[FFmpeg-user] Keeping A/V sync during telecine

Carl Zwanzig cpz at tuunq.com
Sun Dec 31 19:23:18 EET 2017

On 12/31/2017 7:28 AM, Eric Wilde wrote:
> Telecine, in my opinion, was just somebody's misguided attempt to
> turn film into video, with a standard frame rate.  Maybe at the
> time, it was necessary. 

No maybe involved. Up into the 1970s, and probably later*, content produced 
for TV was produced on 24fps film and delivered to the stations that way (as 
were all movies). If you wanted to show this in an NTSC country, it was 
telecined live to the transmission chain. Worked well enough for the purpose.

*until the advent of readily usable video editing systems; A/B roll does not 
count as one.

> But, given that video players seem to be perfectly capable of switching
> frame rates on the fly, a rather pointless exercise.
That is if you're using one of those rate-agile players. There are both NTSC 
analog and fixed frame-rate digital systems out there.

> Not to mention a complete pain for anyone who
> is trying to "fix" such a video at this moment in time.

Which is why you convert only what you need and _keep_ all the originals 
(which I think should be obvious). Anyone trying to de-telecine when the 
originals are available is on a fool's errand.


who, just once, did some insert edits on 2" video tape

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