My favorites | Sign in
Project Home Downloads Wiki Issues Source
Checkout   Browse   Changes    
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
#!/bin/env python

# usage: cfa.py sourcefile.txt outfile.mp3

# rule(frequency, amplitude, harmonic, loop=time|count, duration, fill=new|clone|quiet, a, d, s, r)
# ops: '':None, '=':assign, '+':increment, '*':scale

import sys, time, math, wave, random
from array import array # twice as fast as plain lists

"""
try:
import pymedia.audio.sound as sound
import pymedia.audio.acodec as acodec
import pymedia.muxer as muxer
except:
print "Please install PyMedia for mp3 output."
"""

pi = math.pi
sin = math.sin

sample_rate = 48000
channels = 1

def wave_dump(path, s):
# doesn't depend on pymedia, but doesn't seem to write more than 1 second
fw = wave.open(path, 'wb')
fw.setparams((channels, 2, sample_rate, 0, 'NONE',''))
for i in range(1000, len(s), 1000):
print i
s2 = s[i-1000: i]
fw.writeframesraw(s2)
fw.writeframesraw(s[i:])
fw.close()

def wave_dump_hack(path, s):
# rolled by own
# format info from http://technology.niagarac.on.ca/courses/ctec1631/WavFileFormat.html
def byte_pad(n, bytes):
assert n < 2**(bytes*8)
s = ''
for i in range(bytes):
s = chr(n%256) + s
n = n / 256
return s[::-1] # fix endian
data_len = 2 * len(s)
pack_len = 36 + data_len
fw = open(path, 'wb')
# RIFF chunk
fw.write('RIFF')
fw.write(byte_pad(pack_len, 4))
fw.write('WAVE')
# FORMAT chunk
fw.write('fmt ')
fw.write(byte_pad(0x10, 4))
fw.write(byte_pad(0x01, 2))
fw.write(byte_pad(channels, 2))
fw.write(byte_pad(channels*sample_rate, 4))
fw.write(byte_pad(channels*sample_rate*2, 4))
fw.write(byte_pad(2, 2))
fw.write(byte_pad(16, 2))
# DATA chunk
fw.write('data')
fw.write(byte_pad(data_len, 4))
for i in s:
fw.write(byte_pad(i, 2))
fw.close()

"""
def mp3_dump(path, s):
# still no clue why this inserts zeros and halves playpack
format = sound.AFMT_S16_LE
snd = sound.Output(sample_rate, channels, format)
snd.play(s)
params = {'id': acodec.getCodecID('mp3'),
'bitrate': 128000,
'sample_rate': sample_rate,
'channels': channels}
mx = muxer.Muxer('mp3')
stId = mx.addStream(muxer.CODEC_TYPE_AUDIO, params)
enc = acodec.Encoder(params)
fw = open(path, 'wb')
ss = mx.start()
fw.write(ss)
enc_frames = enc.encode(s)
for efr in enc_frames:
ss = mx.write(stId, efr)
if ss:
fw.write(ss)
if fw:
if mx:
ss = mx.end()
if ss:
fw.write(ss)
fw.close()
"""

def frange(start, stop, step):
"floating range with adjustable step size"
delta = stop - start
step = float(step)
fencepost = int(bool((delta/step)%1))
return [start + i*step for i in range(0, int(delta/step) + fencepost)]

def frange2(start, stop, count):
"floating range with adjustable number of elements"
if count == 0:
return []
if stop == start:
return [start] * count
return frange(start, stop, (stop-start)/count)

def safe_zip(a, b):
"unlike zip(), does not truncate to shortest"
# not at all safe for infinite lists
a_len = len(a)
b_len = len(b)
if a_len < b_len:
a.extend([0] * (b_len-a_len))
if a_len > b_len:
b.extend([0] * (a_len-b_len))
return zip(a,b)

def sin_builder(freq, amp=1.0, harmonic=1, phase=0, offset=0):
"generates a sin wave one fundamental long"
wavel = sample_rate / (freq*harmonic)
if wavel < 1:
return None # check for this!
phase = phase * pi / 180
return array('f', [amp * (sin(x + phase) + offset) for x in frange2(0, 2*pi, wavel)] * harmonic)

