Nov 03 2020 | NVS-25

NVS-25 Frequently Asked Questions


Matrix Switchers and Routers

If you are using a video matrix switch or video router that does not have internal frame sync or gen-lock, it's possible that your encoder is having difficulty with the source signal. When you switch to another source, the vertical interval changes, so the encoder needs to lock onto the new vertical interval, which causes the signal to appear corrupted.



Decoding Troubleshooting

There are a number of ways to decode your NVS-25 stream in a point to point setup. You can use the NVD-30 HDMI or NVD-35 SDI decoders, or you can use a computer running a compatible media player, like VLC.


Web Interface Troubleshooting

The NVS-25 uses a web-browser based interface to adjust settings, so there are a couple of things to try if you are suddenly unable to access the interface.

If you are trying to connect and login for the first time, please see the NVS-25 Network Connection Guide , the below tips are if you had previous success and a network issue no longer lets you login.

If you get a blank screen when you enter the NVS-25' IP address, please first try refreshing the web page.

If that does not resolve the issue, please note if anything changed with the software running on that computer, an update, or some other change in operation for that computer.

If that does not resolve the issue, please try a different computer or mobile device on the same local network.

If you experience a blank screen, with no menu options or error messages, you may have an IP address conflict. This can occur when you assign a static IP address to the NVS-25 that is already taken by another device on the network.

To resolve this, log into your router, look at your list of attached devices and find the IP address in question. If the listing does not have a name or ID, check the MAC Address. It should start with 00:07:, if it does not, you likely have another device occupying it. Disabling the device should allow you to access the NVS-25 again, but you may need to restart the NVS-25 and your network. The complete MAC Address is printed on the bottom of the NBS-25 unit.



Q: I recorded a .MP4 video file on my NVS-25 with the bit-rate set to 6000 Kbps CBR, and the bit-rate is lower when I look at the stats in VLC (ctrl-J/cmd-J), varying between 4800 to 5200 Kbps. Why does this happen?

A: H.264 does not natively support "true CBR" when encoding. This is not an issue with the NVS-25, but rather with H.264's overall design. CBR in this case is more like a stricter VBR setting, so the average bit-rate is closer to 6000 Kbps CBR than if you had set it to 6000 Kbps VBR.

That said, choosing CBR will generally yield a higher quality recording, along with setting a higher H.264 Profile, a lower GOP Size, and an IPPP GOP structure.

Further reading:




Q: Can we send a MPEG-TS feed sent over UDP encoded in H.264? 
I can only find a way to send it over RTSP and only as a pull and not push. I need to be able to send the feed directly to their IP. Ie. udp:// (example ip). Is this possible?

A: No, The NVS-25 does not support UDP this way.



For more on live streaming with the NVS-25, please also check out Episode 2 of our live show, Tech Corner Episodes and Resources



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