%matplotlib inline
from pylab import *

from IPython.display import Audio # awesome IPython tool to embed audio directly in the notebook

from scipy.signal import square

t = arange(0, 0.1, 1/10000.)
t.shape

plot(t, square(2 * pi * 100 * t))
title("A square wave!")
ylim(-1.1, 1.1)
grid(True)

Audio(data=square(2 * pi * 100 * t), rate=5000) 

from IPython.html.widgets import interact, fixed
from IPython.display import display

def play_square_sound(freq, duration, duty_cycle = 0.5, sample_freq=10.e3, plot_signal=False):
    t = arange(0, duration, 1/sample_freq)
    s = square(2 * pi * freq * t, duty=duty_cycle)
    if plot_signal: 
        plot(t, s)
    display(Audio(s, rate=sample_freq))

interact(play_square_sound,
         freq=(10, 1000, 50),
         duration=(0.1, 0.5, 0.1),
         duty_cycle=(0.1, 0.9, 0.01),
         sample_freq=fixed(10e3),
         plot_signal=fixed(True))

def play_square_sound_with_envelope(freq, duration, duty_cycle = 0.5, sample_freq=10.e3, envelope_duration=0.1):
    t = arange(0, duration, 1/sample_freq)
    s = square(2 * pi * freq * t, duty=duty_cycle) * (1 - exp(-t * envelope_duration))
    plot(t, s)
    display(Audio(s, rate=sample_freq))

interact(play_square_sound_with_envelope,
     freq=(10, 1000, 50),
     duration=(0.1, 0.5, 0.1),
     duty_cycle=(0.1, 0.9, 0.01),
     sample_freq=fixed(10e3),
     envelope_duration=(0.1, 100, 0.1))

tetris = "e6,8b,8c6,8d6,16e6,16d6,8c6,8b,a,8a,8c6,e6,8d6,8c6,b,8b,8c6,d6,e6,c6,a,2a,8p,d6,8f6,a6,8g6,8f6,e6,8e6,8c6,e6,8d6,8c6,b,8b,8c6,d6,e6,c6,a,a"

note = tetris.split(",")[2]
note

import re
duration = re.compile("^[0-9]+")
pitch = re.compile("[\D]+[\d]*")

print duration.findall(note)
print pitch.findall(note)

t_max = duration.findall(note)
t_max = 1/float(t_max[0])
t_max

pitch.findall(note)[0].split("123456")

try:
    octave = ["1", "2", "3", "4", "5", "6", "7"].index(pitch.findall(note)[0][-1]) + 1 
    height = pitch.findall(note)[0][:-1]
except:
    height = pitch.findall(note)[0]
    octave = 4
print "height= {0}, octave= {1}".format(height, octave)

freq = 440 * 2 ** ((["a", "a#", "b", "c", "c#", "d", "d#", "e", "f", "f#", "g", "g#"].index(height) / 12. + octave - 5)) 
freq

wave = play_square_sound(freq, 4 * t_max)

def play_melody(melody, sample_freq=10.e3, bpm=50):
    duration = re.compile("^[0-9]+")
    pitch = re.compile("[\D]+[\d]*") 
    measure_duration = 4 * 60. / bpm #usually it's 4/4 measures
    output = zeros((0,))
    for note in melody.split(','):
        # regexp matching
        duration_match = duration.findall(note)
        pitch_match = pitch.findall(note)
        
        # duration 
        if len(duration_match) == 0:
            t_max = 1/4.
        else:
            t_max = 1/float(duration_match[0])
        if "." in pitch_match[0]:
            t_max *= 1.5
            pitch_match[0] = "".join(pitch_match[0].split("."))
        t_max = t_max * measure_duration
        
