)

 I wasn't able to follow some of the suggestions here but sure appreciate the suggested help! Until Mira gets the OGG quality issue fixed, I found an open source converter that can "batch" convert at good quality and reasonable file size.

Search: theora converter sourceforge

The default quality setting for the OGG Theora conversion is 6 (ranging from 1 to 10) , and that seems to be good for me. FYI, when I unzipped the theora converter, instead of installing automatically I had to find the unzip location and then click the install again. After that it works well, and is the only converter I've found so far that has good quality video and also batch-convert (can convert more than one file at a time)

From the libtheora documentation:

-qscale:v – video quality. Range is 0–10, where 10 is highest quality. 5–7 is a good range to try. If you omit -qscale:v (or the alias -q:v) then ffmpeg will use the default -b:v 200k which will most likely provide a poor quality output.

I've submitted a pull request ( if anyone wants to follow along.

Here's what I did:

#1. drag and drop your Miro Video Converter app onto your desktop.

#2. Rename the app to 'miro'

#3. Right mouse click the app and click "show package contents"

double click "Contents" then "Resources" then "lib" then "python2.7" then "mvc"

#4. Edit "" in your favourite editor or in text edit

#5. Replace line '43' with:

parameters = '-f ogg -vcodec libtheora -c:v libtheora -c:a libvorbis -q:v 4'

#6. Open terminal

#7. copy paste this and hit enter:

cd ~/Desktop/

#8. copy paste this and hit enter:

python -m compileall .

Don't forget the period at the end.

*Thanks to Phil for the solution*

Check my website for free downloads & web design tips!

so how do we implement this fix (and do the work for the developers)?

Yep, that fixed it, thanks Phil! Do you work at Miro or are you just smarter and harder working than they are?

Hi Phil,
thanks a lot for this comment. I've tried this and your are absolutely right. It works well. I have only one thing to mention: The filesize of my Demo-Video increased by 277% (2.2 MB to 6.1 MB).
But as you mentioned, i'll have to play around with the qualitysettings.


I guess you can play around with quality, I assume q:v is video quality, and that 10 is best.
So another example could be: -c:v libtheora -q:v 7 -c:a libvorbis -q:a 3 filename2.ogv


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.)

Windows and mac latest versions are equally bad at converting to Ogg Theora.  This is a deal breaker.

A google search for 'miro video converter older versions' includes links to older downloads. I'm off to test just now.



I have the same Problem. Can anyone tell me where I can get Miroconverter Version 2.6. so i can make Ogg Theroa in good quality?

Thanks for Info


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