I have a downloaded AVI at 29.97fps. Is it possible using TMPGEnc to perform an IVTC on this to bring it back to 23.976fps *and* speed it up to 25fps to make it PAL in the one encoding operation?
If so, where can I find a guide or steps for the settings to do this?
+ Reply to Thread
Results 1 to 5 of 5
Yes its possible. Just set the IVTC filter to 24fps. Then on the video tab set the output to 25fps and a PAL compliant resolution. Also make sure on the advanced tab to enable the "do not framerate conversion" filter. Now encode and this will take care of your video. Keep in mind though that not all footage can be IVTC'ed. If your source is pure interlaced or if it has undergone any strange conversions previously, then an IVTC will not work.
Don't forget that you will have to speed up your audio to match your video now. Use BeSweet. It has built in regional format conversion options. Just select the NTSC->PAL option.
Thanks for that. I'll give it a go. I have one more question about the audio though. I like GoldWave for converting the audio, but if I'm extracting the audio from the original 29.97 AVI and ultimately wanting to get it to 25fps, won't the pitch change considerably?
How can I get around that? I know how to go from 23.976 up to 25 no problem, but how do I deal with it when wanting to go from 29.97 to 25?
***Sorry about this. I've thought about it and I realise now that this is a stupid question. There is no difference in the play time between 29.97 & 23.976fps, so the conversion to PAL 25fps is the same procedure in either case. I already know how to do this.***
Originally Posted by adam
First off let me say something that I should have said from the start. There really is no point to what you are doing. Just about any PAL tv/dvd player combination will play NTSC just fine. I'd skip the conversion to PAL if your source is already adequate for burning, as it will only lower quality to do the conversion. As for something like a downloaded avi, well I suppose since you have to convert it to mpg anyway you might as well just throw in the regional conversion as well.
You are correct, 29.97fps and 23.976fps run at the same speed and in fact 23.976fps is always played back at 29.97fps on a tv anyway. Thus you'd treat audio conversions to and from NTSC equally regardless of whether you have NTSC or NTSCfilm.
As for checking your source to determine whether an IVTC is possible, load it in TMPGenc and use its preview function. Here you can scroll through your movie field by field. If every single frame is made up of two opposite fields, essentially you see nothing but interlacing, then your source is pure interlaced and an IVTC is not possible. If its any combination of progressive and interlaced frames, well than an IVTC may be possible and the quality of the result will be entirely dependant upon the accuracy of the IVTC algorithm. If you see three progressive frames for every 2 interlaced fields, well then your source has undergone a typical 2:3 telecine and it will be extremely easy to IVTC, and you can pretty much count on your output looking correct.
Basically, what you are looking for is a set pattern of progressive to interlaced fields. If this is present, and the pattern is constant throughout, than there is a decent chance an IVTC will work, and like I said a pattern of 2:3 is preferable.