Marker Time Shift with 23.98 Youtube Export

[davef43726944]

I have several long videos shot/edited/exported in 23.976 that I am pushing to Youtube along with the chapter markers. What I've noticed is that both Quicktime and Youtube are reading my 23.976 export as 24p. For example my sequence is 01:55:04:21 and the exported file in QT/YT is around 01:55:11. When I reimport to PP the length is read correctly and as 23.976.

The biggest issue is that chapter markers and timestamps for overlays on YT are now misaligned. Any idea how to solve this in PP? I can't recall having this issue before, but it's been a while since I've uploaded to YT.

[RobShultz]

24fps is a rounded up number. I don't believe that you can change this in Premiere Pro.

[Remote Index]

Hello dave etc.,

What I've noticed is that both Quicktime and Youtube are reading my 23.976 export as 24p.

That is very odd - Quicktime should be reading and reporting 23.98fps on such an export. Have you doubled checked you are not changing the frame rate in export settings? What codec are you using for export?

R.

[davef43726944]

Not entirely accurate, but the point is that there is a drop/non-drop mismatch between my sequence and exports and I need to reconcile that.

[davef43726944]

Yes I've triple checked. As I said, it reads as 23.98 when I re-import it to PP. It's just the mismatch in QT and subsequently Youtube that are my issues. I'm exporting h264.

[R Neil Haugen]

In the prefs there's an option for drop/non-drop behavior. What's your setting set to there?

Neil

[davef43726944]

Neil which setting are you referring to in the prefs? Indeterminate media timebase?

[R Neil Haugen]

Not at my computer right now, but that might be it ... options are for drop/non-drop, of the option I'm thinking of. 

Just curiuous how that's set, and whether changing it might change the behavior you're getting. As an idea to check. Because what you're getting is a royal pain, no question.

Neil

[davef43726944]

Indeterminate media timebase is set to 29.97 drop, but it shouldn't have anything to do with my video clips. They are all reporting as 23.976

[Remote Index]

Hello dave etc.,

there is a drop/non-drop mismatch between my sequence and exports

You seem to be confusing frame rate with timecode.

Drop and non-drop options do not affect frame rate, though they may affect the way duration is reported. Drop and non-drop are different ways to display timecode and are relevant only to 29.97 (and 30) frame rates. [If someone can chime in about their relevance to 59.94fps and 60fps that might be helpful].

https://en.wikipedia.org/wiki/SMPTE_timecode

"the drop frame bit is only valid for 29.97 and 30 frame/sec." [per the SMPTE standard]

To be clear:

1. drop or non-drop timecode options will not change the number of frames of media, only the way they are labelled.

2. You are reporting issues with duration on a 23.976fps (or 23.98fps)

3. drop and non-drop are not stictly relevant to 23.976fps media (by SMPTE standards)

However ... Premiere Pro does support  non-drop 29.97 timecode for 23.976 sequences.

Are you using this option?

R.

[Edited, importantly, for the "however" part]

[davef43726944]

Everything is 23.976 as I said. 

[Remote Index]

Hello dave etc., I just edited my comment above - see the "however" question. R.

[davef43726944]

However ... Premiere Pro does support  non-drop 29.97 timecode for 23.976 sequences.

Are you asking if I changed the sequence timecode readout to 29.97 drop? No. That number is totally incorrect.

[Remote Index]

Hello dave etc.,

Okay, thanks for that last bit of info.

Reviewing this, what has happened is clear (apologies for not coming to this sooner): 23.976fps media is labelled with 24 frame code. This means that it is not accurate for duration measurements.

Think about it this way: your media is running at a bit less than 24fps ... that means that if you play 24 frames, it will last a bit more than a second. (actually 1/1000th of a second longer than 1 second).

Over long durations that adds up.

Quicktime and youtube are reporting duration in terms of clock time - how long the media actually takes to play at 23.976 fps. Premiere Pro is displaying 23.976 "duration" in terms of timecode - the number of frames, labelled as they are.

I can confirm a that 1:55:04:21 in 23.976fps (base 24) timecode sequence in will be 1:55:11:24 (or thereabouts) in actual time.

You can confirm this too by nesting that exact sequence in:

a 24fps sequence

a 29.97fps drop frame sequence

(both of these sequences display timecode that is clock accurate ... or, well, close enough for broadcast).

When working with 23.976 media you have to be mindful that durations need to be checked - particularly if you are delivering to broadcasters.

(One aside - there is no equivalent of 29.97 drop frame code for 23.976 because there is no simple enough mathematical formula that would work in the same way it does for 29.97)

(The only mystery here to me is why quicktime is reporting your clip as 24fps - I have no explanation for that, and it threw me).

R.

[davef43726944]

I had a feeling that the answer was basically, deal with it. Pretty damn lame. I have over 50 episodes ranging from 1-2 hours that have to go up to Youtube with timestamps and our team needs to use marker times to communicate various other notes. All of those will need to get converted with timecode calculators. Pretty unpleasent issue to deal with. 

[Remote Index]

I have over 50 episodes ranging from 1-2 hours that have to go up to Youtube with timestamps and our team needs to use marker times to communicate various other notes.

I'm not clear on the details of the whole workflow here, but I'd consider nesting each episode in a 24fps or 29.97fps (drop frame) sequence and using those times for markers.

(You could also try a new post to solicit suggestions for this problem - markers for 23.98 across the versions / formats involved and/or how best to arrange)

R.