The video is corrupt so it doesn't appear to be a stuck IR filter; I'd say it's a video encode/decode issue between the cam and the NVR.
Assuming you've restarted both and no good results, can you:
- Move the cam to a different NVR port?
- Swap the cable that the cam is on?
- Hard reset the cam and re-install it to the NVR?
Also, does this happen as the temperature gets hotter, such as 90 degrees F about 1300 hours?