Video quality shift/blip/pause every 3 seconds

[simtimpson]

I have 5 current (but different) model Amcrest IP cameras and 1 old Foscam. While watching the live video (and recorded video) from all Amcrest cameras there is a quality blip/shift every 2 seconds or so. This doesn't exist with the Foscam. The Foscam is clear as day. All the Amcrests very slightly blur/shift every 2 seconds. This happens indoor, outdoor, day, night, doesn't matter.

It's not a lag/delay when there's motion. It's a shift in video quality. Example: It's like everything gradually gets lighter, then blips back to being darker and slightly sharper, every 2 seconds, over and over forever. It's very annoying.

Also, the cameras do it on a different cycle.

What is this, and why does it happen?

[Melvin]

Hello simtimpson,

It looks like the camera is trying to auto fix the exposure, light changes. Login to the cameras' web interface and go to set up > Camera > Configuration. Here, please try changing the BLC mode to HLC and try adjusting the values manually on one camera to see if that helps. Also you can set the mode for Exposure to manual and adjust the value.

[Seamless]

What you are seeing is the I-frame in the compression scheme cycling, by default is it set to double the frame rate, so every 2 seconds you get an I-frame, and then all other frames between are calculated based off that high quality frame. You can experiment with the setting and the bitrate to try to reduce the quality drop, but the lowest you can choose for a setting is at the frame rate. (30fps would be 1 I frame every 30 etc) Hope this helps!

[simtimpson]

Thanks for the info! It is/was the I-frame. I now understand what it is/does. It will always be there but I adjusted/lengthened it and it’s much more palatable.