        # pitch
        if pitch_match[0] == 'p':
            freq = 0
        else:
            if pitch_match[0][-1] in ["4", "5", "6", "7"]: # octave is known
                octave = ["4", "5", "6", "7"].index(pitch_match[0][-1]) + 4 
                height = pitch_match[0][:-1]
            else: # octave is not known
                octave = 5
                height = pitch_match[0]
            freq = 261.626 * 2 ** ((["c", "c#", "d", "d#", "e", "f", "f#", "g", "g#", "a", "a#", "b"].index(height) / 12. + octave - 4))  
            
        # generate sound
        t = arange(0, t_max, 1/sample_freq)
        wave = square(2 * pi * freq * t)
        
        # append to output
        output = hstack((output, wave))
    
    display(Audio(output, rate=sample_freq)) 

play_melody(tetris, sample_freq=20.e3, bpm=160)

play_melody("d6,32p,c.6,32p,8a,8c6,8a#,16a,16g,f,c,8a,8c6,8g,8a,f,c,d,8d,8e,8g,8f,8e,8d,c,c,c", bpm=140)

play_melody("d#6,b,c#6,a#,16b,16g#,16a#,16b,16b,16g#,16a#,16b,c#6,g,d#6,16p,16g#,16a#,16b,c#6,16p,16b,16a#,g#,g,g#,16f,16g,16g#,16a#,8d#.6,32d#6,32p,32d#6,32p,32d#6,32p,16d6,16d#6,8f.6,16d6,8a#,8p,8f#6,8d#6,8f#,8g#,a#.,16p,16a#,8d#.6,16f6,16f#6,16f6,16d#6,16a#,8g#.,16b,8d#6,16f6,16d#6,8a#.,16b,16a#,16g#,16f,16f#,d#", bpm=63)

play_melody("16e6,16e6,32p,8e6,16c6,8e6,8g6,8p,8g,8p,8c6,16p,8g,16p,8e,16p,8a,8b,16a#,8a,16g.,16e6,16g6,8a6,16f6,8g6,8e6,16c6,16d6,8b,16p,8c6,16p,8g,16p,8e,16p,8a,8b,16a#,8a,16g.,16e6,16g6,8a6,16f6,8g6,8e6,16c6,16d6,8b,8p,16g6,16f#6,16f6,16d#6,16p,16e6,16p,16g#,16a,16c6,16p,16a,16c6,16d6,8p,16g6,16f#6,16f6,16d#6,16p,16e6,16p,16c7,16p,16c7,16c7,p,16g6,16f#6,16f6,16d#6,16p,16e6,16p,16g#,16a,16c6,16p,16a,16c6,16d6,8p,16d#6,8p,16d6,8p,16c6", bpm=100)

play_melody("32c,32p,32c7,32p,32a5,32p,32a,32p,32a#5,32p,32a#,2p,32c,32p,32c7,32p,32a5,32p,32a,32p,32a#5,32p,32a#,2p,32f5,32p,32f,32p,32d5,32p,32d,32p,32d#5,32p,32d#,2p,32f5,32p,32f,32p,32d5,32p,32d,32p,32d#5,32p,32d#", bpm=100)

play_melody("a#,f.,8a#,16a#,16c6,16d6,16d#6,2f6,8p,8f6,16f.6,16f#6,16g#.6,2a#.6,16a#.6,16g#6,16f#.6,8g#.6,16f#.6,2f6,f6,8d#6,16d#6,16f6,2f#6,8f6,8d#6,8c#6,16c#6,16d#6,2f6,8d#6,8c#6,8c6,16c6,16d6,2e6,g6,8f6,16f,16f,8f,16f,16f,8f,16f,16f,8f,8f,a#,f.,8a#,16a#,16c6,16d6,16d#6,2f6,8p,8f6,16f.6,16f#6,16g#.6,2a#.6,c#7,c7,2a6,f6,2f#.6,a#6,a6,2f6,f6,2f#.6,a#6,a6,2f6,d6,2d#.6,f#6,f6,2c#6,a#,c6,16d6,2e6,g6,8f6,16f,16f,8f,16f,16f,8f,16f,16f,8f,8f", bpm=150)