MIDI-Driven Visual Performance Engine
MIDISynth
A native Metal-powered visual performance engine for macOS and iOS.
MIDI-triggered video, generative visuals, real-time audio analysis,
and H.265 with transparency — built for the stage.
Overview
Your music becomes the visual.
MIDISynth turns MIDI signals and live audio into stunning real-time visuals. Trigger videos, images, geometric shapes, and GPU-powered shader effects directly from your instruments — with frame-accurate timing and zero compromise on latency.
There is no comparable native app for Mac that combines MIDI-triggered media playback with Metal GPU rendering, H.265 transparency, real-time FFT audio analysis, and generative visuals — all in a single, efficient package. MIDISynth fills a gap that professional visual performers have been waiting for.
MIDI Engine
Every note triggers a visual.
MIDISynth uses CoreMIDI for hardware-level MIDI input with sub-10ms latency. Map any note on any channel to any visual effect — from a simple video trigger to a complex layered shader composition. Your drummer's kick pad, your guitarist's footswitch, or a full MIDI controller — everything becomes a visual trigger.
16 MIDI Channels
Full 0–127 note range with velocity sensitivity. Each note can trigger a different visual effect with velocity-controlled intensity.
MIDI Learn
One-click learn mode captures incoming channel + note combinations. No manual configuration needed — just play and assign.
MIDI Clock Sync
Real-time BPM detection from MIDI Clock (24 PPQN) with adaptive estimation. Visuals lock to your tempo automatically.
3 Retrigger Modes
Restart, Ignore While Active, or Stack — control how repeated triggers behave for each mapped effect independently.
Beat Retrigger
Auto-synthesize trigger events on detected beats with configurable minimum interval guard (0.05–5 seconds).
Any Device Source
Wildcard device matching lets you swap MIDI controllers freely. No re-mapping needed when changing hardware.
Visual Engine
Metal-powered. Frame-accurate. Beautiful.
The rendering engine is built entirely on Apple's Metal framework with triple-buffered frame pipelining and CVDisplayLink synchronization. Every visual runs at a locked 60 FPS with GPU-accelerated compositing — from simple image overlays to complex generative particle systems.
Video & Media Playback
- H.265 (HEVC) with alpha transparency — perfect for overlays and stage content
- H.264 and ProRes 422 support for production-grade workflows
- Continuous playback (0.05×–4× speed) or MIDI-triggered frame-step mode
- CVMetalTextureCache for zero-copy GPU texture binding
- Per-effect independent playback contexts — multiple simultaneous videos
GPU Shader Effects
- Radial Pulse — expanding/contracting radial waves
- Organic Noise — Perlin-like flow-field patterns
- Wave Distortion — sinusoidal interference patterns
- Flash Gradient — pulsing color gradients
- Particle Field — GPU-driven particle systems
- Electrocardiogram — waveform trace visualization
- Arabesque Rings — concentric morphing ring patterns
- Organic Dot Morph — blob/cell-like morphing shapes
- Custom — load your own Metal shaders
16 Geometric Shapes
Generative Visual Engine
- Algorithmic entity spawning driven by MIDI pitch, velocity, and audio features
- 5 motion characters: Organic, Flowing, Nervous, Static, Cosmic
- Procedural ribbon trails with velocity-dependent generation
- Instanced rendering for hundreds of simultaneous entities
- Palette-driven coloring with smooth interpolation
Layering & Compositing
- Multiple independent render layers with per-layer blend modes
- Blend modes: Normal, Additive, Multiply, Screen
- Per-layer opacity, visibility, and ordering control
- Trigger variation: random position, scale, rotation, and color per event
Supported Formats
Video
Image
Recording
Audio Analysis
Your sound shapes the visuals.
MIDISynth listens to your live audio through any connected input — built-in mic, USB audio interface, line-in — and transforms it into real-time visual modulation. Your guitar riff changes the colors. Your bass line drives the scale. The kick drum pulses the intensity. All at 25 Hz analysis rate with zero perceptible delay.
