Music: a song's fingerprint¶
A short song is turned into a picture. Time goes across, pitch goes up, and the louder a pitch is, the brighter it is. Each note is a bright dash, and the low bass notes run along the bottom. Click to play the song, and a line shows where it is. The picture is also saved as fingerprint.png. With no sound device, the song plays silently.
How it works¶
- f.melody() makes the tune, and makes the bass again with wave="sine" and volume=0.35. f.mix() adds the two into one song. The bass is quiet, so the sum does not clip.
- f.spectrogram(song, WIDTH, HEIGHT) turns the whole sound into a picture. Its brightest colour is the fill colour at that moment, so setup() calls f.fill() first.
- fingerprint.save("fingerprint.png") writes the picture, and f.image() draws it.
- The picture runs from 40 Hz to 16,000 Hz. pitch_height() uses a log to find where a note name sits, so the side labels C3, C4, C5 and C6 are in the right place.
- mouse_pressed() calls song.play(). While song.is_playing(), the line sits at song.current_time() / song.duration() of the way across.
Make it yours¶
- Change the notes in LEAD or BASS.
- Change TEMPO. A faster song makes a shorter, tighter picture.
- Change f.fill(255, 150, 60) to another colour. The whole picture changes colour.
- Change wave="sine" to wave="square" in the bass. Square waves have many more lines above each note.
- Make the picture bigger: raise WIDTH and HEIGHT, and the size in f.size().
The code¶
Copy it into a file and run it.
"""Music: a song's fingerprint
A short song is turned into a picture. Time goes across, pitch goes up, and the louder a pitch
is, the brighter it is. Each note is a bright dash, and the low bass notes run along the bottom.
Click to play the song, and a line shows where it is. The picture is also saved as
fingerprint.png. With no sound device, the song plays silently.
How it works:
- f.melody() makes the tune, and makes the bass again with wave="sine" and volume=0.35. f.mix()
adds the two into one song. The bass is quiet, so the sum does not clip.
- f.spectrogram(song, WIDTH, HEIGHT) turns the whole sound into a picture. Its brightest colour is
the fill colour at that moment, so setup() calls f.fill() first.
- fingerprint.save("fingerprint.png") writes the picture, and f.image() draws it.
- The picture runs from 40 Hz to 16,000 Hz. pitch_height() uses a log to find where a note name
sits, so the side labels C3, C4, C5 and C6 are in the right place.
- mouse_pressed() calls song.play(). While song.is_playing(), the line sits at
song.current_time() / song.duration() of the way across.
Make it yours:
- Change the notes in LEAD or BASS.
- Change TEMPO. A faster song makes a shorter, tighter picture.
- Change f.fill(255, 150, 60) to another colour. The whole picture changes colour.
- Change wave="sine" to wave="square" in the bass. Square waves have many more lines above each
note.
- Make the picture bigger: raise WIDTH and HEIGHT, and the size in f.size().
"""
import funground as f
TEMPO = 140
LEAD = "C5 E5 G5 E5 C5:2 D5 F5 A5 F5 D5:2 E5 G5 B5 G5 E5:2 C5:4"
BASS = "C3:6 D3:6 E3:6 C3:4"
# The tune in melody's soft voice, and a quieter sine bass, so the two together do not need
# mix() to squash them.
song = f.mix(f.melody(LEAD, tempo=TEMPO),
f.melody(BASS, tempo=TEMPO, wave="sine", volume=0.35))
LEFT, TOP, WIDTH, HEIGHT = 50, 50, 440, 220
fingerprint = None
def setup():
global fingerprint
f.size(520, 320)
f.fill(255, 150, 60) # the brightest colour in the picture
fingerprint = f.spectrogram(song, WIDTH, HEIGHT)
fingerprint.save("fingerprint.png")
f.text_size(12)
def pitch_height(name):
"""How far down the picture a note is (the picture runs from 40 Hz to 16 kHz)."""
from math import log
return TOP + HEIGHT * (1 - log(f.note_to_frequency(name) / 40) / log(16000 / 40))
def draw():
f.background(20)
f.image(fingerprint, LEFT, TOP)
# a few notes down the side
f.no_stroke()
f.fill(170)
f.text_align("right", "center")
for name in ("C3", "C4", "C5", "C6"):
f.text(name, LEFT - 8, pitch_height(name))
f.text_align("left", "top")
f.text("click to play", LEFT, TOP + HEIGHT + 14)
# where the song is now
if song.is_playing():
x = LEFT + WIDTH * song.current_time() / song.duration()
f.stroke(255)
f.stroke_width(2)
f.line(x, TOP, x, TOP + HEIGHT)
def mouse_pressed():
song.play()
f.run()