[RESOLVED] 29.97 IVTC to 25 help needed

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Re: 29.97 IVTC to 25 help needed

Post by admin » Fri Jul 11, 2014 6:36 am

To help you I will need to see an unprocessed source sample. I don't know VideoRedo well enough to understand or trust the information you gave. There are three ways to get the sample, your choice:

1. You can cut it with DGSplit.

2. Open in DGDecNV, set a range and do Output Trimmed TS.

3. Open in DGDecNV, set a range and do Save project and demux video. Then give us the resulting M2V file.

In any case, upload somewhere, then post the link here. 50-100 MB of a scene with a lot of motion will be good.

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Re: 29.97 IVTC to 25 help needed

Post by admin » Fri Jul 11, 2014 8:56 pm

It was hard telecined from 25 to 30 fps and then slowed down to 29.97 for NTSC compliance.

You can do this:

telecide()
decimate(6)

It gives smooth motion for your sample. Because you'll probably want a standard PAL rate instead of 24.975, you'll have to add this at the end:

assumefps(25.0)

Then, to keep AV sync you'll have to change the audio as well.

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Re: [RESOLVED] 29.97 IVTC to 25 help needed

Post by Aleron Ives » Sat Jul 12, 2014 1:44 am

Wouldn't you also want guide=3 on Telecide to enable PAL -> NTSC pattern guidance? I doubt blind matching would do a noticeably worse job, but since you went to the trouble of implementing that functionality, I'd say we ought to take advantage of it... :D

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Re: [RESOLVED] 29.97 IVTC to 25 help needed

Post by admin » Sat Jul 12, 2014 2:14 am

Sure you can use pattern guidance. I forgot about that. :o

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Re: 29.97 IVTC to 25 help needed

Post by admin » Sat Jul 12, 2014 6:52 am

MrVideo wrote:what about the 4-3 pattern, which involves 7 frames?
I didn't see anything like that in your sample. After field matching all I ever see in your sample is 5 unique frames and 1 duplicate which is exactly what you expect for 25->30 pulldown. To be honest, I don't even know what you mean by 4-2 and 3-3. Can you please point it out in the sample?

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Re: 29.97 IVTC to 25 help needed

Post by Aleron Ives » Sat Jul 12, 2014 5:34 pm

MrVideo wrote:Unfortunately it will have to stay at 24.975. There are two audio tracks, the main one being Dolby TrueHD 5.1. I have no means to deal with the audio.
I wouldn't say that, since IIRC ffmpeg can decode TrueHD tracks. You'll get a WAV file which you can then speed up with your audio tool of choice, and then you can either encode to FLAC or go the lossy route with AAC or some other codec. Using FLAC might be a little deceptive, though, since by modifying the audio to speed it up, it is technically no longer lossless.

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Re: [RESOLVED] 29.97 IVTC to 25 help needed

Post by admin » Sat Jul 12, 2014 10:06 pm

24.975 is not a legal bluray frame rate.

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Re: [RESOLVED] 29.97 IVTC to 25 help needed

Post by Aleron Ives » Sun Jul 13, 2014 2:03 am

The BDMV standard has many arbitrary and sub-optimal limitations. If your player supports videos in other containers, even if they don't conform to the video stream limitations enforced by BDMV, then you might as well target another container. My LG Blu-ray player, for instance, allows H.264 in MKV with a 10-second GOP and > 3 consecutive B-frames, even though both things would violate the BDMV specifications if I tried to use M2TS with the BDMV file and folder structure.

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