HandBrake is an open-source, GPL-licensed, multiplatform, multithreaded video transcoder.
* Any DVD-like source: VIDEO_TS folder, DVD image or real DVD (unencrypted--protection methods including CSS are not supported internally and must be handled externally with third-party software and libraries), and some .VOB and .TS files
* Most any multimedia file it can get libavformat to read and libavcodec to decode.
* File format: MP4 and MKV
* Video: MPEG-4, H.264, or Theora
* Audio: AAC, CoreAudio AAC (OS X Only), MP3, or Vorbis. AC-3 pass-through, DTS pass-thorugh (MKV only)
* Chapter selection
* Integrated bitrate calculator
* Picture deinterlacing, cropping and scaling
* Live Video Preview
Home Page - http://handbrake.fr/details.php