Video capture features allow Delta Media Servers to composite live feeds into the Delta Server output. This could be from another physical device such as a video camera, or over the network as a video share using Spout, or in the form of a live web page, or a broadcast stream. The following are some example use-cases.
➢Search keyword ‘capture’ in the Delta User Guide.
Hardware capture
The project requires a multiple server solution in a theme park for a stage show, and as visitors walk into the arena, their reactions are to be captured and composited within the main display. The Delta Media Server driving the display will have a capture card capable of taking two HDMI inputs from two separate video cameras. On screen there will be two overlaid images showing what the cameras can see.
Delta Media Server supports capture cards from the following manufacturers, that will accept inputs from various live or playback devices and sources:
•Datapath*
•Matrox
•Magewell
•Blackmagic
* Datapath DisplayPort Cards: Variable Resolution Capture
If the capture source connected to a Datapath DP capture card changes, Delta will interpret the incoming feed at an incorrect frame rate (for example when set up for a 3840 × 2160@60 fps source, a replacement source of 1920 × 1080@60 fps when forced to the same height and width, may be interpreted down to 15 fps).
This can be resolved by monitoring the capture feed resolution by editing a Delta System Sequence and enabling it with the System Sequences checkbox. Copy and paste this block:
Sequence name: OnSystem_CaptureSignalChanged
$startblock if($signalpresent == 1) { MEDIAPROPERTIES ctrlname=$system_resextctrlname forcew=$pixels forceh=$lines } $endblock |
Web capture
Stadium managers for a football game are using a Delta Media Server to drive a massive live coverage display using camera feeds to a capture card. They want to overlay results from a web page and the home team’s Twitter feed. The camera capture resource is in full-screen mode. By adding ‘Web Capture Resources’ to the Delta timeline, with URL addresses for the additional feeds, these can be re-sized/positioned to suit and switched in or out during the match.
Streaming service
A number of TV channels offer encrypted streaming services; a venue wants to be able to incorporate one using Zixi Broadcaster and Reciever. By using a Stream capture resource on the Delta timeline, the broadcast can be composited as a window in the playback display. All that is required is the Zixi licence and the relevant URL.
NDI (Network Device Interface)
A project for a live video games conference requires four PC gamers to be seen playing against each other, with each of their displays to be composited within a main background display from a Delta Media Server. By placing all sources on the same network as the server, this becomes a suitable application for Newtek NDI* tools to pull in a stream from each player desktop and composite them live within the main display. Just set up the correct ports and add NDI capture resources to the Delta timeline using the NDI stream names.
* The protocol created by Newtek that allows for capture over IP. Designed with broadcast quality in mind, it has low frame latency and is well-suited to switching between inputs.
Page edited [d/m/y]: 23/05/2023