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I'm noticing a weird glitch in my video only in the first few seconds of playback.
For some reason it is only happening on this one project so far. Even when I have changed the intro the new intro now has this glitch.
It does not happen with every export but more so than not.
I have deselected "use preview files" to help get rid of any weird rendering that may have occurred early on and also deleted all render files from project just in case.
Any ideas what else I can do?
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Gonna need more info on what exactly you mean by "glitch." Screenshot would be helpful.
is this only on renders or does it show in the program monitor as well?
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Hey Jeff,
Thanks for responding, I just wanted to get the ball rolling. It does not show in the program monitor, only export.
Here is a ss of the video:
You can see where it's in the middle of the glitch. It does that several times in the beginning. Previously I started with just video instead of a logo and the video did the same thing:
I marked some areas because it isn't as noticeable in a still but when it pops in and pops right back out you can tell a lot.
It is a 360/VR video, 7680x3840, H.265 and so on. Let me know if you need more specs. The glitch happens on mulitple play back devices and is not in the original footage. Also it happens when exported in H.264 in 4k.
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That looks like low bitrate artifacts.
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I'd agree however I am at a 160 mbps target and it only happens for the first 2-4 seconds and the rest of the video is fine.
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What happens if you export to Cineform, which is a Quality-based codec with unconstrained bitrates?
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I do not see that codec. Is that a plugin I need to get? Also does it support VR video and can you upload/play it on YouTube/Oculus GO?
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This is a crazy idea...but could be tested by just using work area selection to export for few seconds... see if it works.
Years ago some stuff that had transparent backgrounds ( alpha) did weird stuff, like breaking up etc...glitchy. Not always.
It was discovered that putting black video under the stuff fixed the problem. Might be worth testing just for fun ?
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Sure, I will test that.
However it's not just alpha that does this. When I had just video in the beginning of my edit I did a test and the video also had the same glitch.
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Yeah, I know. That sorta blew my theory out the window. But then I thought, "how does 360 stuff shoot ? does it have some embedded alpha thing that defines the 'space' and then shots are stitched into the space as it shoots or what ?? I have no clue.
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I did a short 10 second clip in the middle of the video and I did not notice the glitch.
Seems to be something with the longer duration. My entire video is just under 4 minutes.
I am attempting a full export now with media encoder to see if it makes any difference. The only other thing I have changed is turned off Key Frame Distance which is default off usually anyway but I added it to try to get some better quality for the 360 footage.
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Hey Jeff,
Did you get to take a look at the info?
Also the post was accidentally answered and is sinking to the bottom. Was wondering if you know anyone that can help with that.
Thanks.
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I also just accidentally "assumed answered" and it is not answered and I can't figure how to make it go back...
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That's OK, we'll just ask a MOD to change it
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There are a lot of variables involved and the trick is to sorta narrow things down and fix stuff in a methodical way. You first said that the first 4-5 seconds was messed up and the rest was OK. So let's focus on the first few seconds, instead of exporting ( testing) the middle of the footage which was OK anyway.
Don't worry, you'll fix it and get it looking great. The worst thing that can happen is that you roll back to a version of CC that worked before for all your earlier projects. Don't throw the computer out the window yet !
: )
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After this one is done exporting I will do the front end test.
It's odd that no matter what the beginning is it does it.
Also now that I have reviewed it several times it really is only the first few frames up to maybe 1 or 2 seconds. However it's enough for a co-worker or supervisor to go "ohhh"...
I'd hate to start with pure black for 2 seconds to force it to happen and not be seen but I may have to do that...
I feel like this may be something with just this particular project file?
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oh noooo….
black video is NOT SOMETHING YOU PUT IN TIMELINE IN FRONT OF CLIPS !!!!
hehe...
Let's say you have footage on V1 … video level 1. You have problems that MIGHT be associated with some weird alpha stuff. No harm in trying the black video thing. Probably won't work, but it's only a few seconds of video to test it out.. who knows ?
Anyway, what you DO is you move the portion that is screwed up ( the first 5 seconds in your case ) to V2 ( next level UP in timeline).
THEN YOU ADD black video to V1 UNDER IT . You don't do anything more than simply add black video UNDER.
I'll try to do a quick demo...brb
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I get what you are saying now...I was wondering what you meant if I had to remove all my video and put just black...Of course I wouldn't see a glitch anymore!!
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hehe, I'm probably just wasting your time now, sorry. I have no clue if his might help. But it's only a few seconds of timeline so I figured it was worth a try. A long shot.
Anyway, here is the illustrations... you'll figure it out. I'm using CS6 but you'll find the necessary stuff to do the same on the new and improved version of CC.
good luck !
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So I did both just the front end and front end with black underneath and still have it...
So not sure what's next.
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me neither. sorry. Someone else will have an solution !
: )
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This is info about cineform, Jim's recommendation.
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So morning update.
I made a new sequence to see if maybe it was just a glitch in the previous sequence.
I also added 10 seconds of black to the front, set my in after that to see if I could get the same result like I did when I took a section from the middle.
These did not work....
I am starting to run out of ideas.
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I may have a lead. I have removed the transition "VR Iris Wipe" from the back end of my clip....the distortion wasn't even connected to the time I was viewing however it seems like it may have been effecting the entire clip?
My mind is currently blown. Going to do a longer version test to see if this holds up.
Edit: I actually tried 3 things that trial. I also ran at CBR instead of VBR 1 pass (which hevc only allows one pass for some reason) and time interpolation from frame sampling to frame blending....not even sure what those do but for some reason on my preset it was set to sampling when the default is blending.
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Ok so it seems that I have narrowed it down to VBR vs CBR.
When using media info to examine the files I notice that a file that was exported in VBR does not state it is VBR like other files I export in H.264 instead it just states one bit rate. I wonder if there is some error with the VBR option in Premiere for H.265.
For the time it seems like CBR is what I am going to use if it continues to work even though I may be sacrificing some drive space.