def adsr(wave, a, d, s, r):
"applies an envelope to a wave"
assert a+d+r < 1.0
l = len(wave)
shape_a = frange2(0, 1.0, l*a)
shape_d = frange2(1.0, s, l*d)
shape_s = [s] * int(l * (1-a-d-r))
shape_r = frange2(s, 0.0, l*r)
shape = array('f', shape_a + shape_d + shape_s + shape_r)
return array('f', [x*s for x,s in zip(wave, shape)])

def make_noise(wave, wav=None, noisy=True):
"plays/saves a wave"
clip = 2**15 - 1
w_peak = max(max(wave), abs(min(wave)))
scale = clip / w_peak
s = array('i', [int(i*scale) for i in wave])
#if noisy:
# snd.play(s)
if wav is not None:
#mp3_dump(mp3, s)
#wave_dump(wav, s)
wave_dump_hack(wav, s)

def loadfile(path):
"for samples"
f = wave.open(path, 'rb' )
# check format?
return array('f', [int(i) for i in f.readframes()])

def inherit_arg(parent_tuple, child_tuple):
"merge child and parent settings"
parent_value = parent_tuple[1]
op, value = child_tuple
if value is None:
return ('=', parent_value)
if op not in ['=', '+', '*']:
return ('=', parent_value)
if op == '=':
return ('=', value)
if op == '+':
return ('=', parent_value + value)
if op == '*':
return ('=', parent_value * value)

def repeat(sample, loop, duration, fill):
"not always safe, can not call() new random waveforms"
def new_sample():
if type(sample) == type(array('f', [])):
return sample
else:
return None
base = new_sample()
reps = 1
#if len(sample) == 0:
# return base
if loop == 'time':
reps = (duration - len(base)/float(sample_rate)) / (len(base)/float(sample_rate))
if loop == 'count':
reps = duration - 1
if fill == 'clone':
return base + base * int(reps) + base[0:int(len(base)*(reps%1))]
if fill == 'quiet':
return base + array('f', [0.0] * int(reps * len(base)))
if fill == 'new':
if loop == 'time':
while len(base) < duration * sample_rate:
base.extend(new_sample())
return base[0:duration * sample_rate]
if loop == 'count':
for i in range(reps):
base.extend(new_sample())
return base

class Rule(object):
"holds a mess of waveform settings"
def __init__(self, **kwargs): # name = ('op', value)
stock = { 'name':('',None), 'path':('', None),
'frequency':('',0), 'amplitude':('',1.0), 'harmonic':('',0),
'loop':('','time'), 'duration':('',1), 'fill':('','clone'),
'a':('',0), 'd':('',0), 's':('',1), 'r':('',0) , 'cp':('',None)}
for name in stock:
setattr(self, name, stock[name])
for name in kwargs:
setattr(self, name, kwargs[name])
def show(self):
print self.name, self.frequency, self.amplitude, self.cp
def wave(self):
"returns the associated sin wave or sample wave"
base = array('f', [])
if self.name[1] == 'sin':
base = sin_builder(self.frequency[1], amp=self.amplitude[1], harmonic=self.harmonic[1])
if self.name[1] == 'path':
base = loadfile(self.path[1])
if self.name[1] == 'none':
pass
return base
def recurse(self, sub_rule=None):
"build a new Rule by combining parent and child"
if sub_rule is None:
return self
#assert sub_rule.harmonic[1] > 0
if (self.frequency[1] + sub_rule.frequency[1]) * (self.harmonic[1] + sub_rule.harmonic[1]) > sample_rate:
return None # check for this!
# has to be a better way to do this
return Rule(name = inherit_arg(self.name, sub_rule.name),
path = inherit_arg(self.path, sub_rule.path),
frequency = inherit_arg(self.frequency, sub_rule.frequency),
amplitude = inherit_arg(self.amplitude, sub_rule.amplitude),
harmonic = inherit_arg(self.harmonic, sub_rule.harmonic),
loop = inherit_arg(self.loop, sub_rule.loop),
duration = inherit_arg(self.duration, sub_rule.duration),
fill = inherit_arg(self.fill, sub_rule.fill),
#cp = inherit_arg(self.cp, sub_rule.cp), inheriting cp yeilds infinite loops
a = inherit_arg(self.a, sub_rule.a),
d = inherit_arg(self.d, sub_rule.d),
s = inherit_arg(self.s, sub_rule.s),
r = inherit_arg(self.r, sub_rule.r))

