What is the frame rate and what's the I-frame interval (it may be listed as GOP or GOV also)?
That looks like artifacting from a too-long I-frame interval, especially if it's happening very regularly.
Check out ~3:12 in this video from our I-frame vs. P-frame test, where we show artifacts behind the moving train, then clear at the next I-frame.
I-frame intervals are set to 100. For some reason, the clarity of the camera was negatively affected by lower I-frame intervals. I'll have to grab test shots.
Try seting the camera for 2MP. I have heard that helps on some of the HV 3MP cameras.
Hi, try setting the iframe to match the frame rate. Also, is WDR on? Noise reduction?
What are the Quality, frame rate, and bitrate settings?
The possible cause i suspect
Option 1. Slice encoding/Decoding ( From Encoder side )
Option 2. Deblocking filter disabled at your viewer's decoder.
Option 3 : Higher GOV/GOP length.
First you can try with Option 2 and then Option 1 & 3 .