2. Me Open Source Radicalist since age 14
Early Activism: Video Game Development (for L*unix)
Mid: Multimedia Systems, Neuro-Interfacing
Recently into using technology for enabling human connection

3. The Multifactory Network
We are building a Network of Open Workspaces, FabLabs, Make[r]spaces, Hackbases...
Munich Cluster
Verbund Offener Werkstätten
multifactory.eu → Multifactory of Italy
Temp Guests: Hillhacks.in, Gulaschprogrammiernacht

4. A Window in a Wall
- A Dedicated Device for realtime Audio/Video-Communication
- based on Free Software
- Free Hardware where possible

5. Goals Minimal UI (3 buttons max)
Made from cheap components (RaspberryPi, WebCam, etc…)
Decentralized Architecture

6. Nov 2015: Verbund offener Werkstätten

7. Raspberry Pi as Videochat Platform
VideoCoreIV → Hardware Accelerated H264 Video Codec
FullHD RaspiCam available
Runs a proprietary OS that boots Linux on the ARM, and Video/3D-Acceleration → Non-Free
No Power Managment, No Audio, Problems with too many USB devices...

8. Ewindow Workshop Aug2016 WerkBox³, Munich

9. Challenges of Video Bandwidth requirements Adapt to network conditions
Re-Transmit Key-Frames
Encoder performance
Synchronization to Audio (Lip-Sync)

10. Nov 2016
HW-accelerated H264 Video streaming
No Audio
No Video Scaling

11. Audio Challenges Human perception: Unforgiving to audioo glitches
Speaker → Microphone: Echo Effect
Accoustic performance

12. Existing Implementations
SIP: linphone, Ekiga, SFLPhone, baresip
XMPP: Jitsi, gajim
WebRTC: Firefox, Chrome, [MS Edge]

13. baresip SIP Softphone implementation
Lean, Modular Code, geared towards embedded systems
Now compatible with RaspberryPi VideoCore APIs

14. Echo Cancellation Use directional microphones?
Accoustic Echo Cancellation in Software
Temporary Solution:
USB Speakerphone with Digital Signal Processor
Next Step: AEC-Shield for RPi

15. It‘s not a video-telephone
[Permanent] Link between 2 Spaces
Human Interaction between Strangers: potential Colleagues, Friends, Partners...

16. WebRTC Subset of SIP Internet Telephony Standard
Specification for RTC (and P2P Transfers) within HTML5/Browser API
Modern Codecs (H264/VP8, Opus Audio)
End-to-End Encryption
Backwards-compatibility with SIP

17. Why not just use WebRTC? Only implementations: HTML5 Browsers
We want to build a native application
Get the best performance on small, cheap Single- Board-Computers
WebRTC mandates using a centralized infrastructure (HTTPS)

18. WebRTC

19. 25 May 2017
First remote call from Hackbase India

20. Current Problems Echo Cancellation Native (OpenMAX) Video De/encoding
Raspi: USB Bandwidth issues
User Interface

21. Ende
Wobsite:
Contact:

22. PeerVPN VPN Software abstracts network connectivity
Symmetric encryption (Pre-shared Key)
Connectivity through NAT
Needs just 1 centralized „initpeer“

23. Why we are doing this
Smartphone Zombies → Virtuality is destroying our society
Building communities of real people, not just rely on technology
„Share-Economy“ is already being commercialized through we Web
We need to develop a network of skilled people
To build technologies that are currently suppressed or controlled by big multinational cooperations.
We need to learn how to share to whom

24. So what is the Ewindow?

25. So it‘s like Skype?
„The Internet“

26. Real-Time Communications
„Normal“ People rely on Instant Text Messaging since the rise of Smartphones, Facebook and Whatsapp
Skype, Google Hangouts, WebRTC-“Apps“...
HTML5 WebRTC Webb-applications
Surpisingly difficult to build
P2P at odds with centralized nature of the clear-“web“

27. Why normal people don‘t use IRC
Non-Avoidant Humans usually prefer direct (synchronous) communication → Telephone