Audio Effect (audioeffect)
A pluggable audio effect filter chain.
Audio Frame (audioframe)
The basic unit for transferring audio data.
Audio Mixer (audiomixer)
Mixes multiple audio sources into a single output.
Audio Sink (audiosink)
Audio output abstraction supporting multiple output destinations.
Audio Source (audiosource)
Audio input abstraction supporting multiple input sources.
Effect Plugins (effect-plugins)
The XSTAR audio framework ships with 11 built-in effect plugins, all located in xstar/kernel/audio/effect-*.c. This document categorizes them as "format conversion → signal processing → special effects" with usage, JSON config, and key algorithms.
Extending Guide (extending)
This document explains how to write custom components for the XSTAR audio framework, covering three extension approaches with complete implementation templates for effect / source / sink.
Audio Framework Overview (overview)
The XSTAR audio framework is a lightweight, modular, JSON-driven embedded audio processing subsystem located at xstar/kernel/audio/. Built around the classic Source → Filter → Sink pipeline model with a pluggable effect engine and mixer, it supports a wide range of audio applications including file playback, microphone capture, mixing, spectrum analysis, and AFSK modulation/demodulation.
Usage Examples (usage-examples)
This document demonstrates common patterns of the XSTAR audio framework through 4 complete, runnable scenarios. Each example includes Goal → Data Flow → Code → Key Notes.