Open Source for Mac OS X

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.

Outputs:

• 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)

Misc features:

• Chapter selection
• Subtitles
• Integrated bitrate calculator
• Picture deinterlacing, cropping and scaling
• Live Video Preview