I have a rather weird issue. My aim is to use ffmpeg to grab a screenshot from a home CCTV cameras rtsp stream every hour. I want to do this in order to make a timelapse. However everyday from 11am to 12am (the next day) there are no snapshots saved.
On an always on Debian machine, this is the shell script I have that crontab calls:
dt=$(date +"%d%m%2y%I%M%S")
ffmpeg -rtsp_transport tcp -i "rtsp://IP:554/..." -frames 1 /user/snapshots/ch1/$dt.jpg
Running it by itself works fine and saves a jpg snapshot successfully to the right folders.
In crontab -e I have the following line:
0 * * * * /bin/sh //user/snap.sh
Thanks.
%I is the hour on a 12-hour clock (intended to be used with %p), so your afternoon files are overwriting the morning ones. Use %H instead.