[FFmpeg-user] rtsp streams recording simulationally (dropped frames)

[anthony20]

Hello,
i have few cameras connected to my computer (f. ex. 4). Them settings are: FullHD, 20fps, 8192kbit/s bitrate.
now i want to record streams from all that cameras to files (only video, and only direct copy).
but when i try to do it using ffmpeg i have a lot of dropped frames and lenghts of films are different from each other. F. ex. one have 1 minute, the second one have 39 seconds long.
What is the optimal settings for ffmpeg to capture those streams simulationally to HDD. I tried TCP but there are also dropped frames. Any other suggestions?