No Signal Error / Loss of signal

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No Signal Error / Loss of signal

Post by varghesesa » Wed Jul 28, 2021 1:23 pm


Not being able to connect cameras and stream correctly can be a real source of frustration. This article does a deep dive on how to resolve this one issue.

The No Signal Error can be due to so many issues, I decided to make it its own article. If you want to hear the webinar discussion associated with No signal errors, watch the Video Streaming Pipelines article. I speak about this article at the 32:48 mark of the webinar.

The Status -> Camera tab as mentioned in the BI Server Settings article maintains No Signal stats so you can easily get an idea on how big is the problem. Furthermore, Camera settings -> Watchdog allows you to set alerts when a camera losses signal. This is a good tool to understand the scope of the problem and investigate the issue at the time it occurs.


Version control

If you believe a BI update caused the issue, easy to test. If the cameras worked in the past, go to past versions and see if the cameras connect. If so, include that information with the ticket if below troubleshooting steps do not help.


Start with the Windows Tuning article. BI will not run properly if BI is in conflict with Windows.
Focus on Antivirus and Firewall exemptions. If other software is impeding the ability for BI to talk to the cameras, then of course you will get No signal errors.


I understand not everyone is able to run this test, but if you have an additional Windows machine, try running BI on that machine. It's very possible your server hardware is faulty.
While I list this test at the top of the article, this check is often tested last just because many users do not have a spare PC available.

Quote from a previous ticket.
Rebuilt the system and have all cameras working now, not sure what was the problem, but my storage has been tripled and now running the OS on a SSD so worth the effort. Thanks for all the help.
Server power settings Camera connectivity

Confirm the camera is connected to the network.

If not able to connect to camera, speak to the camera vendor for next steps.

Network Cameras

Camera hardware
Loss of signal could also be due to maybe the camera being overloaded. If you are pulling dual streams, does the fps go up if BI only pulls one stream? If you can pull the main stream or the sub stream correctly, but not both together, you may need to reach out to the camera vendor for more information.

Try a factory reset of the camera.
I was in the process of setting up the camera for remote support (opening port) and once got stuck so I did a factory reset and now I don't appear to be having the issues anymore. Weird.... I'll let it it run for a few days and see.

WIFI Cameras

FYI, WIFI SweetSpots is a tool recommended by a user to measure WIFI strengths at different locations.

WIFI Cameras are problematic and becoming more so with higher and higher resolutions. It's a lot of data to carry over the air. See customer testimonial below.
I had some wireless cams for a year or so and it was a constant issue. I tried changing frequencies and limiting frame rates and it was still problematic. Wireless is great but for cameras it's not practical yet. Just think of how much data you're trying to force in one second. Even at 5 fps with 7 cams, that's basically 35 pictures every second your trying to force though the air plus I'm sure you're surfing the web, etc. Sorry to bring you bad news but the bottom line is Wi-Fi cameras all lose connection. Even a lot of cheap Chinese wired cameras drop out a lot. you just have to live with the "lost connection" Alert.
While working one ticket, a user had 12 WIFI cameras: some indoor, some outdoor, different manufacturers, 2 MP or 5 MP all using 2.4 GHz WIFI. The user did not want to replace all his cameras. Instead he installed 2 BI servers, thinking his BI servers were overloaded. No impact (11 cameras is generally a trivial load for BI software). He then decided to install 2 routers thinking he could distribute the traffic across routers. No impact, there was still the same noise on the airways.

The fix: The user was able to convert 9 of the 12 cameras to PoE.
I took your advice, did the research, and converted 9 out of my 12 cameras to PoE from wireless. Their stability increased to such a great degree that I (gradually) combined all of them onto one license (on a used laptop dedicated to BI). I then did a little bit of tweaking their frame rates and bitrates.

