TOPIC:

Hello. New here, though I've been using Final Cut since 6 or 7. I've recently purchased a new computer. It's a lovely 16" MacBook Pro with a 2.3gb 8 core I9 inside it. I have 16gb or RAM and a Radeon 550m with 4gb onboard video RAM. This thing should be an absolute powerhouse for video editing. Here's my problem:

I'm trying to cut footage of a long video in half. The original is a 1080p 60fps video, approximately 4.5 hours in length. The new file is 2.5 hours. I've already successfully exported the first half, which I began before bed and it took well into the afternoon to complete the next day. This file has been exporting for 20 hours and is still only at 76%. I'm exporting in h.264 better quality. When I check the activity monitor, it says FCP is using 7.5% of the CPU and a shocking 2.65gb of RAM. This thing is going to take, at this rate, 26 hours or more to export a 2.5 hour video file and it's not even making proper use of its resources.

Could someone please tell me what I'm doing wrong? Because this is no way to split of your Twitch VODs into YouTube videos!

Well, exporting is not a RAM intensive operation, and if you're exporting H.264 or ProRes your system is probably using more GPU than CPU to do that. So don't sweat those numbers.

The first thing I'd do is select the Library, go to the File menu, Delete Generated Library Files, and delete ALL render files. Then go to Preferences and turn Background Rendering off, and never turn it back on ever again.

What is the codec of your original files that you're editing with?

I have searched all over the Internet for a useful answer to this question. And all I see is wise guys coming up with answers that basically blames the victim.

Across several machines and several projects I have established as a fact that FCP (latest version) does not make use of a sensible amount machine resources when exporting a H264 project from a project with similar source material.

As someone has noted, exporting takes days not hours. And no, there is nothing wrong with any of my machines, they both use GPU and CPU and has more than enough RAM thank you very much.

Anyone who has experienced similar woes - have you found a solution?
I haven't tried converting the timeline 264 to ProRes before importing, but this is 2022 and if it was necessary FCP would probably do it internally.

"I have established as a fact that FCP (latest version) does not make use of a sensible amount machine resources when exporting a H264 project from a project with similar source material."

This is not a widespread issue, so it's logical to conclude that it has something to do with an individual's installed software or some other bottleneck that hasn't been considered.

I get the irritation with dismissive answers, so maybe we can dig a little deeper here if you're willing.

Easily Trimming Video Files with Quicktime Player

paalar wrote:

...Across several machines and several projects I have established as a fact that FCP (latest version) does not make use of a sensible amount machine resources when exporting a H264 project from a project with similar source material....As someone has noted, exporting takes days not hours. And no, there is nothing wrong with any of my machines, they both use GPU and CPU and has more than enough RAM thank you very much...

In general on a recent generation Intel or Apple Silicon machine, FCP exports very fast from an H264 timeline to H264 output -- provided you use an optimal export preset. E.g, a fast method is File>Share>Export File>Settings>Format>Computer, and pick
Video Codec: H.264 Faster Encode
Resolution: 1920 x 1080 or 3840 x 2160

It is not necessary to pick "Better Quality"; the fast export is visually almost identical. The machine need not be the absolute latest, although Apple Silicon is often faster. Even a 2017 i7 iMac 27 can export relatively quickly.

That said, export consists of two conceptual phases: rendering and encoding. If the timeline is not rendered and if it contains many compute-intensive effects such as Neat Video, the render phase will take a long time, even if the encode phase to H264 is fast.

You can determine if the problem is render time vs encode time by duplicating the timeline, open it, select all clips with CMD+A, then remove all effects with Edit>Remove Effects, then do a timed export of that. If it is much faster, it's an effects problem. If it's the same time, it's an encode problem.

Re FCP not making use of machine resources, it generally uses those very efficiently. There might be some cases with a Motion effect whereby the Motion runtime engine or a 3rd-party plugin is not sufficiently multi-threaded. If you can post more details, we'll be happy to help.

Re the previous poster who in 2020 complained he only wanted to split a 4.5 hour video in half and FCP was slow, he could have done one of two things:

(1) Instead of exporting a 2.25 hour video using FCP using "Better Quality" H264, he should have used "Faster Encode". That would have been much faster and visually about the same quality.

(2) He could have used Quicktime Player to split the file in about 5 seconds (vs 26 hours) without re-encoding. That would have been about 19,000 times faster. See the Macmost episode "Easily Trimming Video Files with Quicktime Player":
Easily Trimming Files with Quicktime Player

I'll only export h264 at the end of the gig. ProRess 442 for me renders out on at around 1 minute export per 1 minute of timeline with h264 being maybe 4-5x that. ProRes to Bluray disc mastering is also vastly quicker. I'll only run h264 at the end of the project to keep file size more manageable or for archiving but all around the schoolyard it's working in ProRes that keeps things snappy on export or disc mastering when delivery time is a primary concern.

I have done some tests.
It is absolutely true that a 264 export from a timeline with 10 bit V-Log 264 longGOP with some effects renders at roughly 1/40 speed, checked on 2 machines, Intel and Mac Silicon. The reason for this is opaque as ActivityMonitor shows very low activity - 20-30%CPU/GPU almost no disk writes and a reasonable memory usage.

HOWEVER: When transcoding the timeline to Prores HQ, the speed increased by a factor of 20 for the same h264 export.

And the CPU/GPU utilisation increased to sensible values.

This is IMHO something developers should look into.

This may be a problem specific to a set of software that produces the problem, as joema’s performance results seem more typical with H.264 in and out on recent Intel and M series systems.