Luma or Chroma Key very very slow

_litz wrote on 11/19/2023, 10:02 PM

Build 187 version 21

Tried NVidia and Intel CPUs, various processors, various computers.
Tried with and without GPU acceleration (on both Intel and NVidia)

The INSTANT that I turn on any kind of luma or chroma key, I get single digit render speeds at any resolution using Magix AVC or HEVC.

I'm baffled. There is seemingly nothing other than "it's vegas" that makes this go slow.

If I set up the same chroma in Premiere or Resolv on the same hardware, the render flies.


RogerS wrote on 11/19/2023, 10:51 PM

What about using color corrector secondary to create the mask, is that any faster?

I don't see what is baffling- not all Fx are easy to process, and compositing multiple tracks is much more computationally intensive. Of course you'd keep GPU acceleration in in preferences/ video and if the Fx are CPU-limited you'd be better off with GPU encoding so the CPU isn't burdened with that, too.

Custom PC (2022) Intel i5-13600K with UHD 770 iGPU with latest driver, MSI z690 Tomahawk motherboard, 64GB Corsair DDR5 5200 ram, NVIDIA 2080 Super (8GB) with latest studio driver, 2TB Hynix P41 SSD, Windows 11 Pro 64 bit

Dell XPS 15 laptop (2017) 32GB ram, NVIDIA 1050 (4GB) with latest studio driver, Intel i7-7700HQ with Intel 630 iGPU (latest available driver), dual internal SSD (256GB; 1TB), Windows 10 64 bit

VEGAS Pro 19.651
VEGAS Pro 21.108

VEGAS 4K "sample project" benchmark:
VEGAS Pro 20 "Ad" benchmark:

Gid wrote on 11/20/2023, 3:51 AM

For me it's all Project size dependant, (There's multiple chromakeys on the green screens + Charcoal to create the edge effect (Glow from Track motion), & at the bottom there's an assortment of AVC, HEVC & MOV/ProRes, I see no slow down when rendering through the different formats.)

HD 1920 x 1080 renders quite fast & steady

UHD 3840 x 2160 slows down by about ½ but is still steady & acceptably fast enough.


Vegas Pro 21 
Magix Movie Studio Platinum 2024 - from 2004-ish - Latest version,
Magix VPX14
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Mocha Pro Standalone + Plugin, 
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(programs on one, project files on the other)
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I'm 55, I've been a UK joiner for 39yrs, apprentice trained & time served, I make videos about my work & post them on Youtube so that I can share what I've learnt over the yrs,

At the moment my filming is done with a Samsung Galaxy S23 Ultra 

_litz wrote on 11/20/2023, 11:42 AM

No, none of the above appear to apply. I'm using 21 with the brand new build 187.

It runs "normally" for about 10 seconds, then drops to a crawl, like it's run out of memory or exhausted a disk buffer.

This happens independent of PC, graphics card, or any settings you can think of (HEVC, GPU, etc).

It's just broken, and I cannot figure out what is wrong.

The instant I render without chroma, speeds are normal.

All it takes is literally a single element with chroma added -- only one track. And renders are single digit speed.

And like I said above, the same exact process (single track, single chroma) in Resolv or Premiere runs without issue.

_litz wrote on 11/20/2023, 12:06 PM

As a followup, might have found a solution by setting up my chromakey in 1 project, then loading that project directly into another project (so it in effect frameserves). That renders without delay or slowdown.

So the issue isn't the chroma itself, but the processing that happens while rendering.

And yes, I've tried multiple different rendering formats. Same result.

This is not, it goes without saying, the way it's supposed to work, nor is it the way it's worked in the past.

Todd-A0 wrote on 11/20/2023, 5:55 PM

I don't really see much of a difference, and no great change with CPU or GPU use, is your GPU or CPU maxing out with chromakey?