Machine configuration for n=2 Blackmagic HDMi Video Capture card

[Dev Singhvi]

HI,

Can some one help me with what kind of machine configuration is required for installing n=2 Blackmagic HDMi Video Capture card in the same machine via STB Tester?

Also, what is the best HDMI stripper that can be used with black magic video capture card?

Thanks

[alexey....@gmail.com]

AFAIK you simply install the second card and modify the "device-number" parameter in the source_pipeline entry of your stbt config files (see https://github.com/stb-tester/stb-tester/wiki/Getting-started-with-stb-tester and https://github.com/stb-tester/stb-tester/wiki/Video-capture-hardware-for-DIY-stb-tester-rigs). Then you 2 stbt config files for each of the cards, e.g.:

stbt_card0_720p.conf:
source_pipeline = decklinksrc connection=HDMI mode=720p50 device-number=0

stbt_card1_1080p.conf:
source_pipeline = decklinksrc connection=HDMI mode=1080p50 device-number=1

Now run the tests using one of your config files:
STBT_CONFIG_FILE=~/.config/stbt/stbt_card0_720p.conf stbt run mytest.py

Note: stb-tester devs reported stability issues with multiple decklink card setups!

As for the HDCP stripper, I use this one: https://www.amazon.de/HDMI-Splitter-Verteiler-Full-HD-1080P/dp/B00BY07MZG - it's fairly reliable, but the HDMI slots can get a little loose over time. I bent the slot casing a little inward to keep the plugs snug. It's also advisable to use HDMI cables labeled as "high speed" to avoid artifacts and signal loss.

[Dev]

thank you, can also tell what kind h/w machine i should buy two support 2 black magic cards.

[ramires...@gmail.com]

I'd say any decent x64 hardware will do, as long as you can reliably run Ubuntu 14/16 on it. I'm working with an i7-3770 on a Gigabyte GA-Z77X-D3H motherboard, 8GB RAM and a Samsung EVO SSD. Ubuntu runs flawlessly out-of-the-box and the machine has more than enough power to handle 1080p grabbing and whatnot. I'm pretty sure it can also handle 2 Intensity Pro 4K cards simultaneously, but haven't actually tried it as I'm not convinced by the buggy decklink drivers - just look at the GStreamer forums to get the idea.