BRIR Spatializer

Real-time BRIR (Binaural Room Impulse Response) spatializer for Windows (WPF/.NET 8). This repo focuses on low-latency convolution, AB slot switching, and device drift compensation. Audio assets are excluded from the repo.

Features

• Dual-slot BRIR processing with AB crossfade and bypass
• BRIR set interpolation for seat-grid selection
• Metering and spectrum visualization
• WASAPI shared IO with drift compensation (ASRC or slip)
• Preset save/load (JSON)

Requirements

• Windows 10/11
• .NET 8 SDK (x64)
• Optional: Python 3.10+ for BRIR generation

Quick start (app)

1. Build the solution:

dotnet build .\BrirSpatializer.sln

2. Run the app:

dotnet run --project .\BrirSpatializer.App\BrirSpatializer.App.csproj

3. In the app:

• Select an input device and an output device
• Click Start
• Load a BRIR file (or a BRIR set) for Slot A or Slot B

Tip: If you want to process system audio, route it into a virtual audio cable and select that cable as the input device.

BRIR format

Load 4-channel WAV files with channel order:

• ch0: IR_LL
• ch1: IR_LR
• ch2: IR_RL
• ch3: IR_RR

BRIR generation (optional)

The generator script uses pyroomacoustics and SOFA HRIR data. Provide --sofa-path or set SOFA_PATH.

Profiles:

• layout_7_1_4: 7.1.4 layout (L/C/R/SL/SR/BL/BR + 4 heights + LFE)
• layout_lr_sub: L/R/Sub layout
• array_main_delay: main/outfill plus delay arrays

Setup:

python -m venv .venv
.\.venv\Scripts\Activate.ps1
pip install -r .\requirements.txt

Generate:

python .\Scripts\generate_brir.py --profile layout_7_1_4 --sofa-path "C:\path\to\D1_48K_24bit_256tap_FIR_SOFA.sofa"

Outputs are written under Generated\BRIR\<profile>\ by default (ignored by git), with:

• speakers for per-speaker BRIRs
• grid_<rows>x<cols> for seat-grid BRIRs

Troubleshooting

• No audio output: confirm input/output devices are selected and sample rates match.
• Only stereo devices are supported.
• If BRIR loading fails, confirm the WAV has 4 channels in the required order.