Recommended specs for 8k

Just out of curiosity, I wanted to know what is the recommended power to run shotcut in 8k?

I am not going to work in 8k right now, and I don’t think of working until shotcut is optimized.

Do specs matter much if using proxies?

Obviously, great videos comes heavy proxies (don’t truly know about).

Just matched to “Great power comes great responsibility”. So I wrote it.

We could say that with heavy source videos come heavy transcoding times to make proxies. But proxy performance and file sizes after that are equal to any other source resolution.

In that sense, if using proxies, Shotcut is a decent 8K editor as it is today.

As for final processing and export, all the usual performance variables remain the same. It depends on the filters used (are they single or multi threaded?) and depends on the codec used (does it thread well or support hardware encoding?).

If using hardware encoding or an intermediate codec, then 8-16 fast cores are generally faster to export than 16+ slower cores. If using libx264/265 or SVT-AV1 with high-quality tuning and presets, then 16+ slower cores might outrun 8-16 fast cores simply because those codecs thread well and can efficiently use the extra cores.

If the goal is to edit 8K without proxies… it might be possible for simple cutting on one track. I would expect performance to fall apart the moment multiple tracks get involved or the first filter gets applied. That’s a lot of math to do by CPU alone.

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I have a few 8k videos from my phone (7 680 x 4 320 pixels, ~80mbps 23.976fps but sadly variable framerate, mediainfo reports minimum of 4fps and up to 24), these are just some tests I shot at the begining when I thought wow 8k, so cool, then realised it’s not only completely useless but also 4K looks better (as in the dynamic range is very obviously better and I can choose 30/60fps, 8k is fixed to 24fps on my phone).

Did some quick tests on my desktop pc (cpu: ryzen 7 2700x), 8k in a 1080p timeline, quite fluid, actually playable - I think it shows at least half the frames, can even play (very choppy) with a colour grading filter applied. In a 4k timeline it is still acceptable, about twice as choppy as the 1080p but I could work with it.

Now 8k videos in an 8k timeline is just another level of horrible, I’d say there’s 3 frame updates per second and feels like a sloppy slideshow. Shotcut was actually pretty stable, no crash or hang at all of the interface during the test. RAM usage got ridiculous tho, I have 5 files in the timeline totalling 3m50s and it is using 13GB RAM, it started at 4GB and instantly goes up 2 GB every time I seek on a new file.
Exporting at 8k24fps with x265@crf25 uses 95%CPU and 12GB RAM alone, and for the 20s mark I selected it took over 7min (in 1080p the same 20s part took exactly 40s).
Interestingly, my GPU doesn’t support 8k (it’s a 5year old gtx970 so it’s expected) and the export fails after a few % so I don’t know if a GPU would render it in a decent amount of time.

I don’t know what the recommended specs would be but I don’t think smooth playback is possible without some form of hardware acceleration, I’d assume you’d get acceptable (so over 15fps) with a 16 core CPU that can do at least 4.5GHz (with good cooling) and 64GB of ram for short projects (<10min).

For the minimum specs I’d say any recent (last 2 years) mid-high desktop CPU can do it, minimum 16GBs of ram and a lot of patience.

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I do have a Intel® Core™ i9-10900X X-series Processor (19.25M Cache, 4.50 GHz) with 256 GB Ram and a single GeForce GTX 1660 SUPER with RTX 3090 on msi creator X299 motherboard, which I gave to my nephew for his course’s. Is that sufficient for 8k by your thinking? I can take it back and buy a new one for him.

This CPU is quite cheap compared to other i9s in the market.

I can take it back and buy a new one for him.

Maybe taking it back is a bit too much, he’ll be pissed :laughing: but you can have a test run on it. That sounds like a beast of a desktop, how did it end up with 256GB of ram? Is it used for some advanced computations?

The problem with cpu GHz is that intel/amd like to boast about their Turbo Boost speeds which are slightly misleading, what I mean is the top 4.5GHz clock speed is only reached in a single-core usage scenario, and only for a very limited time as it’s basically overclocking it temporarrily and even a good water cooling setup can’t keep it below the maximum temperature for more than a few minutes.
For my cpu it’s at 3.7GHz baseline and turbo to 4.3GHz, I only see a peak of ~4GHz during normal multi-core usage and it drops to 3.8 at 100% load. 8K editing will definitely use all cores so expect a real cpu frequency of around 4GHz which would not be a pleasant experience, but could probably work for a very short edit.

If you give it a try I’m curious if it matches what I assume above. I know GHz is not everything in a CPU and maybe the technology advancements make it 50% better than my old Ryzen so you’ll have a way smoother experience than me.

It will not make him pissed, I would gift him a mac pro (256gb) in return, I already ordered one for him because of his b’day.

Nothing like a beast, yes it has crazy specs, but because it was self assembled by me, I didn’t do it right, I have now to go through repair store and make it a healthy pc. I just got the ram when I bought the motherboard, it was from a supermarket in prayagaraj (Indian city) while Christmas (I found it out after 1 year because I putted it in the store room and then forgot). But it would be really a beast when it would reassembled correctly.

I will definitely do that.

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Quick Update!

I tried it, the experience was really smooth, the preview scaling was set to highest resolution and no proxy was there, the video played normally and scrolling was fast while editing the video, however, it takes sometime to export if the RTX 3090 is not there, otherwise it’s good and enough fast to make me happy. Exporting a 12 mins video takes around ~40 mins in the RTX 3090.

I don’t know much about the CPU, because I didn’t open the task manager at that time. But to my surprise, he actually rebuilt the PC (correctly!?!) with a new case. That literally shocked me up. How a 13 year old could do that?

I remember it was using around 24 GB ram.

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Very nice and impressive, thanks for the update.
He probably found some clips on youtube explaining how to build a pc and actually followed the advice, pretty cool.

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