LPCM or MPEG Layer 2

[garvey100]

Hi guys
I am having a few problems currently with the audio when encoding. It's nothing to do with it sounding dodgy, its just that as lpcm is uncompressed, its taking up too much room and the video is having to be compressed so I can fit what I am doing on a single 4.7 gig dvdr.
Here is the process I use for vcd (which is what I am encoding)
1 TMPGENC to cut and merge the 2 files
2 I then main concept mpeg encoder - this is where I am confused. I was told by a friend that if I am encoding ntsc that I have to use lpcm audio....is this correct? I live in a pal region but obviously encode ntsc-ntsc as the frame rate is far superior. Question is, can I use layer 2 compressed audio instead of lpcm with an ntsc encode as at the moment I am shrinking the video once I have compliant files and am losing a helluva lot of quality.
Any help gratefully appreciated.

[daamon]

Hi garvey100,

I'm not gonna answer your question directly as I'm not entirely sure with NTSC (I live in PAL land too).

What I do know is that NTSC players don't play MP2 audio, whereas European ones do.

EDIT - On reflection, what I suppose I meant is what andkiich said in his opening line (a few posts down).

That said, if you've a European player and mux NTSC video with MP2 audio - I don't know if there'll be issues there. Give it a go on a rewriteable and see... (That's why I've not answered your question directly).

However, there is still light at the end of the tunnel. Take your PCM audio and use ffmpeggui to convert to AC3 (it does MP2 too, and is MUCH simpler than BeSweet for simple encodes) - this is comparable to MP2 in terms of final file size and quality. Encode at 192 - 256 kbps from a good source.

Then use the AC3 in place of the PCM - hopefully achieving what you want.

Hope that helps. Good luck...

[SLK001]

MPEG layer II files? What's that? Do you mean MPEG 1, Layer II audio? Or do you mean MPEG 2 audio?

The most compliant audio types are LPCM and AC3, then MPEG 1, Layer II (.MPA extention). MP2 audio is not part of the NTSC DVD spec so may not play in many players.

Get yourself an AC3 encoder and try using that format.

[andkiich]

MPEG1 Layer 2 audio is not an official part fo the NTSC DVD standard, however, I have not found a machien yet that does nto play them.

One thing that you might notice though, is that MPEG1L2 audio has a tendency to be a lot louder and can introduce distortion on some audio systems.

There are a lot of free audio encoders that will take LPCM audio and convert them to AC3(Besweet, etc.).

If you want to be 100% NTSC DVD compliant, then use either LPCM or AC3 audio.

[tigerman8u]

I use mpeg1 layer2 for all my encodes and haven't had any problems yet.

[garvey100]

Right....i tried layer 2 and had some quite serious synching issues with the audio so i am trying ac3 instead........what do i do.......do i demultiplex with tmpgenc and then convert audio and then remultiplex?

[FOO]

There are a lot of free audio encoders that will take LPCM audio and convert them to AC3

I would be very interested to see that list of a LOT of encoders.

[garvey100]

I would also be interested to see what relevance your post has whatsoever to the topic in question???
No offence intended!

[garvey100]

and the other thing is.......do i do convert lpcm to ac3 before or after i make the dvd compliant file with my encoder

[andkiich]

Don't mind FOO, that's just the way he is.

What you do with the AC3 audio after you have it depends on what you're doing next. TMPGEN doesn't play well with AC3, so after that it's probably going to fall onto the lap of an authoring program.

Find one that will work with AC3 files and you should be all set.

[garvey100]

Thx for the vote of confidence!
What I was thinking of doing was getting the dvd complaint files using main concept mpeg encoder first, and encoding to lpcm,then demuxing and converting to ac3 and then remuxing using tmpgenc and then using tmpgenc dvd author to author the lot..............would that work....if not.....what authoring prog would u recommend?

[dun4cheap]

Just curious if it was mpeg2 audio causing the audio sync problem. I currently have been using Studio 8 to edit my daughters cheer team videos. I have constructed a full dvd using studio 8, menus and all about 79 minutes worth. I opted to use mpeg2 audio to gain more space for the video. I would love to go to AC3 but Studio 8 does not offer it, but studio 9 may in the future. My audio has played perfectly in sony dvd player, panasonic, apex, daewoo and toshiba players without sync problems. Are you possibly having a sync issue with your DVD Authoring Tool?

