Spectral: Hidden in Sound

Spectral turns images into sound — and back again.

Every photo has a unique acoustic fingerprint. Spectral encodes it into audio, transmits it through the air or as a file, and decodes it back into the original image on another device.

MODES • Send — encode any image or message into audio • Receive — decode incoming audio back into an image or text • Listen — record any sound and watch it become a spectrogram in real time • Sonify — hear what your image sounds like • Archive — your full transmission history

HOW IT WORKS Play the encoded audio on one phone. Hold another phone's mic close. The image or message transfers — no internet, no Bluetooth, no connection of any kind. Purely acoustic.

Or share the WAV file directly for a lossless digital transfer.

ENCRYPTED MESSAGES Add a passphrase to your text transmissions. Only someone with the passphrase can decode it.

FULLY OFFLINE Spectral works entirely on your device. No servers. No accounts. No tracking. Nothing ever leaves your phone.

15 free transmissions included. Unlock unlimited use for a one-time purchase — no subscription, ever.