Choppy playback, but GPU is not being utilized

[loganr80794455]

So I have what I believe to be a decent 1080p editing setup:

AMD Ryzen 5 1600

GTX 1060 3GB

8GB DDR4 RAM

Adobe Premiere Pro 2017

Most 1080p videos will play fine, but when I speed footage up to a few hundred percent, the video is almost always choppy and drops many frames.  I have a yellow bar above every clip (whether I speed it up or not), and even if I render by clicking enter, the clip proceeds to play back just as choppy as before. This is odd to me because back on FCP, even if the footage couldn't immediately be played back after applying the effect, it would at least give me a loading screen, and then would be able to play fine after it had loaded.  Also, after a video has been exported, sped up footage plays just fine.  I checked a hardware monitor to see what was being maxed, and all CPU cores were sitting around 70%, but what was even worse is that GPU utilization is literally at 1%.  What can I do to get some help from my GPU? Thanks!

Note: I do have GPU acceleration (CUDA) activated.

[R Neil Haugen]

The GPU is used for GPU-accelerated effects, color things such as Lumetri, and re-scaling. Otherwise, not for much.

List of GPU accelerated effects: https://helpx.adobe.com/premiere-pro/using/effects.html

As to your rig, 8 gigs of RAM is barely enough for PrPro to function, and especially critical for this as decoding/decompression is mostly a CPU/cores/threads/RAM operation. You don't list your drives situation, but that's another area that can seriously kill playback.

Neil

[loganr80794455]

So it would make sense to sell my GPU and upgrade my CPU, plus add maybe 8 more gigs of RAM?  I originally built this PC for Da Vinci Resolve, which, from what I understand is much more GPU reliant.  I ended up liking Premiere a lot better, but it was too late by then.

[Jim_Simon]

after a video has been exported, sped up footage plays just fine.

That's what really matters.  Don't worry too much on how well it plays back on the timeline.

[yenaphe · Accepted solution]

Hi,

the issue here depends more on the type of source video you have than your GPU specs. As other have mentionned.

I'm guessing you are using h264 videos as source. This is the most common file format for HD content, but the issue when editing it, is that it's not frame based, but GOP based. What that means, is that, in order to compress the video, the codec won't encode every frame, but only 2 or 3 over one second of video. The in between frames are reconstructed by using complicated math that basicaly store moving pixel data.

The thing is, that decompressing these frames takes a lot of ressources. That's probably why your timeline is yellow and not green. Premiere have less difficulties to just plainly read frame base codecs (such as QT animation, or image sequences) than recontructing GOPs in GOP based codecs (GOP stands for Group of Pictures).

Knowing that, when you speed up your footage, Premiere will have to actually decode more GOPs in a shorter period of time, and that's where you will see your realtime playback drop frantically.

Premiere uses a lot of ram to store the decoded frames, and if you run out of ram, Premiere will have to trash the decoded frames and store the new ones. You can see how this can be a bottleneck quite fast.

What I would recommand to try, if storage space on your HDD isn't an issue, is to transcode the original clip you want to speed up into an image sequence or in a quicktime animation format. Then bring it into Premiere, speed it up, and see if your preview behaves better or not.

But as Jim said above, the most important is that once exported, your sped up footage works as intended.

Hope this helps,

Seb