Chris@19: 
Chris@60: Tuning Difference Plugin
Chris@60: ========================
Chris@19: 
Chris@65: ### A Vamp plugin to calculate comparative tunings of audio recordings
Chris@60: 
Chris@60:  * Home page and downloads: https://code.soundsoftware.ac.uk/projects/tuning-difference
Chris@60:  * Linux and macOS CI build: [![Build Status](https://travis-ci.org/cannam/tuning-difference.svg?branch=master)](https://travis-ci.org/cannam/tuning-difference)
Chris@68:  * Windows CI build: [![Build status](https://ci.appveyor.com/api/projects/status/62xidu404phrkw05?svg=true)](https://ci.appveyor.com/project/cannam/tuning-difference)
Chris@60: 
Chris@60: This [Vamp plugin](http://vamp-plugins.org/) estimates the tuning
Chris@60: frequency ("concert-A") of one or more recordings, by comparing
Chris@60: against with a "reference" recording of the same music that has a
Chris@60: known tuning frequency. It was designed for the purpose of identifying
Chris@60: the tuning frequency of an unknown recording in difficult cases, such
Chris@60: as where A is tuned more than a semitone below 440Hz.
Chris@21: 
Chris@58: The reference could be another performance made at a known tuning
Chris@58: frequency or, for example, an audio rendering from MIDI at A=440Hz.
Chris@21: 
Chris@58: For the plugin to establish the tuning frequency correctly, the two
Chris@58: recordings must be in the same key. Alternatively, you can use this
Chris@58: plugin to estimate the pitch difference between two recordings played
Chris@58: in different keys - where the result will consist of the difference
Chris@58: attributable to key plus any difference in tuning.
Chris@58: 
Chris@58: The plugin expects to receive two or more different recordings of the
Chris@58: same piece of music as its channels of input; the first channel will
Chris@58: be taken as the reference, and the remaining channels will be
Chris@58: individually compared against it. (You can provide this channel layout
Chris@60: using the `--multiplex` option in Sonic Annotator, for example.)  If
Chris@60: you feed it a single piece of music, you won't get anything
Chris@60: worthwhile.
Chris@21: 
Chris@60: ### Example
Chris@23: 
Chris@60: Example usage from the command line using [Sonic
Chris@60: Annotator](https://vamp-plugins.org/sonic-annotator/):
Chris@60: 
Chris@60: ```
Chris@24: $ export VAMP_PATH=.  # if running from the build directory
Chris@24: 
Chris@23: $ sonic-annotator -m -d vamp:tuning-difference:tuning-difference:tuningfreq PreludeInCMajorBWV846.mp3 BWV846Egarr.mp3 -w csv --csv-stdout --csv-omit-filename
Chris@60: ```
Chris@23: 
Chris@23: Here the first file is a MIDI rendering using a piano sample at 440Hz,
Chris@23: and the second is a harpsichord recording tuned with A=397Hz. After
Chris@23: processing, this prints
Chris@23: 
Chris@60: ```
Chris@23: 0.000000000,397.009
Chris@60: ```
Chris@23: 
Chris@60: ### Author and licence
Chris@23: 
Chris@60: Written by Chris Cannam at the Centre for Digital Music, Queen Mary
Chris@60: University of London. Copyright 2015-2019 QMUL. Published under the
Chris@60: GPL v2, see the file COPYING for details.
Chris@60: