Rendered animation stutters/jumps - how to fix?

V-Ray V-Ray Common Off-topic
1

Hello guys,
i always wonder when i see some archviz animation how smooth they are even if the camera moves very slow.
We always get the stutter OR jumpy movement after encoding.

Any idea why this is and how to fix this??
We render to 25fps and we encode with 25fps
We have plenty of camera motion blur in the scene (depending on the speed of movement) but that doesnt do the trick either.

Its like when you used to play games but your graphic card was not powerful enough so you get the FPS drops…

I am starting to be frustrated.

Could i please get some insight on how do you deal with this once everythign is rendered or prior to rendering?

Any help woudl be very appreciated.
Thanks!
M

2

I’ve experienced this too, would like to hear some opinions.

3

is the camera on a path?

4

nope, the camera just rotates its target so the result is a kind of a pan.

i ve done some intensive research on this problem on found out there is a RULE for panning saying:
The rule of thumb is to pan no faster than a full image width every seven seconds, otherwise judder will become too detrimental

so

there are some fixes to it such convert the footage to 60fps and use optical flow etc…we will be trying to fix this somewhat so ill post the result here :slight_smile:

5

If it’s jumpy like you say as in a video game with a budget gpu, then that to me says it’s a codec issue (though I haven’t seen codec issues in many, many years). Try uploading to YouTube and playback from there to eliminate this possibility

If you’re getting video tears, that often occurs due to moving the camera too fast - there are ‘tables’ and guidelines on how fast a camera should move within a scene (google them).

The alternative is to go for a higher fps rate. I’m in the UK and 25 is PAL, but I render at 30fps (NTSC). If I’m still seeing jumpy-ness, then I’d go to something higher, like 60, though this isn’t always practical.

6

yeah i know what you mean Jez, thanks!

We were very tight on render budget. Client insisted on 5 second interior pans :-DDD
It did not help to explain him that it will be too fast.
No way that i woudl render at 60fps if hes not willing to put more money in the rendering …i am not a sponsor at the end of the day.. :slight_smile: and FYI, one frame takes as much as 90 minutes on a 64 core machine :slight_smile: So 25 fps is as much as we can go here.
Nevertheless, making a scene in Davinci at 60fps, importing the 25fps footage in and scaling up the playback time to 5secs while using optical flow fixes the jumpy issue nicely and serves as a good technique for fast pans - when insisted on by clients :slight_smile:

7

I know exactly what you mean Martin !

I had the same issue, a client wanting an entire animation of a 300m cruiser ship in 30 seconds…

So much exterior features to cover, in such little time and of course, and the very tight budget in no way stretched to 60 fps :slight_smile:

Fortunately my frame render times were nothing like yours, though in my case, the Phoenix solution took forever :slight_smile:

Thanks for the Davinci technique, I’m not familiar with it or that software (I use Premiere Pro CS6), so will take a look.

8

Haha yeah i guess we all get this with clients :slight_smile:
you can do the same in premiere with optical flow. Let me know should you need any guidance :wink:

9

it does sound like codec issue. We had that problem with choppy video within app done in unity a while ago.

10

Any codec pack you recommend?
I thought codecs get automatically updated from within Premirere?

11

well you can check, just load the raw frames in to ram player. does it stutter?

12

Its a little better but it stutters still so it means the pan is just too fast for the fps.
i guess the 7 second rule has got some strong fundaments :slight_smile: