Decklink Quad 2 1080p59.94 Color Space (pixel format) and Sync


#1

Hello. I’m changing over some workflows from 1080i59.94 to 1080p59.94 and get a warning on the Quad 2 that 1080p59.94 is not supported on the device when it is. It seems that the test to determine compatibility is based on 8 bit RGB, but past 1080p30, the Quad 2 is only 8 or 10-bit YUV 4:2:2.

The output seems fine, but I’m wondering if there is any sacrifices or performance hits behind the scenes.

Also, when using the decklink producer at 1080p, it throws a lot of out-sync warnings. The out-sync messages don’t appear if playing a 1080p file or html page. Any insights are appreciated!


#2

IIRC Decklinks only support alpha in 8-bit BGRA and that’s the reason for using that format. Is your alpha output correct?

(On a sidenote, I guess that’s a limitation for the internal keyers. Perhaps we should be able to support 10-bit YUV when we do separate key outputs.)


#3

I have all 8 channels set as individual channels - with none as keys. In the config, to help test, I’ve tried it with just 1 channel and with multiple. I don’t think there’s a way to use the config to turn off the keyer, instead I settle for the “failed to enable external keyer” error.


#4

I guess CCG sends 8bitBGRA to the card and it transforms it to 10bitYUV, and that could be delaying frames and giving you those out-sync messages. Please post a log of one run with CCG.


#5

Set the keyer to default instead of external to get rid of that error.


#6

Sorry for the delay in posting this (and Happy New Year!) - using the latest build with a pretty simple config to help eliminate possible issues. Playing back a 1080p59.94 clip that was recorded on a BMD Video Assist via Decklink 1 earlier.

Also, @didikunz - I tired keyer = default, but pretty sure that is the same as setting it to external (in the decklink consumer code)

2020-01-01 14:34:42.039] [info]    ############################################################################
[2020-01-01 14:34:42.040] [info]    CasparCG Server is distributed by the Swedish Broadcasting Corporation (SVT)
[2020-01-01 14:34:42.040] [info]    under the GNU General Public License GPLv3 or higher.
[2020-01-01 14:34:42.040] [info]    Please see LICENSE.TXT for details.
[2020-01-01 14:34:42.040] [info]    http://www.casparcg.com/
[2020-01-01 14:34:42.040] [info]    ############################################################################
[2020-01-01 14:34:42.040] [info]    Starting CasparCG Video and Graphics Playout Server 2.3.0 7829b13b Dev
[2020-01-01 14:34:42.607] [info]    Initializing OpenGL Device.
[2020-01-01 14:34:42.608] [info]    Initialized OpenGL 4.5.0 NVIDIA 431.70 NVIDIA Corporation
[2020-01-01 14:34:42.670] [info]    D3D11: Selected adapter: NVIDIA Quadro M1000M
[2020-01-01 14:34:42.670] [info]    D3D11: Selected feature level: 45056
[2020-01-01 14:34:42.679] [info]    Initialized ffmpeg module.
[2020-01-01 14:34:42.680] [info]    Initialized oal module.
[2020-01-01 14:34:42.680] [info]    Initialized decklink module.
[2020-01-01 14:34:42.680] [info]    Initialized screen module.
[2020-01-01 14:34:42.680] [info]    Initialized newtek module.
[2020-01-01 14:34:42.773] [info]    Initialized html module.
[2020-01-01 14:34:42.927] [info]    Initialized flash module.
[2020-01-01 14:34:42.929] [info]    Initialized bluefish module.
[2020-01-01 14:34:42.929] [info]    Initialized image module.
[2020-01-01 14:34:42.929] [info]    "C:/casparcg-server-windows\casparcg.config":
[2020-01-01 14:34:42.929] [info]    -----------------------------------------
[2020-01-01 14:34:42.929] [info]    <?xml version="1.0" encoding="utf-8"?>
[2020-01-01 14:34:42.929] [info]    <configuration>
[2020-01-01 14:34:42.929] [info]       <paths>
[2020-01-01 14:34:42.929] [info]          <media-path>media/</media-path>
[2020-01-01 14:34:42.929] [info]          <log-path>log/</log-path>
[2020-01-01 14:34:42.929] [info]          <data-path>data/</data-path>
[2020-01-01 14:34:42.929] [info]          <template-path>template/</template-path>
[2020-01-01 14:34:42.929] [info]       </paths>
[2020-01-01 14:34:42.929] [info]       <lock-clear-phrase>secret</lock-clear-phrase>
[2020-01-01 14:34:42.929] [info]       <channels>
[2020-01-01 14:34:42.929] [info]          <channel>
[2020-01-01 14:34:42.929] [info]             <video-mode>1080p5994</video-mode>
[2020-01-01 14:34:42.929] [info]             <consumers>
[2020-01-01 14:34:42.929] [info]                <decklink>
[2020-01-01 14:34:42.929] [info]                   <device>1</device>
[2020-01-01 14:34:42.929] [info]                   <embedded-audio>false</embedded-audio>
[2020-01-01 14:34:42.929] [info]                   <latency>normal</latency>
[2020-01-01 14:34:42.929] [info]                   <keyer>default</keyer>
[2020-01-01 14:34:42.929] [info]                   <buffer-depth>3</buffer-depth>
[2020-01-01 14:34:42.929] [info]                </decklink>
[2020-01-01 14:34:42.929] [info]             </consumers>
[2020-01-01 14:34:42.929] [info]          </channel>
[2020-01-01 14:34:42.929] [info]       </channels>
[2020-01-01 14:34:42.929] [info]       <controllers>
[2020-01-01 14:34:42.929] [info]          <tcp>
[2020-01-01 14:34:42.929] [info]             <port>5250</port>
[2020-01-01 14:34:42.929] [info]             <protocol>AMCP</protocol>
[2020-01-01 14:34:42.929] [info]          </tcp>
[2020-01-01 14:34:42.929] [info]       </controllers>
[2020-01-01 14:34:42.929] [info]       <amcp>
[2020-01-01 14:34:42.929] [info]          <media-server>
[2020-01-01 14:34:42.929] [info]             <host>localhost</host>
[2020-01-01 14:34:42.929] [info]             <port>8000</port>
[2020-01-01 14:34:42.929] [info]          </media-server>
[2020-01-01 14:34:42.929] [info]       </amcp>
[2020-01-01 14:34:42.929] [info]    </configuration>
[2020-01-01 14:34:42.929] [info]    -----------------------------------------
[2020-01-01 14:34:42.938] [info]    Initialized OpenGL Accelerated GPU Image Mixer for channel 1
[2020-01-01 14:34:42.939] [info]    video_channel[1|1080p5994] Successfully Initialized.
[2020-01-01 14:34:42.969] [warning] Device does not support video-format: 1080p59.94
[2020-01-01 14:34:42.970] [info]    DeckLink Quad 2 [1-1|1080p5994] Disabled low-latency mode.
[2020-01-01 14:34:42.971] [error]   DeckLink Quad 2 [1-1|1080p5994] Failed to enable external keyer.
[2020-01-01 14:34:42.998] [info]    DeckLink Quad 2 [1-1|1080p5994] Initialized.
[2020-01-01 14:34:42.998] [info]    Initialized channels.
[2020-01-01 14:34:43.008] [info]    Initialized controllers.
[2020-01-01 14:34:43.009] [info]    Initialized osc.
[2020-01-01 14:34:43.022] [info]    DeckLink Quad 2 [1-1|1080p5994] Reference signal: not detected.
[2020-01-01 14:34:43.316] [info]    async_event_server[:5250] Accepted connection from 127.0.0.1 (1 connections).
[2020-01-01 14:34:43.316] [info]    Received message from 127.0.0.1: VERSION SERVER\r\n
[2020-01-01 14:34:43.316] [info]    async_event_server[:5250] Accepted connection from 127.0.0.1 (2 connections).
[2020-01-01 14:34:43.316] [info]    Sent message to 127.0.0.1:201 VERSION OK\r\n2.3.0 7829b13b Dev\r\n
[2020-01-01 14:34:43.317] [info]    Received message from 127.0.0.1: VERSION SERVER\r\n
[2020-01-01 14:34:43.317] [info]    Sent message to 127.0.0.1:201 VERSION OK\r\n2.3.0 7829b13b Dev\r\n
[2020-01-01 14:34:43.327] [info]    Received message from 127.0.0.1: INFO\r\n
[2020-01-01 14:34:43.327] [info]    Received message from 127.0.0.1: INFO\r\n
[2020-01-01 14:34:43.327] [info]    Sent message to 127.0.0.1:200 INFO OK\r\n1 1080p5994 PLAYING\r\n\r\n
[2020-01-01 14:34:43.327] [info]    Sent message to 127.0.0.1:200 INFO OK\r\n1 1080p5994 PLAYING\r\n\r\n
[2020-01-01 14:34:43.334] [info]    Received message from 127.0.0.1: CLS\r\n
[2020-01-01 14:34:43.334] [info]    Received message from 127.0.0.1: CLS\r\n
[2020-01-01 14:34:43.347] [info]    Received message from 127.0.0.1: TLS\r\n
[2020-01-01 14:34:43.347] [info]    Received message from 127.0.0.1: TLS\r\n
[2020-01-01 14:34:43.361] [info]    Received message from 127.0.0.1: DATA LIST\r\n
[2020-01-01 14:34:43.361] [info]    Received message from 127.0.0.1: DATA LIST\r\n
[2020-01-01 14:34:43.365] [info]    Sent message to 127.0.0.1:200 CLS OK\r\n"8421"  STILL  777030 20200101142711 NaN 0/0\r\n\r\n
[2020-01-01 14:34:43.371] [info]    Received message from 127.0.0.1: THUMBNAIL LIST\r\n
[2020-01-01 14:34:43.371] [info]    Received message from 127.0.0.1: THUMBNAIL LIST\r\n
[2020-01-01 14:34:43.385] [info]    Sent message to 127.0.0.1:200 CLS OK\r\n"8421"  STILL  777030 20200101142711 NaN 0/0\r\n\r\n
[2020-01-01 14:34:43.397] [info]    Sent message to 127.0.0.1:200 TLS OK\r\n\r\n
[2020-01-01 14:34:43.423] [info]    Sent message to 127.0.0.1:200 TLS OK\r\n\r\n
[2020-01-01 14:34:43.424] [info]    Sent message to 127.0.0.1:200 DATA LIST OK\r\n\r\n
[2020-01-01 14:34:43.424] [info]    Sent message to 127.0.0.1:200 DATA LIST OK\r\n\r\n
[2020-01-01 14:34:43.439] [info]    Sent message to 127.0.0.1:200 THUMBNAIL LIST OK\r\n"8421" 20200101T142711 78205\r\n\r\n
[2020-01-01 14:34:43.456] [info]    Sent message to 127.0.0.1:200 THUMBNAIL LIST OK\r\n"8421" 20200101T142711 78205\r\n\r\n
[2020-01-01 14:35:14.528] [info]    Received message from Console: play 1 decklink 2\r\n
[2020-01-01 14:35:14.579] [info]    DeckLink Quad 2 [2|1080p5994] Initialized
[2020-01-01 14:35:14.667] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -16.6875
[2020-01-01 14:35:14.682] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -33.375
[2020-01-01 14:35:14.728] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -50.0625
[2020-01-01 14:35:14.775] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -66.7292
[2020-01-01 14:35:14.810] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -83.4167
[2020-01-01 14:35:14.847] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -100.104
[2020-01-01 14:35:14.861] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -116.792
[2020-01-01 14:35:14.874] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -133.479
[2020-01-01 14:35:14.891] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -150.146
[2020-01-01 14:35:14.903] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -166.833
[2020-01-01 14:35:14.919] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -183.521
[2020-01-01 14:35:14.938] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -200.208
[2020-01-01 14:35:14.951] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -216.896
[2020-01-01 14:35:14.967] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -233.562
[2020-01-01 14:35:14.982] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -250.25
[2020-01-01 14:35:14.996] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -266.938
[2020-01-01 14:35:15.011] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -283.625
[2020-01-01 14:35:15.025] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -300.313
[2020-01-01 14:35:15.036] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -316.979
[2020-01-01 14:35:15.052] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -333.667
[2020-01-01 14:35:15.071] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -350.354
[2020-01-01 14:35:15.088] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -367.042
[2020-01-01 14:35:15.103] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -383.729
[2020-01-01 14:35:15.119] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -400.396
[2020-01-01 14:35:15.144] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -417.083
[2020-01-01 14:35:15.157] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -433.771
[2020-01-01 14:35:15.168] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -450.458
[2020-01-01 14:35:15.185] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -467.146
[2020-01-01 14:35:15.199] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -483.812
[2020-01-01 14:35:15.215] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -500.5
[2020-01-01 14:35:15.231] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -517.188
[2020-01-01 14:35:15.246] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -533.875
[2020-01-01 14:35:15.261] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -550.563
[2020-01-01 14:35:15.276] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -567.229
[2020-01-01 14:35:15.293] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -583.917
[2020-01-01 14:35:15.304] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -600.604
[2020-01-01 14:35:15.320] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -617.292
[2020-01-01 14:35:15.334] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -633.979
[2020-01-01 14:35:15.346] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -650.646
[2020-01-01 14:35:15.362] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -667.333
[2020-01-01 14:35:15.379] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -684.021
[2020-01-01 14:35:15.393] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -700.708
[2020-01-01 14:35:15.405] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -717.396
[2020-01-01 14:35:15.421] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -734.062
[2020-01-01 14:35:15.435] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -750.75
[2020-01-01 14:35:15.452] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -767.438
[2020-01-01 14:35:15.469] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -784.125
[2020-01-01 14:35:15.484] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -800.813
