Native 24p Mode

G

gunti

Member
I have tested two stable settings with 32gb sandisc class10:
You can see the Native 24p unwrapped pic and the one with no native but more bits. The native seems to be more sharp and the wrapped standard more may cover unaestetic artefacts, seen in the native pic - look the red leaf of the plant, especially where the plant roots cross the red leaf in the zoomed part.



1283880082.jpg



recorded in FHD
settings were:

Native = OFF
FHD/SH60000000
Overall: 62000000

and

Native = ON
FHD/SH40000000
Overall: 42000000

Only possible with class10 card.
 
When you do the proper pulldown they are identical. Depending on your media player and its settings you may see loss of quality on 60i footage. The advantage of shooting native other than one less step in post is that you can change the gop length thereby removing static noise.

edit: actually you can change gop in 60i...
 
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No they are not identical even when unwrapped properly (i.e. with pulldown removal). The wrapped 24p uses interlaced color subsampling and the native 24p uses progressive subsampling. There will be a difference in edge sharpness on saturated colors. Displaying in 60i results in incorrect ghosting because the stream isn't really interlaced data, its progressive data in an interlaced wrapper.


Chris
 
What makes everyone so sure that the camera is sending native 24p frames anyways? What's keeping it from doing its defacto 60i wrapper, then unwrapping it? That would at least explain the instability. At least from what im seeing in my own tests so far, there is definitely something different about it from what i can get removing pulldown manually.
 
I agree that there is something else that is different as well. It is indeed 24p in a 60i wrapper - you can see that by stepping through. However, I ran some tests in 25p mode and noticed that the ratio between I frame sizes and P frame sizes changed when I switched between native and wrapped mode - and they should be the same. I tested 25p because it doesn't add any frames when it does the pulldown. Something else is going on. I'm trying to drill that down now - it's a big project, so it might take a while.

I also ran some tests with an electronic slate where it counts frames, displaying the frame number- the 24p footage, whether native or not, came out as true 24p.

Chris
 
Im beginning to see why determining anything will be such a nightmare. For the same frame from a n24p clip im seeing different results in vdub, which produces sharper edge noise, mplayer (vmr9 renderless) which has smoother edges, and AE cs5 (full res preview, interpetation aside) which is produces the subsampling issue on saturated areas (red edges in particular). In fact, everything i put through AE, regardless of container or interpretation, looks like crap, but maybe its more true to the source than the others.


Similar issue with doing pulldown, im getting interlace artifacts (read: these programs are actually trying to deinterlace) using AE 3:2 pulldown removal and this hv20 batch remover. Im not sure what else to use as none of these programs can figure out what panasonic is actually doing.

edit: same thing in vdub's 3:2 removal, interlace artifacts. Unless there is a way to remove pulldown successfully, 60i footage is worthless.
 
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