Stutter-jerkiness on horizontal scrolling animation

[Tudor “ted” jelescu]

I had the same issue one time- I can’t say that I figured it out, but here’s what I did that worked for me:
I rendered an uncompressed interlaced output (1920x1080i 29.97fps and then I compressed using Adobe Media Encoder to my final format which was 1280x720p 29.97 flv.

Tudor “Ted” Jelescu
Senior VFX Artist

[Walter Soyka]

Hi Shawn,

Do the rendered comps play acceptably on another computer?

This is a very out-of-left-field idea, but I recently had a very similar problem, where playback of any media on my Mac seemed to stutter [link]. After a little more investigation, I realized my Mac was actually completely unresponsive for a frame or two’s duration every few seconds.

I had two DVI displays physically connected to my Mac, but one was turned off. Turning the second display on (or unplugging the DVI connector) cured the stutter. My best guess is that this is related to HDCP polling.

Walter Soyka
Principal & Designer at Keen Live
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
RenderBreak Blog – What I’m thinking when my workstation’s thinking
Creative Cow Forum Host: Live & Stage Events

[Kevin Camp]

when you play the file back in quicktime with the movie inspector open, do you see the playback fps drop at those points in the movie?

if so, then it would be a case of it choking on the data rate at that point in the file.

if not, then i think at those points in the movie the movement of the graphic elements are so fast that the movement looks stuttered/jerky. you could try increasing the shutter angle to 720 just to test to see if that makes those portions smoother.

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW

[Shawn Marshall]

Hi:

Thanks for all of the replies; I really appreciate you all taking the time to help.

The frame rate is essentially constant in the Get Info window in QT player. It holds steady at 30fps, very occasionally dropping to 29fps for a fraction of a second, but those drops don’t correlate to the stutters I’ve been experiencing.

I did try upping the shutter angle from 180 to 360, but that didn’t really help. I added a slight blur to some of the elements, and that might have helped a bit, but I’m not sure.

Since this is playing off of a laptop into a projector I’d rather not interlace this piece.

The piece uses only one video clip, and it’s compressed with the ProRes HQ codec (the video clip appears in a different section than those that stutter.)

I’ve found that the animation actually seems to play smoothest when I play it full screen. Not perfectly, but better. The frustrating thing is the location and intensity of this stutters varies slightly each time the piece is played. One time it will be almost perfect, the next there will be stutters here and there.

The stutters do occur on different computers. Again, the intensity and timing vary a bit, but can generally be correlated to when a certain block of text and screen capture start to slide in from the right.

I’m rendering out the finals now, and will then compress that to a 1280×720 h.264 QT for the deliverable. I’ll keep you posted.

Thanks.

Shawn Marshall
Marshall Arts Motion Graphics

[Shawn Marshall]

Hi:

Thanks for the reply. The final animations, compressed with the Pro Res 4444 codec, are playing off an internal RAID 0 array which can handle the 30MB/sec data rate at 1080p with no problem. And the artifacts sometimes manifested themselves during a RAM preview and at smaller sizes, codecs, and data rates, so I don’t think it’s a hard drive issue. I think it’s a video card issue. My Radeon HD 2600 card is feeding two monitors.

I’ve outputted the final animations and compressed them in Compressor as h.264 QTs with 6000k-8000k data rates, and they play pretty smoothly, especially at full screen. The stuttering seems worse when played within the Quicktime window. The h.264s also play pretty well on our Mac Mini hooked up to our HDTV (Mini-display port to HDMI).

So who knows?

Shawn

[Keith Kyak]

Hi Shawn,
Just wondering if you came up with a solution to your issue?. Im having the same issue and its driving me nuts…similar animation: a left to right movement with a bit of a diagnal angle gives me a very jerky playback..tried fields, tried playback from my HD_SDI monitor out of my AJA card…still jittery/jerky and also like your issue it happens at diferent places during playback, inconsistant….mo-blur and frame blending helped slightly but not enough…Playing back off of a RAID 5….
…Anyone?
cheers,
Keith

[Cory Ransom]

Over a year later and this still seems to be a problem (even with CS 5.5).

I just finished a project with L to R scrolling, no embedded movies, straight up 72 dpi jpg’s and AI vectors. Upon export the jumping and stuttering seems to happen randomly no matter the codec combination (All varieties of ProRes, Animation, Photo JPEG, H264, etc…). I have even exported a tiff sequence, re-imported the frames and baked a movie from that. I stop, rewind and re-play the same 60-90 frames and it doesn’t seems to happen with any consistency, only that it happens somewhere within that frame range.

Now, here is the real interesting part. This problem only seems to manifest itself through media players on the mac (vlc, qt, etc..). I haven’t tried a PC… If I re-package one of my 5994 H264’s for playback on a PS3, I don’t see the issue when played back from the PS3. Could this simply be a problem with the QT decoder?

In any regard, there should be some solution or workaround.

[Alik Griffin]

Hey Shawn,
Years have gone by since your original post but I thought I’d update my findings. I’ve had this problem for years. Animators would give me a panning shot of stills or comps, left to right, or right to left and it would always get these little jitter or skips.

I work for a game trailer agency and even some of our game capture that has smooth left to right pans or bullet time (when the shot is frozen in time) gives this stutter effect when encoded or brought into final cut. My only guess is it seems to be a codec thing. When I play it back ram preview in AE uncompressed, it’s always fine or better, the second I go to Final cut or any compressed codec like PRORES HQ or 444, dvcproHD it stutters. It always plays back better when using quick preview out of Finder and it plays especially crappy in the quicktime application. You can see a sample with this trailer. Check out the first shot: https://www.youtube.com/watch?v=1IJ4qLuyCqU

Here are a two things I’ve discovered that mildly help the problem for animation in AE.

1. Using the scrolling credits concept. Make sure the shots origin moves in a multiple of whatever your frame rate is. Or something like that.

You can use this expression on your position. Change rate to adjust speed.

rate = 6; //value in px/sec.
if (marker.numKeys > 0){
if (time > marker.key(1).time){
value – [rate*timeToFrames(time-marker.key(1).time),0];
}else{
value;
}
}else{
value – [rate*timeToFrames(time-inPoint),0];
}

It seems to help a little but not completely.

2. I know Perian was giving mac codecs problems awhile ago. Uninstall it. It helped me a little with stutter awhile ago.

3. Make sure your frame rates are consistent all around. 24 frames per second is not the same as 23.98. So if in AE you’re working on a shot that is 23.98 and your sequence is 24fps it could possibly generate very slight stutter problems.

My Conclusions:
I’m still stumped and am working on a project that is giving me this problem.

I would love to hear if anyones ever come up with a reason why smooth pans or dollies on still or almost still images creates a stutter.

I’ve tried a million things to try to vary pixels slightly, using lens warps, comping smoke, trying double frame rates before encoding. (So rendering out at 48fps and doing the final encoding at 24) Deflicker in FCP. Nothing seems to help.

I’m totally stumped and can only think that it’s a video playback issue that has to do with our 3d cards trying to decode the codecs. Or maybe a monitor refresh rate thing?

It always plays better in AE, and decent in and Finders quicklook. Everywhere else seems to generate a stutter. Especially going to H264. The strange thing is the stutter doesn’t happen consistently at the same spot. It’s variable stutter and is unique every time it’s played.

Alik Griffin
http://www.AlikGriffin.com

[Gaël Le Rudulier]

Hi Shawn, it’s been a few years again. did you find any solution to that problem? I’m experiencing the same here and can’t find a solution.