ADOBE AFTER EFFECTS: Forum Expressions Tutorials Creative Cloud

Juddering? Dropping frames?

COW Forums : Adobe After Effects

<< PREVIOUS   •   FAQ   •   VIEW ALL   •   PRINT   •   NEXT >>
Jay Gordon
Juddering? Dropping frames?
on Mar 5, 2013 at 5:05:24 pm

I apologize in advance for the length of this post! I also apologize if this isn't the right place for this (I'm not really sure if this is a problem solvable with After Effects, or a problem with Flash Player, or just something I'm doing wrong at a base level).


I feel I should note that I'm pretty inexperienced when it comes to movies and filmmaking in general. That being said I've done quite a bit of research over this past month trying to get to the bottom of this problem I'm having.

Here's the rundown: I'm making a video not from actual footage but from a 3D animation I've made. The animation was rendered out in a JPEG sequence (so plenty of control there). It's then taken to after effects for some post work and to be rendered out as an mp4. The video plays smoohtly on the computer, great. Once uploaded to YouTube though? Extreme juddering. Uh oh.

Video:





First thought? Well this is somehow Youtube's fault. Let the video buffer completely, tried different settings in the player. No dice. Try Vimeo. Still there. Different browsers? Nope, all the same. Maybe these sites are doing something to the video when they compress it down? Download the mp4 off of YouTube. Plays fine. Well then...

Secound thought: This is Flash Player's fault. Plenty of evidence to back up this thought too. If I use YouTube's HTML5 feature it plays fine. If I play it in flash player on my PC it judders. I've seen some other videos on YouTube (mostly one's similar to mine) judder in the same way. But...then why do some video's on YouTube play absolutely fine?

HTML5 video: A week ago adding "&html5=True" to the end of a video link (that wasn't ad enabled) worked, now it seems not to. You'll have to goto youtube.com/html5 and enable html5 viewing then revisit the video above.

Third thought: Okay okay..This is somehow my fault. And it very well may be. At the end of my metaphorical rope, while doing a final bit of research, I learned that -any- movie at 24fps panning like my video does will judder; and that filmmakers use various techniques (or just avoid it) to compensate. Well that's fair. I had no idea this was an actual thing. But..My video runs at 30fps, -and- runs smoothly on the computer (and much smoother in html5 than it does in flash). So..That sort of unravels that theory also.

I've exhausted all the theories, settings, and fixes I can think of. Logic has long since left the building! And my boss is none too pleased that I haven't "just fix this thing already" yet.

Any help, even just a point to a direction where I can possibly find some help, is greatly appreciated.

Thank you.


Return to posts index

Joseph W. Bourke
Re: Juddering? Dropping frames?
on Mar 5, 2013 at 11:18:06 pm

I believe the culprit is you mp4 compression, which is a temportal compression. I'll bet that if you output a Quicktime movie out of After Effects, say in Mjpeg-A format at 90 quality, then upload to YouTube, you won't see the juddering.

The safest bet might be to just output a short chunk, maybe 10 seconds or so, and do the test on it. I'm thinking it will solve your problem. Good luck...

Joe Bourke
Owner/Creative Director
Bourke Media
http://www.bourkemedia.com


Return to posts index

Jay Gordon
Re: Juddering? Dropping frames?
on Mar 6, 2013 at 12:34:45 am

Thanks for the reply. Quicktime was one of the formats I hadn't tried actually, so I quickly jumped on to testing this.







Unfortunately the studdering/judder is still present. The issue is one that is only ever visible when viewing from within Flash Player. The direct download from Youtube, viewing in html5, and playing the original render, from my PC all play smoothly.

All of my trial and error points to Flash being the culprit, yet most youtube videos play just fine.

My current solution will be to just use cuts instead of panning, and pan slower when necessary; since it seems the juddering is only noticable during pans (which play smoothly anyway outside of flash player)


Return to posts index


Joseph W. Bourke
Re: Juddering? Dropping frames?
on Mar 6, 2013 at 3:21:08 am

Is it possible that the bitrate of the Flash file is too great for the connection speed? Or does the local Flash file on your computer judder as well? It just seems odd that the Flash file on YouTube plays back fine, but your local file (if this is the case) doesn't. All I can think of is that the local file is too much for your graphics card to play back, and when it's encoded on the YouTube end, that brings it down to a size that can handle the throughput.
Puzzling...

Joe Bourke
Owner/Creative Director
Bourke Media
http://www.bourkemedia.com


Return to posts index

Jay Gordon
Re: Juddering? Dropping frames?
on Mar 6, 2013 at 1:40:56 pm

Playing it through Flash Player at all causes the juddering, whether it be on YouTube or putting it into a flash locally. I've used a bitrate as low as 6, having the same thought cross my mind.

Am I the only one seeing the juddering/skipping in the youtube video linked? I have checked it outside of this building, and on multiple computers; to no avail.

It is very puzzling! Definitely losing some hair over this one.


Return to posts index

Joseph W. Bourke
Re: Juddering? Dropping frames?
on Mar 6, 2013 at 4:11:12 pm

Hi Jay -

No...I see the juddering on the camera moves. I believe you said that this was all done in 3D, correct? One last thing I can think of is that somehow your 3D output is the problem. When I output stills, and even Quicktime movies from 3DS Max, I always output them at 60fps. When I output at 30fps, I sometimes get a similar stutter in my output, especially when elements are moving through the frame in the x or y axis. Maybe try outputting a snippet of your animation at 60fps? Then when you import into AE, set to 30fps and you're good to go...I hope...

Joe Bourke
Owner/Creative Director
Bourke Media
http://www.bourkemedia.com


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]