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Revision as of 14:50, 4 August 2019 by Beadsland (Talk | contribs) (Further Stages)

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Github icon.jpg Github Repository | Bricodash screenshot.png A Bricodash Sub-Project | Beads Land-Trujillo.jpg A Beadsland Creation

Concurrent frame-scrubbing multiplexing webcam gateway daemon.

Devoted service to stream doorcam and spacecam to Bricodash and public gateway, respectively, while tracking activity and performance of these and other webcams at the space. Will be more efficient and reliable than spawning PHP and Python processes on an as-they-come basis.

Written in Elixir, will be taking advantage of various new features of the language, building on the strengths of Erlang/OTP, including Mint (web client), GenStage (backpressure event pipelines) and ultimately mix release (build-time deployment packaging).

Current project plan:


SnapSource Stage
  • revert changes
  • ignore backpressure, just dispatch events from task loop
  • test grab a batch
  • catch dead cameras rather than erroring out repeatedly
Broadcast Stage
  • test grab a batch
Further Stages
  • consumer-producer to check for bad frames
  • consumer-producer to queue multiple events into single batch event (handle_demand)
  • retool bad frames checker (handle_events):
    • max_demand/min_demand: 2/1
    • task_async over each batch event
    • unbatch result to dispatch as list of events (ignore backpressure)
  • consumer to flush and track quality
  • web consumer as Task
  • web consumer poolboy


  • implement stream as snapshot flipshow
  • ensure recovery when flipshow fails
  • reimplement stream to consume source stream
  • ensure recovery when source stream fails


  • provide for throwing timeouts
  • implement greytoss checking
  • configure to launch as daemon
  • bootstrap to obtain dependencies and compile cold
  • incorporate sous veil / swap out PHP touch points
  • incorporate upt chk / swap out Python CGI touch point


  • investigate periodic multi-hit events: server severing connections prematurely? badly behaved client device?
  • investigate specific issue of pishop launch causing multi-hit failures on all other clients