Capture Card Acronyms: What They Mean and Why They Matter

Capture cards come with a long list of acronyms on the box. A few of them directly determine whether your setup works the way you expect, and others are less critical than they look. Here’s what each one means and when it matters.

These terms cover how a signal physically gets from your source into your computer. Get this layer wrong and nothing downstream matters: you won’t have a picture to capture at all.

The cable running from your console, camera, or PC's GPU into your capture card. Versions matter more than people think. HDMI 2.0 tops out around 4K60, while HDMI 2.1 unlocks higher refresh rates and resolutions like 4K120. Normally your source reads the capture card's EDID (covered below) and automatically steps down to a resolution and refresh rate the card supports, so a 4K120 source on an HDMI 2.0 card would drop to 4K60 rather than losing the signal outright. Elgato Game Capture 4K X uses HDMI 2.1, while Elgato Game Capture 4K S uses HDMI 2.0, which is a concrete example of why checking the version before you buy matters.

How the capture card talks to your computer. This is usually the actual bottleneck in a capture setup, not the HDMI side. A card capturing 4K60 needs real USB 3.0 (5 Gbps) or better bandwidth to move that much uncompressed or lightly compressed video without dropping frames.

UVC is a standard that lets a capture device show up as a generic webcam to any application, with no drivers required. A UVC-compliant capture card works instantly in OBS, Zoom, Discord, or Teams. Without it, you’re stuck installing proprietary software just to get a picture. Elgato capture cards are UVC-compliant, which is why they work right away in most streaming and video call apps without extra setup. The audio equivalent is UAC (USB Audio Class), which does the same job for plug-and-play audio recognized natively by the OS.

Internal capture cards like 4K Pro, as opposed to external USB ones, connect via PCIe slots on your motherboard. PCIe capture generally offers lower latency and higher throughput than USB, at the cost of needing to physically open your PC.

Once a signal is connected, these terms describe what happens to the picture itself: how much of the source’s detail, color, and motion smoothness survives the trip through your capture card.

A small block of data your capture card sends back to the source device, describing what resolutions and refresh rates it can accept. Elgato capture cards handle EDID merging automatically, so this is one of the things you generally don't have to think about once your setup is running.

Wider brightness and color range in the source signal. There are a few different HDR formats in use, but HDR10 is the one you'll run into most on consoles and PCs. Capturing HDR content properly, rather than just passing it through, requires hardware that can tone-map or preserve that extra data. It's a spec worth checking if you're capturing modern console games. Elgato capture cards support HDR10 passthrough and capture, and this guide on recording HDR walks through how that works in Elgato Studio.

VRR lets a display's refresh rate sync dynamically with the source's frame rate, reducing screen tearing. Capture cards that support VRR passthrough keep that sync intact, so the monitor you're playing on stays smooth while you record or stream. A related handshake, ALLM (Auto Low Latency Mode), automatically switches a display to a low-latency picture mode, which mainly matters for passthrough on gaming setups.

Describes how much color detail is kept relative to brightness detail in a compressed video signal. 4:4:4 keeps full color fidelity and works best for text-heavy or graphics-heavy capture. 4:2:0 saves bandwidth but can soften fine color detail. It's worth knowing if your footage looks slightly muddy despite a sharp source. For a deeper visual breakdown of how each format compares, RTINGS has a good explainer.

Two different ways of encoding color in a video signal. YUV separates brightness from color information, which is efficient for compression. RGB encodes each pixel’s red, green, and blue values directly, which is better for graphics and text fidelity but more bandwidth-intensive.

Raw video is enormous, so capture hardware and software compress it before it hits your drive or your stream. These acronyms describe the tradeoffs each compression choice makes between file size, quality, and processing overhead.

A modern video compression codec that keeps file sizes smaller than its predecessor at similar quality. This is useful for high-resolution capture, where storage and bandwidth add up fast. Elgato Studio lets you choose your recording format, and this guide breaks down when to use HEVC versus other options.

The newest widely adopted codec, and generally the most efficient of the bunch: AV1 can match HEVC's quality at a lower bitrate, or better quality at the same bitrate. It's open and royalty-free, which is part of why platforms like YouTube and Twitch have been pushing adoption. The catch is hardware support: AV1 encoding needs a newer GPU or dedicated encoder chip, so it's not universal yet the way H.264 is.

The older, more universally compatible codec. Slightly less efficient than HEVC but still a safe default for broad software compatibility.

Each frame is compressed individually as a JPEG image rather than using inter-frame compression. This means lower latency but larger file sizes, which is common in cheaper capture hardware or as a fallback format.

This is the last leg of the journey: getting your captured video out to viewers, other machines, or other rooms. It’s where capture stops being about recording and starts being about delivery.

The protocol most streaming software uses to send your capture out to platforms like Twitch or YouTube.

NDI allows video sources to be sent and received over a local network rather than via a direct cable connection. This is handy for multi-camera or multi-room production setups where running HDMI cables everywhere isn’t practical.

A broadcast-standard connection type used in professional video equipment, valued for its ability to run over long cable distances without signal loss. It’s less common in creator setups and more standard in broadcast trucks and studios.

None of these acronyms exists to make a spec sheet look impressive. Each one answers a real question. Will my source signal be recognized? That's EDID. Will my software see the device without drivers? That's UVC. Will my footage keep its color fidelity? That's chroma subsampling and RGB/YUV. Will my file sizes be manageable? That's your codec choice. Understanding the acronym means understanding what you're actually troubleshooting when something doesn't work, which in this hobby is eventually all of us.

If you're choosing a capture card and want to see how these specs translate to real products, our capture card comparison guide breaks down the lineup by use case.