class Rulebook:
"hold a bunch of rules"
def __init__(self):
"set up stock system rules"
self.book = {'sin':None, 'sample':None, 'none':None}
def add(self, name, rule):
if name in ['sin', 'sample', 'none']:
return
if name not in self.book:
self.book[name] = []
self.book[name].append(rule)
def call(self, name, parent_rule=None):
"creats a wave from the rule"
assert name in self.book
instructions = random.choice(self.book[name])
waveform_p = array('f', [])
waveform_s = array('f', [])
subwave = array('f', [])
subwave_cp = array('f', [])
for parallel_i in instructions:
waveform_s = array('f', [])
for serial_i in parallel_i:
j = serial_i
if parent_rule is not None:
j = parent_rule.recurse(serial_i)
if j is None:
continue
# conditions when repeat() is safe
if j.fill[1] in ['clone', 'quiet'] or j.name[1] in ['sin', 'sample', 'none']:
if j.name[1] in ['sin', 'sample', 'none']:
subwave = j.wave()
else:
subwave = self.call(j.name[1], j)
if subwave is None:
continue
subwave = repeat(subwave, j.loop[1], j.duration[1], j.fill[1])
else: # not safe to use repeat()
subwave = self.call(j.name[1], j)
if subwave is None:
continue
if j.loop[1] == 'time':
while len(subwave) < j.duration[1] * sample_rate:
subwave.extend(self.call(j.name[1], j))
if j.loop[1] == 'count':
for i in range(j.duration[1] - 1):
subwave.extend(self.call(j.name[1], j))
if j.cp[1] is not None:
subwave_cp = self.call(j.cp[1], j)
subwave = array('f', [a+b for a,b in safe_zip(subwave, subwave_cp)])
subwave = adsr(subwave, j.a[1], j.d[1], j.s[1], j.r[1])
waveform_s.extend(subwave)
waveform_p = array('f', [a+b for a,b in safe_zip(waveform_s, waveform_p)])
return waveform_p

# magical pyparsing BNF....
"""
variable name ::= "frequency" | "amplitude" | "harmonic" | "loop" | "duration" | "fill" | "a" | "d" | "s" | "r"
op_type ::= "=" | "+" | "*"
variable_value ::= number | "time" | "count" | "new" | "clone" | "quiet"
set_var ::= variable_name op_type variable_value
var_list ::= "" | set_var | set_var var_list
rule_contents ::= target_rule "(" var_list ")"
serial_sound ::= rule_contents rule_contents
parallel_sound ::= serial_sound | serial_sound "|" serial_sound | serial_sound "|" parallel_sound
rule ::= rule_name "=" parallel_sound
"""

def string_to_ast(s):
from pyparsing import Word, OneOrMore, ZeroOrMore, Group, Literal, Empty, alphas
L = Literal
word = Word(alphas + '_')
number = Word('-1234567890.')
#path = ???
variable_name = (L('frequency') ^ L('amplitude') ^ L('harmonic') ^ L('loop') ^ L('duration') ^ L('fill') ^ L('path') ^ L('cp') ^ L('a') ^ L('d') ^ L('s') ^ L('r'))
op_type = Word('=+*', exact=1)
variable_value = (L('time') ^ L('count') ^ L('new') ^ L('clone') ^ L('quiet') ^ number ^ word) # shoddy, no place for sample paths
set_var = Group(variable_name + op_type + variable_value)
target_rule = word
rule_contents = Group(target_rule + L('(').suppress() + Group(ZeroOrMore(set_var)) + L(')').suppress())
rule_serial = Group(OneOrMore(rule_contents))
rule_name = word
rule = (rule_name + L('=').suppress() + rule_serial) ^ ('|' + rule_serial)
s2 = s.split('\n')
ast = []
for line in s2:
line = line.strip()
if line == '': continue
try:
ast.append(rule.parseString(line))
except:
print 'FAILED ON: ' + line
raise
return ast

def typify(s):
"string to most restictive type"
try:
return int(s, 10)
except:
pass
try:
return float(s)
except:
pass
return s

