[FIXED] Moho Pro 12 - Sub-Frame Motion blur glitch

[Pierre Gombaud]

UPDATE 2: (after 12.1 update)

The problem is fixed! No more trouble with sub-frame motion blur on bitmaps.
It is still bugged when sub-frame motion blur is applied to imported 3D obj and shape layer converted to 3D.
I hope it will be fixed in a next update, as the potential is huge in my eyes. Good job, guys!


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So, I've got a character made of bitmaps (single .PSD with layers imported individually), with smart warps for deformation and bones.
When I add no motion blur or basic motion blur, there is no glitch when I do export to video (on Windows 10, H264-ACC).
But, if I enable sub-frame onto motion blur, the face is completely messed up.

Here is a video to show you the results, with these differents motion blur settings:
https://3.sendvid.com/kk81xgmi.mp4

I can provide the .moho file if needed.

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UPDATE:
I tried to render without "Multi-threaded rendering" and no more glitch.
But the render time is way longer, obviously...

If I render with "Multi-threaded rendering" enabled and in a JPG image sequence,
it is still bugged, but the output is even different! Weird.

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My computer: MSI MS-1781 - GT72 2QE (laptop)
GPU: nVidia GeForce GTX 980M (mobile) / drivers: 369.09 (old drivers, I've updated to 372.54, rendering is still bugged).
DirectX: 12.0 / OpenGL: 4.5.0 NVIDIA 372.54 (# ext: 385) / OpenCL: 1.2 CUDA 8.0.0
CPU: Intel Core i7-4980HQ (Crystal Well) @ 2.80 GHz / drivers: 10.0.14393.0 (Microsoft) (seems to be the latest version).
RAM: 32GB DDR3 @ 798.14 MHz (4x Kingston 8GB)
OS: Windows 10 x64 Family Edition - Build: 14393.51 (the last update, I think)

[ulrik]

I found the same glitch, bug, on my Moho 12 running OS X
I have reported it as a bug but that was with my computer specs , maybe you should do it as well!

Regards Ulrik

[Pierre Gombaud]

Ulrik, I've updated my initial post since, as there is a workaround, if I export with "Multithread rendering" disabled, the glitch is gone.
Downside is rendering time takes ages... I guess the problem might be related to the CPU?

I've send an e-mail to support.smithmicro.com

[synthsin75]

Certain features, like motion blur, that have to take each frame into account, in order, are not likely to work with multi-threaded rendering, since it divides up the frames between different CPU threads.

[ulrik]

Ulrik, I've updated my initial post since, as there is a workaround, if I export with "Multithread rendering" disabled, the glitch is gone.
Downside is rendering time takes ages... I guess the problem might be related to the CPU?

I've send an e-mail to support.smithmicro.com

Yeah, I've noticed that it renders okey if multi-threading is disabled but is it really that way it's supposed to be?

Synthsin, you said "certain features" is being affected by the multithreading render, can you tell me more?
What features?

[Pierre Gombaud]

Certain features, like motion blur, that have to take each frame into account, in order, are not likely to work with multi-threaded rendering, since it divides up the frames between different CPU threads.

That totally makes sense. But wouldn't it be possible to, say, calculate the frames on 3 cores and do a final "pass" for the motion blur on the last core?
Then we can at least use 3 cores, the last one being used solely for the motion blur. As you can imagine, I'm not an engineer

[synthsin75]

Certain features, like motion blur, that have to take each frame into account, in order, are not likely to work with multi-threaded rendering, since it divides up the frames between different CPU threads.

That totally makes sense. But wouldn't it be possible to, say, calculate the frames on 3 cores and do a final "pass" for the motion blur on the last core?
Then we can at least use 3 cores, the last one being used solely for the motion blur. As you can imagine, I'm not an engineer

Not as far as I know, because the motion blur has to be composited into each frame as it is rendered.

[Pierre Gombaud]

the motion blur has to be composited into each frame as it is rendered.

From my tests, I can use multithreaded rendering with subframe motion blur on vectors without any problem/glitch/bug, so motion blur can be composited this way?
It is when I use bitmaps instead of vectors that I get some terrible results.

[Pierre Gombaud]

UPDATE 2: (after 12.1 update)

The problem is fixed! No more trouble with sub-frame motion blur on bitmaps. Even with "mutli-threaded" activated.

It is still bugged when sub-frame motion blur is applied to imported 3D obj and shape layer converted to 3D.
I hope it will be fixed in a next update, as the potential is huge in my eyes. Good job, guys!