720p60 footage has duplicate frames

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Level 1

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720p60 footage has duplicate frames

I'm working in FCP7 on a project and have been given 720p60 footage that was shot on a Varicam 2700. The problem I'm having is that, while this footage is being read as 59.94fps, each clip has duplicate frames and therefore is not actually giving me a unique image per frame.

Just to clarify, I am fully aware that back in the tape days the Varicam used to always shoot 60fps but would flag frames based on the framerate you had set, and then in FCP you simply clicked the 'remove advanced pull-down and duplicate frames' button in Log and Transfer and you'd be set. However in this instance that option does nothing to the 59.94fps footage, and for the last three years all the Varicam material I have received has been either 720p24 or 720p25 (which offer a variable framerate of 1-60fps and 1-50fps respectively) which I've used with no problems.

I've spoken to a friend at a local post-house and his solution was to drop the 59.94fps material into sequences of different framerates until I found the 'correct' one e.g. if a clip was doing the classic 2:3 pulldown this would make it 24fps - you just drop it into a 24fps sequence and FCP will correctly remove all the duplicated frames. You can then simply export that sequence and reclock it in Cinema Tools with no problems. While this is a great solution, the crux of my problem is this: the number of duplicate frames differs from clip to clip, despite all of it being read as 720p60 with a framerate of 59.94fps. I' ve had a look at the number of duplicate frames, and it's clear that some clips are 23.97fps, some are 29.98fps, and some are actually 60fps. It's as if each clip has its own unique framerate but for some reason all of it is being read as 59.94fps and there's no metadata to tell FCP otherwise. What this means is that I can't simply dump all the clips into one sequence and export them - the only 'solution' would be to manually check each clip, figure out the real framerate, and then dump them into the relevant sequence. I have hundreds of clips, so this is not a particularly decent solution!

My question is this: is there a program or plugin that can either a) remove the duplicate frames or b) analyse each clip and tell me the correct framerate? Keep in mind I've tried the usual solutions of running the footage through Cinema Tools or QT Edit (doesn't work - the duplicate frames mean the reclocked footage becomes super-janky slow-motion), plus the 'advanced pull-down/duplicate frame' option in L&T doesn't work because FCP is reading it as 59.94fps with no flagged frames.

Has anyone come across this problem before? Any idea how the cameraman even managed to record footage like this to P2 cards? Any help or advice would be much appreciated!

ps. two things: first, my finished sequence needs to be 25fps and the sync material is at 25fps, so I can't just work in a 60fps sequence to solve this problem. Second, the cameraman apparently wasn't using an external video capture box, which might have explained the discrepancy between the stated framerate and that actual amount of frames captured. It's a tricky one!

Final Cut Pro 7, Varicam, 59.94, duplicate frames

Posted on Jul 19, 2014 5:24 AM

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Answer 1

Jul 20, 2014 9:00 AM in response to Bumhat

Not sure if this will work, but you might try using compressor to remove pulldown. Duplicate and customize the appropriate preset and enable frame controls in the frame controls panel and under the resizing control set deinterlace to reverse telecine. It's done a great job for me in removing pulldown with needing to know the cadence of each individual clip. If any of this isn't clear, post back with your questions.

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Answer 2

Shane Ross

Level 8

43,110 points

Jul 20, 2014 11:58 AM in response to Bumhat

The camera was called a VARICAM because it shot variable frame rates...but all within the 59.94 stream. You can set the camera to shoot 60p, 30p or 24p. And then you'd have to set up FCP with a 24p or 30p project in order to capture the footage as 30fps or 24fps...it'd detect the flags on the footage as 30p or 24p.

BUT...this is a big problem if multiple frame rates were shot to ONE tape. Then this is pretty much useless. You'll have to capture the footage as 60p...then separate out the individual shots and remove pulldown AFTER....so detect what sort of pulldown it has, then run the footage through compressor. This is why we INSISTED that camera people change the tape when they shot a different format. We had 24p for most of the show, but they shot 60p for some shots we wanted slowed down.

Multiple frame rates on one tape is a mess

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Answer 3

Bumhat Author

Level 1

0 points

Jul 21, 2014 2:13 AM in response to Shane Ross

Thanks for the advice so far - Michael, I'll give that a shot, and Shane, can you think of how this might have occurred with a Varicam 2700 shooting to P2 cards? The tape situation you described sounds like an absolute nightmare, but I didn't think this was possible with a Varicam shooting to a card as you can set the camera to 720p24 or 720p25 and then choose your desired framerate. Is there a setting where you can - for lack of a better term - go into 'Varicam classic' mode and change the framerate on the fly but have the camera constantly record 60 frames (regardless of whether or not they're each unique)?

My knowledge of the internal workings of the newer Varicams is admittedly pretty poor, I have perhaps been spoiled by only receiving 720p24 or 720p25 material prior to this problem arising. I have never once had to deal with this issue and I cannot find a single other person online with this exact problem (of mixed framerates jumbled up within footage that is all ostensibly 59.94fps) when using Varicam footage recorded to a P2 card.

At this point I'm just considering biting the bullet and doing the edit with the footage as is, and then - when I'm finished - manually labelling the 59.94fps material I've used, checking/converting it, and then replacing it in the cut. This would be time consuming but it'd be a **** of a lot faster than preemptively checking every clip and converting it beforehand.

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Answer 4

Bumhat Author

Level 1

0 points

Jul 21, 2014 4:09 AM in response to Bumhat

Ok, I've spoken to another post-house and it looks like we've got to the bottom of it - we're pretty sure the cameraman was shooting in an obscure mode called 'Overcrank Shooting' whereby you choose the system frequency and system mode as you would when using variable framerate, but you can't drop below 25fps and the slow motion effect can only be used in a NLE system if you've set the Rec Format to DVCPROHD.

Given that a) this setting only works with DVCPROHD and b) we're working in a 25fps PAL project, the cameraman of course set the Rec Format to AVC-Intra and obviously set the system frequency to 60Hz, rather than 50Hz. Euuurrgghhhh. This would explain why every program I've put the footage into (Avid 6, FCP, P2CMS) cannot give me any information other than 59.94fps, which is basically useless given the actual framerate differs from clip to clip.

Michael, I tried your Compressor settings and they kind of worked although a few duplicate frames still crop-up and the footage looks strange in motion as it's cutting out frames to make it 25fps (thus looking overly sharp). It's still an improvement though and I'll play around with the settings a bit more, so thanks.

I think we'll just cut with the footage as is and then convert the files we've used afterwards, to avoid having to manually sort out hundreds of clips we probably won't even use.

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