BEAST - Project Architecture
Tim Janik Stefan Westerfeld
Document revised: Sun Jul 09 12:58:38 2006
This document provides an architectural overview of the BEAST audio synthesis package and related components.

Table of Contents
1 · Programs and Libraries
2 · Components
3 · Samples and Wave Files
3.1 · Extra Information (XInfo Strings) for Wave Files
3.1.1 · Wave Chunk specific XInfos
3.1.2 · Wave specific XInfos
3.1.3 · Wave Library specific XInfos

1 Programs and Libraries

SFIDL - The IDL compiler (sfidl(1)) used for language bindings and plugins
BseWaveTool - A small program to generate multi-sample .BSEWAVE files
BEAST - a Gtk+ based GUI front-end (beast(1)) for BSE
GXK - a library containing extensions to Gtk+, such as XML-parser for widget templates or an action administration system
BSESCM - a Guile based scheme shell (bsescm(1)) for BSE
BSE - synthesis and sequencing library
SFI - Interface library, consisting of:
- a value abstractiong SfiValue (based on GValue)
- a serializable parameter abstraction based on GParamSpec
- a threading abstraction SfiThread (based on GThread)
- primitive type implementations (record, sequenzes, rings)
- a glue layer to allow function calls and signals across process boundaries
- a simple communication layer based on SfiValue for process boundaries
- basic serialization mechanisms to allow implementations of persistent object storage
- miscellaneous utilities.
GLib-Extra - utility functions which are subject to be folded back into GLib at some point.

2 Components

BSESCM - a Guile based scheme shell (bsescm(1)) for BSE used for scripting BEAST and to run standalone scripts
BEAST - a Gtk+ based GUI front-end (beast(1)) for BSE
BSE - the sequencing and synthesis core, consisting of:
- Plugin interface
- MIDI Event processing logic
- MIDI File import
- Undo/redo stack
- Object framework
- Glue layer + scripting objects
- Song, track, part, mixer and wave objects
- Synthesis networks
- Sequencer (seperately threaded)
- Synthesis Engine (seperately threaded)
- Input output drivers for PCM and MIDI
- OSS MIDI and PCM driver
- Standard synthesis modules

3 Samples and Wave Files

Sample Data is organized at three levels:

Wave Chunks - a chunk contains one sample
Waves - multiple chunks can be put into a wave; this allows storing different samples which should be played for different notes
Wave Libraries - multiple waves can be put into a wave library

3.1 Extra Information (XInfo Strings) for Wave Files

XInfos consist of a list of "key=value" pairs. Values need to be valid UTF-8 strings, while keys may consist only of the lowercase letters 'a'-'z', the digits '0'-'9' and a dash '-'.

3.1.1 Wave Chunk specific XInfos

osc-freq - Note frequency (oscillator frequency) the chunk should be played back at. In other words, the note that was played when the chunk was recorded.
loop-type - The loop type needs to be set to indicate that the sample should be looped. Possible values are:
1. "none" - no loop
2. "jump" - plays from loop start to loop end, then jumps back to loop start
3. "ping-pong" - plays from loop start to loop end and then backwards from loop end to loop start
loop-start - The offset in samples for the start of the loop.
loop-end - The offset in samples for the end of the loop.
loop-count - A maximum limit for how often the loop should be repeated.
gus-patch-envelope - Contains the envelope points for a GUS Patch envelope.

3.1.2 Wave specific XInfos

authors - A list of the authors who participated in creating the wave file.
license - The license specifiing redistribution and other legal terms for the wave file.
blurb - A descriptive text for the wave file.
play-type - Indicates the set of required play back facilities for a wave. Supported values are:
1. wave-mono - for mono wave files,
2. gus-patch - for GUS Patches (which need a special envelope).

3.1.3 Wave Library specific XInfos

There are currently no XInfos defined for Wave Libraries, because Wave Libraries are not yet supported.


	BEAST - Project Architecture Tim Janik Stefan Westerfeld Document revised: Sun Jul 09 12:58:38 2006 This document provides an architectural overview of the BEAST audio synthesis package and related components. Table of Contents Table of Contents 1 · Programs and Libraries 2 · Components 3 · Samples and Wave Files 3.1 · Extra Information (XInfo Strings) for Wave Files 3.1.1 · Wave Chunk specific XInfos 3.1.2 · Wave specific XInfos 3.1.3 · Wave Library specific XInfos 1 Programs and Libraries SFIDL - The IDL compiler (sfidl(1)) used for language bindings and plugins BseWaveTool - A small program to generate multi-sample .BSEWAVE files BEAST - a Gtk+ based GUI front-end (beast(1)) for BSE GXK - a library containing extensions to Gtk+, such as XML-parser for widget templates or an action administration system BSESCM - a Guile based scheme shell (bsescm(1)) for BSE BSE - synthesis and sequencing library SFI - Interface library, consisting of: a value abstractiong SfiValue (based on GValue) a serializable parameter abstraction based on GParamSpec a threading abstraction SfiThread (based on GThread) primitive type implementations (record, sequenzes, rings) a glue layer to allow function calls and signals across process boundaries a simple communication layer based on SfiValue for process boundaries basic serialization mechanisms to allow implementations of persistent object storage miscellaneous utilities. GLib-Extra - utility functions which are subject to be folded back into GLib at some point. 2 Components BSESCM - a Guile based scheme shell (bsescm(1)) for BSE used for scripting BEAST and to run standalone scripts BEAST - a Gtk+ based GUI front-end (beast(1)) for BSE BSE - the sequencing and synthesis core, consisting of: Plugin interface MIDI Event processing logic MIDI File import Undo/redo stack Object framework Glue layer + scripting objects Song, track, part, mixer and wave objects Synthesis networks Sequencer (seperately threaded) Synthesis Engine (seperately threaded) Input output drivers for PCM and MIDI OSS MIDI and PCM driver Standard synthesis modules 3 Samples and Wave Files Sample Data is organized at three levels: Wave Chunks - a chunk contains one sample Waves - multiple chunks can be put into a wave; this allows storing different samples which should be played for different notes Wave Libraries - multiple waves can be put into a wave library 3.1 Extra Information (XInfo Strings) for Wave Files XInfos consist of a list of "key=value" pairs. Values need to be valid UTF-8 strings, while keys may consist only of the lowercase letters 'a'-'z', the digits '0'-'9' and a dash '-'. 3.1.1 Wave Chunk specific XInfos osc-freq - Note frequency (oscillator frequency) the chunk should be played back at. In other words, the note that was played when the chunk was recorded. loop-type - The loop type needs to be set to indicate that the sample should be looped. Possible values are: "none" - no loop "jump" - plays from loop start to loop end, then jumps back to loop start "ping-pong" - plays from loop start to loop end and then backwards from loop end to loop start loop-start - The offset in samples for the start of the loop. loop-end - The offset in samples for the end of the loop. loop-count - A maximum limit for how often the loop should be repeated. gus-patch-envelope - Contains the envelope points for a GUS Patch envelope. 3.1.2 Wave specific XInfos authors - A list of the authors who participated in creating the wave file. license - The license specifiing redistribution and other legal terms for the wave file. blurb - A descriptive text for the wave file. play-type - Indicates the set of required play back facilities for a wave. Supported values are: wave-mono - for mono wave files, gus-patch - for GUS Patches (which need a special envelope). 3.1.3 Wave Library specific XInfos There are currently no XInfos defined for Wave Libraries, because Wave Libraries are not yet supported.