def ast_to_rulebook(ast):
"a pain in the butt to debug"
s_r = []
p_r = []
rb = Rulebook()
old_rule_name = ''
for rule_name, serial_rules in ast:
s_r = []
if rule_name != '|' and p_r != []:
rb.add(old_rule_name, p_r)
p_r = []
for rule_call, settings in serial_rules:
kwargs = {'name':('=',rule_call)}
for var,op,value in settings:
kwargs[var] = (op, typify(value))
s_r.append(Rule(**kwargs))
p_r.append(s_r)
if rule_name != '|':
old_rule_name = rule_name
rb.add(old_rule_name, p_r)
return rb

example_string = """
startsound = repeat()
repeat = tone(frequency=440 loop=count duration=3 fill=new) tone(frequency=660 loop=count duration=3 fill=new)
tone = no_shape(harmonic=1 loop=time duration=1 fill=clone a=0.1 d=0.1 s=0.5 r=0.1)
a = sin()
| a(amplitude*0.5 harmonic+2)
a = sin()
| a(amplitude*0.25 harmonic+4)
no_shape = a(a=0 d=0 s=1 r=0)
"""

example_continuation = """
startsound = c(duration=0.5 cp=organ) d(duration=0.5 cp=organ) e(duration=0.5 cp=organ)
organ = shaped(harmonic=1 cp=overtones)
overtones = tone()
| overtones(amplitude*0.5 harmonic+4)
tone = sin(a=0 d=0 s=1 r=0)
shaped = none(a=0.1 d=0.1 s=0.5 r=0.1)
c = none(frequency=261.63)
d = none(frequency=293.66)
e = none(frequency=329.63)
f = none(frequency=349.23)
g = none(frequency=392.00)
a = none(frequency=440.00)
b = none(frequency=493.88)
"""


def example(a_string=None, wav=None):
if a_string is None:
a_string = example_string
if wav is None:
wave = 'test.wav'
print a_string + '\n'
rb = ast_to_rulebook(string_to_ast(a_string))
make_noise(rb.call('startsound'), wav, noisy=True)

tests = [
('Single sine',
"""startsound = sin(frequency=440 harmonic=1 duration=1)"""),

('Nested calls',
"""startsound = first()
first = second()
second = sin(frequency=440 harmonic=1 duration=1)"""),

('Nested passing',
"""startsound = first(frequency=440 harmonic=1 duration=1)
first = second()
second = sin()"""),

('Sequential sounds',
"""startsound = sin(frequency=440 harmonic=1 duration=1 fill=clone) sin(frequency=880 harmonic=1 duration=1)"""),

('Parallel sounds',
"""startsound = sin(frequency=440 harmonic=1 duration=1)
| sin(frequency=880 harmonic=1 duration=1)"""),

('ADSR shaping',
"""startsound = sin(frequency=440 harmonic=1 duration=1 a=0.2 d=0.2 s=0.3 r=0.2)"""),

('Recursion',
"""startsound = o(frequency=440 harmonic=1 duration=1)
o = sin()
| o(harmonic+2)"""),

('Probabilistic',
"""startsound = o() o() o() o() o()
o = sin(frequency=440 harmonic=1 duration=0.2)
o = sin(frequency=880 harmonic=1 duration=0.2)""")

]


def testsuite():
for i, test in enumerate(tests):
title, cfa = test
output = 'test_' + str(i) + '.wav'
print output + ': ' + title
example(cfa, output)

def main(argv=None):
if argv is None:
argv = sys.argv
if len(argv) == 1:
sys.exit(example())
if argv[1] == 'testsuite':
testsuite()
sys.exit()
source_f = open(argv[1])
target_f = argv[2]
source_t = ''.join(source_f.readlines())
rb = ast_to_rulebook(string_to_ast(source_t))
make_noise(rb.call('startsound'), target_f)

if __name__ == "__main__":
sys.exit(main())
#example()
#import cProfile
#cProfile.run("example()", sort=1)

Change log

r5 by keenerd on May 4, 2008   Diff
A few test cases added.  Run with "python
cfa.py testsuite"
Go to: 
Project members, sign in to write a code review

Older revisions

r4 by keenerd on May 1, 2008   Diff
Home rolled WAV saver.  No pyMedia
dependency.  Windows and OSX user
rejoice.
r3 by keenerd on Apr 29, 2008   Diff
friendlier parse failures, first
(failed) attempt at continuations
r2 by keenerd on Apr 28, 2008   Diff
Switched everything over to built-in
arrays, doubled speed.
All revisions of this file

File info

Size: 16292 bytes, 479 lines
Powered by Google Project Hosting