January 12, 2006

PS vs ES, DVDs: VOBs and IFOs

What's the difference between PS and ES? Both are referenced in VideoLAN and the assumption is the reader knows what they are.

Well, here's a simple description (since I'm just learning it myself): PS stands for Program Stream and contains both video and audio. ES is Elementary Stream wherein the video stream is separate from the audio stream. The video stream is normally an M2V or an MPV file and the audio is stored in MPA, M2A or AC3. Generally, neither PS nor ES files are readable by DVD players.

DVD players typically read VOBs which are very closely related to files in the PS format. The VIDEO_TS folder on a DVD will contain both VOBs and IFOs. No VOB can be larger than 1GB so the IFO tells the player how to combine the VOBs into the original program. If you want to join together all VOBs into a single file, you can somply concatenate them (Linux: cat *.VOB > one-big-vob.mpg, Windows: copy /b vob1.vob + vob2.vob + vob3.vob one-big-vob.mpg -- thanks to Video Redo for a lot of this information, including the Windows copy command).

Posted by tony at 08:05 AM | Comments (0)

January 10, 2006

Compendium of digital formats

The federal government does some good work at time, despite the best efforts of our politicians! The Library of Congress has a wealth of information available over the web. In particular, the National Digital Information Infrastructure and Preservation Program (NDIIPP) has a catalog of various digital formats, categorized or alphabetical. It discusses AVI, for instance, its various subtypes (e.g. AVI_Cinepak and AVI_MJPEG) as well as what it may contain (e.g. WAVE and MP3_CPR).

Excellent resource for newbies like me!

Posted by tony at 01:30 PM | Comments (0)

January 08, 2006

Answering questions re: DVD authoring

This Afterdawn forum entry answers a lot of questions about DVD authoring (see the Wikipedia entry here.) Note that it does not cover transcoding, that is, the converting of one video or audio format into another. I'll post an entry about codecs and such shortly.

Guess what I'm doing :)

Posted by tony at 08:52 AM | Comments (0)