Page 1 of 1

Strong artifacting after rendering to prores

Posted: Mon Jul 14, 2014 7:05 pm
by Carlitos
Thanks in advance for any feedback. I'm using the Neatvideo AE plugin. I'm getting truly impressive results in the ram preview. However when I export the clips I get some pretty serious artifacting in the regions that go from light to dark. It looks more like big blotchy, chunky artifacting then standard video noise. The footage is lit in an expressionist manner so there's a lot of that and as a result the skin tones can look posterized.

It's dslr footage that was originally h.264 and was transcoded to prores 422. I used clipexporter (a lifesaver) to open my fcpx project in AE. After denoising the individual clips in AE I'm exporting them to prores 422. I am planning on relinking my fcpx project to the newly denoised clips if I can manage to get the clips to look right. To test if I was just getting bad exports from AE I exported one of the clips with no effects applied and the result looked just like the original noisy footage w/o the blotchy artifacting.

I've never been an Adobe wiz so there may be a codec setting I'm missing when I render/export. I'm exporting to prores 422 (w the default settings, not HQ or LT) because it matches the transcoded footage from the fcpx project and when possible or if there's no upside I'd like to keep the file sizes down. Thanks for taking the time. I hope this is all clear.

I'm not sure that any of this would be relevant but:
AE CS6
FCPX 10.9
Clipexporter 1.2.5
Mavericks
I'll have to look up the GPU
Let me know what detail I've inevitably forgotten to include.

Posted: Mon Jul 14, 2014 8:37 pm
by NVTeam
Which exactly version of Neat Video is it?

For a test, please replace Neat Video plug-in with Gaussian Blur effect and render again. Will you receive the same banding (I assume you are referring to banding)?

Thank you,
Vlad

Posted: Tue Jul 15, 2014 9:11 am
by Carlitos
Thanks for the quick response Vlad. It's NV version 3.1.0 for AE. I applied the Gaussian Blur and rendered to Prores 422 with the default settings like you recommended. I did not get the banding I had described in the previous post. I was not sure whether to call this type of artifacting banding because i thought banding radiated out in a fairly organized pattern. What I see seems random. Maybe I've just been misusing the term. Have other people described banding issues when exporting to prores?

Thanks again

Posted: Tue Jul 15, 2014 9:34 am
by NVTeam
Then I guess it is best to see some actual examples of the problem. Could you post some screenshots please?

Please also update NV to 3.5.

Thank you,
Vlad

Posted: Wed Jul 16, 2014 11:21 am
by Carlitos
Vlad,

I think I got it figured it out. In case anyone else has experienced a similar problem with this workflow the solution for me was to change the project settings to 16 bit and use Prores 444 at millions of colors for the output settings. It seems like overkill but that was the solution. Outputting to trillions of colors created posterizing in areas that go from light to dark. Adjusting the other working space or color profile settings in After Effects did not seem affect the results appreciably. With footage that has very contrasty lighting I found it helpful in NV to check the "remove very low frequency noise" box and focus especially on removing noise from the blue channel. I'm very impressed with the results. I think having the native fcpx plugin is really the way to go in the future because this was a lot of work. You also save a lot of HD space if you don't have to create Prores 444 transfer files when you move from AE to FCPX.

Thanks for the quick response Vlad

Carlos

Posted: Wed Jul 16, 2014 11:28 am
by Carlitos
Oh, btw, I tried out Denoiser II. It's a decent plugin but with challenging footage like mine Denoiser is garbage compared to NV. No comparison.

Posted: Wed Jul 16, 2014 11:35 am
by NVTeam
So the problem originated in 8-bit precision of that project and switching AE to 16-bit rendering helped, is that correct? Interesting.

Thank you for sharing.

Vlad

Posted: Wed Jul 16, 2014 12:14 pm
by Carlitos
Not exactly. It was switching the AE project settings from 8 bit to 16 bit that really did it. I rendered to millions of colors (the default for prores 444) which, if My research was correct, is the same as 16 bpc. I have no idea why that worked. The script I ran to open the fcpx project in AE refers to Canon dslr footage which is 8 bit h.264. It is interesting.

Carlos

Posted: Wed Jul 16, 2014 12:42 pm
by NVTeam
Thank you for the clarification.

Vlad