# Technical details

## Performance

Webinars are performed on location
in front of a live audience.

## Stage

The stage for the webinars is the trunk of a van.

The van is parked during the performances,
at select places in Århus and Copenhagen.

## Recording

During each webinar, audio and video is captured and mixed.
The live-mixed recording is presented on location as part of the webinar,
and also broadcast live to remote spectators,

### Capture

### Mix

### Stream

[[!template id=alert context=danger content=<<ALERT
 * Must save recording to disk, before compression and streaming
 * Must survive exceeding bandwith (fixed or varying) towards broadcast host
ALERT]]

[[!template id=alert context=warning content=<<ALERT
 * Should log telemetri of streaming host
    * Machine temperature
    * Machine speed
    * Processing (speed, utilization)
    * Disk (read speed, write speed, space available)
    * Network (bandwidth consumption, data loss, response time, radio signal quality)
    * Compression (input format, output format, output size, latency)
 * Should handle varying bandwith towards broadcast host
 * Should optimize compression
 * Should configure and test fallback radio link
 * Should measure archival storage needs
ALERT]]

[[!template id=alert context=info content=<<ALERT
 * Maybe embed countdown into video image
 * Maybe embed logo as watermark into video image
 * Maybe dynamically adjust compression to match varying bandwith towards broadcast host
 * Maybe test analog video input (for emergency fallback)
ALERT]]

### Broadcast

[[!template id=alert context=warning content=<<ALERT
 * Should log dynamic IP of streaming host
 * Should log telemetri of broadcasting host
    * Machine temperature
    * Machine speed
    * Processing (speed, utilization)
    * Disk (read speed, write speed, space available)
    * Network (bandwidth consumption, data loss)
    * Distribution (open sessions, latency)
ALERT]]

[[!template id=alert context=info content=<<ALERT
 * Maybe log geolocation of streaming host
 * Maybe gracefully handle varying bandwith towards users
ALERT]]

### Play

[[!template id=alert context=danger content=<<ALERT
 * Must keep audio and video syncronized (lipsync)
ALERT]]

[[!template id=alert context=warning content=<<ALERT
 * Should test dedicated (non-web) players
    * mpv
    * vlc
    * bowser
    * Default player on Windows
    * Default player on Windows Phone
    * Default player on OSX
    * Default player on IOS
    * Default player on Android
ALERT]]

## Website

The website <https://omni-presence.dk/> documents the work.

### Styling

User interface and user experience is done mobile-first
using the Bootstrap framework,
with an aim of creating a conventional modern business feel.

[[!template id=alert context=warning content=<<ALERT
 * Should warn user if browser does not support live code (javascript)
 * Should suggest driver install when browser does not support live media (WebRTC)
 * Should warn user if browser fails to activate live media (WebRTC)
 * Should document use of dedicated (non-web) players on webinar page
 * Should hide notes on tech page by default, showing only when pushing a button "Display internal notes" at bottom
ALERT]]

[[!template id=alert context=info content=<<ALERT
 * More than one testimonial (where exactly?)
 * Maybe fixate footer at bottom
 * Maybe better match footer with other styling
 * Maybe place countdown on top of video image
 * Maybe place front page webinar teaser at top for all devices (not only large ones)
 * Maybe add animation (e.g. slide in from right) for front page webinar teaser
 * Maybe have front page top intro fill whole width and without space at top
 * Maybe use carousel for front page top intro
 * Maybe add countdown to front page webinar teaser
 * Maybe add space above contact form
 * Maybe show geolocation of streaming host on webinar page
ALERT]]

### Interaction

Fedback form is provided.

[[!template id=alert context=info content=<<ALERT
 * Maybe send contact form data as email
 * Maybe extend contact form (expanded during fill-out of the form)
 * Confirmation message when comment sent with human confirmation
 * Error message when comment sent without human confirmation
 * Where does the comment emails go?
 * What is the interaction from there?
 * CGI @xayide or mail @morla
 * data security
 * form.omnipresence.dk?
ALERT]]