Color Banding

[Mike]

Hi,

I'm preparing some video material for a show and am seeing color banding on my MacBook Pro (16-inch, M1 Max) monitor when running the show in QLAB, but not when viewing the same files in QuickTime Player. The files are Apple ProRes 422 (10-bit). I've attached an A/B comparison. (Note that I've increased the contrast in photoshop to make it more obvious.) A few questions...

 Does QLab 5 work internally at 8-bit? 

I'll be outputting the video through the MacBook Pro's HDMI port to a Blackmagic ATEM switcher before it goes to the LED wall. Should I expect that to also be 8-bit / have color banding? 

If so, is there a some way of outputting 10-bit or higher images from QLab, such as going out via Thunderbolt to a 'Blackmagic UltraStudio HD Mini' and then HDMI from there?

Thanks,

Mike

[Siobhán Dougall]

Hi Mike,

You’re correct that QLab currently uses an 8-bit video pipeline internally. We’re hoping to add support for higher bit depths at some point, but in the meantime, if you’re able to encode your video files at 8-bit with dithering applied, that will help prevent the banding (including the narrower banding that is still visible in QuickTime Player).

Cheers,

Siobhán

--

Siobhán Dougall (she/her)

Software developer, Figure 53

sio...@figure53.com

https://qlab.app/

Thanks,

Mike

<Color-Banding.png>

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<Color-Banding.png>

[Adam Straus]

Apologies for reviving a dead thread, but I'm wondering what the recommended color/codec workflow is for QLab, since various flavors of ProRes are what is recommended in the documentation, but ProRes is always 10-bit.

[Ben Estabrook]

Hi all,

I'd like to also voice support for a 10 bit or higher color pipeline in QLab.  I use QLab for film screenings and occasionally films come in with very subtle tonal shifts and minimal noise/grain, which results in banding/posterization when played in QLab.  In the case of film screenings, it doesn't seem appropriate to add in grain/noise/dithering since that would be at odds with the filmmakers' vision, so I'm hoping we'll see 10 bit support in the near future! 

thanks,

Ben

[Greg Leeper]

I too vote for 10 bit - as I've been using it on screenings as well....    and want it to look as good as it can!

Thanks,

Greg Leeper

[Ben Estabrook]

Hi Siobhán,

It has been a while since we have received a status update on the implementation of a 10 bit pipeline in QLab.  I know you all are a small team and have to prioritize your resources, but 10 bit support should be at the top of the list.  As it is now, QLab is the weak link in the video chain:

Video camera (10 bit) > ProRes video (10 bit) > QLab (8 bit) > MacBook Pro HDMI out (10 bit) > Projector (10 bit)

In 2025, this simply is not acceptable for professional software.  Modern Macs with Apple Silicon have more than enough horsepower to process 10 bit video in realtime.  Please let us know when we can expect to have this critical feature added to QLab.

thanks,

Ben

[Chris Ashworth]

Hi Ben,

We agree; support for 10 bit video is also at the top of our list.

Thanks,

Chris

[Ben Estabrook]

Hi Chris,

That is fantastic to hear.  Thanks for letting us know, and I look forward to the QLab update!

cheers,

Ben

[Alex Huber]

This is great to hear. I agree that having a 10bit pipeline in 2025 is absolutely necessary.

Alex