[2020-01-01 14:35:15.497] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -817.479
[2020-01-01 14:35:15.515] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -834.167
[2020-01-01 14:35:15.532] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -850.854
[2020-01-01 14:35:15.548] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -867.542
[2020-01-01 14:35:15.564] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -884.229
[2020-01-01 14:35:15.579] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -900.896
[2020-01-01 14:35:15.595] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -917.583
[2020-01-01 14:35:15.610] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -934.271
[2020-01-01 14:35:15.622] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -950.958
[2020-01-01 14:35:15.638] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -967.646
[2020-01-01 14:35:15.654] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -984.312
[2020-01-01 14:35:15.668] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1001
[2020-01-01 14:35:15.696] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1017.69
[2020-01-01 14:35:15.708] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1034.38
[2020-01-01 14:35:15.720] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1051.06
[2020-01-01 14:35:15.737] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1067.73
[2020-01-01 14:35:15.751] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1084.42
[2020-01-01 14:35:15.768] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1101.1
[2020-01-01 14:35:15.783] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1117.79
[2020-01-01 14:35:15.799] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1134.48
[2020-01-01 14:35:15.816] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1151.15
[2020-01-01 14:35:15.832] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1167.83
[2020-01-01 14:35:15.847] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1184.52
[2020-01-01 14:35:15.863] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1201.21
[2020-01-01 14:35:15.878] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1217.9
[2020-01-01 14:35:15.891] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1234.56
[2020-01-01 14:35:15.903] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1251.25
[2020-01-01 14:35:15.918] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1267.94
[2020-01-01 14:35:15.933] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1284.63
[2020-01-01 14:35:15.949] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1301.31
[2020-01-01 14:35:15.965] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1317.98
[2020-01-01 14:35:15.981] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1334.67
[2020-01-01 14:35:15.998] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1351.35
[2020-01-01 14:35:16.015] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1368.04
[2020-01-01 14:35:16.032] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1384.73
[2020-01-01 14:35:16.049] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1401.4
[2020-01-01 14:35:16.066] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1418.08
[2020-01-01 14:35:16.082] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1434.77
[2020-01-01 14:35:16.099] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1451.46
[2020-01-01 14:35:16.115] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1468.15
[2020-01-01 14:35:16.132] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1484.81
[2020-01-01 14:35:16.149] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1501.5
[2020-01-01 14:35:16.166] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1518.19
[2020-01-01 14:35:16.182] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1534.88
[2020-01-01 14:35:16.199] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1551.56
[2020-01-01 14:35:16.216] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1568.23
[2020-01-01 14:35:16.232] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1584.92
[2020-01-01 14:35:16.248] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1601.6
[2020-01-01 14:35:16.266] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1618.29
[2020-01-01 14:35:16.282] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1634.98
[2020-01-01 14:35:16.303] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1651.65
[2020-01-01 14:35:16.318] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1668.33
[2020-01-01 14:35:16.334] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1685.02
[2020-01-01 14:35:16.350] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1701.71
[2020-01-01 14:35:16.366] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1718.4
[2020-01-01 14:35:16.382] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1735.06
[2020-01-01 14:35:16.399] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1751.75
[2020-01-01 14:35:16.416] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1768.44
[2020-01-01 14:35:16.434] [warning] DeckLink Quad 2 [2|1080p5994] out-sync changed: -1785.13

#7

Try with the command: PLAY 1-1 DECKLINK DEVICE 1 FORMAT 1080p5994 That usually works for me.


#8

Same result with that too :frowning:


#9

I notice that you have a mobile GPU, so are you perhaps using an extension chassis? 1080P is twice the bandwidth of 1080I, could this be a bandwidth issue?


#10

Yes, the only format with alpha supported by the decklink is 8bit RGBA. So caspar always sends that off.
I believe it is the driver doing the conversion rather than the cards themselves, so I expect some cpu cost and potential timings variances there.

While I would like to be able to send YCbCr to the decklinks where possible, that doesnt fit into the existing mixed frame flow at all.