thread pipeline task

[vladak]

Here's an idea I got from a (unanswered) stackoverflow.com question:

• there is a processing step that requires N stages however cannot be completed in given time slot
  (think soft-realtime system such as video processing) so each stage will be performed in each slot
  at the expense of N slot delay (which is normally acceptable e.g. when doing 1/30 frames and N <= 6 - people usually don't recognize difference between 24 frames/sec and 30 frames/sec)

  • implement a "clock" thread that will present the results and N processing threads

    • each thread will get an item and perform the next stage of processing.
      If the item reached final state, it will be handed out to the "clock" thread.

  • design the API so that this is useable as a library

• the item can be typedef'd so that it serves as a wrapper of another data structure (void *)