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Preview of Euvoli โ€” Pass Messages in Music

Euvoli โ€” Pass Messages in Music by Melora

Euvoli encodes and decodes messages passed as musical note sequences directly within Gmail and Facebook Messenger. In Gmail, users click the Encode button in the compose toolbar to convert any message into Messages hidden in plain sight.

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About this extension
EUVOLI โ€” PASS MESSAGES IN MUSIC
Euvoli brings an entirely new kind of privacy to your email and messaging. Instead of obvious encryption that signals "something secret is here," Euvoli transforms your message into a beautiful sequence of musical notes โ€” passing it in plain sight where no one would ever think to look.
โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ€จWHY EUVOLI IS DIFFERENTโ€จโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€
Every other privacy tool โ€” Signal, PGP, encrypted email โ€” has one fatal flaw: it's obvious. When someone sees an encrypted message, they know a secret exists. In repressive environments, that alone can be dangerous. Border agents, surveillance systems, and deep packet inspection tools are all trained to detect encryption.
Euvoli takes a completely different approach. Your message doesn't look encrypted โ€” it looks like music data. A JSON note sequence shared in an email or message raises no flags, triggers no algorithms, and attracts no attention. The message isn't just unreadable without the key โ€” its very existence is concealed.
This is steganography: concealing the fact that a message exists, not just its contents.
โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ€จWHAT EUVOLI DOESโ€จโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€
Euvoli encodes any text message as a sequence of musical note pairs using the Melography protocol โ€” a cryptographic system where each character maps to a unique pair of musical notes through a passphrase-derived cipher.
The same letter maps to completely different notes every time it appears, making frequency analysis impossible. Without the correct passphrase, an observer cannot even locate where the message begins or ends โ€” let alone read it.
In Gmail, Euvoli adds a simple ๐ŸŽต Encode button to your compose window. Type your message, enter a shared passphrase, click Encode & Insert โ€” and your message becomes a stream of note data sitting quietly in your email. When your recipient opens the email, a ๐ŸŽต Decode Euvoli Message button appears automatically. They enter the passphrase and read your original message.
In Facebook Messenger, Euvoli adds a ๐ŸŽต button directly in the message toolbar alongside the native emoji, photo, and GIF buttons. Encode any message before sending it. Recipients see a Decode Euvoli Message option in the three-dot menu on any received Euvoli message.
โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ€จHOW IT WORKS โ€” THE MELOGRAPHY PROTOCOLโ€จโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€
Melography is a deterministic bidirectional mapping system that converts text into musical note pairs:
96 printable characters mapped to 130 unique note pairs
Each character uses TWO musical notes โ€” creating rich musical intervals
Polyalphabetic cipher: same character โ†’ different notes every time
Passphrase feeds into PBKDF2 key derivation โ†’ ChaCha20 stream cipher
Each character position gets a unique cryptographic offset
Message boundaries are concealed โ€” without the key, you cannot find where the message starts or ends
Steganographic padding before and after the message conceals its length
The note sequence sounds like real music when played back
The result is a system where:โ€จโœ“ Content is protected โ€” unreadable without the passphraseโ€จโœ“ Existence is concealed โ€” message boundaries unlocatable without the passphraseโ€จโœ“ Length is concealed โ€” padding obscures how long the message isโ€จโœ“ Frequency analysis is defeated โ€” polyalphabetic mappingโ€จโœ“ No dedicated infrastructure needed โ€” works over any platform
โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ€จFEATURESโ€จโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€
โœฆ ONE-CLICK ENCODING IN GMAILโ€จClick the ๐ŸŽต Encode button in any Gmail compose window. Type your message, enter your shared passphrase, choose to insert as text or download as a file. That's it.
โœฆ FACEBOOK MESSENGER SUPPORTโ€จA ๐ŸŽต Euvoli button sits naturally in the Messenger toolbar alongside emoji, photo, and GIF buttons. Works in both the full Messenger page and the modal chat window. Decode option appears in the three-dot menu on received Euvoli messages.
โœฆ AUTOMATIC DECODE DETECTIONโ€จWhen you receive an email containing an Euvoli note sequence, a ๐ŸŽต Decode Euvoli Message button appears automatically at the top of the email. Enter the passphrase to reveal the message instantly.
โœฆ LOCAL ENCODING โ€” YOUR MESSAGE NEVER LEAVES YOUR DEVICEโ€จAll encoding and decoding happens in your browser. Your plaintext message is never transmitted to any server. The passphrase never leaves your device. Only the encoded note sequence โ€” which is meaningless without the key โ€” is inserted into your email or message.
โœฆ PASSPHRASE PROTECTIONโ€จShare a passphrase with your recipient through any channel โ€” a phone call, in person, a previous message. Once established, all future communication using that passphrase is protected.
โœฆ TRANSPORT AGNOSTICโ€จThe encoded note sequence is just text โ€” it works over any platform that can carry text or files. Email, messaging apps, social media posts, SMS. If you can send text, you can send an Euvoli message.
โœฆ MUSICALLY AUTHENTICโ€จThe note sequences are designed to sound like real music when played back. The Euvoli web app at euvoli.qizhonglabs.com lets you hear your encoded message played on piano, strings, music box, harp, or brass.
โœฆ NO ACCOUNT REQUIREDโ€จInstall and start encoding immediately. No sign-up, no account, no personal information required.
โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ€จWHO EUVOLI IS FORโ€จโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€
JOURNALISTS AND ACTIVISTSโ€จCommunicating in environments where encryption is detected, flagged, or illegal. Euvoli messages pass through surveillance systems as ordinary data files. No Euvoli-specific traffic pattern exists to block or detect.
PRIVACY-CONSCIOUS INDIVIDUALSโ€จAnyone who wants genuine privacy without the social signal that comes with obvious encryption. Your communication looks completely ordinary.
HUMAN RIGHTS DEFENDERSโ€จOperating in regions where encrypted communication attracts unwanted attention. Euvoli provides plausible deniability โ€” the note sequence is just music data, nothing more.
BUSINESSES WITH CONFIDENTIAL COMMUNICATIONSโ€จLegal, financial, medical, or strategic communications that require discretion beyond standard email security.
CREATIVE USERSโ€จPass personal messages inside music. Send someone a melody that only they can decode. Use it as a novel form of personal expression.
โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ€จPRIVACY AND SECURITYโ€จโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€
Euvoli is built on a simple principle: we cannot read your messages even if we wanted to.
All encoding happens locally in your browser
Your message never travels over the network in plaintext
Your passphrase is never stored or transmitted
The extension only accesses mail.google.com and facebook.com to inject buttons
No message history is stored anywhere
No account or personal information is required
HTTPS enforced on all connections
Full privacy policy: https://euvoli.qizhonglabs.com/privacy
โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ€จTHE MELOGRAPHY PROTOCOLโ€จโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€
Melography is an open protocol developed by QIZHONG LABS combining cryptographic security with musical steganography. Unlike traditional encryption which conceals content, Melography conceals the existence of communication itself.
Key technical properties:
PBKDF2 key derivation with 100,000 iterations
ChaCha20 cryptographically secure stream cipher
Polyalphabetic substitution โ€” defeats frequency analysis
Chaffing and winnowing โ€” random padding conceals message boundaries
Statistical indistinguishability โ€” encoded sequences match natural music distribution
Compression immune โ€” JSON format survives audio transcoding and platform processing
Deep packet inspection resistant โ€” no Euvoli-specific traffic signature
โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ€จGETTING STARTED โ€” GMAILโ€จโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€
Install the Euvoli extension
Open Gmail and click Compose
Click the ๐ŸŽต Encode button in the toolbar
Type your message
Enter a passphrase you've shared with your recipient
Click Encode & Insert
Send your email normally
Your recipient installs Euvoli, opens the email, clicks ๐ŸŽต Decode Euvoli Message, enters the passphrase, and reads your message.
โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ€จGETTING STARTED โ€” FACEBOOK MESSENGERโ€จโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€
Install the Euvoli extension
Open Facebook Messenger
Click the ๐ŸŽต button in the message toolbar
Type your message and passphrase
Click Encode & Insert
Send your message normally
Your recipient opens the message, clicks the three-dot menu, selects Decode Euvoli Message, enters the passphrase, and reads your message.
โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ€จABOUT EUVOLIโ€จโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€
Euvoli is developed by QIZHONG LABS, a California sole proprietorship. The Melography protocol is designed to provide genuine communication privacy for journalists, activists, and privacy-conscious individuals worldwide.
Web app: https://euvoli.qizhonglabs.comโ€จPrivacy policy: https://euvoli.qizhonglabs.com/privacy
โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€
Euvoli โ€” Because privacy shouldn't look like a secret.
Developer comments
Euvoli is a Chrome/Firefox extension that encodes and
decodes secret messages as musical note sequences
(Melography protocol) directly in Gmail and Facebook
Messenger.

