Converting 1080psf to 1080p?

Grug

Grug

Veteran
Hi guys,

I've been handed some additional footage for an edit and it's in a 1080psf25 format (in ProRes422). The rest of our footage has been shot in regular progressive 1080p25. So I need to convert the progressive segmented frame footage back into regular progressive frames. Does anyone know how to do this?

Any help would be much appreciated.

Cheers
 
Just tell your editing program to interpret the footage as progressive rather than interlaced.
 
All the field pairs should match up into progressive frames, so it shouldn't be much of a problem even if you don't do anything.

The footage itself may even have metadata telling the NLE to see it as true 25p.
 
It does seem to play just fine, I get horrible interlaced artifacts when I scroll through or pause the footage though (for obvious reasons). On export as a 1080p25 file some clips seem fine, but others hold onto their interlacing artifacts (and show them on playback). Is there no software that can conform the files back to regular progressive?
 
Where is this footage from? Did someone render out as 25psF? If so, the field pairs might be mismatched and that would complicate things.
 
If you don't explicitly tell your video program that your PSF footage is progressive and not interlaced, it may resort to line doubling to fit it to the progressive timeline.
 
David Jimerson said:
Where is this footage from? Did someone render out as 25psF? If so, the field pairs might be mismatched and that would complicate things.
Click to expand...

It was recorded to ProRes on an external recorder, an Atomos Samurai I think. So I'm pretty sure it's the direct SDI output from the camera.
 
My understanding is that the Samurai converts 25pSF feed to 25p for recording.

But, no matter; you've got what you've got. Here's the problem -- 25p footage which goes out SDI as 25pSF should be in proper field pairs -- frames ABCDE go out as fields A1A2 B1B2 C1C2 D1D2 E1E2 and should be matched properly when you get the footage on a timeline -- just like 25p recorded in a 50i stream, as is the norm with many, many cameras. If you are viewing on a 25p timeline, you shouldn't see interlacing because the field pairs should match -- be from the same frame -- and no objects in the frame should be in two different places at once, which is what gives you interlace comb artifacts. You should only see that if the fields are out of order.

Are you editing on a 25p timeline? If you go frame-by-frame -- not scroll, but advance one frame at a time -- do you see the interlacing?

I ask this, because if the fields in the 25pSF footage are out of order, a clean conversion to 25p will be difficult. Just want to make sure the footage is clean.
 
Alrighty, seems I've found a solution! I've used MPEGStreamclip to 'deinterlace' the psf files back into regular 1080p25, and it seems to have handled the re-encoding very well, I can't visibly see any real degradation between the original 1080psf25 ProResHQ files and the new 1080p25 ProResHQ files, so it looks like the segmented frames can be stitched back together without too great a penalty!
 
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