The DeckLink 4K Extreme 12G is an 8-lane PCIe Gen2 digital cinema capture and playback card built around two multi-rate 12G-SDI inputs and outputs, accepting resolutions from SD up to DCI 4K (4096 x 2160) at 60 fps. It handles 10-bit YUV and 8-, 10- and 12-bit RGB colour, with up/down/cross conversion and 3D stereoscopic output at full-bandwidth 4:4:4:4 RGB. A mezzanine card design puts 4K HDMI input and output on a second daughter card, with connections for two optional optical fibre modules adding dual-link optical SDI input and output. The included breakout cable brings out AES/EBU balanced XLR and unbalanced RCA audio, analogue video I/O, a reference input and RS-422 deck control. Flexible format support covers compressed formats such as ProRes and DNxHD as well as 12-bit 4:4:4 uncompressed video, and the card runs on Mac, Windows and Linux systems.