https://www.bhphotovideo.com/explora/4k/4k-video-signal-guide
Quad-Link HD-SDI
Quad-Link HD-SDI transmits 4K as four separate 2K or 1080p signals. HD-SDI is a SMPTE standardized signal for 2K and 1080p video distribution. This makes Quad-Link HD-SDI a reliable, though cumbersome, way to distribute 4K video. You will need four separate 75 ohm BNC coax cables that support at least 1.5 Gb/s of bandwidth for Quad-Link HD-SDI. Quad-Link HD-SDI supports both DCI 4K and UHD 4K. The maximum quality supported by Quad-Link HD-SDI is 10-bit 4:2:2 at 30p. HD-SDI is a proven and extremely reliable signal for HD video, which is probably why Quad-Link HD-SDI is the most common way of distributing 4K on professional broadcast equipment.
Quad-Link HD-SDI以四個獨立2K或是1080p的訊號傳輸4K。HD-SDI是SMPTE標準2K與1080p影像訊號的傳輸方式,因此Quad-Link HD-SDI是可靠的,卻稍微無法扛起散播4K影像的任務。你依舊需要四條獨立的75歐姆的BNC同軸電纜,每條可在Quad-Link SDI支援至少1.5Gb/s頻寬。Quad-Link HD-SDI可支援DCI 4K與UHD 4K。Quad-Link HD-SDI最高支援到10 bit 4:2:2 30p。HD-SDI已經過認證,傳輸HD影像訊號非常穩定,這也許是為什麼Quad-Link HD-SDI在專業廣播設備裡,是最普遍傳播4K的方式
Quad-Link HD-SDI can be converted to the following signals:
Quad-Link HD-SDI可被轉換為以下訊號:
採用Blackmagic Mini Converter SDI to HDMI或AJA Hi5-4K 轉成HDMI 1.4
採用Blackmaigc Multiplex 4K轉成Dual-Link 3G-SDI
採用Blackmaigc Multiplex 4K轉成6G-SDI
• HDMI 1.4 with either the Blackmagic Miniconverter SDI to HDMI 4K or the AJA Hi5-4K
• Dual-Link 3G-SDI with the Blackmagic Multiplex 4K
• 6G-SDI with the Blackmagic Multiplex 4K
Quad-Link 3G-SDI
Quad-Link 3G-SDI is very similar to Quad-Link HD-SDI but, as the name implies, uses four 3G-SDI signals instead of HD-SDI. The extra bandwidth of 3G-SDI allows Quad-Link 3G-SDI to transmit 10-bit 4:2:2 4K at double the frame rate (up to 60p) or to transmit up to 12-bit 4:4:4 at the same frame rate (up to 30p). You will need four separate 75 ohm BNC coax cables that support at least 3 Gb/s of bandwidth for Quad-Link 3G-SDI. Quad-Link 3G-SDI is the most useful for post production where the extra color information in a 4:4:4 signal can be utilized. Currently no 4K cameras output a 4:4:4 signal, but some capture cards do. Because Quad-Link 3G-SDI exceeds the bandwidth of all other 4K signals currently on the market there are no ways to convert a Quad-Link 3G-SDI signal into anything else. However any device capable of Quad-Link 3G-SDI should also do Quad-Link HD-SDI.