Has anybody been able to stream with a 4K camera with low latency?

I’m wondering if it’s possible (using any tool available in the market). Or there’s just the option to stream in 1080p while recording in 4K

Hi @Gabriel1,

Latency depends on the camera, any encoding, the decoding and display device, and any passthrough hardware in between. To minimise latency it’s best to minimise everything between the camera’s pixel capturing and the monitor’s pixel displaying, but there are often required trade-offs in between that limit how low the latency can be.

In an ideal scenario you would be able to have an ethernet-based camera that passes raw pixels directly through the tether and up to the display device. Working against that,

  • a pure ethernet-based tether generally cannot maintain high bandwidths over significant distances
  • there’s generally data other than the video footage that needs to travel via the same tether (e.g. vehicle telemetry and controls)
    • some form of network switch is required for multiple connections to go through the same cable, or additional tether wires and a separate tether interface just for video (which may suffer from interference)
  • 4K footage at any appreciable frame-rate is a lot of data
    • it’s common to require some form of encoding to compress that data before sending it
      • ideally the relevant encoding is performed on the camera, both to reduce latency and so that you don’t need extra hardware between the camera and tether interface
      • in order for it to fit within the tether bandwidth the amount of compression may need to be significant, which is time-consuming to encode and/or requires throwing away significant amounts of data (lossy encoding)
      • an encoded signal requires decoding on the other end, which adds some latency
        • a high-end computer can help to minimise the decoding latency, but can be expensive
    • it can also/alternatively help to have a high bandwidth tether (e.g. fiber optic)

There are two main ways this could be done:

  • the camera may support onboard recording while providing a lower resolution preview stream
  • you could add some hefty hardware to the pipeline which accepts and records the 4K stream from the camera, while also downsampling (and likely encoding) it to a lower resolution which then gets streamed to the topside