OpenCL HA Nvidia implimentation bug on some GPU's

JL_JL

Senior Contributor Location: Arizona, USA Joined: Oct 01, 2006 20:01 Messages: 6091 Offline

Solved by

Sep 30, 2015 21:56

Another implementation bug that appears to affect some platforms and some GPU's. To replicate:

1) Simply place the Kite Surfing.wmv in the timeline
2) Apply the Gaussian Blur effect to the video clip (I had it in my "Favorites" in video demonstration)
3) Toggle OpenCL on or off in PD pref > Hardware Acceleration
4) Total image distortion as one moves the scrubber

The issue does not affect all Nvidia GPU's. In the attached demonstration video the issue was shown on a GTX970, 355.82 driver. A "Produced" file has the bad distortion of the Gaussian Blur effect when OpenCL is utilized.

Jeff

Filename	Capture_4.mp4	Download
Description	OpenCL Bug
Filesize	16323 Kbytes
Downloaded:	167 time(s)

optodata

Senior Contributor Location: California, USA Joined: Sep 16, 2011 16:04 Messages: 8630 Offline

Oct 01, 2015 00:18

Julien Pierre

Contributor Joined: Apr 14, 2011 01:34 Messages: 476 Offline

Oct 01, 2015 00:47

Interesting. Good to know that some effects are actually utilizing the GPU.

If you encode with the software encoder, does OpenCL on the GPU still get utilized for the effects, and do you see the distortion still ?

If so, I would be interested in seeing the amount of GPU utilization for that rendering. MSI X99A Raider
Intel i7-5820k @ 4.4 GHz
32GB DDR4 RAM
Gigabyte nVidia GTX 960 4GB
480 GB Patriot Ignite SSD (boot)
2 x 480 GB Sandisk Ultra II SSD (striped)
6 x 1 TB Samsung 860 SSD (striped)

2 x LG 32UD59-B 32" 4K
Asus PB238 23" HD (portrait)

Dafydd B

Senior Contributor Joined: Aug 26, 2006 08:20 Messages: 11973 Offline

Oct 01, 2015 05:55

Hi JL_JL,
The bug information (your post and video) has been passed onto CyberLink for them to replicate.

Dafydd

JL_JL

Senior Contributor Location: Arizona, USA Joined: Oct 01, 2006 20:01 Messages: 6091 Offline

Oct 01, 2015 09:18

Quote: Wow, that's ugly. No issues with my 780Ti w/355.98. Also no issue in PD13 with boats.wmv. OpenCL on or off work as expected.

As I said "some GPU's", my GTX650 does not have the issue either. And yes, the issue does affect PD13 too. Again, certain GPU's, appears to be newer GPU's, 3 different GTX9xxx series for me have the issue.

Jeff

This message was edited 1 time. Last update was at Oct 01. 2015 09:30

Bhajje

Senior Member Location: France - Orléans Joined: Feb 06, 2011 11:30 Messages: 176 Offline

Oct 01, 2015 09:27

I can replicate this issue with my GTX960, driver 355.98, and Open CL checked. Jean-Paul

i7-4770K 3.50 GHz, Nvidia GTX 960 2 Go, SSD 500 Go, RAM 32 Go
Win 10 64 bits, DirectorSuite 365

JL_JL

Senior Contributor Location: Arizona, USA Joined: Oct 01, 2006 20:01 Messages: 6091 Offline

Oct 01, 2015 09:28

Quote: Interesting. Good to know that some effects are actually utilizing the GPU.

If you encode with the software encoder, does OpenCL on the GPU still get utilized for the effects, and do you see the distortion still ?

If so, I would be interested in seeing the amount of GPU utilization for that rendering.

Any effect that has the GPU brand symbol in the left corner does use the GPU and always has if OpenCL is selected. Yes, CPU encoding with OpenCL checked will result in the distored "Produced" video. CPU encoding without OpenCL checked will result in the proper blur applied in the "Produced" video.

Jeff

Julien Pierre

Contributor Joined: Apr 14, 2011 01:34 Messages: 476 Offline

Oct 01, 2015 10:41

Quote: I can replicate this issue with my GTX960, driver 355.98, and Open CL checked.

Same here with GTX 750 Ti and the same driver. MSI X99A Raider
Intel i7-5820k @ 4.4 GHz
32GB DDR4 RAM
Gigabyte nVidia GTX 960 4GB
480 GB Patriot Ignite SSD (boot)
2 x 480 GB Sandisk Ultra II SSD (striped)
6 x 1 TB Samsung 860 SSD (striped)

2 x LG 32UD59-B 32" 4K
Asus PB238 23" HD (portrait)