Dropped Frames - Blackmagic IO

[engineerfranko]

Since v22 of Premiere we have noticed that playback at 50p using Blackmagic results in dropped frames.

I have tested with all latest versions v23, v24 and including the Betas and reported to Adobe via their customer support but thought I should throw it in here as well as we have an upcoming project broadcast project where we must have the playback working. 

Couple of things to note:

1. The issue is not the IO device itself (tested with Ultrastudio 4K Extreme and Ultrastudio Monitor)

2. Only appears to affect 50p and not 25p or 50i.

3. It is not codec specific, same problem is in any codec

4. Rendering sequence, still playback issues

5. Tested with multiple versions of Desktop Video and firmware of devices.

6. Same files tested in BM Video Express, playback absolutely fine.

7. Machine itself is extremely high performance (2 CPU, 16 cores, 128GB RAM)

Our client has requested Premiere on the job so we can't ask them to use Avid. So a resolution is rather urgent even if it's beta.

[engineerfranko]

I should note also,

Deleting Caches didn't work

Turning off the Audio Hardware also didn't work.

[Bruce Bullis]

The BlackMagic Transmit plugin controls transmit output, and does not support all output resolution possibilities. 

What settings within the Transmit plugin (PPro --> Preferences --> Playback --> little gear next to BlackMagic plugin) are you using, when you see the 50p failure?

What version of the BlackMagic drivers are you using? 

How are you detecting dropped frames; PPro's "dog ears"?

[engineerfranko]

Hi Bruce,

In the Transmit Settings

Device: Artist DNxIQ

Colour Gamut: Rec709

No Output for unsupported frame sizes

Blackmagic Drivers 12.8.1 (also seen in 12.4, 12 and 11.5)

Drop frames are detected visually and the Premiere Pro output option 'Show Dropped Frame Indicator'

Turning off the Mercury Transmit, the playback is smooth but obviously only now visible in the GUI

[Bruce Bullis]

Ahh, the rebranded "Avid" Blackmagic device! Good details, thanks.


Also confirming: Only 50p has problems?

[engineerfranko]

So far as I can see, it appears the only issue.

I also saw the same problem with a TB connected Ultrastudio Monitor 3G so it would appear the problem lies in the sending of data to the BM.

I saw the dropped frames in the Dog Ears mode as well (love a diagnostic screen)

[engineerfranko]

[Bruce Bullis]

>...so it would appear the problem lies in the sending of data to the BM.

That doesn't necessarily follow; the problem could just as easily be in the plugin's handling of the data being sent. We'll have a look!

[engineerfranko]

OK, get ready for a whole load of weird on this one Bruce:

So, I open the project. The project is R709. I have media in two colourspaces: REC709 and REC2100.

Anything that is R709 plays with dropped frames: UNLESS - If I load a clip that is REC2100 into the Source Window, as if by magic we get a consistent 50fps playback. The software is then fine until quitting.

I have a screen capture showing it but due to security I won't be able to upload it here. Would you be able to email me on my account and I can send you the file for you to see?

[Bruce Bullis]

That IS super interesting! 

[I'll reach out directly, with contact info]

[Kevin-Monahan]

Hello @engineerfranko,

The product team has reached out and is helping you with the issue. Please let us know if you need further assistance or want to keep the report open.

Thanks,
Kevin

[Richard M Knight]

I've had this issue and I have just installed the latest BM desktop video driver

Makes no difference still dropping frames when using transmit.

Win 11

i9 9900K

64GB ram

BM Ultra Studio Mini 4K