Need help converting audio from PAL VCD and VHS to NTSC sources....

[qwertiio]

I have some of the movies that the dubbed audio I need which is available only on VCD (which is in PAL, 25FPS according to Mediainfo), and I want to convert those audio and mux it into movie files with proper frame rate that I have. (23.976 or 24)

the problem is, I've tried slowdown method with tools I could think of, like MeGUI, BeHappy, EAC3to, etc. but for some reason the output audio are still out of sync. even tempo change method via Audacity are also the same.

is there any method that, preferably, can be automate like the methods I've mentioned????? or there's no known way to do and that I have to manually sync it myself?????

[hello_hello]

You'll probably have to *try* to sync it yourself.
It's not unusual for the same movie from different sources to be edited slightly differently. Sometimes it's just one frame more or less on a scene change, but that only has to happen a couple of times to mess with the A/V sync even if the frame rates are the same.

[Alex_ander]

If you are lucky to have the video track's content in both sources exactly the same (frame by frame - check it in Avisynth, maybe at least long parts of it are the same), you only need frame rate numbers and audio processing tools with proper accuracy. Some of them, like 'time stretch' tool in audio editors like SoundForge give sufficient rounding errors. I use their resampling tool instead. If your target is DVD, you'll anyway need to resample your audio from 44,1 to 48 kHz. To correct the audio duration within this process, you first resample it to an adjusted sample rate, e. g. in case you go from 25 to 23,976 fps: instead of 48000 kHz you set the number 48000*25*1001/24*1000=50050 Hz. Then you go to 48000 with the checked option 'set frame rate only, no resampling' and this slows down your audio as needed. Then you'll only need to check manually a constant delay.

[hello_hello]

qwertiio,
I forgot to mention....

As you use seem to be an Avisynth user (at least via MeGUI) you could try the AudioSpeed() function in my signature.
That way you can open both the video and the audio you're converting in the same script and adjust the audio duration to see if they'll sync up, rather than having to keep converting the audio and mux it with the video in order to check it.

Obviously AudioSpeed() can do standard conversions between PAL, NTSC & film, but as you specify a numerator and denominator according to the amount of speedup/slowdown required, you're free to use whatever numbers you like if you think the audio needs to be stretched a little more, or a little less, than a standard amount. You can also apply a delay to the audio to at least make sure the A/V sync is correct at the beginning.

If you need to change the audio sample rate it's probably better not to use AudioSpeed for the actual conversion though, but only because it always outputs the original sample rate. To do that it has to resample the audio while stretching, and it'd be better to only resample once.