worldwide compatibility AC3 or MPEG ?

[piano632]

I want to burn DVDs that are playable on machines in North America, UK, Australia, etc. In the past I have used LPCM audio with success but this severely limits playing time. So the question is which audio format is more likely to be playable worldwide - AC3 or MPEG? I'm working with NTSC if that makes a difference. Also which audio bitrates are most compatible?

[lordsmurf]

AC3, 2/0 stereo, 192k-384, 224-256k is typical

[disturbed1]

MPEG audio is only a DVD spec in PAL, along with AC3 and LPCM. For NTSC it is AC3 or LPCM. Most NTSC players do play mpeg audio on authored DVDs though. But to be honest, if you're worried about 100% compliant, use AC3.

AC3 2/0 at 192kbit/s is the standard that studios use, also default for Scenarist's AC3 encoder in 2.0 mode and Soft Encode's 2/0 mode.

[piano632]

Well this is nice. I can just record on my JVC recorder, edit with Womble and author with TMPGEnc DVD Author without having to re-encode anything. Except I think the audio bitrate is 256k or 384k on the JVC recorder. I was under the impression that some DVD players didn't like high audio bitrates like 384k.

[scottie78]

MPEG audio is only a DVD spec in PAL, along with AC3 and LPCM. For NTSC it is AC3 or LPCM. Most NTSC players do play mpeg audio on authored DVDs though. But to be honest, if you're worried about 100% compliant, use AC3.

Up to 8 audio tracks containing DD (Dolby Digital/AC3), DTS, PCM(uncompressed audio), MPEG-1 Layer2. One audio track must have DD or PCM Audio.

MPEG is part of the NTSC spec, as long as there's at least one AC3 or LPCM stream somewhere on the disc.

For this reason, if you're only going to have one title, I'd stick with AC3.

[disturbed1]

The higher bitrate is just fine. If anything, it will make you think it sounds better since it uses a higher bitrate

[disturbed1]

MPEG audio is only a DVD spec in PAL, along with AC3 and LPCM. For NTSC it is AC3 or LPCM. Most NTSC players do play mpeg audio on authored DVDs though. But to be honest, if you're worried about 100% compliant, use AC3.

Up to 8 audio tracks containing DD (Dolby Digital/AC3), DTS, PCM(uncompressed audio), MPEG-1 Layer2. One audio track must have DD or PCM Audio.

MPEG is part of the NTSC spec, as long as there's at least one AC3 or LPCM stream somewhere on the disc.

Exactly.

Each video track must have either AC3 or LPCM on that track, not anywhere

Let's say you create a menu with LPCM, that does not mean that you can just add mp2 audio to every video track, it is a violation of standards. But you can create a video track with 2/0 AC3 as one audio track, then 7 channel mpeg2 audio as another channel, which is inside the standard.

If an object is to have mpeg audio, the same object must also have either ac3 or LPCM audio. With PAL, any audio format is valid. NTSC requires either LPCM or AC3, because not all players support MPEG audio on a DVD, which is why you have to include the option for additional ac3 and/or LPCM audio tracks.

[scottie78]

Each video track must have either AC3 or LPCM on that track, not anywhere

Let's say you create a menu with LPCM, that does not mean that you can just add mp2 audio to every video track, it is a violation of standards. But you can create a video track with 2/0 AC3 as one audio track, then 7 channel mpeg2 audio as another channel, which is inside the standard.

If an object is to have mpeg audio, the same object must also have either ac3 or LPCM audio.

Not arguing, just curious ...

The spec (as written) is a bit ambiguous then, because I would have interpreted it as somewhere (any track) you need DD or LPCM and any other track can have MP2, and not if you want MP2, that same track must have DD or LPCM. If it were to say each title must have DD or LPCM, then it would make more sense IMO.

Interesting ...

[disturbed1]

[The spec (as written) is a bit ambiguous then, because I would have interpreted it as somewhere (any track) you need DD or LPCM and any other track can have MP2, and not if you want MP2, that same track must have DD or LPCM.

Interesting ...

Then to quote your self,

One audio track must have DD or PCM Audio.

An audio track is inside the video track. The video track must have DD or PCM Audio if it is to have mpeg audio.

Try to create an NTSC project with Maestro or Scenarist. Maestro will warn you about it, Scenarist will fail on the build. The Maestro Manual and Scenarist manual have it pretty much cut and dry.

MPEG-1 Layer II Audio
For DVD product in PAL, MPEG-1 Layer II audio is compatible with all players. Note
however, that due to some vagaries in the DVD specification, most (but not all) DVD
players for NTSC markets (North America, Japan) support playback of MPEG-1 Layer II
audio. If you create NTSC titles using MPEG audio, be aware that there may be problems
in playback on some players.
If your application requires use of data-compressed audio with compatibility with all
players for NTSC, then we recommend use of AC-3 format. See the next section below for
information on encoding and authoring with AC-3 format audio.

Considering that most NTSC players are cheap junk (Sony, Apex, Cyberhome) they don't always follow the spec, and many can, and do get away with using MPEG audio. But when you get into distribution, you need to be 100% sure of the specs, there should never be guess work involved.

Specs aren't always true though either. Just like NTSC DVD supporting 7 channel mpeg2, out of my 8 personally owned DVD players, none support this format, though it was around before the DVD spec

[scottie78]

Then to quote your self,

One audio track must have DD or PCM Audio.

An audio track is inside the video track. The video track must have DD or PCM Audio if it is to have mpeg audio.

Cool

Thanks for clarifying that (for me, anyways)