Credits

The backing band plays recorded instruments, and the page reader borrows one model it did not train. Somebody made each of them and gave the results away; this page says who, which is both a licence obligation and the least they are owed.

The drum kit

Kick, snare, cross-stick, hi-hat and ride come from the Versilian Community Sample Library by Versilian Studios LLC, released under CC0 1.0 — public domain. No credit is required for these. It is here anyway.

The upright bass and the piano

Sampled from FluidR3_GM by Frank Wen, by way of Benjamin Gleitzman’s pre-rendered MIDI.js soundfonts, under Creative Commons Attribution 3.0. This credit is the attribution that licence asks for.

What was done to them

The drums were mixed down to mono, trimmed to their attack, cut short with a fade and levelled. The bass and piano are sampled every few semitones and pitch-shifted in between. The room you hear them in is not a recording of anywhere — it is noise dying away, made up on the spot by your browser. The whole process is one script in the repository, so any of this can be checked or changed.

The chord symbols

When you photograph a page, the letters of its chord symbols are read by PaddleOCR’s PP-OCRv5 English text recogniser, by the PaddlePaddle authors, in the ONNX form RapidOCR publishes, under the Apache License 2.0. It runs on our own server beside the rest of the reader and is used unmodified; the licence text ships with it.

The MP3 encoder

A backing track exported as MP3 is encoded in your browser by lamejs, a JavaScript port of the LAME encoder, under the GNU Lesser General Public License 3.0. It is used unmodified and loaded as its own separate script, only when somebody asks for an MP3; its source and licence are at that link.

The app itself

Good Ears is designed and built by Chris Rouxel, and it is not open source: the software, the reader and the weights it was trained with belong to Christopher Rouxel. The chord recogniser above is PaddleOCR’s and the MP3 encoder is lamejs’s, each under its own licence. Every sound above was chosen because its licence allows that — public domain, or attribution, which this page is. See the terms and the privacy page, which is the one that matters: your microphone never leaves your device.