VB-Engine

Vibe Based Engine (VBE) is a sound engine made from the ground up, written in C++(20). It is designed to take MIDI inputs and output high-quality audio as a variety of instruments (Only Acoustic Grand Piano is currently implemented, but more instruments are planned).

This program was made with the intention of implementation within my other project found here: https://github.com/l3afyb0y/Piano-Midi-Player

I have decided to release this engine to the public for use and modifications from others so that, if they find the engine's outputs to be of a higher quality than those they have access to, or find online, they may use them indiscriminately. This means the program was both designed to be built into my "MIDI player", but also attempts to be a plugin of sorts for other applications.

If you'd like compatibility with another program, please let us know in the discussions page and we can try to work on it if compaibility is possible. If there is an instrument you'd like to see in this program, please reach out there as well.

This project is a WIP until v1 release, when it will offically be considered stable and, in some sense, complete; however this doesn't mean it won't be subject to changes in the future.

Please enjoy this engine and it's features/ability. The point of this being FOSS is to help allow anyone to get into music, as I am a firm believer music (and art), and software should always be free and accessible. To that end, in order to make that possible, we must all contribute to it's accesibility. This is my attempt at a contribution to such.

Primary target is Arch Linux, with generic Linux installation support and architecture boundaries prepared for macOS/Windows wrappers.

Build

cmake --preset debug
cmake --build --preset debug
ctest --preset debug

Generate Instrument Samples

Prepare a redistributable sampled library (recommended):

bash scripts/fetch-piano-assets.sh salamander

bash scripts/generate-samples.sh

Generated public showcase audio is stored in Samples/.

Override the library path:

VB_PIANO_SFZ_PATH=/absolute/path/to/library.sfz bash scripts/generate-samples.sh

Notes:

• The core engine now requires an explicit piano_sfz_path if you want sampled playback from host code.
• The sample generator and live tester still fall back to Samples/Piano-Library/default.sfz when present.
• Current loader supports SFZ regions referencing WAV/AIFF/FLAC samples.
• Render backend selection is exposed via C API:
  • VB_PIANO_RENDER_BACKEND_AUTO
  • VB_PIANO_RENDER_BACKEND_CPU_HYBRID
  • VB_PIANO_RENDER_BACKEND_GPU_FEM (falls back safely if unavailable)
• Demo showcase generation now includes slight deterministic micro-timing/velocity humanization to reduce rigid quantized feel.

Live Piano Tester

Build and run the standalone click-to-play tester:

cmake --preset release
cmake --build --preset release --target vb_engine_piano_tester
./build/release/vb_engine_piano_tester

Quick launcher:

scripts/run-piano-tester.sh

Features:

• key range A2-C5
• pedal indicator/control in top bar (gray off, green on)
• ALSA MIDI input selection via top-bar dropdown (PORT n)
• async startup (window opens immediately while engine/sample library initializes)

Desktop entry (for local launcher integration):

• Samples/VB-Engine-Piano-Tester.desktop

Realtime defaults for stability:

• sample rate: 48000
• audio buffer: 512
• max voices: 96

Optional overrides:

VB_TESTER_SAMPLE_RATE=96000 VB_TESTER_BUFFER=1024 VB_TESTER_MAX_VOICES=80 scripts/run-piano-tester.sh

WAV health gate (peak/clipping/DC/jump checks):

bash scripts/check-wav-health.sh

Capture a new comparison baseline:

bash scripts/capture-audio-baseline.sh /tmp/vb_engine_baseline_samples

Audio-diff quality gate against baseline:

./scripts/check-audio-quality.sh /tmp/vb_engine_baseline_samples

Run full verification (tests + sanitizers + perf + sample health):

bash scripts/run-full-verification.sh

Install

Arch Linux (one-and-done)

bash scripts/install-arch.sh

Generic Linux (one-and-done)

bash scripts/install-linux.sh

Packaging

• PKGBUILD: repository-source install package

Documentation

• Docs index: docs/README.md
• Architecture: docs/architecture.md
• App integration guide: docs/developer-app-integration.md
• Licensing/compliance guide: docs/licensing-compliance.md
• Current known limits and improvement targets: docs/limitations.md
• Compatibility matrix: docs/compatibility-matrix.md
• Piano acoustics + replication doc: docs/instruments/piano-acoustics-and-implementation.md
• Sampled piano implementation doc: docs/instruments/piano-sampled-engine-implementation.md
• Instrument implementation standard: docs/instrument-implementation-standard.md
• Packaging/install behavior: docs/packaging-install.md

Status

This is an iterative foundation intended for rapid integration into Piano Player first, then expansion toward plugin wrappers (CLAP/VST3/LV2/AU/AAX by tier).