zerocam

Python based interface for the pi zero w for timelapse videos and live streaming

Used Hardware

• Raspberry Pi Zero W
• Offizielles Raspberry Pi Zero Gehäuse
• Raspberry Pi Kameramodul v2
• Adafruit I2S MEMS Mikrofon-Breakout - SPH0645LM4H
• Tactile Button switch (6mm) x 20 pack

System Info

User & Password

• Linux - pi:raspberry
• Django -

Access Point

• SSID: zerocamap
• Password: zerocampw
• static ip: 192.168.4.1
• dhcp-range: 192.168.4.2 - 192.168.4.20

URL's

• hostname
  • zerocam
  • zerocam.local
• livestream
  • Django: http://zerocam.local:8000/static/video/index.m3u8
  • nginx: http://zerocam.local/hls/index.m3u8
  • node-rtsp-rtmp-server: rtmp://zerocam.local/live/picam
• webinterface
  • Django Landing Page: http://zerocam.local:8000/video/

.service files

picam.service | start picam streaming
django.service | Django Webinterface
gpiobutton.service | listen for button press and shutdown pi or activate access point
picam-ramdisk.service | create ramdisk folder on startup

folders

• testing: code snippets and testing of modules
• script: mainly setup and startup scripts
• media: folder for videos, images, timelapse, etc.

Setup

Basic Raspberry Setup

• Set shared Memory to 256mb
  Needed for picamera pictures with highest resolution

ffmpeg installation (with hardware acceleration)

https://github.com/legotheboss/YouTube-files/wiki/(RPi)-Compile-FFmpeg-with-the-OpenMAX-H.264-GPU-acceleration https://www.reddit.com/r/raspberry_pi/comments/5677qw/hardware_accelerated_x264_encoding_with_ffmpeg/ https://askubuntu.com/questions/87111/if-i-build-a-package-from-source-how-can-i-uninstall-or-remove-completely

Delete previous version of ffmpeg: sudo apt-get remove ffmpeg

Install checkinstall: sudo apt-get install checkinstall

Download and Compile ffmpeg with Hardware Acceleration on Raspberry Pi:

cd /home/pi/
sudo apt-get install libomxil-bellagio-dev -y
git clone https://github.com/FFmpeg/FFmpeg.git
cd FFmpeg
sudo ./configure --arch=armel --target-os=linux --enable-gpl --enable-omx --enable-omx-rpi --enable-nonfree
sudo make
sudo checkinstall

You can remove it from your system anytime using:
dpkg -r ffmpeg

If an error occurs when running checkinstall try:
sudo checkinstall --fstrans=no

ffmpeg with mmal support (probably not needed):
https://maniaclander.blogspot.com/2017/08/ffmpeg-with-pi-hardware-acceleration.html
sudo ./configure --arch=armel --target-os=linux --enable-gpl --enable-mmal --enable-omx --enable-omx-rpi --enable-nonfree

Programming

TODO

• Django Webinterface
• HotSpot
  • Aktiviern über Button
  • Script um zwischen AP und Wifi zu wechseln
  • Change /etc/hosts with script (add 192.168.4.1 and comment out 127.0.1.1)
• WiFi
  • aktivieren über Webinterface
• Stop-Motion Push-Button (in webinterface)
  • https://projects.raspberrypi.org/en/projects/push-button-stop-motion
• Timelaps Videos

Python

1. pip3 install --user pipenv (required)

Django

Setup Project(for Documentation only)

1. pipenv install
2. Projekt erstellen django-admin startproject zerocam_ui
3. In zerocam_ui Ordner wechseln
4. pipenv shell
5. Django App erstellen python manage.py startapp wifi_setup
6. Anleitung befolgen https://docs.djangoproject.com/en/2.1/intro/tutorial01/
7. Admin User erstellen python manage.py createsuperuser

Run Application

1. cd zerocam/
2. pipenv install
3. pipenv run zerocam_ui/manage.py runserver
4. Enjoy

Livestream

-- Symlink anlegen damit django die Files ausliefert ln -s /run/shm/hls /home/pi/zerocam/zerocam_ui/wifi_setup/static/video

Commands for Testing

picam

picam with hls streaming / framerate 25 / volume gain 10x:
/home/pi/picam/picam --alsadev complex_convert -o /run/shm/hls -f 25 --volume 10
picam with timestam
/home/pi/picam/picam --alsadev complex_convert -o /run/shm/hls -f 25 --volume 10 --time
picam with timeformat "2018-12-01 12:30:05"
/home/pi/picam/picam --alsadev complex_convert -o /run/shm/hls -f 25 --volume 10 --time --timeformat "%F %T"

ffmpeg

Create timelapse from jpg
ffmpeg -framerate 10 -pattern_type glob -i '*.jpg' -r 25 timelapse10.mp4
Create timelapse with hardware acceleration
(Change -framerate value to your needs)
ffmpeg -framerate 10 -pattern_type glob -i '*.jpg' -c:v h264_omx -b:v 4000k -r 25 timelapse10.mp4

systemd

https://www.digitalocean.com/community/tutorials/how-to-use-systemctl-to-manage-systemd-services-and-units

check if service is active
https://stackoverflow.com/questions/30056280/test-if-a-systemd-unit-is-active-in-a-bash-script
systemctl is-active picam.service
check if service is active (only exit-code):
systemctl -q is-active picam.service

Reference

picamera

https://picamera.readthedocs.io/en/release-1.13/index.html

i2s mems mic

mpromonet/v4l2rtspserver#94 (comment)

Power Button

https://howchoo.com/g/mwnlytk3zmm/how-to-add-a-power-button-to-your-raspberry-pi

Programming Basics

Efficency of while loops

• While: pass
  Bad. 100% CPU

• While: time.sleep(1)
  Better. CPU every 1 sec

• While: Event().wait()
  https://stackoverflow.com/a/48631852
  Python 3.2+ / No Windows / No CPU time

• While: GPIO.wait_for_edge
  https://howchoo.com/g/mwnlytk3zmm/how-to-add-a-power-button-to-your-raspberry-pi
  when using while loop to wait for gpio but can't be used with GPIO.add_event_detect

if conditions

• Check if variable contains string
  https://stackoverflow.com/questions/3437059/does-python-have-a-string-contains-substring-method
  if "string" in variable:
if "string" not in variable: