Audio Engine

The core audio engine is written in safe Rust with zero-copy buffer management and lock-free ring buffer communication.

Audio Processing Graph

brūhi uses a directed acyclic graph (DAG) for signal routing and real-time mixing:

[Deck A / B] ──→ [Gap Killer & Crossfader] ──→ [Master Mix] ──→ [DSP Chain] ──→ [Encoders / Outputs]
[Microphones] ──→ [Mic DSP & HPF Filter] ─────↗

Thread & I/O Model

• Audio Thread: Real-time priority, zero allocations on hot paths, lock-free ring buffers.
• Playout & Preload Thread: Evaluates upcoming queue items, handles idle deck auto preloading based on playback state.
• Control Thread: Interfaces with Tauri IPC, UI state, and parameter changes.
• Network Encoder Thread: Handles Icecast MP3/Opus streaming, SRT/RTP packet fan-out.

Codec & Broadcast Output Support

• Opus Encoder with Ogg Support: High-efficiency streaming with native Ogg container encapsulation.
• Icecast MP3 Optimization: Enhanced connection retries, buffer management, and ICY metadata updates.
• Multi-Format Fan-out: Simultaneous output to MP3, Opus, AAC-LC, WAV, and FLAC without CPU overhead.

Automated Crossfading & Gap Killer

• Crossfade Visualizer: Real-time visual curve monitoring for deck transitions.
• Gap Killer Logic: Automatically detects track silence at intro/outro using configurable dB threshold settings and duration parameters.
• Deck Preloading: When the active deck nears completion, the idle deck preloads the next track seamlessly.