dtruett,
MP4 is the extension used for MPEG-4 files. Broadcasters and cable providers use the MPEG-2 (MPG) format. Apple does not include MPEG-2 support with OSX because that would cost them an extra 50 cents per copy in licensing fees.
Quicktime can play MPEG-2 files with an add-on. Apple charges $20 extra for that -- it's called the
Apple Quicktime MPEG-2 Playback Component. Just be aware that Quicktime still won't decode DD5.1 audio (even with that add-on).
A quick search on TivoCommunity shows that VLC isn't the most reliable software for viewing TiVo recordings on a Mac. Roxio Toast Titanium
v8.03 and Popcorn
v3.02 seem to be the best means of playing TiVo files on the Mac. Those programs allow you to create DVDs and convert the files for use with your portable video player, but neither allows you to edit the video.
So how do you edit the video? From the
MRV/TTG/TTCB FAQ:
Quote:
How do I remove commercials from my TiVo recordings?
On the Mac, no applications exist to automatically remove commercials from a recording. However, if you already have the
Apple Quicktime MPEG-2 Playback Component ($20) installed, you can use
MPEG Streamclip for OSX (free) to manually remove commercials on recordings you've downloaded with
TiVo Decode Manager. Once you've marked the commercials for removal as explained in the Streamclip Guide (Help menu), set the Audio Mode to "Surround", and click "Save As" to save the edited file in MPEG format.
Credit for this bit goes to member hearncl.
On Windows, several different programs exist to automatically remove commercials from a recording. By far the easiest and most popular program for this task is
VideoRedo (
14-day trial, $50 to buy). With VideoRedo, you open the TiVo recording, select "Start Ad-Detective Scan" to automatically detect and mark the commercials for deletion, and then click "save" to save the recording with commercials removed (
screenshot).
[snip]
If you just want to convert videos for your portable video player, you might want to try
VisualHub. Many prefer that to Roxio Popcorn. VisualHub will also convert files to MP4 so they can be edited with iMovie, etc, although be aware that MPEG-2 to MPEG-4 conversion can be quite time-consuming. VisualHub does let you queue up as many conversions as you want, so it will continue working while you are asleep / at work.
If you're looking for free software to convert the MPEG-2 recordings to MPEG-4, then take a look at
Handbrake for OSX. It's more complicated than
VisualHub, but it is free.