AC3 to AC3 (NTSC to PAL)

[mjthriller100]

I have an AC3 audio which is in NTSC format (23 fps or something like that). I want to convert it to 25 fps so it will stay in sync with my video. The original audio is perfect (no problems). I used AC3 Machine to convert but the output of the audio had some crackly sounds (hope that makes sense) especially in the high bass areas.

What do i need to do to convert NTSC to PAL without effecting the quality.
THANK YOU

[Cornucopia]

Don't get sidetracked with misinformation.

AC3 (or any audio) isn't "NTSC" or "PAL". Only Video is.

How you converted your video determines what you might need to do with your audio.

1. Interpolating frames-type conversion. Won't change the actual length.
With this, you don't need to do anything to the audio.

2. Re-assigning frames ("Stretching")-type conversion. WILL change the length.
With this, you'll need to decode the AC3 to WAV, Use Time-compression/expansion to match the length of the video, and then re-encode to AC3.

#1 is the preferred method, even though the result includes blended frames.

Scott

[SoCalMK]

Is your audio file 5.1 or not?

[SoCalMK]

Sometimes when a 5.1 audio file is converted to wave or a non 5.1 AC-3 file, the resulting file will include the crackling noise that you have described. If it is a 5.1 file, make sure that you are keeping it at 5.1 when changing the fps and the distortion should go away.

[mjthriller100]

thanks for the quick replies
what i do is extract the AC3 from the avi (how do i found out if it is 5.1ch). Then i use AC3 machine to convert NTSC to PAL. When i input the audio into TMPGEnc DVD Author it says the sound is 6ch or something like that. Is this correct?
THANK YOU for all the help

[SoCalMK]

Here is a quote from FulciLives, who was helping me convert a PAL DVD to NTSC:

"IF the PAL is 5.1 AC-3 then you don't want to do the above. You want to use AC3Machine instead as your front end to BeSweet instead of the BeSweet GUI and you want to convert direct from the original 5.1 AC-3 to a new 5.1 AC-3 using the FPS conversion. For the FPS conversion you would type in 25000 to 23976 and make sure that you have none of the AZID stuff checkmarked and make sure you have CHANNELS MODE set to 5.1 and make sure you use 448 for the bitrate. Also set the delay etc. I don't use any of the gain or dynamic compression options etc. when doing this."

And if TDA is telling you the audio is 6 channels, that should be an indication that it is a 5.1 file.

[mjthriller100]

thanks for the reply SoCalMK but i don't understand from your post what i need to do.
here is some more info about my audio:
48000Hz
channels - 2 (stereo)
192 KBs

I should have mentioned that the audio i input into TMPGEnc DVD Author is the converted one, not the original. When i input the original audio the input format is Dolby Digital (AC-3) 48000Hz 192kbps. And it gives me the option to choose stereo 2 channel or bilingual 2 channel
THANK YOU

[Abond]

Well then, is your AC3 5.1 or 2.0?

[aguillon]

Looks like your audio is 2 channel - Have you tried using the FilmMachine?

This all in one encoder is really good at doing NTSC to PAL and PAL to NTSC conversions (it s basicalle a Besweet front end).

As a bonus, it can use external encoders like CCE or Procoder for video encoding.

Used it a few times with great results on Xvid/Divx to DVD conversions.

Cheers

[mjthriller100]

Thanks for the replies
sorry for the delay
I think my audio is 2.0
"aguillon" does the "FilmMachine" convert audio or only video files.

Please any suggestions on how to solve my problem would be appreciated and if more info is needed then please reply
THANK YOU