Mixdown, it's a common theme with me, because it works…
So today I'm doing something typical. I'm making a ProResHQ movie from my Avid 1080i/59.94 project with 12 audio channels. The material is progressive 29.97 but the network wants a 1080i/59.94 master so that's what the project is. I realize I can toggle between 29.97P and 59.94i in Avid. I spit out my QT Ref .mov and I use QT Pro to save as to the native DNX 220X and I do the same a second time using export to make a ProResHQ version. Now in QT Pro I tell the compressor the source is interlace odd upper field first. Now the fields in this case are really psf's content wise. What would happen if I didn't check the interlace box in QT Pro. Would it make a QT that is truly progressive in nature as far as the video essence is concerned? I think my underlying curiosity is does the video essence in the files that are interlace have video data in an interlace order odd lines and then even lines or is the video essence in a straight progressive order and the handling of the file by the player extract odd lines and then even lines to create a psf signal suitable for HDSDI tape feeds. Basically does the video data in an interlace file follow an order similar to the standard composite video interlace or is it always a progressive order top to bottom in the file video data?
If I export
---In Avid-L2@yahoogroups.com, <cutandcover@...> wrote :The only time progressive becomes PsF is when it goes "outside the box". That is, when it comes out into the world, out of the computer. Inside the computer, in any application, progressive is always progressive. When you want to transmit progressive frames over SDI or HDMI, you can do it as PsF. When you want to store progressive frames on tape, you can do it as PsF. But inside the computer, any file that is progressive is pure P, no sF.
On Sun, Apr 13, 2014 at 10:22 PM, <bigfish@...> wrote:Thanks for reminding me. I was just trying to understand better what the issue with Resolve round tripping and having psf and interlace files separated for export. I concur that electronically it doesn't differ electronically whether its fields or psf's making up the video essence. The only important thing is field order. That's where I'm curious what deleterious effect there is to rendering out of Resolve media that is psf to interlace. Perhaps I need to reread and I mistook psf for progressive media. Progressive media in Avid has traditionally been psf under the hood if I'm not mistaken. At least in my predominantly 59.94i delivery world it is when dealing with progressive material to tape and HDSDI world. So I guess the real question is what is it about interlace vs a true progressive file rendered out of Resolve to avid mxf that makes it necessary to separate the two types of media render out in different passes. I get that Resolve can't export both types at the same time but what is it in Avid that would make the round tripping a problem if progressive got baked out as interlace. I don't generally deal with much 23.98 so I'm probably missing something obvious.
---In Avid-L2@yahoogroups.com, <cutandcover@...> wrote :You know there's no such thing as PsF file media, right?
On Sun, Apr 13, 2014 at 7:37 PM, <bigfish@...> wrote:You mentioned having to separate out interlace vs. progressive. What is the issue if psf media gets rendered out as interlace? Electrically they are the same just the temporal difference between the fields. Avid has no issue Ive come across mixing them. Does it create a relink issue when coming back to Avid. IIRC in avid I can change the motion type of clips in the bin and the media still works.
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