All encoding and decoding happens locally in the browser
using the bundled melography.js engine. No plaintext is
ever transmitted to any server.

The extension injects UI buttons into:
- mail.google.com (Gmail compose + received emails)
- www.facebook.com (Messenger compose toolbar +
three-dot message menu)

Server fallback (euvoli.qizhonglabs.com) is only called
if local encoding fails โ€” it receives encoded JSON only,
never plaintext or passphrases.

No remote code execution. All JavaScript is bundled
within the extension package. No eval() or dynamic
code execution is used.

To test:
1. Open Gmail โ†’ Compose โ†’ click ๐ŸŽต Encode button
2. Type message + passphrase โ†’ Encode & Insert
3. Send to yourself โ†’ open email โ†’ Decode button appears
4. Enter same passphrase โ†’ original message revealed

For Facebook:
1. Open facebook.com/messages
2. Open any conversation
3. Click ๐ŸŽต button in Messenger toolbar
4. Type message + passphrase โ†’ Encode & Insert
5. Received messages show ๐Ÿ”“ Decode in three-dot menu
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Permissions and data

Required permissions:

  • Access your data for mail.google.com
  • Access your data for www.facebook.com
  • Access your data for euvoli.qizhonglabs.com

Data collection:

  • The developer says this extension doesn't require data collection.
Learn more
More information
Add-on Links
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Version
2.1.1
Size
173.52 KB
Last updated
3 days ago (Aug 5, 2026)
Related Categories
  • Privacy & Security
  • Language Support
  • Social & Communication
License
MIT License
Version History
  • See all versions
Tags
  • chat
  • facebook
  • privacy
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