ConcertCam 🎸

A minimal iOS camera app for recording concerts without Apple's audio processing — no auto-gain pumping, no limiter squash, no "muffled the second the band starts" audio. Built for iOS 26 / iPhone 17e, targeting iOS 18+.

Why

The stock Camera app runs mic input through a processing chain (automatic gain control, limiting, EQ, audio zoom beamforming) that crushes loud music. Third-party apps can opt out. ConcertCam gives you three audio modes, from "stock minus the worst of it" to "completely unprocessed."

Audio modes

Mode	What it is	When to use
Stereo	Stereo capture with audio zoom OFF and wind removal OFF (💨 button can re-enable wind removal)	Default; keeps stereo width with minimal processing
Raw	Mono through an AVAudioSession in .measurement mode — bypasses AGC/limiter/EQ entirely. Pick the physical mic (Bottom / Front / Back); a cardioid pickup pattern is requested automatically when the hardware supports it	Very loud shows; maximum dynamic range and fidelity
AudioZoom	Stereo with audio zoom + wind removal deliberately ON — the pickup beam narrows with your video zoom	Emergency suppression of loudly singing neighbors

Raw + Back mic + cardioid = pickup aimed at the stage with the phone body shadowing the crowd, and zero DSP on the music.

Camera features

• Night mode (🌙) — low-light auto frame rate (30 → 24 fps for longer exposure), the same mechanism the stock camera uses for low-light video. Available on 30 fps formats
• Tap to focus/expose with stock-style indicator box
• Zoom presets built from the device's real lens switch-over points, plus pinch-to-zoom (works mid-recording)
• Resolution/fps picker — 1080p/4K at 30/60, filtered to device support; persisted
• Stabilization picker — Off / Standard / Cinematic / Extended (stronger = steadier but more crop; pick mode before framing)
• Pause/resume during recording — stitches into a single file
• Live mic level meter — computed from the actual recording sample buffers; doubles as a covered-mic-port and clipping indicator
• Horizon level — CoreMotion line that snaps yellow when level, in portrait and landscape grips
• "Rotate for YouTube" reminder — turns red if you're actually recording in portrait
• Portrait-locked UI with controls that rotate in place (no preview snap on rotation); recordings still orient correctly via RotationCoordinator
• Recordings save straight to Photos

Building

brew install xcodegen
xcodegen generate
open ConcertCam.xcodeproj

In Xcode: select the ConcertCam target → Signing & Capabilities → choose your team, then run on a device (camera apps are useless in the Simulator). With a free Apple ID the install expires after 7 days — re-run from Xcode the day before the show.

Notable API facts (verified against the iOS 26.5 SDK)

• AVCaptureDeviceInput.isAudioZoomEnabled is iOS 26.4+, and audio zoom only applies when multichannelAudioMode != .none — third-party apps sidestep it by default
• Stock camera users can disable audio zoom at Settings → Camera → Record Sound → Audio Zoom (iOS 26.4+; grayed out in Mono format)
• AVCaptureAudioChannel.averagePowerLevel never updates on iOS — meter from an AVCaptureAudioDataOutput instead
• Wind-noise removal (isWindNoiseRemovalEnabled) also requires the multichannel path, so it's unavailable in Raw mode by design