"The rule is to always try to keep DVDA happy, and it is happier with separate audio and video streams"

And that is what I have always done and did for both DVDs.
One plays fine, the other doesn't. Only difference is one had "Include audio" enabled in the mpeg-2 encoder settings and that's the one without the problem.

Bob.

In your DVDA project,
which audio track is listed under TRACK MEDIA?

I am confused, is it the one with MPEG2 audio that won't play?

DVDA will include the audio muxed with file if it exists unless you change it.

Dave T2

"which audio track is listed under TRACK MEDIA"

Not sure, will have to go have a look.

"I am confused, is it the one with MPEG2 audio that won't play?"

NO, that is the one that plays fine on both players.

"DVDA will include the audio muxed with file if it exists unless you change it."

I know, authored around 1,000 DVDs, including a few that have been sold in shops.

----------------------------------------------------------------------------------------------------------------

It seems to me the situation is this.

Include audio in the mpeg-2 encode and DVDA leaves that as is as, in the vision stream. It then also muxes in the audio from the audio track. Conventional DVD players will ignore the audio muxed into the mpeg-2 vision stream.

However there are ways to play the mpeg-2 stream that will also use the audio stream muxed into that. If that's not there even though the other audio stream, the one DVDA muxed in, is, THEN no sound.

Bob.

From the sounds of it, whatever DVDA encoded the WAV in to on the one DVD doesn't have a supported codec on those specific playback computers. It's either AC3 or WAV as far as I know.

I've always just rendered out my ac3 file and didn't let DVDA do anything but menus/etc., but that's what comes to mind.

Bob,

Sorry, wasn't trying to question your knowledge. Just trying to figure out the problem.

You made an MPEG file with MPEG audio. Brought that into DVDA and then added a SECOND audio track, is that right, or did you replace the MPEG audio track with another track?

I would agree with Happyfriar that it is probably a missing codec.

Dave T2

I've long since regarded DVDA as nothing more than a very VERY capable graphics package. I won't allow it to do something to the audio or video. I prepare EVERYTHING exo-DVDA. Maybe an additional WAV file, not linked to any video? But the thought of a WMV stream? Just plain ole MPEG2 and AC3 here. Just 'cos it says it will, I don't allow it to. I'm not clever enough to go fiddling under the bonnet.

Grazie

little thing: AFAIK, mpeg audio its "not allowed" (out of specs) for NTSC DVDs, only PAL can have it.

Some more info back from the client:

In all PCs the DVD opens at the root menu. So all players are seeing both DVDs as DVDs, not simply playing files off the DVD. On several PCs, seemingly ones with Vista or Win 7 play out the movie with audio, the ones with XP play vision with no audio.

Yes on both DVDs vision was encoded out of Vegas as mpeg-2 and audio encoded as PCM (.wav) 16/48KHz as I've done many times. DVDA was not left to do any encoding.

One curious thing I remember. When it came to author the first DVD, the one that works in all PCs, DVDA threw a warning that the audio would need to be re-encoded. It hadn't loaded the PCM file as the audio track. I quickly forced it to do that. I suspect DVDA had seen the audio stream in the mpeg-2 vision file and was going to use that.

My conclusion is that one should always include the audio when encoding to mpeg-2 for DVD. It would seem that DVDA does not replace that stream. It will mux in an additional audio stream, either PCM or Dolby. Some PC based players it seems will only read the audio stream inside the mpeg-2 video stream. This almost certainly is a bug in the player itself, one that's seemingly fixed in later versions of Windows Media Player. Of course trying to explain that to a client who's a manager of a large retail chain, well good luck...

Bob.

Well analysed Bob. As to explaining to a manager? Isn't kind too late?

Grazie

"As to explaining to a manager? Isn't kind too late?"

By several decades :)

After a geriatric's nap I realised I've been thinking of what's on a DVD, in particular what's inside a VOB way too simply. It's way more than a elemental stream, it's a Program Stream.

I will not pretend to understand all that but I get enough of it to say many things are possible and in concert with what half baked players might do there's an ocean of pain waiting to wake us from a sleep of blissfull ignorance.

Bob.

Malowz,

In NTSC, MPEG audio is not a DVD standard. It is hit or miss if it will play. Some DVD players will play the audio. Especially the earlier players that were designed to play VCDs and such.

