pulsing recording quality.

GFM

GFM

Getting the hang of it
Sep 9, 2016
110
36
Center of Canada
Noticed over this last week or so the recording quality (when cams are triggered) varies during the recording. Image seems to pulsate between normal quality to extremely low quality pixelated video. This cycles every 2-3 seconds.
I did change some audio settings in BI but I didn't notice the recording issue after doing that; at least right away. Backed out of those changes and the issue continues. Also I may have re-booted the system and allowed BI to update about when I noticed this issue.
Cameras play perfectly in the BI GUI, issue only when viewing recordings.
CPU load on this PC is normally quite low often less than 5% but can creep up when running other processes to 40-50%. It's an I7 with 16GB ram. BI V 5.3.2.11x64 2020.09.25 which indicates it may not have updated.
Doesn't seem to make a difference if the LAN is loaded up or not, it's all wired GB except a few cams that connect to the lan wirelessly through wireless AP/Client radios. These record the same as the other cameras so I don't "think" it's network related, unless I am having router issues (updated firmware since, made no difference).
Any ideas where I should be looking? Camera settings, recording quality, etc...?

Tnx,
-G.
 
Make sure you have direct-to-disc recording enabled, and record to "BVR" format (not MP4 or AVI or anything else).

If the above doesn't solve the issue, then screenshot your camera's video encoding settings in its web interface, and if possible, provide a video sample.

My theory is that you might be having the "Pulsing" or "Shifting" video problem as described here but the way you word it makes it sound rather extreme, and usually this problem is subtle. That is where the video sample might help.
 
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Thank you for the reply. Yes that particular camera had been set for MP4 instead of direct to disk.
Here's a video in .bvr format, zipped. This is before changing settings back to "direct to disk".
 

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@GFM ok, yep, I was exactly right with my guess. What it boils down to is that Blue Iris isn't very good at re-encoding video clips, so you see significant quality loss unless at every new i-frame unless you use a very high bit rate for the re-encode. The simple solution is to enable direct-to-disc recording. I went into much more detail in the article I linked in my previous post.

I encourage you to check out this page Optimizing Blue Iris's CPU Usage and follow recommendations there as well.
 
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Actually all my cameras were set for re-encoding. I suspect this is a default setting. Changing this has eliminated the problem.
Many of the other recommended settings have been implemented already such as limiting cameras to 15fps and others in the linked page.
Thank you for your help! Very much appreciated!
-G.
 
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Now I notice my cameras are not triggering/recording properly. Often they will trigger after the movement has left the frame and all I get is a few seconds of audio of a vehicle moving off or footsteps. Not sure if this is due to changing any of the recording settings as done above, seems to have started doing this after changing those settings.
Now I regret changing settings from default, it was working fine before changing audio settings maybe a month or so ago.
The cameras' audio is much better now though...
 
GFM said:
Now I notice my cameras are not triggering/recording properly. Often they will trigger after the movement has left the frame and all I get is a few seconds of audio of a vehicle moving off or footsteps. Not sure if this is due to changing any of the recording settings as done above, seems to have started doing this after changing those settings.
Now I regret changing settings from default, it was working fine before changing audio settings maybe a month or so ago.
The cameras' audio is much better now though...
Click to expand...
When using direct to disk blue iris can only begin recording on a new iframe. Make sure you cameras iframe interval is set to match your frame rates or at most double your frame rates. Ensure you have a few second of pretrigger recording setup.
Your prior settings were terrible both for pc efficiency and recording quality. Using direct to disk is the way to go.
 
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I'll have to look into this Iframe interval. maybe I'll get it working eventually! :)
Pre-triggers are set for 2 seconds, maybe I should try 4 and see how it works?
Thanks for your insight @fenderman!
 
Iframe was set to 15 on most of the cameras so I changed to 60. Is there a way to determine the optimum settings for each particular camera other than guessing looking at the video quality during playback?

Most of my cameras are Dahuas, but I can't find an Iframe setting in the older Foscam units. Guess they are as good as they get using what ever is default.
 
In BI the iframe rate should match the frame rate. Allows motion detection and start of event timing work properly. If you're using substreams, the rates in the substream, frame and iframe, should match the mainstream.
 
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GFM said:
Iframe was set to 15 on most of the cameras so I changed to 60. Is there a way to determine the optimum settings for each particular camera other than guessing looking at the video quality during playback?

Most of my cameras are Dahuas, but I can't find an Iframe setting in the older Foscam units. Guess they are as good as they get using what ever is default.
Click to expand...
Why sixty? at most it should be double, but matching the frame rate is prefered.
 
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So a frame rate of 15 should have Iframe set at 15, where it was? Should I increase the frame rate to 30 and drop Iframe to 30 as well?
I have 16 cams on the network. It's a gigabyte network but I might start losing headroom if several cameras happen to trigger at the same time I am thinking. Maybe I should go with 15fps and an Iframe rate of 30? Or maybe compromise and set a frame rate of 20 and Iframe 20 if matching frame rate and iframe are desired?
This is the only time I have delt with iframe rates on the camera config settings so I am learning as we go. Thank you for the help in configuration.
-G.
 
security cameras should run at 15 fps. There is no need to run any faster for normal security. In a normal configuration all traffic from all cameras go to Blue Iris for processing. So the network load does not change. 16 cameras at 15 fps will not come close to using a Gigabit (1000 megabit) network . Most movies are at 24FPS. At 15FPS use an Iframe of 15 (1 second) or 30 (2 seconds) .

Sixteen 2 MP cameras running at 15 FPS using h.264 compression is less than 5 megabytes (40 megabits) with normal motion and colors.

In BI the frame rate and Iframe values can only be set in the camera directly.

A smile explanation of frame and Iframe in security cameras. If a frame rate is 15 and and Iframe is 15, 1 complete frame is sent even second, and 14 frames are sent with the data that has changes. The amount of data sent for the 14 frames depends on the motion, color differences and compression (h.264 and H.265) . The more compression the high the processing demand at the camera and at the BI PC.

What is you BI PC CPU type and Memory.

Please provide a few shot from your cameras video configuration screens in your camera, it should contain the frame, iframe, quality, maxbit rate, resolution, video encoding....
 
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BL Hadware:
Intel i7-4790 @ 3.60GHz, 16GB ram.
OS- Windoze 8.1

Here's one of the Dahua camera video setup screens:
1606601062274.png
 
As you are using H.265 on a I7-4790 which is not supported on the quicksync for that codex

I run the same intel processor i7-4790 with 16GB on Windows 10 with no problems. I run headless. I use H.264 on all cameras. In BI I use use intel acceleration.
I do not know about the graphics drivers on windows 8.1

I would recommend doing a Windows 10 clean install using "microsoft media creation tool" .
Set all outside cameras to 15 fps and Iframe of 15 and use h.264. I use a bit rate of 3072 kb/S and VBR.
I use continuous recording direct to disk in BI of all cameras.
 
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@SouthernYankee,
Updated settings as you indicated, will see how works. Didn't do the OS upgrade though, will see how works without.
Video looks good so far. Will see how well it triggers.
Continuous video seems like a lot of data, but I suppose a 500g hard drive would be ok FIFO should keep a week or so.
We usually travel in the winter, not so this winter by the looks of it. Nice to keep track of things back home when gone.
 
You'll need far more than 500 gigs for a weeks worth of 24/7 recording. 4TB would be more like it depending on how many cameras, resolution and so on.
 
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