Deinterlacing Question

[ajk]

Audio doesn't have a frame rate, it has a duration, i.e. how long it is.

If you have 60 minutes of video at 25 fps, and you slow that down to 23.976, your new video duration is about 62.5 minutes.

If you slow down the audio to 62.5 minutes as well, of course it is going to be slower, what else could possibly happen?

The only way to keep the original audio is to not do anything that changes the duration of your video.

[jagabo]

Most audio editors have the ability to change the audio duration with or without a pitch change.

[hizzy7]

Would audacity be good to fix the pitch? I could load clips of the audio so people could hear the difference, if you think it would help

[ajk]

@jagabo

Indeed, but the audio will still be slower (different tempo) whether the pitch is corrected for or not.

[jagabo]

@jagabo

Indeed, but the audio will still be slower (different tempo) whether the pitch is corrected for or not.

That's what I said -- "change the audio duration".

[jagabo]

Would audacity be good to fix the pitch?

Audacity has the ability to change the duration and the pitch, only the duration, or only the pitch. Most older PAL conversions were sped up to 25 fps with a pitch change because they were made by simply speeding up the projector. Hence the analog audio track was sped up by ~4 percent along with the frame rate resulting in about a semitone increase in pitch.

[ajk]

My point was that if duration is to be changed, the audio will sound different in one way or another. So hizzy7, you shouldn't expect the audio to sound the same after the processing, regardless of the settings you use.

[hizzy7]

so, does that mean that every pal/ntsc conversion will end up with weird sounding audio?

[ajk]

If it involves changing the duration of the video, yes. You only really notice it if you have the original to compare with, though - practically all films released in PAL video run with the 4% or so speedup, yet hardly anyone around here even notices it.

You can convert between PAL and NTSC in ways that don't change the duration, but then you need to drop or duplicate frames, and viewers spot uneven movement much more readily.

Of course if you are working on something that was film at first, then PAL video (with the 4% speedup), and you want it back to film speed, you are in fact bringing it back to the way it was originally.

[manono]

Sorry

[manono]

Is there a setting in Besweet that I can change?

No, BeSweet always changes the pitch. Haven't we been through this before?

It also sounded weird, perhaps slightly out of pitch, if that makes sense.

Yes, it changes the pitch. It was probably the source that was out of pitch and you fixed the pitch when you made it match the 23.976 video.

If you want to keep the pitch (which has nothing to do with your synch problem), you'll have to use a WAV editor, one such as Audacity.

However, before doing that has it occurred to you that it's the source that might be the one out of pitch and running the audio through BeSweet fixed it?

Edit: A lot of this was covered in the posts above. I got an email notification of the post that was the last one on the previous page and didn't notice a whole new page of replies.

[hizzy7]

Hi manono,

I think you are right. There are certainly issues with the source. Thank you all for your help. I will keep on trying to correct it & let you know how it works out!

h