BLAST: Bash-Like Audio Scripting Tool

This project aims to facilitate real-time algorithmic audio in Rust. It features a Bash-like scripting language that is interpreted by a REPL.

Dependencies

One of the goals of this project is to realize as many features as possible with as few dependencies as possible. It currently only uses the alsa-sys and libc crates for interaction with OS audio and terminal internals.

Modules

src/main.rs:

• executes audio parsing library functions through extension matching
• catches unsupported audio formats

src/lib.rs:

• exposes modules to main.rs and hosts testing

src/audio_processing

• pre-parses all audio files in the assets/ folder
• configures ALSA according to a consensus based on the audio files' properties (namely sample rate and number of channels)
• interacts directly with hardware and the DMA buffer for low-latency writes
• processes Commands separately from audio thread for string parsing, hashmap operations, and robust error-handling
• uses terminal in raw mode for custom terminal rendering
• implements fast RNG with xoroshiro128+ generation, Lemire's fast modulo, and architecture-specific seeding

src/file_parsing:

• mpeg
  • parses MPEG frames
  • TODO: implement actual decoding of compressed data
• wav
  • parses RIFF, fmt, and data chunks sequentially
• aiff
  • parses FORM, COMM, and SSND chunks sequentially
• decode_helpers
  • implements custom DecodeErrors and DecodeResult for in-memory file parsing
  • provides AudioFile struct to return necessary data for audio APIs

Documents consulted

Audio specs:

• DataVoyage's informal MPEG overview
• Original AIFF-1.3 specification
• McGill on WAVE