Standards Conversion 24fps to 29.97

Get answers to your questions about color grading, editing and finishing with DaVinci Resolve.
  • Author
  • Message
Offline

jamesharding

  • Posts: 16
  • Joined: Sat Dec 07, 2013 3:54 pm

Standards Conversion 24fps to 29.97

PostMon Mar 20, 2017 3:36 pm

Hi all,

In other NLE's, when I want to take a clip at a different frame rate and conform it to the frame rate I am working at, I will interpret the clip as a different frame rate, causing it to slow down or speed up both the video and sound. This way I do not have issues with drop frames, only sped up video and higher pitched sound.

In Resolve 12.5 (or my setup at least), when I do interpret the clip at another frame rate, it will do two things.

1. in the media pool, it will not change the speed of the clip and the sound will stutter as if resampled
2. In the timeline, the video will be sped up or down to match timeline frame rate, but the audio will be kept at the same speed. The audio will then drift out of sync.

How do I get Resolve to speed up the sound and video at the same time? I do not want to manually respeed the clip as I do not want the clip to drop frames or have frames emulated, nor the sound destroyed.

Thanks,

James
Offline

Andrew Kolakowski

  • Posts: 2154
  • Joined: Tue Sep 11, 2012 10:20 am

Re: Standards Conversion 24fps to 29.97

PostMon Mar 20, 2017 3:45 pm

It's actually bit tricky.
24p needs to be slowed down to 23.976p (so there is 0.1% speed change) and then you add 3:2 pulldown which will make your clip 29.97i. Note- your final clip has to be treated as interlaced.

The only other way is to use motion adaptive frame rate conversion which is expensive (Alchemist, Tachyon) and depending on the source nature may end up well or not.

Next time: avoid mixed fps- this is real issue which is not easy to deal with. Only same time based fps are easy to cross-convert e.g. 25p/50p or 30p/60p etc.

In Resolve- assume fps as 23.976p for your source clip and export as 29.97i with 3:2 pulldown. Check if audio stays in sync at the end (not sure how Resolve deals with such a conversion).
Offline

jamesharding

  • Posts: 16
  • Joined: Sat Dec 07, 2013 3:54 pm

Re: Standards Conversion 24fps to 29.97

PostMon Mar 20, 2017 3:49 pm

Hi Andrew,

Thanks for your reply, I should have been more clear that 24 to 29.97 I just used as an example. In a progressive timeline, if I were to similarly go between 24fps and 25fps, I would expect Resolve to slow down or speed up the video and audio to match the timeline frame-rate without any pulldown, frame blend or motion estimation. Can it do that?

Thanks

James
Offline

Andrew Kolakowski

  • Posts: 2154
  • Joined: Tue Sep 11, 2012 10:20 am

Re: Standards Conversion 24fps to 29.97

PostMon Mar 20, 2017 3:51 pm

jamesharding wrote:Hi Andrew,

Thanks for your reply, I should have been more clear that 24 to 29.97 I just used as an example. In a progressive timeline, if I were to similarly go between 24fps and 25fps, I would expect Resolve to slow down or speed up the video and audio to match the timeline frame-rate without any pulldown, frame blend or motion estimation. Can it do that?

Thanks

James


Yes, 24<->25p can be done with speed up (slow down). Just set desired fps in the clip properties and then dog to timeline. I would just not trust Resolve to do audio speed change- rather use some audio tool for this where you have clear control regardless pitch correction (to use it or not and what method). Better not to do pitch correction at all than do it with poor method. Pitch correction is also very difficult process.

Of course this is not going to work if you ever need to do 24p to 29.97p (way to be speed change). Although it works for some stock footage clouds, water etc.
Offline

jamesharding

  • Posts: 16
  • Joined: Sat Dec 07, 2013 3:54 pm

Re: Standards Conversion 24fps to 29.97

PostMon Mar 20, 2017 4:14 pm

Cheers Andrew, it's really annoying that Resolve cannot handle the sound, to have go to back out of Resolve and in again is a bit of a hassle, particularly when you have over 30 clips to work on. Premiere just does it out of the box. Good to have it confirmed though
Offline

Andrew Kolakowski

  • Posts: 2154
  • Joined: Tue Sep 11, 2012 10:20 am

Re: Standards Conversion 24fps to 29.97

PostMon Mar 20, 2017 4:22 pm

I didn't confirm it :)
Don't know how good Resolve is for this task- I don't use it much at all. Definitely not for such a task.

Return to DaVinci Resolve

Who is online

Users browsing this forum: Joango and 18 guests