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[mattkhan]

https://github.com/3ll3d00d/ezcapture

This thread is about a variant of https://yabb.jriver.com/interact/index.php/topic,140134.msg972062.html which uses the decklink api to support blackmagic capture cards

it's in testing state atm but seems stable enough to try to use it, feedback welcome

current testing version can be found at https://github.com/3ll3d00d/ezcapture/releases/tag/0.7.0-alpha.9

pls use this variant for testing -> bmcapture-0.7.0-alpha.9-release-trace-logging.zip

as then logs are available

installation instructions, basically admin cmd and then regsvr32 the ax file (NB: rename it bmcapture-trace.ax if using trace)

a few things to note if you try it

* I only have a decklink mini 4k here so testing is a bit limited
* it converts everything to 8 bit RGB internally right now because it's the only format natively supported by jrvr (better transformations will come later)

[Hendrik]

ok thanks, is there a post somewhere that explains how to interpret the jrvr video timing log?

No, the log is basically designed for me. Although with the headers you can sort of make sense of it, i guess.
Note that its layout changes based on presentation mode.

[jmone]

Sounds good, I'll give it a try and report back!

[jmone]

Here is a quick test from my Camera (and I'll be away till the easter weekend).  I tried with both UHD/50fps 709 and HLG signals (see attached pics).  Here are some notes:
- Audio was just static that came and went (note: I was just sending 2ch from the Camera and the filter was saying 8ch)
- The filter seems to be "persistent" and holds the device till you close both MC and MC Server (otherwise you get a black screen in MC if the input signal changes between playbacks)
- 709:  Just worked and looked good
- HLG:  Just worked and looked good, I see that the Colour Format was 2020, but the Transfer function was 709 not HLG

Overall, nice work!  I'll try with a PC next.

[jmone]

Did a test from a Laptop playing and HDR Test Clip using MC so I could see that it was outputting HDR correctly.  The input was only seen as SDR.

[jmone]

Couple of other things:
 - the audio "static" thing, is actually over the top of any other audio, I even get it when the video is paused.
 - it is all a bit "fragile", in that if you get any signal mismatch you end up with a black screen (eg everything needs to be in the same FPS, and the BMD device seems to get stuck in a particular FPS).

[mattkhan]

thanks for testing, tbf I wasn't expecting stability at this point

can someone fork these posts to a new thread on a public board? I guess they're better there as they are about decklink devices specifically

- Audio was just static that came and went (note: I was just sending 2ch from the Camera and the filter was saying 8ch)

I was surprised by this also, the SDK reports the card has 8 channels so that's what I set the output format as but I thought capture was 2 channel only

- The filter seems to be "persistent" and holds the device till you close both MC and MC Server (otherwise you get a black screen in MC if the input signal changes between playbacks)

as far as I can see, MC never destroys the filter once it's loaded it until server shutdown which, to my mind, seems a bit odd. I would think the filter would be destroyed after playback stops (and hence the filter graph is torn down) but that's not how MC works as far as I can see. It seems a bug to me.

- HLG:  Just worked and looked good, I see that the Colour Format was 2020, but the Transfer function was 709 not HLG

will check it, I hadn't thought about HLG tbh (don't have any such sources)

Did a test from a Laptop playing and HDR Test Clip using MC so I could see that it was outputting HDR correctly.  The input was only seen as SDR.

for this case, it will be really helpful if you can use the trace filter and post the log it generates

[JimH]

CEO-Elect is Back:  https://yabb.jriver.com/interact/index.php/topic,141053.0.html

[mattkhan]

@jmone updated 1st post, there's a new build which hopefully fixes many of the issues you noted

[jmone]

Thanks mate, I'll give it a go when back home later this weekend!

[mattkhan]

just to note, the thing I haven't spent any time on yet is audio

[claw]

HDR input not processed as such.

Trace log attached.