The stats look pretty good to me and the stability seems close to perfect. That has resulted in good news and bad news. Good: You came through for me and now my Blue Iris setup is in great shape. Bad: I now only need one of my two licenses, so I will not be renewing one in a few months.
In case anyone is wondering how to convert WIFI cameras to PoE cameras, from the user:
  • I bought a PoE switch. This one has 4 ports but you can daisy chain another one off it. Or you can get switches that have more ports. Either way, you must have the switch connected to your router, and then all of your cameras must connect to a switch.
  • For each camera, I bought an active PoE splitter. It is inserted between the camera connections (power and ethernet connectors) and the ethernet cable that comes from your switch.
That’s all there is to it. There are some restrictions, such as a max of 300’ of ethernet cable between a switch and the camera, and you have to be aware of the wattage required by your camera to make sure your switch can power it, but that’s about it.

*** Camera, Network equipment, and Windows have been ruled out. ***

BI Server Settings

Camera connector

IP Config Dialog
At this point, we ruled out the computer hardware, the network and the camera hardware/settings. The only settings left to check are the IP Config dialog connector settings to the camera.

Walk through the Connector article beginning with Step 2.

Revisit your settings.
  • Make/Model = ONVIF/Generic. Works?
  • Make/Model = <Camera vendor>/<Model>. Works? (did you try all the models to see if any works?)
  • Make/Model = Generic / VLC. Works?
    If the camera works using VLC, try the VLC option in BI. This tells BI to use the VLC stream parser. Otherwise, BI uses its own stream parser.
    live view vlc.png
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Camera stream

Time to investigate the video pipeline.
Video path: Camera video/feed -> Decode -> Console view (fairly simple path)
Simplify the video pipeline.

Video path: Camera video/feed
First what are the camera stats? Camera settings -> General tab
Are the stats lousy, e.g. 1 fps?

Set camera to simplest encoding possible, e.g. H.264 Baseline or Main.
The Camera setup article has details.

Video path: Decode

GPU / Hardware Incompatibility
There is nothing more frustrating than doing a BI update and all your camera streams stop. Many users state the BI Update caused the issue. Sharing this story because it's easy to place fault. The below was a real ticket. :) The customer was convinced the issue was with the BI update until proven otherwise. The issue was due to a Windows update.

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Rolling back to the previous version or last stable version did not resolve the issue. The customer was convinced the issue was with the BI update. Instead of trouble-shooting, he waited for the next update, hoping for a fix.

Unfortunately, no fix came. The customer then revisited my trouble-shooting email a few weeks later. I first asked the customer to turn off cameras and to observe whether other cameras started working. I suspected the CPU was being overworked. No improvement after disabling all the cameras but one.

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My next suggestion was to turn off hardware acceleration. After doing so for the non-working cameras, all came back online!
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We suspect the root cause was probably a Windows update or GPU update that disrupted the camera streams. Moral to the story is BI is dependent on many external drivers and software. All these 3rd party dependencies can lead to instability. Second take away is turn off hardware acceleration if a camera or group of cameras constantly has no signal and see if issue goes away. Hardware acceleration is one of the few settings that can affect many cameras at once.

FYI. The software now turns off HA automatically for a camera if it determines the stream is not compatible and this is logged to Status->log as well.

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If you want to fix the problem, you can go to the camera settings on the camera and adjust the encoding to a more simple format.
See Camera settings article for details.
Or wait for the next driver update that may fix the issue caused by the current driver.

The BI Server Settings article details ALL the server settings that can affect the video stream.

Final tests

Understanding the logs is key to understanding the server.

Isolate issue
Narrow down the issue by turning functionality off. Turn the shield from green to red. The red shield turns everything off, e.g. recordings, alerts etc. The cameras remain connected and stream live video. Do the cameras start working again? This could imply the CPU is overloaded when running normally, i.e. storage, remote connections, triggers and alerts etc are enabled.

Temporarily disable all the functioning cameras. Do the non-working cameras start working again? Another indication that server resources are causing the issue (CPU, disk, RAM, ethernet card etc).

You may also want to consider deleting and re-adding the camera. I have customer testimonials stating their skepticism to doing so but it has worked on occasion. Some mysteries with Windows and software will never be solved.

Next steps

If you have read to the bottom, the cameras still do not connect.
Put the camera on the WAN for remote testing.
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