PAL -> NTSC Audio sync problem with TMPGEnc

[litlfrog]

Hi,

Posting my first thread here after a weekend of frustration. I've seen a lot of responses for something close to my problem, but nothing quite addresses it.

I've been learning how to convert PAL to NTSC over the past couple of weeks. I finally, FINALLY have converted an avi by extracting a wave with VirtualDub, transcoding the audio with BeSweet, and creating a new avi saved at 23.976 fps with VirtualDub. The resulting avi plays fine--no audio problems at all, and GSpot tells me that my file really is 23.976 frames per second.

The problem comes when I use TMPGEnc to convert it to an mpg so I can later burn an SVCD. I never get an error message or see anything wonky during conversion, but the resultant mpg always has slightly out of sync audio. I've been tearing out my sparse hair over this one. Why does my avi with audio in sync turn on me when converted to an mpg? Any help appreciated.

[sanjayk]

What settings did you use in TMPGEnc to create your SVCD file? You should select "Super VCD NTSC Film" template. This will enable "3:2 pulldown when playback" option for encoding.

[Bondiablo]

The simplest, most reliable, method I've found for PAL > NTSC is:

1. Convert the video only in TMPGEnc to 23.976 NTSC Film and check "Do not framerate conversion" on the Advanced Setting tab.
2. Demux the audio from the original video file using VirtualDub or TMPGEnc's MPEG Tools (depending on audio format)
3. Convert audio using Besweet and check the PAL>NTSC 25 to 23.976 option.
(4. Optional) Do a simple multiplex of your new audio and video in TMPGEnc's MPEG Tools. (If your authoring program doesn't accept elementary streams)

[litlfrog]

Hmm, I don't remember whether "3:2 pulldown" was checked or not; I'll try that this evening. Bondiablo, it hadn't occurred to me to convert the video using TMPGEnc and multiplex later. I'll give that a shot as well.

[Abond]

One even more simple and reliable way:
1.Convert the video to *x480 (NTSC resolution) at 25 fps in TMPG (use unlock template).
2. Apply dgpulldown for 25->29.97 pulldown.
3. Multiplex with original audio (or convert with besweet to suitable format - mp2 or ac3, but without framerate conversion!)

[jman98]

Litlfrog, you are going down a path that will almost certainly not give you very good results. TMPGenc is horrible for PAL-NTSC conversions. Even if you get the audio sync problem fixed, you may find that your video is not worth watching. People who are serious about this usually do one of two things.
1) Pay a fortune and buy Procoder to do the conversion for them.
2) Use AVI Synth scripts to do the conversion.

I haven't used it, but the suggestion to use dbpulldown (this is a relatively new program) may well be worth doing.

[Bondiablo]

TMPGEnc works just fine for PAL>NTSC. If you do it as described above, other than a slightly longer run time, you won't notice any difference between that video and if you had done it PAL. The only downside is you can't keep the original audio. When it sucks is if you try to keep the original run time and don't check the "do not framerate...", then the video gets jerky.

[litlfrog]

I must be doing something wrong, because I'm still having the same problem. To clarify:

1) When I use BeSweet to change the audio, I've been changing it to 23.976 fps. Is this correct, or should it be 29.97?
2) TMPGEnc's MPEG Tools apparently doesn't recognize wave sound, so I have to save the sound in another format (mp3, ac3, etc.) Are there any implications of this I should be aware of?
3) I find the phrasing "Do not framerate conversion" to be very confusing. Why would I want to check that if converting the framerate is precisely what I want to do?
4) I've selected "3:2 pulldown when playback"--correct?
5) Is it important what resolution/aspect ratio I choose? I've been using "Center (custom size) and entering the resolution of the original file from GSpot since TMPGEnc doesn't seem to have 1.74:1 as a default option.

Everyone's help is much appreciated. I don't want to quit when I feel like I'm close to getting this right.

[sanjayk]

In my opinion, the solution suggested by Abond should also have worked.

To start once again at the beginning.

Using VirtualDubMod extract the audio. Convert audio to MP2 (224 Kbps, 44.1 Khz) with HeadAC3he. Now create your AVI with VDubMod WITHOUT sound. Disable audio and select direct stream copy for video.

Use this AVI in TMPGEnc to encode only as ES. Select stream type as MPEG-2, framerate as 29.97 and encoding as Interlaced. You will get an M2V file.

Using "Simple Multiplex" in MPEG tools of TMPGEnc, mux this M2V file & MP2 audio file to MPEG file.

Hopefully this should solve your problem

[sanjayk]

BTW, the "Simple Multiplex" option in TMPGEnc does have LPCM (WAV) option for audio input but the audio will not be loaded.

[Bondiablo]

3) I find the phrasing "Do not framerate conversion" to be very confusing. Why would I want to check that if converting the framerate is precisely what I want to do?

without it tmpgenc will have to decide what frames to drop from the original video and that's when you get jerky play back. checking it keeps all the frames of the original file but the new file will have a frame rate (frames per second) of 23.976 instead of 25 which is why the new file ends up being a little longer than the original.

that's also why you have to run the audio through besweet, so the new audio matches the length of the new video. if you let tmpgenc do the audio it would stay the same length as the original and be out of sync with the new video, since audio deosn't have a frame rate.

[FulciLives]

extract the audio from the AVI using GOLDWAVE. Save it so you now have a 16-bit 48k Stereo PCM WAV audio file.

Load that audio file into BeSweet and do the "PAL 25fps ---> NTSC 23.976fps" option. Convert from WAV to WAV.

Now you can use BeSweet to convert the new WAV to the end sound format be is MP2 or AC-3. I suggest AC-3 at 192kbps, 224kbps or "best" try 256kbps (that is what I use).

The instructions on using TMPGEnc Plus (along with the DO NOT FRAME RATE CONVERSION) is correct as far as the video goes.

Be sure to use a BITRATE CALCULATOR to figure out your audio and video bitrates so that your end project fits on a DVD. Leave at least 100MB to 200MB so the MENU DESIGN etc. doesn't take up too much room.

DGPulldown works wonders though if you want to try that method.

- John "FulciLives" Coleman

[litlfrog]

Thanks very much for your help everyone--I've discovered that the problem must be deeper than I thought. ANY mpg I try to convert now has the audio out of sync. This is true even for simple NTSC avis of the type that I've made SVCDs from dozens of times. I tried reinstalling TMPGEnc, but the effects were the same. I'll try to fix it myself, and if I can't I'll start a new thread in the appropriate forum. Thanks again for your attention.