Given a MP4 file...
Use MP4Box to extract into VOB/SUB format
First, find the info: /Volumes/GPAC\ for\ OSX/Osmo4.app/Contents/MacOS/MP4Box -info ~/Desktop/MOVIEFILE.m4v
* Movie Info *
Timescale 90000 - Duration 00:22:36.981
4 track(s)
Fragmented File: no
File suitable for progressive download (moov before mdat)
File Brand mp42 - version 0
Created: GMT Thu May 16 02:02:19 2013
File has root IOD (9 bytes)
Scene PL 0xff - Graphics PL 0xff - OD PL 0xff
Visual PL: ISO Reserved Profile (0x7f)
Audio PL: High Quality Audio Profile @ Level 2 (0x0f)
No streams included in root OD
iTunes Info:
Encoder Software: HandBrake 5454svn 2013051301
Track # 1 Info - TrackID 1 - TimeScale 90000 - Media Duration 00:22:36.981
Track has 1 edit lists: track duration is 00:22:36.981
Media Info: Language "Undetermined" - Type "vide:avc1" - 32534 samples
Visual Track layout: x=0 y=0 width=853 height=360
MPEG-4 Config: Visual Stream - ObjectTypeIndication 0x21
AVC/H264 Video - Visual Size 720 x 360
AVC Info: 1 SPS - 1 PPS - Profile Main @ Level 4
NAL Unit length bits: 32
Pixel Aspect Ratio 32:27 - Indicated track size 853 x 360
Self-synchronized
Track # 2 Info - TrackID 2 - TimeScale 48000 - Media Duration 00:22:36.949
Media Info: Language "French" - Type "soun:mp4a" - 63607 samples
MPEG-4 Config: Audio Stream - ObjectTypeIndication 0x40
MPEG-4 Audio AAC LC - 1 Channel(s) - SampleRate 48000
Synchronized on stream 1
Track # 3 Info - TrackID 3 - TimeScale 90000 - Media Duration 00:22:34.083
Media Info: Language "French" - Type "subp:mp4s" - 492 samples
MPEG-4 Config: NeroDigital Subpicture Stream - ObjectTypeIndication 0xe0
Synchronized on stream 1
Track # 4 Info - TrackID 4 - TimeScale 90000 - Media Duration 00:22:36.981
Track has 1 edit lists: track duration is 00:22:36.981
Track is disabled
Media Info: Language "Undetermined" - Type "text:text" - 5 samples
Timed Text - Size 0 x 0 - Translation X=0 Y=0 - Layer 0
/Volumes/GPAC\ for\ OSX/Osmo4.app/Contents/MacOS/MP4Box -raw 3 ~/Desktop/MOVIEFILE.m4v
Install Tesseract
brew install tesseract
Download the French language pack for tesseract https://code.google.com/p/tesseract-ocr/downloads/list
Copy to: /usr/local/Cellar/tesseract/3.02.02/share/tessdata
https://github.com/ruediger/VobSub2SRT
Download formula for vobsub2srt: brew install https://github.com/ruediger/VobSub2SRT/raw/master/packaging/vobsub2srt.rb
brew install --HEAD vobsub2srt