Just spent some quality QC talk with a network we are delivering to and much to my disappointment they no longer accept 2:3 pulldown. Even though they can broadcast it just fine the ancillary interwebs and international concerns are the driving force for not accepting 2:3 pulldown. I completely understand that a 2:3 pull down doesn't technically fit in a 29.97P but still this makes me throw up in my mouth just a little bit.
So I asked the question to the Network QC folks. So if you broadcast in 720P how do my 29.97/sec full frames that are packed in a Psf structure of 2 Psfs per frame get distributed across the 59.94/sec 720P frames. I was told that the 29.97 full frames were doubled up in the process. They didn't seem completely certain about that so I'm looking for some clarification.
In my mind the simplest way the 29.97P to 720P conversion would happen is for each Psf to become one of the 720P frames. Now I'm curious how the conversion of 540 lines per Psf to 720 lines in 720P happens. But according to the chat I just had with Network QC what they say happens is the two Psf fields are combined to a full frame and that is the info that is packed into the 720P frame and they repeat the same frame so the 30 original frames are doubled into 60 frames.
For an interlace 59.94 conversion I'd have to bet that each Psf becomes a unique 720P frame thereby maintaining the smoother motion so I just figure basically the same things happens when the source is 29.97P but that's an assumption that seems to be incorrect according to my QC chat. Can someone beat me over the head with split frames until I can let this go? ;-)
John Moore Barking Trout Productions Studio City, CA bigfish@pacbell.net
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Posted by: John Moore <bigfish@pacbell.net>
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this is the Avid-L2
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