OBS Studio 27 Release Candidate

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About 1/2 the time on Track matte transitions I’m getting a flash frame of the next scene before the stringer element starts. It’s across the board on all of my track mattes(6 of them)
The other 50% of the time they are excellent!
Can you post a demonstration video of the issue, as well as a sample track matte that this happens with?


New Member
Hi everyone,

I have some issues running OBS (not only the RC1) on my iMac (Retina 5K, 27-inch, 2017, 4,2 GHz Quad-Core Intel Core i7, 40 GB 2400 MHz DDR4, Radeon Pro 580 8 GB)

The CPU usage is constantly rising up to about 275%, and OBS start to freeze for GUI inputs (face camera is still live, but starts to build up a delay). At this time the process kernel_task is starting to use a lot of CPU as well (over 300%). As soon as OBS is responding for GUI input again, the kernel_task is normal again, but the CPU usage of OBS still around 200%.

I don’t use any Browser-Sources in OBS due to the known issue with CEF. Instead I’m using NDI to transmit the content to another instance of OBS running on Windows. (There are the Browser-Sources).

I tried this 2 times and created a log file.
  1. try: https://obsproject.com/logs/Oz4mxK5avTBCXKq5
  2. try: https://obsproject.com/logs/LkMVT7MF22LOdrlm
At some point OBS suddenly drops down to 120% CPU usage (and the face camera is almost synced again), freezes and starts to build up CPU usage again.

I’m not using any window capture but screen capture instead.

(By the way, push-to-mute isn’t working either)


P.S.: If requested, I can provide an analysis of the OBS process from Mac OS. All scenes have been created with OBS 26.1.2
Last edited:


New Member
It was working here, but in version 26, when using the motion transition ("""zoom""" effect), it crashed, but in update 27 this bug was fixed!
Now I started OBS, it crashed before opening ...
Attached is a copy of the crash

*Ps. When I delet "profile" and "scenes" folders, it works again!

PLEASE, add gridline option in the preview window, to correct camera or objects angle/center!


  • log.txt
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I have the mistake of OBS saying it is recording, but it is taking a still image.
The picture is right, but the sound is right.

The funny thing is that the preview runs normally.

Use a ryzen 9 3900x with an RTX 2070

Its only the Game that doesnt get recorded.
Sound and Facecam work perfect.


Active Member
I didn't see this in release notes, but now able to configure my Blackmagic device (this didn't work in 26.1.1). Thanks whoever fixed that.
Can you post a demonstration video of the issue, as well as a sample track matte that this happens with?
here's the one of the files, but NOT limited to this one. Id say, over the last 2 days its been better, but still occasionally does it, ill try to record and catch it.
Also, cpu is up quite a bit across the board

Even though this is a different file, it’s the same behavior, I had my vods off; so I didn’t happen to catch the paint one .
You can see here, when I click the button we get a frame of the scene before the transition.

here’s a few of them, for S&g’z



OBS 27 rc2 crashes upon exit each time....
Please find crashlog and log attached.


  • Crash 2021-04-15 20-43-27.txt
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  • 2021-04-15 20-32-44.txt
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New Member
Hello, many players already have HDR monitors, many new games already support these functions. Are there any HDR capture support features planned for the next update?
Work in progress, is there any date?


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OBS 27 rc2 crashes upon exit each time....
Please find crashlog and log attached.
This crash is caused by the VLC source being unloaded twice. This could be caused by another plugin as indicated by <unknown>. Try it without third party plugins.

Hello, many players already have HDR monitors, many new games already support these functions. Are there any HDR capture support features planned for the next update?
Work in progress, is there any date?
HDR is planned, but not any time soon and there's no solid plan yet.
OBS 27, just like a few previous versions, include changes that will help the future development of 10bit (HDR) video. Small steps.



I have downloaded the 0.27 RC2 to my system and tested it. When I apply mask (alpha mask via filters) to my camera the picture becomes white washed. I have tried to change the opacity, but it doesn't have any effect to fix the issue.


New Member
With the RC2 my recordings and streams will randomly stop after anything from 5 minutes to 40 minutes(I've been testing this while just recording random work, that's the range I found, might be more or less) and restarting them isn't possible until I restart OBS completely.

This only happens when I enable the RTX denoiser on my mic. With the RNNoise denoiser this doesn't happen. This was reproducable on the latest Game Ready driver and on the one before that on my RTX 3090.

The log brings up the following just right before the crash:

19:02:22.835: error: Input contains (near) NaN/+-Inf
19:02:22.835: [FFmpeg aac encoder: '#someencoder#'] avcodec_encode_audio2 failed: Invalid argument
19:02:22.835: Error encoding with encoder '#someencoder#'

Kinda sad because the RTX denoiser seems to be working a bit better than the RNNoise denoiser.
Im not sure if this is by design or not.
When using a Browser Source to capture an Image (in this case a twitch user's profile picture 300x300.png)
the Matte Transitions wont play nice. I thought it was because of the square aspect ratio of the file. it seems like it is not.
Ive made 600x300 (double wide) to accommodate the proper aspect ratio of the .png file in question, and I still get a full rendering of
the track matte file (both the Alpha image and the Tack matte image) over the image being transitioned IN.
Ive tested with files that certainly work for scenes, and that are the same ones ive been using since RC1 for scene transitions, and that work on

I did a quick screen record----->
(this is with a browser source png)
this is with a local file jpg, same behavior. and as you'll see in the end, that transition works fine for scenes.
it would seem its Images, png, jpg local and through browsers.
regular WEBM stingers/reveals are working just fine

thanks guys!


New Member
I have a little weird issue with masks.

I apply a mask to a source in a scene... all good, source is not transparent - white background with checkerboard just to check transparency, it's of course disabled otherwise.


Then I nest the scene above into another one and it's suddenly transparent slighty:

This worked just fine in OBS 26. I triple checked everything, there are no filters or anything enabled.

Then I went and created a source mirror of the same scene and nested it and it's suddenly not transparent .... until I turn on the scale filtering (any) it gets transparent again.

So source mirror:

Source mirror with scale filter:



New Member
It actually happens without the Source mirror. So I apply a mask to a scene, nest that scene into another scene (regularily, without using the plugin) - and it becomes slightly transparent. I can try to uninstall StreamFX tomorrow and see if it still happens if that's what you mean


New Member
Hi everyone, I suggested "adding the grid line in the preview window" , and I came to show how I'm using ...
I thought of using it only in the preview window and not sending it to live for obvious reasons!
At the moment I made a 16:9 PNG image of the lines and trigger them by keyboard shortcuts. But sometimes I forget and sending the image with the lines over it.
I use them a lot to adjust frame live cameras, I think it will be of great help to many.
Would it be difficult to implement this?

PS. RC2 it's working here!

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