EnableVideoInput/EnableVideoOutput faild

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  • Posts: 1
  • Joined: Fri May 20, 2022 9:56 am
  • Real Name: Nikita Dedov

EnableVideoInput/EnableVideoOutput faild

PostFri May 20, 2022 10:43 am


I am working with legacy code for frame capture. I face strange behavior, on calling EnableVideoInput or EnableVideoOutput it fails. DoesSupportVideoMode return bmdDisplayModeSupported. I tried which code from examples and it fails the same.
I tried two different cards Quad first 4 devices works well as input and as output, 4 last do not work. For 8K first works well, other 3 do not work. When I try to get more info about errors with _com_error but it say nothing. do you know what could be the reason of it?

Workflow is almost the same as in the example. one difference, we use IDeckLinkConfiguration to set params such as bmdDeckLinkConfigVideoInputConnection set to bmdVideoConnectionSDI, bmdDeckLinkConfigUse1080pNotPsF, bmdDeckLinkConfigVideoOutputConversionMode, bmdDeckLinkConfigHD1080p24ToHD1080i5994Conversion, bmdDeckLinkConfigVideoInputConversionMode etc. some of it fails when we try to set it, but what we can set we write to configuration.

Thank you

Cameron Nichols

Blackmagic Design

  • Posts: 391
  • Joined: Mon Sep 04, 2017 4:05 am

Re: EnableVideoInput/EnableVideoOutput faild

PostFri Jun 10, 2022 6:06 am

Hi Nikita,

It is likely that the DeckLink Quad 2 and DeckLink 8K Pro is configured with a device profile such that the EnableVideoOutput/EnableVideoInput is occurring on a device that is currently inactive.

I suggest running the DeviceStatus SDK sample to see whether the device is configured as full-duplex, half-duplex or inactive.

On the DeckLink Quad 2, to access all connectors independently you will need to configure each duplex pair as 2 sub-device half-duplex profile

On the DeckLink 8K Pro, to access all connectors independently you will need to configure the card as 4 sub-device half-duplex profile

Please see more information about the device profiles in the DeckLink SDK Manual, section 2.4.11. You can either configure the profile with the Desktop Video Setup application in the Connectors setting, or with the ActivateProfile SDK sample.


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