Sporadic pixalation errors

[TG-TONEWORKS]

Hi! I have noticed sporadic errors including sudden pixalation (pl. see example attached) after export of a music video - these errors are not visible when I play the video session in the time line in adobe premiere pro (14.7.0). It seems that there is an overlay of two clips but there is actually only one clip at the time of interest in the time line?! The export was performed with H.264 format (1920:1080) - the errors did not depent on render quality settings. I had these problems before indicating that I likely make any systematic errors? Tx in advance!

[Ann Bens]

[TG-TONEWORKS]

Thanks for your request - perhaps you can already see the problem  in a screenshot. These artifacts lasts for about a quarter second.

[Ann Bens]

Do these errors appear when MPE is set to software?

If so update or downgrade gpu driver.

Post comp specs and  OS.

[TG-TONEWORKS]

these errors do also appear when I set MPE to software. I am using a MACbook pro (mojave 10.14.6, 2.3 GHz intel core i9, 32GB 2400 MHz DDR4) equipped with radean pro vega 16 4GB and intel uhd graphics 630 1536MB. Which driver must be up/down-graded?

[Michael Grenadier]

please tell us your source properties and sequence settings.  By any chance are any of your sources from a smartphone or screen capture?  If so, the issue is probably variable frame rate sources.

use mediainfo to determine whether your source is variable or constant frame rate
https://mediaarea.net/en/MediaInfo/Download
if it's variable use handbrake to convert to constant frame rate
https://handbrake.fr
and here's a tutorial on how to use handbrake
https://www.youtube.com/watch?time_continue=34&v=xlvxgVREX-Y

[TG-TONEWORKS]

...indeed one short clip (4 secs) comes from iphone in full HD - I must admit that I did not care much about frame rate variances despite the clips came from many different sources (youtube stuff, videoblocks, canon camera etc.) - I thought that my settings included an automatic conversion of my imported material to the given frame rate setting of the sequence/project - 25 frames/sec!? Tx a lot for your advice and the link to handbrake website - I will check out this website!

[Michael Grenadier]

unfortunately your sequence settings will not correct for variable frame rate sources.  Adobe is working on this but I don't think anyone outside of Adobe has a clue as to when this fix might be implemented.

[Michael Grenadier]

did you check to make sure ALL your sources are constant frame rate using Media Info?  You might also try deleting your iphone footage from a duplicate sequence timeline and see if that solves the problem.

[TG-TONEWORKS]

ok, I will try to exclude the iphone files in a copy sequence.

[TG-TONEWORKS]

... by the way at least most of the material was imported using Adobe medea encoder...is it possible with this encoder to adjust all clips used in the time line to 25 frames/sec?

[TG-TONEWORKS]

I have adapded all source media to frame rate 25, however, this resulted in reoccurrence of all problematic parts I had corrected before in the time line...funny thing!?

[Steve Griffiths]

Now that we know you are on Mac OS - don't worry about GPU Drivers. They are part of the MacOS installation and can't be changed.

Try 'preview' rendering your entire sequence before exporting and then - assuming no pixelation is present - export as per normal but ensure you tick the 'use previews' checkbox in the export window. This should then produce a usable export.

[TG-TONEWORKS]

Tx Steve, I'm goin' to try these things and come back later to you...

[TG-TONEWORKS]

... I have rendered with preview and no pixalation was observable - I exported with ticked "use previews" box, however, the pixalation re-occurred. Interestingly, when I exported only a small piece of the sequence, for example 15 secs where pixalation usually occurred, there was was no pixalation in the exported file?!?!? This may indicate that these errors depend on time and not location in the sequence - funny thing!? I have also tried different export settings (with and without max. render qual, different codices etc. - no success.

[Michael Grenadier]

did you check to see if your source material is variable frame rate as I suggested earlier in this thread.  That's often the cause of these intermittent unpredictable problems.  

[TG-TONEWORKS]

sorry, did see your comments just minutes ago...and answered above....