4096-Point FFT
Hann-windowed spectral analysis using Apple's Accelerate framework (vDSP). ~93ms analysis window at 44.1 kHz with ~10.8 Hz frequency resolution.
6 Spectral Bands
Sub-Bass (20–60 Hz), Bass (60–250 Hz), Low Mid (250–500 Hz), Mid (500–2 kHz), High Mid (2–4 kHz), High (4–20 kHz). Each band drives visual parameters independently.
Beat Detection
Spectral flux-based onset detection with adaptive threshold. Real-time BPM estimation from inter-onset intervals, clamped 60–200 BPM.
8 Modulation Presets
Kick Pulse, Bass Groove, Vocal Sparkle, High Shimmer, Loudness Glow, Full Mix, Beat Trigger, and Off. One-click audio-reactive visuals.
Modulation Sources
Performance & Architecture
Built for the stage. Engineered for speed.
MIDISynth is 100% native Apple — Metal rendering, CoreMIDI, Accelerate FFT, AVFoundation. No Electron wrappers. No cross-platform compromises. Just raw performance on Apple silicon.
60fps
Locked Frame Rate
Triple-buffered Metal rendering with CVDisplayLink/CADisplayLink synchronization. Jitter-free visuals.
<10ms
MIDI Latency
CoreMIDI hardware-level input. From drum trigger to visual output in under one frame.
180
Swift Source Files
A serious codebase: SwiftUI, Metal, Combine, CoreMIDI, AVFoundation, Accelerate.
4
Metal Shader Files
800+ lines of custom GPU code: shapes, effects, generative entities, and ribbon trails.
Triple-Buffer Pipeline
3 in-flight frame buffers with semaphore gating prevent GPU/CPU synchronization stalls under any load.
Lock-Free Audio
Atomic frame mirroring from the DSP queue to the render thread. No mutexes, no blocking, no dropped frames.
HDMI Output
Dual-window architecture on iPad: content on device, fullscreen visuals on external HDMI display for projectors and TVs.
Video Recording
Record your visual performance in H.264, H.265, or ProRes 422 — up to 4K resolution — directly from the Metal render pipeline.
Scene Presets
Save and load complete effect configurations, shader presets, and generative profiles. Switch entire visual setups instantly.
Performance Scaling
Safe mode, output scale (0.25×–1×), master brightness (up to 1.5× for projection), and global opacity for fine-tuned performance.
Platforms
Native on Mac and iPad
MIDISynth runs natively on macOS and iOS — optimized for Apple silicon and Metal GPU rendering. Use your MacBook Pro as the main performance rig, or plug an iPad into a projector via HDMI for a lightweight portable setup.
macOS 14.6+
Full-featured visual performance engine with multi-display support and all MIDI/audio capabilities
iOS 17.6+
Portable stage setup with HDMI output — plug iPad into any projector or TV for instant visuals
Experience
Born on stage. Built from 25 years on professional film sets.
Use Cases
From rehearsal room to main stage
MIDISynth is designed for anyone who wants to create real-time visuals driven by music — whether you're a solo performer, a band, a VJ, or a visual artist.
Live Band Performances
Drum triggers, guitar audio, bass lines — every instrument drives visuals in real-time via MIDI and audio analysis. Beat-accurate. No VJ operator needed.
VJ & Visual Performance
Trigger video clips, shader effects, and generative visuals from a MIDI controller. Layer, blend, and composite live on stage.
Theater & Stage Shows
Synchronized visual backdrops, H.265 transparent overlays, and precisely timed MIDI-triggered scene changes for theatrical productions.
Art Installations
Generative visuals driven by audio input. Microphone-reactive environments that respond to ambient sound, visitors, and live performances.
Worship & Events
Create immersive visual environments for worship services, conferences, and events — synchronized to live music without a dedicated video operator.
Film & Music Video Production
Real-time visual content generation for music videos, background plates, and on-set screen content. Record directly from the render pipeline in ProRes or H.265.
Contact
Let's talk
Interested in MIDISynth?
Whether you're looking for a visual performance solution for your band, exploring licensing or acquisition opportunities, or want to see a live demo — we'd love to hear from you.