I am trying to create a dashcam from an RTSP streaming device using ffmpeg (in Python). I have it working, but I am losing a small bit of video between stopping a file and starting a new file.
My pseudocode looks like this:
Start recording in 5s increments
while True:
now = get current time
if now > split:
stop recording
start recording with new file name
At any point when I send a trigger, I wait (up to 5s) for the current file to be written to disk, and then I stitch the required number of files to get a video of the desired length. The issue is that I am losing time between the stop and the start.
I am starting a new file like so:
process_cmd = "ffmpeg -y -loglevel panic -i rtsp://{}:{}@{} -vf scale={}:{} -t {} {}".format(self._rtsp_login, self._rtsp_pwd, self._rtsp_server, self._width, self._height,self._rtsp_video_duration,output_file)
self._process_handle = subprocess.Popen(process_cmd, shell=True)
I am waiting for the video to be done recording by:
self._process_handle.wait()
What's a cleaner way to do this? One option would be to write a longer file and then use ffmpeg to extract the desired N seconds from it.
proc = subprocess.Popen("ffmpeg -y -i rtsp://admin:ambi1234@192.168.1.200 -profile:v high -pix_fmt nv12 -b:v 15M -acodec aac out.mp4", stdin=subprocess.PIPE,shell=True)
This requires me to stop the recording first by sending 'q' to the process and then:
subprocess.Popen("ffmpeg -y -sseof -00:00:3 -i out.mp4 -vcodec copy -acodec copy test.mp4", shell=True)
But that source file (out.mp4) would have to be cleaned up every so often and if an event happens at that point, then I won't be able to capture the data.