If you do find an AC3 solution please share, the besweat direction does not seem like a good solution. I did notice that the recent release of Tmpeg DVD Authoer now has an AC3 pluggin maybe something in that direction. But Studio 8 lets me have introduction video before my menus, It also lets me create custom animated buttons and place them anywhere on the screen, hard to give all that up. Well good luck, I hope you find an AC3 solution.

[garvey100]

I will certainly let you know what happens......I tried to use layer 2 audio with ntsc on main concept mpeg convert.....i am now trying to do the audio separate........and then remuxing using tmpgenc.....if that doesnt work then i may well try tmpgenc plus to do the layer 2 audio with ntsc to see what happens.....
that is the joy of re writable discs!!!! 8)

[dun4cheap]

Can you create the dvd files on your hard drive and play it with Power DVD. Does the audio sync problem show only on external DVD players? I was having audio sync problems working with mpg2 files in studio 8. So I made one large DV Avi file and then authored my dvd in studio. Added all my menus and all and created the DVD file structure. My audio sync problems went away. It had something to do with the muxing and encoding of the mpeg2 file from an mpeg file.

[garvey100]

Unfortunately the synch probs show on the hard drive as well once i have re encoded using main concept as well as stansalone........ i am not sure whether main concept is to blame (it seems such a good prog) but tmpgenc seems to accept the merging of layer 2 and ntsc more readily............will let you know. I think spending the time coding the audio then remuxing might be my best bet by the looks of things.

[thayne]

What I do know is that NTSC players don't play MP2 audio

Nonsense! I have never seen an NTSC dvd player that cannot play mp2 audio.....

[daamon]

What I do know is that NTSC players don't play MP2 audio

Nonsense! I have never seen an NTSC dvd player that cannot play mp2 audio.....

Check out my edit Thayne - before you posted. You gotta be quicker than that...

[daamon]

and then using tmpgenc dvd author to author the lot..............would that work

When creating the chapter points in TMPGEnc DVD Author, you can play the project, but TDA doesn't play the audio if it's in AC3. However, once all's created and you burn to DVD the audio comes out fine. AC3 just kinda "passes through" TDA.

I believe that the latest version of TDA does / will have AC3 support.

[Nelson37]

SFAIK, MP2 audio is not standard for NTSC DVD but it will play in most players.

BeSweet seems to work best encoding to AC3 from a WAV file, I ruined the entire set of Band of Brothers trying to encode from Mpeg audio, sound was garbled. Same source encoding from WAV was fine. Of course I had already deleted 7 of the 9 original captures, lesson learned.

I use Sonic MyDVD to author and burn the files muxed in TmpGenc, it doesn't have much flexibility but accepts these files just fine.

There have been several posts about a specific brand of player that doesn't like BeSweet AC3, Panasonic or Pioneer I believe.

[dun4cheap]

Well I did run into a 2 year old Sony dvd player that wouldn't play the mp2 audio, but I am willing to take the risk. I have tested my final cheer dvd in about 10 players and the one old sony played the video but know audio. It does play in my combo sony dvd/vcr combo. As for conversion tool and technology, I am sure we will see a one click solution for AC3 conversion within 6 months. Way to many talented people on this web page for this not to happen. I have alrady requested the SDK from pinnacle for studio 9 inorder to research creating an AC3 plugin for it. I would love nothing more than to be able to shell it with the Tmpeg DVD AC3 plugin...

[mrlewp]

MPEG2>>>Audio Sync ;
I can have a synced mpg2 (DVD compliant) file , looks and sounds good, with all editing done. But if I prepare for burn , by adding chapters, thats where I then get sync problem. (either on burned disc , or "saved to HD" as .vob set)

Opinions about best usage of drives , and defrag...as these are two points brought up in audio/video sync discussions;

When I defrag, any .vob files are left untouched, as are .mpg files that approach 1G size...even tho' there is plenty of free space on the drive.

Re: drive usage. Way back I thought that it would be best to have files ready to burn on 2nd drive, to free up primary drive where burn program runs from. Agree?? Now, I wonder about that "Temp" folder that many programs need to write to. Would that be the more important part of this process , IF it is the location of burn app.s final "ready for burn" files. Confused about this. Reply may differ as to whether beginning with an .mpeg movie file , or prepared set of .vob files. ??

[bugster]

@mrlewp, if you have a question, please start a new topic rather than dredging up an old and only partly related one.

/moderator bugster