Performance Color corection

[IgorY]

Very slow rendering if color correction (LUT) is used.
In fact, only one processor core is used. Can something be done? Eight-minute video (HD) in an hour only 30% is ready

[lata]

Need a little more info
I ran a quick test using 8 minutes of MTS video 1920 x 1080
Applied the Black and White lut profile.
Share -- Same as First Clip to retain the original properties and quality.
Quite slow to render although progress seemed steady, completed in 32 minutes
My pc specification shows to the right, not the fastest of machines, I am sure others should do better with render times. CPU Video Studio running at 40% + ( all 4 cores)
Oh, using Video Studio 2023

[asik1]

Never used LUT so I join for the test. I trimmed to 5min a ~16Mb/s FHD mts file I just shoot today with sepia LUT
First run "Same as First Clip" was crazy, 4 cores at 90% , temp was 75c ... 5:00 min came to be 6:07 long m2t file and took ~7min to render. WHAT...?
looked at the processes and found stuck player app hanging the cpu at 50%. Killed it and re-run

Second test, "Same as First Clip" , 2 cores ~70% 2cores ~25% , temp was ~67c . 5:00 min came to be 5:59 long m2t file and took ~9min to render.
WHAT...?

So I reboot, running just VS2023 for 3'rd test, now I went for 15Mb/s mp4 file
2 cores ~70% 2cores ~25% , temp was ~67c . 5 min came to be ....... 5:00min mp4 file and took ....~9min to render.

There you have it all
from that I guess 8min will take ~14.5 min to render on my 6 years old system.
* I never render to m2t before so I can't comment on it's "misbehave".

my2c.

[zaphodikus]

Yep. Recently I started applying LUTs, and even found a few interesting ones and also found the "strength" slider on the LUT colour page, and found it almost doubled my render times. Almost, but yes has significantly slowed. I have to admit, the Colour correction was never my thing, but I'm taking my hobby more serious lately, but back when I have used to use the newblue colour correction filter, I also found performance was not brilliant either, but I was still new to colour back then, so I stopped using the filters so much for a while. But still worth it because it is easy when you only have 3 or 4 LUTs that you really like, to quickly just tweak all your clips after all your edits and hit "go". Even if it does almost double the render time. (I have a load of free cpu cores so I normally happily play puzzle games while the renders run.)