Magewell USB Capture SDI Plus

About this product

In a working SDI system the camera feed is already going somewhere: a monitor, a vision mixer, a recorder. The USB Capture SDI Plus lets you add a computer for streaming or recording without taking that feed away. It takes one SDI signal and passes it to a computer over USB, so streaming, recording or conferencing software can use it as a video source. SDI is the locking coaxial video connection used on professional cameras and vision mixers. Compared with a basic SDI to USB capture device, this model adds an SDI loop-through, a line-level audio input and an audio output.

What goes in

• SDI. One BNC input for SD, HD or 3G-SDI, taking up to 2048×1080 at 60 frames per second, 4:2:2 10-bit. That covers 1080p60. For 4K over SDI, see the 4K Plus model below.
• Cable length. Up to 150 m for 3G-SDI signals, so the capture computer can be a long way from the camera.
• SDI audio. The input accepts up to eight embedded channels.
• Line input. A 3.5 mm line-in socket takes analogue audio, for example from a sound desk, which saves adding a separate audio interface to the computer.

What comes out

• Loop-through. One BNC output that passes the SDI source on to the next device, such as a monitor or a mixer, up to the same maximum as the input.
• To the computer. Uncompressed video over USB in YUY2, UYVY, RGB24 or RGB32 format, up to 2048×1080, with frame rates up to 120 fps. The input takes up to 60 fps, and the device converts that when your software asks for a higher rate, up to 120 fps.
• Audio to the computer. Up to two channels at 48 kHz.
• Audio output. A 3.5 mm output plays the sound taken from the SDI signal, so you can listen to what the camera is sending.

Where it earns its place

The device can crop, scale up or down, de-interlace (turn an interlaced picture into full frames), change aspect ratio, convert colour format, convert frame rate, and flip or mirror the picture. This is FPGA-based processing with zero CPU usage. In plain terms, the conversion work is done inside the device, which frees your computer for the software you are running. Scaling makes the picture fit the size you ask for, using the detail in the source.

• Keeping the chain intact. The camera feed carries on to the monitor or mixer through the loop-through while the computer captures it. You can add streaming to an existing installation by putting it in line.
• Sound from a desk. The line input brings a separate analogue feed into the capture alongside the picture, which suits venues where the sound is mixed separately from the cameras.
• Power. It runs from the USB port with no additional power source, drawing about 2.5 W at most (0.5 A at 5 V), so there is one cable to the computer and nothing to plug into the wall.
• Size. 110.7 × 56.8 × 17 mm, compact enough for a crowded production desk. A 63 cm USB 3.0 cable is in the box.

Setting it up

• Driver-free. The USB Capture family installs without a driver and detects the input automatically. Connect the source, plug the USB cable into the computer, then pick the device in your software.
• USB port. The connection is USB 3.0. It is compatible with USB 2.0 and USB 3.1 Gen 1 as well.
• Operating systems. Windows 10 and 11 (and Windows Server 2016 to 2025), Linux with kernel 2.6.35 and above on x86, x64 and ARM, Mac OS X 10.9 and above, macOS 10.12 and above, and Chrome OS.
• Software. It works with Zoom Rooms, Microsoft Teams, Skype for Business, Google Hangouts, GoToMeeting, VLC, OBS Studio, XSplit and QuickTime Player, plus other DirectShow, V4L2 or AVCaptureSession software, so you can use the software your team already runs.
• Settings and firmware. Magewell’s free USB Capture Utility shows and changes the capture settings and upgrades the firmware.

Where it sits in the range

The USB Capture SDI Gen 2 is the simpler SDI model, with a single SDI input and the USB connection. The USB Capture HDMI Plus is the HDMI counterpart. For 4K over SDI, look at the USB Capture SDI 4K Plus. The whole family is on the USB Capture range page.