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Welcome to the PTZOptics forum(s)!

This thread has been created for end users to discuss the topic of differences between NDI and NDI|HX and when it is best to use each option.

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There are two (2) major considerations when contemplating using an NDI vs an NDI|HX source

  • bandwidth 
  • quality

So let's start with bandwidth... one of the major advantages to using NDI|HX is the lower bandwidth consumption presented by the HX source.

If you look at bandwidth consumption for NDI versus NDI|HX you will see, on average, an eight (8) fold increase in bandwidth consumption.

If we take a moment to look at this in a real world application where we have a 1 Gb bottleneck in our network we would be limited to less than ten (10) NDI sources.

Now if we look at that same 1 Gb bottleneck using NDI|HX we can still pass approximately eighty (80) NDI|HX sources via that same connection.

Having the lower bandwidth consumption allows you to be more flexible with your deployments.

Now let's chat about the differences in quality between NDI and NDI|HX

The additional bandwidth consumed by NDI is not for nothing; you do gain an improvement in the color space as well as a mostly uncompressed video feed.

For high budget productions, archival purposes or post production scenarios using NDI may be a better fit due to the higher quality of the video to work with.

When looking at NDI vs NDI|HX or even your production at large one of the considerations that needs to be made is "HOW are my end users going to consumer this content?"

If your are using YouTube or Facebook then there isn't much reason to bother with super high resolutions and super high frame rates... as they will be lost in translation to the platform and possibly make the production less reliable.

This can be things such as taxing the production PC or requiring a large reliable pipeline for streaming your production out when using these high quality feeds.

If the platform even supports those higher resolutions and frame rates how your end users are consuming the content can be another key factor to consider

If the end users are viewing this on their mobile devices there is little point in making a 4K production; even if they are viewing them on their home PC it is unlikely they would want to watch in 4K unless you give them a good reason.

These are just some initial thoughts on NDI vs NDI|HX and I look forward to any input our community wishes to add to these discussions on an ever evolving topic.

I think there is another variable for NDI vs NDI HX comparison: latency.

From my reading different forums, I'm getting, that going with HX  introduces 40-50 ms latency. Not sure, if it's true.

So, is it possible to switch PTZOptics camera to NDI (non HX) mode?

I see, that I can set "NDI Preset" to "Off", but "First stream" is still set to "H264".


NDI HX latency from the cameras should be around the 200 ms mark. The cameras do not offer a "Non HX" NDI mode. The cameras still uses H264 for its compression method for RTSP and RTMP, as well as NDI. The NDI preset is just a collection of settings for the first and second stream to utilize the correct settings for different, preset, NDI resolutions and framerates. 

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