Colophon

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Overview

Colophon reads and writes the tags of MP3 files: title, artist, album, track and disc numbers, year, genre, comment and cover art. Open a folder or a few files, browse them by album, artist or folder, edit one track or a whole album at once, and save when you are ready: nothing touches your files before that.

It reads and writes ID3v2.2, ID3v2.3, ID3v2.4, ID3v1.0 and ID3v1.1, and reads APE tags, which it leaves as they are.

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Features

• Library: open folders and files, or drop them on the window. The sidebar lists the folders, albums and artists, every track, the recently changed ones and the files that could not be read.
• Table: sort by any column, filter by title, artist or album, and show, hide, resize and reorder the columns.
• Editing: in the inspector or right in the table, one track or many at once, where values the tracks do not share say so. Number the tracks of an album in one go, select a whole album, undo and redo every change.
• Cover art: replace it with an image picked or dropped on the window, extract it to a file, or remove it.
• Saving: changes wait, marked track by track, until you save them, and quitting asks what to do with them.
• Warnings: a track without a number in a numbered album, an album artist unlike the rest of its album, a value an ID3v1 tag cannot hold whole.
• Tag versions: write ID3v2.4 or ID3v2.3 by default, and keep, always write or never write ID3v1. Developer mode chooses the versions file by file and shows every frame, with the text encoding, padding and unsynchronisation of what is saved.
• Player: listen to a track before tagging it, and seek in its waveform.
• Command palette: every command by name, with Ctrl+K (⌘+K on macOS), and the keyboard shortcuts of each platform.
• Light and dark themes, following the system, in English and French.

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Install

Download the latest version from the releases page:

Platform	File
macOS, Apple silicon and Intel	Colophon-<version>.dmg
Windows 10 and 11, x64	Colophon-<version>-setup.exe
Linux, x86_64	Colophon-<version>-x86_64.AppImage

macOS: open the disk image and drag Colophon to Applications. The app is not signed with an Apple Developer ID, so the first time macOS says it could not verify Colophon and only offers Done or Move to Trash: click Done, then either

• go to System Settings → Privacy & Security, scroll down to Security, click Open Anyway next to the line about Colophon (it shows for about an hour after the attempt), confirm with your password or Touch ID, and open Colophon again;

• or lift the quarantine macOS put on the downloaded app, from the Terminal:

  xattr -dr com.apple.quarantine /Applications/Colophon.app
  

Either way, macOS remembers it, and Colophon then opens like any other app.

Windows: run the installer. SmartScreen may warn about an unknown publisher: click More info, then Run anyway.

Linux: make the AppImage executable, then run it:

chmod +x Colophon-*-x86_64.AppImage
./Colophon-*-x86_64.AppImage

Some distributions need FUSE 2 for AppImages (libfuse2 on Debian and Ubuntu).

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Development

Prerequisites

• Rust 1.99, which rustup installs from rust-toolchain.toml

• On Linux, the libraries of Slint and ALSA:

  sudo apt-get install libfontconfig-dev libxcb-shape0-dev libxcb-xfixes0-dev libxkbcommon-dev libasound2-dev
  

Run and test

cargo run -p colophon                                   # Build and start the app
cargo test --workspace                                  # Every test, the interface's captures included
cargo clippy --workspace --all-targets -- -D warnings   # What the CI lints
cargo fmt

The interface tests compare the window with the captures of crates/ui-slint/tests/references: after a change of the interface, UPDATE_REFERENCES=1 cargo test -p colophon-ui writes them again. The screenshots above come from cargo test -p colophon-ui --test screenshots -- --ignored.

Layout

Folder	What it holds
apps/colophon	The application: the window, the system's dialogs, and what macOS needs
crates/ui-slint	The interface, in Slint, its French translation, and its bridge to the engine
crates/engine	The application state and every command: selection, edits, undo, sorting, preferences
crates/library	Finding the audio files of a folder, reading and saving them
crates/tags	Reading and writing ID3v2, ID3v1 and APE tags
crates/player	Playing tracks and drawing their waveform

Third-party licenses

The About dialog lists the licenses of every crate Colophon ships, from crates/ui-slint/licenses/third-party.json. After a change of dependencies, cargo-about writes it again, which the CI checks:

cargo about generate -m apps/colophon/Cargo.toml --frozen about.hbs -o crates/ui-slint/licenses/third-party.json

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License

MIT. Colophon ships open-source fonts, icons and crates under their own licenses, listed in its About dialog.