Frequently Asked Questions

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4. How do I convert video between different formats with free software?

HandBrake is a GUI open source video transcoder.

HandBrake is available for Windows, Mac, Linux etc.


Mencoder is part of Mplayer, a video player. Mencoder is a command-line open source video transcoder.

Mencoder is available for Windows, Mac, Linux etc.

  1. Download Mplayer at
  2. Run the command line tool mencoder by starting the cmd. If you don't know what this is then don't follow this instruction. You have to have mencoder in your path.
  3. mencoder.exe input.avi -occ x264 -oac mp3lame -o output.mp4

  4. The new file named theoutput.mp4 should then contain the movie in the new x264 (mp4) format.


FFmpeg can be used as a command line open source tool for transcoding video.

ffmpeg -i input.avi output.mp4

Bitrate and quality

FFmpeg can also be used to convert between different bitrates. Please read the FFmpeg H.264 Video Encoding Guide.

ffmpeg -i input.avi -acodec coy -vcodec libx264 -crf 40 slioutput.mp4

The videos displayed below has been converted to different quality levels with the folling comand.

gforce:Movies jerker$ for i in 1 30 40 ; do ffmpeg -i big_buck_bunny_240p_1mb.mp4 -preset veryslow -acodec copy -vcodec libx264 -crf $i big_buck_bunny_240p_FFMPEG_CRF_${i}.mp4 ; done

From left to right are the original, the best quality, slightly lower quality and quite bad quality.

gforce:Movies jerker$ ls -la big_buck_bunny_240p_* -rw-r--r-- 1 jerker staff 1053651 Jun 17 2016 big_buck_bunny_240p_1mb.mp4 -rw-r--r-- 1 jerker staff 2199681 Jun 13 13:07 big_buck_bunny_240p_FFMPEG_CRF_1.mp4 -rw-r--r-- 1 jerker staff 742577 Jun 13 13:07 big_buck_bunny_240p_FFMPEG_CRF_30.mp4 -rw-r--r-- 1 jerker staff 692186 Jun 13 13:07 big_buck_bunny_240p_FFMPEG_CRF_40.mp4 gforce:Movies jerker$

The annotation on the poster image was made like this, following the examples at ImageMagick v6 Examples - Compound Font Effects.

TEXT="My text" convert source_image.png -font "Arial" -pointsize 50 \ -draw "fill black text 27,77 '$TEXT' \ text 25,78 '$TEXT' \ text 23,77 '$TEXT' \ text 22,75 '$TEXT' \ text 23,73 '$TEXT' \ text 25,72 '$TEXT' \ text 27,73 '$TEXT' \ text 28,75 '$TEXT' \ fill white text 25,75 '$TEXT' " \ poster.png

Read more about the sample video at Wikipedia.

This entry was last modified 2018-06-15

This documentation is covered by GNU Free Documentation License.