Rows of "Big Pixels"

[do_lai]

Hello.

I attempted to e-mail tech support, but the web form would not let me through.

I own an IP2M-850EB and two IP4M-1055EW units. I appreciate the value for quality, but am having an intermittent issue with apparent corruption of the video stream and I was wondering what I need to to to correct this, settings-wise (either on the camera or on ingest).

Intermittently there are rows of large "pixels" that take several seconds to clear. See attached file for an example. These usually occur in the top third of the image. They occur more frequently at higher resolution. They are wreaking havoc with my motion detection.

Stream is being ingested by a ZoneMinder server. Settings are: 10 fps, 1080p, Ffmpeg, rtsp://user:pass@ip:554/cam/realmonitor?channel=1&subtype=0, 24-bit color. For diagnostic purposes, only one monitor enabled at a time. Stream is about 1.2 Mbit/s, well under link saturation (gigabit network). The system is not being taxed, about 5% CPU utilization for the monitoring.

Reproduced on a second server and does not occur with five other cameras from several other manufacturers.

Camera-side, H.264H, 1080P, 10 fps, VBR, 6, 2048, 20.

Any recommendations would be appreciated.

[do_lai]

I was able to get the two IP4M-1055EW units to not exhibit this behavior with H.264H, 1080P, 10 FpS, VBR, 6, 1536, and key frame interval of 10. It improved decreasing the key frame interval from 20 to 10 and seems to have been eliminated altogether with the decrease of stream limit to 1536 Kb/s. If I increase this value, the problem reoccurs, even if I leave the key frame interval at 10.
I was able to keep the FpS on these at 10, but had more trouble on the IP2M-850B: had to decrease the FpS to 7, drop the bit rate to 1280, and drop the key frame interval to 7. I do occasionally see the artifacts, but much less often.

How can I improve quality while avoiding the artifacts? The cameras should be capable of better according to the specs.

Thanks.