What to check before you buy
The SDI standard. SD-SDI carries standard definition, HD-SDI carries 720p and 1080i, and 3G-SDI carries 1080p at 50 or 60 frames per second. All three cards here take all three, up to 3G-SDI. If your source is 4K, it will usually be on HDMI 2.0, DisplayPort or 12G-SDI; for HDMI and DisplayPort 4K60 see the XtremeDV-UHD2 and XtremeDV-DP2.
How many sources at once. Count every camera or feed you need live at the same time. One four-channel card uses one slot; four single-channel cards cost less but use four slots. The chooser above shows both.
The free slot in your PC. The XtremeLC-SDI is low-profile and needs a x4 slot, so it suits small-form-factor and 1U machines. The XtremeRGB-SDI2 is a full-height x4 card. The XtremeDV-SDI4 needs a full-height x8 slot (a x16 slot works too). See PCIe bandwidth and slots.
The operating system. The XtremeLC-SDI and XtremeDV-SDI4 run on Windows 10, Windows 11, Windows Server and Linux. The XtremeRGB-SDI2 runs on Windows 10 and earlier and on Linux, so for a new Windows 11 PC choose the XtremeDV-SDI4 or XtremeLC-SDI cards.
Your software. Check that your recording, streaming or vision software supports the card before you buy. See compatible software for the list.
Monitoring. If the SDI signal also has to reach a monitor or recorder, the XtremeRGB-SDI2 has a loop-through output on each input.
Where SDI capture is used
Broadcast and live-event streaming from SDI cameras and vision mixers; lecture capture and distance learning; medical and surgical imaging recorded alongside other modalities; machine vision with SDI cameras; and control rooms that show SDI feeds on a video wall. The XtremeLC-SDI and XtremeRGB-SDI2 also work in a VSN video wall controller alongside other Xtreme cards.
Questions
What is an SDI capture card?
An SDI capture card is a PCIe card that takes the SDI output of a camera, vision mixer or broadcast feed over BNC coax and brings it into a PC, so software such as OBS, vMix, Wirecast or your own application can record, stream or display it.
Which SDI formats do these cards capture?
SD-SDI, HD-SDI and 3G-SDI, up to 1080p at 60 frames per second. The XtremeLC-SDI and XtremeRGB-SDI2 also take 2K digital cinema formats. For 4K sources, use the HDMI 2.0 or DisplayPort capture cards instead.
How many SDI inputs can I capture in one PC?
One card gives one, two or four SDI channels. You can fit more than one card in the same PC, as long as it has enough free PCIe slots of the right size: the XtremeLC-SDI and XtremeRGB-SDI2 need a x4 slot, the XtremeDV-SDI4 a x8 or x16 slot.
Which card works in a small or 1U PC?
The XtremeLC-SDI is a low-profile card, so it fits small-form-factor and 1U machines. The two- and four-channel cards are full-height.
Does the card pass the SDI signal on to a monitor?
The XtremeRGB-SDI2 has a loop-through BNC on each input (and the XtremeAV-SDI on its SDI input), so the signal carries on to a monitor or recorder. With the XtremeLC-SDI and XtremeDV-SDI4, use an SDI distribution amplifier if you need a second copy of the signal.
Do you ship outside the UK?
Yes. UK orders are normally delivered within 2–3 working days, and we ship worldwide. Prices on this page include UK VAT.