Recent content by Sergey Kandaurov

I downloaded new firmware from 海康威视是以视频为核心的物联网解决方案提供商 (X series) and it seems to fix the problem.

Yes, somehow the camera firmware feeds the same data two times to TCP. Or camera's TCP forgets to clear a buffer. In any case - it's camera firmware problem, and with no firmware updates available for the camera it looks frustrating.

Yes, I tried connecting the camera directly to PC with a different cable - same result. I guess that 1000mbps has less problems compared to 100mbps just because it's faster - less time to transmit a file means smaller chance that it runs in conflict with something, or less data in buffer because...

I tried connecting the camera to another Gigabit switch - same issue, just less frequently (about 1 in 30). TCP is designed to deliver the correct data (or don't deliver it all). If the camera is duplicating data in the TCP stream - it sounds like a critical bug in camera firmware to me.

I've just bought a cheap "gray market" Hikvision camera DS-IPC-B12H-I. It has V5.5.71 build 180828 firmware and chinese UI (I can live with this). I've discovered problems with getting corrupted H.264 stream via TCP (fails to play sometimes and ffmpeg shows errors). But what's more worrying is...