15.1.0.023 smooth cut with alpha fails
Posted: Tue Sep 18, 2018 9:45 pmI have an ~8k clip that is 15s long and the "smooth cut" built-in effect is failing to render.
The grade has an alpha channel (for green screen key), also a parallel node with 4 inputs for resizing elements of the scene, for a total of 7 coloring nodes including 1 for NR. The timeline is 8k (7860x3840) to match the camera footage (Apple ProRes 422 HQ, 30fps). As soon as Resolve hits the effect in the timeline when playing I get a "GPU full" error message. The effect is within a compound clip.
I tried lowering the timeline resolution by 50% to 3930x1920 and turned off the NR node. Now the error message goes away and it renders (rendering in both cases at 1920x1080 to EXR with alpha), however the render is defective in that the information in the alpha channel gets corrupted during the frames where it hits the "smooth cut" effect (i.e. alpha goes to 100% white on those frames, losing my key).
Expect: Give me an error message if it is going to fail during the render. Better: just work. I understand parallel nodes and NR are GPU intensive however it's only a 15s clip and I have 2x 1080ti cards in this machine. And even with NR turned off (and lowering to 4k timeline resolution) it does not work. I don't have confidence a beefier machine will help since I understand GPU memory is not managed cumulatively. Would I do better to use another program for this? Workarounds most welcome if there is no fix on the way. Thank you!
System info: https://drive.google.com/open?id=1SP_2r ... 279qXrS5FK
Davinci log: https://drive.google.com/open?id=1-C6IC ... uKpDPEtjiu
The grade has an alpha channel (for green screen key), also a parallel node with 4 inputs for resizing elements of the scene, for a total of 7 coloring nodes including 1 for NR. The timeline is 8k (7860x3840) to match the camera footage (Apple ProRes 422 HQ, 30fps). As soon as Resolve hits the effect in the timeline when playing I get a "GPU full" error message. The effect is within a compound clip.
I tried lowering the timeline resolution by 50% to 3930x1920 and turned off the NR node. Now the error message goes away and it renders (rendering in both cases at 1920x1080 to EXR with alpha), however the render is defective in that the information in the alpha channel gets corrupted during the frames where it hits the "smooth cut" effect (i.e. alpha goes to 100% white on those frames, losing my key).
Expect: Give me an error message if it is going to fail during the render. Better: just work. I understand parallel nodes and NR are GPU intensive however it's only a 15s clip and I have 2x 1080ti cards in this machine. And even with NR turned off (and lowering to 4k timeline resolution) it does not work. I don't have confidence a beefier machine will help since I understand GPU memory is not managed cumulatively. Would I do better to use another program for this? Workarounds most welcome if there is no fix on the way. Thank you!
System info: https://drive.google.com/open?id=1SP_2r ... 279qXrS5FK
Davinci log: https://drive.google.com/open?id=1-C6IC ... uKpDPEtjiu