Have you heard of NDI??

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This is a network protocol for video/audio over IP. I am researching implementing a live-streaming platform in a school and the latest thing is NDI -- Network Device Interface.

I am looking at THIS broadcast video switcher for this project:


Here are some former students of mine from several years ago using an old version of Newtek hardware. You can see how the video feed of the two student announcers is transformed for the broadcast output on the far right monitor...

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I am wondering how NDI compares to the ONVIF and RTSP world of surveillance cams, which are cheap and powerful, compared to NDI-specific cams which run easily at about $2k for what seems like pretty basic video hardware.... VERY curious if any of you have utilized this kind of hardware or know much about it.
 

brianegge

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Most onvif IP cameras use H.265 or H.264 video compression. This technology groups blocks of the screen together and compresses it, and also sends delta frames before or after key frames. This means if the video is static you use little bandwidth. The video compression is done on the camera, and if the video is displayed, the receiver must decompress it.

The result is latency of a frame of two, though end to end it can be a second or more. Most ipcams don’t allow high enough bitrate to prevents artifacts when motion occurs on a scene.

NDI is a proprietary protocol, not an open standard. This has significantly reduced the number of systems which can interoperate with it. For example, it was briefly included in the VLC media player, until license caused it to be removed.

NDI does light compression on a scan line by scan line basis. This lets it send broadcast quality over Ethernet, with bit rates 100Mb or higher. You can send a signal like 1080p59.94 over IP, which the sender will receive with a latency of 16 scan lines. Actual end to end delays tend to be about one frame. This is important in live video production. NDI is most closely a competitor to SDI.

An IP cam typically has a low power arm processor. To encode NDI you need either a very fast processor or an FPGA. Typically camera manufacturers pay a license fee for NDI which can be activated after purchase of the hardware.
 
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Wow--- so it is a completely different protocol and transmission standard that has nothing in common with compressed feeds using h.264/h.265. The short answer-- it is likely never going to play nice with standard IP surveillance cams....

B&H has these NDI cams....
 

brianegge

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It would be nice if ipcams could broadcast NDI. We’d add more cameras to our live stream if they didn’t cost $2,000 each. We could go from RTSP to hdmi but we’d still have the latency issue.
 
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It would be nice if ipcams could broadcast NDI. We’d add more cameras to our live stream if they didn’t cost $2,000 each. We could go from RTSP to hdmi but we’d still have the latency issue.
Yes-- my middle school students did a morning announcement show every morning LIVE. They wrote the script, prepared lower-third graphics plus other graphics, ran all the equipment, and anchored the broadcast. There would have been a LOT of really cool things we could have done with inexpensive IP cams.
 
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