I have HostGator VPS server with FFmpeg installed. It allows me to convert .wmv to .flv as well as .mp4 files successfully using the following commands for flv and mp4: ffmpeg -i WantsABath.wmv -b 600k -r 24 -ar 22050 -ab 96k WantsABath.flv ffmpeg -i WantsABath.wmv WantsABath.mp4 but it won't allow me to convert any file format to .ogg. I tried using the command: ffmpeg -i input.mp4 -acodec libvorbis -vcodec libtheora -f ogv output.ogv by mondain but no luck with it. I am doubting that my VPS doesn't have libtheora installed. I tried configuring it by using SSH but I don't know how to make sure if it is installed or not. I tried checking with php_info but can't find anything regarding libtheora. Here's my FFmpeg version: FFmpeg version SVN-r19795, Copyright (c) 2000-2009 Fabrice Bellard, et al. configuration: --enable-libmp3lame --enable-libvorbis --disable-mmx --enable-shared --prefix=/usr/ --enable-gpl libavutil 50. 3. 0 / 50. 3. 0 libavcodec 52.35. 0 / 52.35. 0 libavformat 52.38. 0 / 52.38. 0 libavdevice 52. 2. 0 / 52. 2. 0 libswscale 0. 7. 1 / 0. 7. 1 This details doean't show libtheor Can anyone please suggest me something?