comparison README @ 95:dab7e7bfeba1 matthiasm-plugin 0.2

added release notes, updated README

 * Tuned Log-frequency Spectrum: has the same format as Log-frequency Spectrum, but has been processed by the following processes: tuning, subtraction of background spectrum, spectral whitening.
 * Semitone Spectrum: a spectral representation with one bin per semitone. If NNLS is selected in the parameters, this is the note activation, otherwise just a linear mapping to semitones.
 * Bass Chromagram: a 12-dimensional chromagram, restricted to the bass range. At each frame the Semitone Spectrum is multiplied by a bass pattern and then mapped to the 12 chroma bins. 
 * Chromagram: a 12-dimensional chromagram, restricted with mid-range emphasis. At each frame the Semitone Spectrum is multiplied by a mid-range pattern and then mapped to the 12 chroma bins.
 * Chromagram and Bass Chromagram: a 24-dimensional chromagram, consisting of the both Bass Chromgram and Chromagram, see above. When normalisation is used, this representation will however be scaled differently, and hence be different from the individual chromagrams.
+* Consonance estimate: A simple consonance value based on the convolution of a consonance profile with the Semitone Spectrum. Experimental status. Compare two pieces of audio in terms of consonance if the instrumentation is similar. Instruments with fluctuating pitches (also: voice) will decrease the consonance value.
 
 ### Chordino ###
 
 System identifier – vamp:nnls-chroma:chordino
 RDF URI – http://vamp-plugins.org/rdf/plugins/nnls-chroma#chordino

 * spectral roll on (0 % -- 5 %; default: 0 %): consider the cumulative energy spectrum (from low to high frequencies). All bins below the first bin whose cumulative energy exceeds the quantile [spectral roll on] x [total energy] will be set to 0. A value of 0 means that no bins will be changed.
 * tuning mode (global or local; default: global): local uses a local average for tuning. Local tuning is only advisable when the tuning is likely to change over the audio, for example in podcasts, or in a cappella singing.
 * spectral whitening (0.0 -- 1.0; default: 1.0): determines how much the log-frequency spectrum is whitened. A value of 0.0 means no whitening. For values other than 0.0 the log-freq spectral bins are divided by  [standard deviation of their neighbours]^[spectral whitening], where "^" means "to the power of".
 * spectral shape (0.5 -- 0.9; default: 0.7): the shape of the notes in the NNLS dictionary. Their harmonic amplitude follows a geometrically decreasing pattern, in which the i-th harmonic has an amplitude of [spectral shape]^[i-1], where "^" means "to the power of".
 * chroma normalisation (none, maximum norm, L1 norm, L2 norm; default: none): determines whether or how the chromagrams are normalised. If the setting is not 'none', then each chroma frame separately is divided by the chosen vector norm. Note that normalisation implies that the joint 24-dim. "Chroma and Bass Chromagram" output will be different from the individual 12-dim. "Chromagram" and "Bass Chromagram" outputs.
+* boost likelihood of the N (no chord) label (0.0 -- 1.0; default: 0.1): leads to greater values in the profile of the "no chord" chord, hence non-harmonic parts of audio files are more likely to be recogised as such. Warning: for values above the default, it quickly leads to many chords being misclassified as N.
 
 #### Outputs ####
 
 * Chord Estimate: estimated chord times and labels.
 * Harmonic Change Value: an indication of the likelihood of harmonic change. Depends on the chord dictionary. Calculation is different depending on whether the Viterbi algorithm is used for chord estimation, or the simple chord estimate.
+* Note Representation of Chord Estimate: a simple MIDI-like represenation of the estimated chord with bass note (if applicable) and chord notes. Can be used, for example, to export MIDI chords from Sonic Visuliser.
 
 ### Tuning ###
 
 System identifier – vamp:nnls-chroma:tuning
 RDF URI – http://vamp-plugins.org/rdf/plugins/nnls-chroma#tuning