There is an instruction how to calculate Breathing rate in Python by Talha Iqbal on Youtube:

The code used is adopted from HeartPy:

https://github.com/paulvangentcom/heartrate_analysis_python

developer: Paul van Gent, Delft University of Technology, Niederlande:

https://www.tudelft.nl/en/ceg/about-faculty/departments/transport-planning/staff/personal-pages/gent-p-van?0%5BL%5D=1&cHash=657dd242c1919da5bced7d8dfdc0b979

You can also offer Paul van Gent the job for a real-time respiration monitor in Python, if you have a lot of money. I suppose it is a full-time job:

https://www.linkedin.com/in/paul-van-gent-3b5b5817/?originalSubdomain=nl

HeartPy is Paul van Gents winning paper:

https://scholar.google.ch/citations?user=OOhuA6gAAAAJ&hl=de

MQTT for Python:

https://pypi.org/project/paho-mqtt/

26.3.22 9:25

At least three PhD worked on Respiratory Rate from PPG or ECG signal, Paul van Gent, Peter H. Charlton, Gaelle Prigent. I could not find a real-time respiration monitor device from those. Only Garmin/Firstbeat has one:

Respiration Rate measured with Garmin watches?

Don t trust the miracle devices from Firstbeat or Garmin.