I never include the mpeg audio when I render. It definitely would render as a program stream, but I always assumed that DVDA would demux it and replace it with the TRACK MEDIA selected stream.

Dave T2

Made a new set of DVDs for the client, this time with the Include Audio box checked in the mpeg-2 encoder. Authored as per usual with PCM audio track. DVD plays in all PCs. .

Bob.

Hmmmm, maybe i'm missing a point here, but ... since the standard procedure is to render an MPEG video file with no audio included, and render a separate audio file, AND since the standard DVDA templates are already set up this way, AND this always works ... why would you do anything different?

"Hmmmm, maybe i'm missing a point here, but ... since the standard procedure is to render an MPEG video file with no audio included, and render a separate audio file, AND since the standard DVDA templates are already set up this way, AND this always works ... why would you do anything different?"

Because it doesn't "always work".

Including the audio in the mpeg-2 encode means it does "always work"

It seems the audio included with the mpeg-2 stream is not replaced by DVDA, it just gets left there. The specified audio track is also added into the stream. that is what gets played by almost all possible players but not some, they only playout the stream encoded by Vegas into the mpeg-2 vision stream.

For me really quite confounding TBH, not like I haven't been making DVDs for around a decade and this is the first time I've had this issue. It's not isolated either, my client checked on several PCs, some play the audio some don't. They also checked out their clients PCs, same result.

Bob.

ps If I can I'll check this out further by using different audio for the mpeg-2 encoding and the PCM audio file that DVDA will mux in.

what problems DVDA mpeg + separated ac3 audio has caused?

"what problems DVDA mpeg + separated ac3 audio has caused?"

Haven't tested that. Only (DVDA mpeg +/- audio) + separated PCM audio.

Although out of the box some PC based players will not play ac3 anyway, need to pay for Dolby licence.

Bob.

well, you could always include media player classic in the dvd, with autorun. will play directly if the pc has not disabled autorun

MPC has all the decoders buillt-in. or/also include instructions on how to use it ;)

Dave T2 is right. MPEG audio is only valid on PAL format DVD's. For NTSC you must use either Dolby Digital (AC3), or PCM (Wave) Audio formats.

The problem is that some NTSC DVD players will recognize MPEG-2 audio, and others won't. But according to the DVD spec, NTSC players are not required to play MPEG audio. It's best to stick with the spec if you want to guarantee that your DVD Title can play on everything.

"It's best to stick with the spec if you want to guarantee that your DVD Title can play on everything. "

How is anything that I've said implying not sticking to the spec?

Wether or nor MPEG audio is part of the spec is irrelevant.
The DVDs I've made, the ones that play on everything, include a stream of PCM audio which IS part of the specification.They (apparently) also include an unreferenced stream of mpeg-1 layer 2 audio. Because that stream of audio is unreferenced a STB DVD player will never see it or attempt to play it. It will play the referenced stream of PCM audio.

Bob.

I've just run a quick test using DVDA 5.2.

In Vegas I created a 5 minute test pattern.
I added an audio track of music of the same length.

I rendered it as an m2v + a wav.
I rendered it as an mpg with mpeg audio 224kbps (PS).

In DVDA I :
(1) added the m2v with the wav audio track.
(2) added the mpg and replaced the audio with the wav.

I prepared the DVD and looked in the Video_TS folder.
There are two VOBs of identical size. Mediainfo reports them both as having only one audio stream, and it is a PCM stream.

I know this doesn't solve your problem, but I don't see how there can be any mpeg audio in there if the VOB sizes are the same.

I have produced over 200 DVD projects over the last 10 years that have been for world-wide distribution, I used to make the NTSC DVDs using AC3 audio and the PAL format discs using MP2 audio. About 3 or 4 years ago, I started making all discs using AC3 audio and have since sold thousands of discs with no playback compatibility complaints whatsoever.

"I know this doesn't solve your problem"

Well my problem is solved. The only "problem" remaining is how does what I did fix it.

"I don't see how there can be any mpeg audio in there if the VOB sizes are the same."

I can. The mpeg-2 encoder's bit budget includes the audio stream. So when I encoded the mpeg-2 video at 8Mbps the actual video bitrate is 7,776,000bps.
That's arguably a good reason not to include the audio especially when encoding at low bitrates.

Bob.