DeckLink 4K Mini Recorder.   
Apple TV 4K sending 4K23 4:2:2 12-bit BT2020 HDR10

[mattkhan]

thanks, looks like a simple bug in propagating the hdr metadata

Should be fixed in https://github.com/3ll3d00d/ezcapture/releases/tag/0.7.0-alpha.9

[claw]

thanks, looks like a simple bug in propagating the hdr metadata

Should be fixed in https://github.com/3ll3d00d/ezcapture/releases/tag/0.7.0-alpha.9

I will test later today.

Another issue I did not mention is that motion is not smooth, especially with the trace version of the capture filter.  Switching to the non-trace version helped but still not good enough.   Using the same JRiver and JRVR options that I use with the Magewell card.

[mattkhan]

Is it dropping frames?

[claw]

No.

[claw]

thanks, looks like a simple bug in propagating the hdr metadata

Should be fixed in https://github.com/3ll3d00d/ezcapture/releases/tag/0.7.0-alpha.9

Getting unable to lock status in log.

User error.

[mattkhan]

I have found it flaky in that regard too, not sure why

unfortunately the decklink api docs are poor and support is basically non existent so it's a bit tricky to work with

[claw]

I have found it flaky in that regard too, not sure why

unfortunately the decklink api docs are poor and support is basically non existent so it's a bit tricky to work with

This looks better. Log and screenshot:

[mattkhan]

interesting that it reports HDR10, never seen that before

@Hendrik what triggers JRVR to show that?

[mattkhan]

your log is dotted with lines like this

Code: [Select]

19:31:39.674156592 [7632] bmcapture.cpp:779            LOG_WARNING   filter       [BlackmagicCaptureFilter] Video capture discontinuity detected, 1 frames missed at frame 292

I suspect it explains the motion problem, it's a function of the need to convert the format of every single frame received. I didn't expect to need to do this & for it to be so slow so I'm doing it in the wrong place atm. A subsequent release should fix this (but that is a bit more involved so will take some days to get done)

[claw]

your log is dotted with lines like this

Code: [Select]

19:31:39.674156592 [7632] bmcapture.cpp:779            LOG_WARNING   filter       [BlackmagicCaptureFilter] Video capture discontinuity detected, 1 frames missed at frame 292

I suspect it explains the motion problem, it's a function of the need to convert the format of every single frame received. I didn't expect to need to do this & for it to be so slow so I'm doing it in the wrong place atm. A subsequent release should fix this (but that is a bit more involved so will take some days to get done)

Yes, still have the motion issue.    Also maybe related is that I have to set 450 ms audio delay in my AVR.     Audio is split out by HDfury VRROOM before sending to capture card.

Good progress, though.

[mattkhan]

Yes, still have the motion issue.    Also maybe related is that I have to set 450 ms audio delay in my AVR.     Audio is split out by HDfury VRROOM before sending to capture card.

fwiw, based on what I've seen, I'd expect a decklink card to be delayed somewhat relative to a magewell card in the same system for 2 reasons.... 1) the magewell sdk provides a low latency mode which means it should take less time to capture a frame, 2) decklink supports a v limited set of formats which require conversion (done on the cpu) before handing them to the renderer

overall i would think it means higher cpu usage & need to handle a somewhat larger delay vs a magewell card (but they're generally a fair bit cheaper so....)

[claw]

fwiw, based on what I've seen, I'd expect a decklink card to be delayed somewhat relative to a magewell card in the same system for 2 reasons.... 1) the magewell sdk provides a low latency mode which means it should take less time to capture a frame, 2) decklink supports a v limited set of formats which require conversion (done on the cpu) before handing them to the renderer

overall i would think it means higher cpu usage & need to handle a somewhat larger delay vs a magewell card (but they're generally a fair bit cheaper so....)

I am using a less powerful PC for the DeckLink installation.   An i5 instead of i7, and an RTX2080Ti instead of a 3080Ti.

[Hendrik]

interesting that it reports HDR10, never seen that before

@Hendrik what triggers JRVR to show that?

Its just the PQ transfer.

[claw]

I don't use the Presentation queue.   But if I enable it, the output video locks up.