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Requirements for Awedio (pronounced aw - dee - oh)
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Description/Background
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a DJ/programmer and i were discussing the possibility of creating a
more universal interface to sound to coincide with the tide of digital
media as a replacement for physical media. originally conceived as a
nice tool for DJs spinning purely digital sound at raves, parties,
radio stations, etc., Awedio became conceived as a more universal
tool. it is now envisioned as a generic I/O system for as many audio
formats as the developers feel like implementing, as well as a generic
processing system, where the processing sits at a plug-in level between
Input and Output.

Criteria/Features
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* well-established I/O:

  the goal here would be some sort of streams-based design. an input
  signal can be considered a stream. there should be the option of
  allowing multiple input signals from a wide variety of sources (e.g.
  mp3, aiff, live feed, MIDI).

  output would be much the same. we should be able to provide output in
  any desired format. initially, the priority would be to simply
  provide a sound signal, but we would want to be able to produce any
  sort of file format or streaming audio, as well, plus options for
  multiple signals for things like 4.1 sound systems (or even basic
  stereo).

* robust signal processing:

  this has lower priority than basic I/O. without any processing in the
  middle, signals should just flow in and out of the system. the
  possibility for a drop-in processing module would allow for just
  about any signal processing imaginable (e.g. reverb, flanging).

  additionally, the final implementation should support basic
  sequencing functionality. users should be able to create loops, for
  instance.

* real-time processing:

  this would require not only solid processing algorithms, but also
  intuitive accompanying interfaces. sometimes we would want to present
  turntables or sliders or graphics mimicking systems with which audio
  engineers are already familiar.

core requirements
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* processors:

  a standard player interface. this is something that would correspond
  to traditional virtual CD players (e.g. xmcd, Apple CD Audio
  Player). it would provide standard functions such as Stop, Play,
  Pause. with a generic queueing function implemented, functions such
  as Skip Track and Back Track (i.e. fast forward and rewind,
  respectively) would make sense in this context.

  also, in keeping with the tradition of the origins (i.e. a DJing
  system), it would be nice to have a turntable interface to provide
  realtime scratching capabilities. maybe the DJ module could be
  extended to provide support for beat matching.

* file formats:

  at the least, file formats we should support are mp3 and aiff. it
  would be nice to support MIDI input and streaming audio (e.g.
  RealAudio). these should be supported in both the input and output
  modules.

* channels:

  we should support mono and stereo signals in the initial prototype.

testing
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testing would involve first testing the input channels by verifying
that signals are coming in as expected. once input is successfully
working, it would be necessary to try sending output to as many sources
as were implemented. once the I/O is thoroughly tested, signals can be
sent through the processor and analyzed for correctness on the other
side (prior to output).

final comments
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most of the requirements for this project remain to be specified. this
is because much of the project is designed to be as extensible as
possible and suit the needs of any audiophile who happens to run across
it. thus, it would be nice to design the system with a plug-in
interface similar to the sort available with Photoshop or Netscape.