Magewell's AV-over-IP and Live Streaming Solution Assists Hospital Surgical Demonstration

Surgical teaching no longer has to mean standing in the operating room. With Magewell Pro Convert NDI® encoders at the video sources and the hospital’s existing IP network in between, pictures from the surgical field camera, the room camera and the endoscope can be shown live in a separate classroom, and an Ultra Stream encoder can stream the finished programme to doctors elsewhere. This approach suits established operating rooms in particular. Many surgical demonstration systems are simple to install only when a new room is being built. In an existing room the concern is to add flexible, reliable video links without disturbing the infrastructure that is already there.

This article describes how two kinds of Magewell encoder work together to link the operating room (OR) and a separate classroom: Pro Convert NDI® encoders for AV over IP, such as the Pro Convert HDMI Plus and Pro Convert SDI Plus, and Ultra Stream live streaming encoders. A typical workflow is as follows:

In the operating room, one or more Pro Convert NDI encoders receive signals from medical equipment such as surgical field cameras, panoramic cameras and endoscopes. Each encoder converts its signal into an NDI High Bandwidth stream and sends it over the hospital LAN. Choose a model with a loop-through output, such as the Pro Convert HDMI Plus, SDI Plus or one of the 4K Plus models, and the original signal also passes straight on to the equipment it already feeds, for example the room’s existing Picture Archiving and Communication System (PACS). The Pro Convert HDMI TX and SDI TX have no loop-through, so they suit sources that feed nothing else.

In the demonstration classroom, a surgical demonstration host system receives the NDI streams from the operating room and applies production effects such as picture-in-picture, cropping and zooming in its own software. Some demonstration systems are NDI compatible and can decode the streams directly. For others, a Magewell Pro Convert NDI decoder such as the Pro Convert NDI to HDMI or Pro Convert NDI to SDI turns each stream back into an HDMI or SDI signal for the host’s inputs.

The finished programme is output to a projector or display, where physicians and students watch. The host can also send a signal to the Ultra Stream encoder, which streams it to a server or platform for doctors who are not in the classroom.

Pro Convert NDI encoders bring ordinary HDMI or SDI signals into an NDI workflow, so existing cameras and medical equipment stay in use. Several units can send several signals as NDI over the hospital IP network, which avoids running a dedicated video cable for each source. The encoders take their power from the network switch over PoE (IEEE 802.3af) or from the supplied USB power adaptor, so a single network cable can be the only new cable at each source. NDI is designed for live production, which is what makes real-time interaction between the operating room and the classroom practical.

The guiding physicians and students in the classroom are often most interested in the endoscope picture. A Pro Convert NDI decoder can take the endoscope stream straight from the LAN and feed it to the projector or display. That relieves the demonstration host of decoding and outputting several signals at once, leaving more of its capacity for encoding, production and recording, which matters most with 4K endoscopes. The Pro Convert NDI to HDMI 4K decodes one stream at up to 4K at 60 frames per second. Where the operating room and classroom are on different network segments, an NDI Discovery Server lets the NDI devices find each other.

The Ultra Stream encoder sends the live surgery video to the hospital’s own streaming system or to an external platform over RTMP, RTMPS or RTSP. Staff can control it with the buttons on the unit, a browser-based interface or a smartphone app, so starting a stream does not need a specialist. It connects by wired Ethernet or Wi-Fi, and supports a 3G/4G USB modem (not included) where no network is available.

Many medical equipment manufacturers now offer 4K endoscopes and panoramic cameras. Pro Convert NDI encoders and decoders include models for 4K at 60 frames per second: the Pro Convert HDMI 4K Plus and Pro Convert 12G SDI 4K Plus encode it, and the Pro Convert NDI to HDMI 4K decodes it. The Ultra Stream HDMI accepts HDMI signals up to 4K at 60 frames per second (4:2:0) and streams at up to 1080p60. Because each source has its own small encoder, rooms can be added or upgraded one at a time. The devices also provide HTTP APIs, and can be managed from their web interface or Magewell Control Hub, so systems integrators and hospital IT and AV teams can bring them into their own management systems.