24 fps Animation interlacing in a 29.97 sequence
by Colin Edelman
on
Jun 13, 2008 at 6:22:29 pm
Hi,
I have a nightmare AVID project that I wish would end already, but alas, here I am.
I am trying to put together a 29.97 SD uncompressed QT from many different formats with various frame rates:
1080i/29.97, DV 29.97, DVProHD 24p, animations at 24p.
The problem is that there is heavy interlacing which is most noticeable in the animations after exporting.
To get the animations looking fine (without a jumpy effect) on a TV connected to the Avid, I imported the animation files (24fps 864x325) into After Effects and rendered them so they were 864x486 with 2:3 pulldown (SSWWW).
Within the Avid sequence, all of the animations have motion effects (all speed ups) which have been rendered with Fluid Motion.
After getting to final picture, I exported uncompressed video from the Avid (compression type: none) and got heavy interlacing, which I understand is expected while on a computer screen. However, burning the same QT (after it is ran through Compressor) to a DVD still produces the interlacing while watching on a TV.
I ran the QT through compressor with every option for Field dominance: bottom first, top first, progressive. Yet, there is still visible interlacing on each take of the DVD.
I then exported with compression type as Uncompressed 10bit 4:2:2 twice, one with even (lower first) and another with single field. I also ran both of these through every compressor option. So far the Uncompressed 10 bit 4:2:2 with single field from avid and bottom first from compressor looks best, but still has interlacing.
My next test (which I am currently running) is going through the animations within the Avid sequence. In the motion effects window, I go to FORMATS.. and am testing each INPUT and OUTPUT. I am going to test every option, but I think the best would be INPUT: Film with 2:3 pulldown (since that's what I made in After Effects) and OUTPUT: Interlaced. I will update the post if this actually works.
There have to be 1000 variables to this one, hopefully someone has cracked the code previously and knows the proper workflow.
Re: 24 fps Animation interlacing in a 29.97 sequence by Michael Phillips on Jun 13, 2008 at 8:59:06 pm
Why go through the 2:3 pulldown insertion in After Effects if you are going to speed them up anyway in Media Composer? Try this and I believe you might get a better quality result after the FluidMotion stage; import QT (assuming no audio tracks) with a console command of "ignoreqtrate true" which will bring in the original 24p animation in frame for frame. When playing back, it will now be 25% faster but no field based artifacts. Now calculate you speed up based on that - depending on need, you may actually need to slow down. Fluidmotion then won't have to deal with the 2:3 pulldown interlace across frames.
Re: 24 fps Animation interlacing in a 29.97 sequence by Colin Edelman on Jun 17, 2008 at 9:47:44 pm
Thanks for the response, Michael.
When I imported the 24fps animation with the console command "ignoreqtrate true," it definitely looked smoother than when adding 2:3 pulldown in After Effects.
However, I still needed to add a speed up to the animation and when I did, the interlacing was still apparent on a DVD on a TV after running the exported uncompressed Quicktime through compressor. (When the speed up wasn't there, the interlacing was gone).
The workaround to this was making a Digibeta of the entire cut, reimporting it 1:1 into Avid, and then exporting it as an uncompressed QT. This solved the interlacing issue on a DVD seen on a TV.
The lesson learned was that Avid couldn't handle 7 video layers with effects on almost all of them. I suppose the workaround was similar to the process of baking the files when going from Final Cut to Color.
Re: 24 fps Animation interlacing in a 29.97 sequence by Colin Edelman on Jun 19, 2008 at 2:18:50 pm
yes, I tried a mix down as well, but this didn't help.
I would think the process of going out and then back in through a digibeta would work because the Avid is ingesting a whole new file without effects (since they are inherently in sequence) which seemed to be causing the problem in the first place.
