comparison toolboxes/MIRtoolbox1.3.2/MIRToolboxDemos/demo7tonality.m @ 0:e9a9cd732c1e tip

first hg version after svn

+function demo7tonality
+%To get familiar with some approaches of tonal analysis using MIRtoolbox, 
+% and to assess their performances.  
+
+% Part 1. We will first investigate the performance of the chromagram
+% analysis, using very simple musical samples. 
+
+% 1.3. In the audio file ÔtrumpetÕ, the same pitch is played by a trumpet.
+% Compute its chromagram. What are the chromas detected by the function? 
+% Can you explain the result?
+mirchromagram('trumpet')
+
+% 1.4. A more detailed representation of the chromagram can be obtained by 
+% decomposing each pitch class into its different possible absolute values. 
+% For that purpose, just add the parameter: 
+c = mirchromagram('trumpet','Wrap',0) 
+
+% 1.5. Compute also the key strength related to the chromagram. 
+mirkeystrength(c) 
+
+pause, close all
+
+% 1.6. In the audio file ÔpianoF4Õ, the same pitch is  played by a piano.
+[ks c] = mirkeystrength('pianoF4') 
+
+a = miraudio('pianoF4','excerpt',.7,2);
+[ks c] = mirkeystrength(a)
+
+pause, close all
+
+% 1.7. Investigate the chromagram analysis of triad chords
+[ks c] = mirkeystrength('Amin3')
+p = mirpeaks(ks)
+mirkey(p)
+
+pause, close all
+
+[k kc ks] = mirkey('Amaj3')
+[k kc ks] = mirkey('Amin4')
+[k kc ks] = mirkey('Amaj4')
+
+pause, close all
+
+[k kc ks] = mirkey('Amin5')
+[k kc ks] = mirkey('Amaj5')
+[k kc ks] = mirkey('Cmaj')
+
+pause, close all
+
+[k kc ks] = mirkey(miraudio('Amin3','Excerpt',.2,1))
+[k kc ks] = mirkey(miraudio('Amin4','Excerpt',.2,1))
+[k kc ks] = mirkey(miraudio('Amaj3','Excerpt',.2,1))
+[k kc ks] = mirkey(miraudio('Amaj4','Excerpt',.2,1))
+
+pause, close all
+
+[k kc ks] = mirkey(miraudio('Amin5','Excerpt',.2,1))
+[k kc ks] = mirkey(miraudio('Amaj5','Excerpt',.2,1))
+[k kc ks] = mirkey(miraudio('Cmaj','Excerpt',.2,1))
+
+pause, close all
+ 
+%Part 2. Let's analyze several extracts from 
+%real music. For each extract, try the 
+%following: 
+
+%2.1. Listen to the piece: 
+mirplay('vivaldi') 
+soundsc(sin(2*pi*440*(0:1/8192:1)))
+
+%2.2. Compute the chromagram of the 
+%whole extract. What tonal center could be 
+%inferred from the curve? Does it 
+%correspond to your expectation? 
+c = mirchromagram('vivaldi')
+
+%2.3. Compute the key strength related to 
+%the chromagram. Is the result congruent 
+%with the tonality inferred in 2.1. and 2.2.? 
+ks = mirkeystrength(c)
+[k kc ks] = mirkey(ks)
+
+%2.4. A more detailed representation of the 
+%key strengths can be obtained by 
+%computing the self-organizing map: 
+som = mirkeysom(c)
+
+pause, close all
+
+%2.5. Analyse in the same way other audio files
+[k kc ks] = mirkey('czardas')
+mirkeysom('czardas')
+
+pause, close all
+
+%Part 3. The temporal evolution of the 
+%tonal dimension can be assessed by 
+%decomposing first the audio into frames
+[k kc ks] = mirkey('czardas','frame')
+mirkeysom('czardas','frame')