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brett63
04-08-2003, 05:21 PM
When creating a DVD using DVDWS, it allows me to select LPCM or MPEG as my audio type. Since this video came from a non-AC3 source (SA), I selected MPEG. It then displayed a message saying that it is a non-standard audio type. The disc plays fine on my Apex player, but has no audio on my friend's Sony.

If I choose LPCM instead, will DVDWS convert it to a compliant format when compiling the disc?
Alternatively, can I convert the audio to AC3 using BeSweet and mux it using TyMplex or TMPGEnc?

AlphaWolf
04-08-2003, 05:45 PM
You don't need to use besweet, tystudio can convert to AC3.

FreydNot
04-08-2003, 11:10 PM
I believe LPCM is an uncompressed PCM format (like WAV on windows). It should be avoided unless you are trying to fill your DVD full with audio data.

I always trancode to 2 channel AC3 audio when my target is a DVD. Most players will deal with mp2 audio, but its not in the official DVD spec (AC3 AKA dolby digital is part of the spec).

BubbleLamp
04-09-2003, 12:24 AM
Originally posted by FreydNot
I always trancode to 2 channel AC3 audio when my target is a DVD. Most players will deal with mp2 audio, but its not in the official DVD spec (AC3 AKA dolby digital is part of the spec).

Freyd, got a dumb question maybe, but do you add the MPEG video and AC3 audio as elemental streams to DVD WS, or do you remux the MPEG video with the AC3 audio before you load it into DVD WS?

Thanks

FreydNot
04-09-2003, 10:26 PM
Actuall, I make elemental streams and feel those to DVD Meastro. But same difference :)

brett63
04-10-2003, 12:02 PM
Thanks to all who responded. I will convert to AC3 from now on to ensure compliancy.

AFAIK, it shouldn't matter if you remux and import the muxed stream, or use elemental streams in your DVD authoring program. If you can use the elementals, great. One less step to worry about. In my case, I need to edit out commercials and therefore need to remux before editing.

jmhenry5150
06-26-2003, 11:09 PM
Hey brett63,

What was the final resolution to this?

I also have a Sony and it does not like MPEG II audio - only Dolby Digital...

Did you figure out an easy way to get these to play on the Sony?

Thanks!


-Mike

brett63
06-27-2003, 09:50 PM
I ended up using tyStudio to process the audio. It has an excellent transcoding engine that converted it to 2 channel 48k AC3 @ 192 kbps.

Besweet does a great job as well, but to use it you have to first split the streams, convert and then remux. I wrote a batch file to leverage the tyProcess executable to do the conversion in a single step.

I'm sure that Josh's update will yield similar results.

jmhenry5150
06-27-2003, 11:43 PM
Interesting!

Now for a really stupid question (as I am used to tytools doing everything for me)

What exactly do I do with the MPEG files after TyStudio is done with them?

-Mike

captain_video
06-28-2003, 06:52 AM
That depends on whether you created mpeg files or split them into elemental streams. Using a compatible authoring program, you can import the elemental streams (SpruceUp & DVD Maestro) or the mpegs (DVD Movie Factory & DVD Workshop) and create a compilation that can be burned to DVD. You can add menus with graphics and add chapter stops to make it easier to navigate throught he disc. This is what the whole extraction process is all about. The end result of extraction is to be able to copy your favorite shows to DVD and play them back on a set top player.

For those of you having problems getting your DVDs to play in a Sony, I'd recommend getting a newer model. I have a Sony DVP-NS715P and it does a great job of playing my ty DVDs without a problem (the vast majority of them have mpeg layer II audio).

raj2001
06-29-2003, 12:44 PM
Originally posted by jmhenry5150
Hey brett63,

What was the final resolution to this?

I also have a Sony and it does not like MPEG II audio - only Dolby Digital...

Did you figure out an easy way to get these to play on the Sony?

Thanks!


-Mike

The strange thing is that my Sony PS2 doesn't seem to have a problem with the MPEG2 audio...

jmhenry5150
07-01-2003, 08:53 AM
brett63 -

Can you share your workflow as well as the batch process that you have?

I'm considering buying a new SONY DVD player - but I would like to try other options first...

-Mike

jmhenry5150
07-01-2003, 09:37 AM
captain_video -

Can you confirm, once again, that the SONY DVP-NS715P plays TyDVD's that have MPEG II audio?

I think I will bit the bullet and sell the DVP-NS700P and upgrade - but before I do it, I need a little hand holding :)

BTW - I will be using TyTools to create my TyDVD's...

Thanks!

-Mike

Hi8
07-01-2003, 12:50 PM
Originally posted by jmhenry5150
captain_video -

Can you confirm, once again, that the SONY DVP-NS715P plays TyDVD's that have MPEG II audio?

I think I will bit the bullet and sell the DVP-NS700P and upgrade - but before I do it, I need a little hand holding :)

BTW - I will be using TyTools to create my TyDVD's...

Thanks!

-Mike

I can confirm that, mine plays TyTool_DVD's fine.

brett63
07-01-2003, 01:05 PM
Mike,

Here is what I am doing right now:
1. Extract video using TyTool7R3: VSplit mode, Patch Audio Holes.

2. Use tyStudio tools (tyTranscode, tyMplex) to convert audio to
AC3 and multiplex into single MPEG file (see batch file below).

3. Edit commercials using MPEG2VCR.

4. Create DVD with DVD Workshop.

Now, here is why I do it this way:
1. I use TyTool instead of TyStudio because it doesn't require me to install an indexing daemon on the TiVo. Hopefully future versions will allow me to disable the resource-hungry TiVo side editing feature.

2. tyStudio gives a nifty console for doing all types of processing, but it takes a couple of minutes to load each file (creates a frame index). This wouldn't be a big deal if I was using it to edit, but I'm not. So, I wrote 2 batch files to process the stuff:

File #1: process.bat
if exist "%~dpn1.mpg" goto end
"C:\Program Files\tyStudio\typrocess.exe" -iv %1 -ia "%~dpn1.m2a" -o "%~dpn1.mpg" -mplex { -f 8 } -demux -tcode { -b 192000 -s 48000 -a }
:end

File #2: allfiles.bat
for %%1 in (c:\mpegsrc\*.m2v) do call c:\temp\process.bat "%%1"

To process all of the files in my source directory (c:\mpegsrc), I just double-click on the allfiles.bat file. To process a single file, I drag and drop the .m2v on the process.bat file.

3. What can I say? I'm a sucker for frame-accurate editing. MPEG2VCR does this very well.

4. My streams are already 720x480 (SA), so no need to patch the header. Pr.Sinister created an excellent Flash demo on using DVD Workshop. Always worked well for me.

My suggestion would be to wait until the next release of TyTool before tossing away your DVD player. Audio is relatively simple to fix, compared to video issues. There are several ways to accomplish the results you want, depending on what tools you have access to.

jmhenry5150
07-01-2003, 01:45 PM
brett63 -

WOW! that's alot of steps...

Also, how time consuming is this? If it's a huge difference - I have no problem getting the new player...

On another note, can you change the header for the audio like you can the video?

I know I can fool this player into playing an SVCD when it really isn't supposed to...I wonder if you can do the same thing here for the audio...

Thanks!

-Mike

brett63
07-01-2003, 06:21 PM
WOW! that's alot of steps...

4 steps is a lot? I beg to differ, since I have seen my fair share of 6+ step processes out there.

TyTool7, for example (IMHO an excellent stand-alone solution) requires the following steps:

1. extract the video from your TiVo
2. create a key file.
3. edit the file using GOPEditor.
4. VOB-Mux the file.
5. author the DVD (create IFO files)

Hopefully, the next version will have the AC3 conversion built in, to avoid another step.

Is my process time consuming? Yes, I would say that it is, mainly since I am reprocessing the muxed output through MPEG2VCR. This is certainly not necessary, but I strive for frame-accurate editing, whereas others may be perfectly happy with GOP-accurate editing. Also, DVDWS is very slow in processing the files, but I really like it's menu template capabilities.

jmhenry5150
07-01-2003, 06:29 PM
Mabye it just seemed like alot...

Sorry, didn't mean to offend...

Anyways - how long does it take to process an hour file?

Pro-289
07-01-2003, 06:58 PM
Originally posted by brett63
Is my process time consuming? Yes, I would say that it is, mainly since I am reprocessing the muxed output through MPEG2VCR. This is certainly not necessary, but I strive for frame-accurate editing, whereas others may be perfectly happy with GOP-accurate editing.
brett, does MPEG2VCR reduce your video quality noticeably? Does it affect the rest of the video that you aren't cutting & pasting? Is there any method of frame accurate cutting without recompressing?

brett63
07-01-2003, 07:31 PM
Pro-289:
MPEG2VCR only re-encodes the areas around the cutpoints, to rebuild the frames before and after the cut. AFAIK, there is no quality loss.

jmhenry5150:
No offense taken. Just wanted to give you a baseline of what is involved with virtually any solution. I certainly didn't pick the simplest method, but it delivers the results I want.

I have a fairly fast machine with a fairly slow hard drive, and I think it takes around 10 minutes to save a file in MPEG2VCR, depending on how many cuts it has to process.

The tyStudio audio conversion and remux takes about 5-10 minutes per file as well. All things considered, not a seriously long time to wait, but a little interruptive. To get around this, I try to batch together as much work as possible (thus, my batch files), and find something else to do while it processes.

jmhenry5150
07-02-2003, 08:20 AM
Well, this is mabye a moot point now...the new version of TyTools coverts MPEG II audio to AC3...awesome!

I made a test disc of a 30 minute episode of Seinfeld last night - and it worked!!!

One caveate is that the chapter stops did not work well, it would move to the next chapter and pause. The only way to unpause it is to use the >>| button...weird...

Anyways, give this tool a try - it works...

-Mike