24 from itertools
import imap,chain,izip
29 print >>sys.stderr,
"Error: Numerical Python not found" 33 from scikits.audiolab
import Sndfile
35 print >>sys.stderr,
"Error: scikits.audiolab not found" 41 print >>sys.stderr,
"Error: purehuff module not found" 45 """group list elements""" 48 l = [v
for _,v
in izip(xrange(n),it)]
54 def arrayformatter(seq,perline=40):
55 """format list output linewise""" 56 return ",\n".join(
",".join(imap(str,s))
for s
in grouper(perline,seq))
58 if __name__ ==
"__main__":
59 from optparse
import OptionParser
60 parser = OptionParser()
61 parser.add_option(
"--bits", type=
"int", default=8, dest=
"bits",help=
"bit resolution")
62 parser.add_option(
"--sndfile", dest=
"sndfile",help=
"input sound file")
63 parser.add_option(
"--hdrfile", dest=
"hdrfile",help=
"output C header file")
64 parser.add_option(
"--name", dest=
"name",help=
"prefix for tables and constants in file")
65 parser.add_option(
"--plothist", type=
"int", default=0, dest=
"plothist",help=
"plot histogram")
66 (options, args) = parser.parse_args()
68 if not options.sndfile:
69 print >>sys.stderr,
"Error: --sndfile argument required" 72 sndf = Sndfile(options.sndfile,
'r') 73 sound = sndf.read_frames(sndf.nframes) 78 if len(sound.shape) > 1:
79 sound = N.mean(sound,axis=1)
82 sound8 = N.clip((sound*(2**(options.bits-1))).astype(int),-2**(options.bits-1),2**(options.bits-1)-1)
84 dsound8 = map(int,chain((sound8[0],),imap(
lambda x: x[1]-x[0],izip(sound8[:-1],sound8[1:]))))
86 print >>sys.stderr,
"min/max: %i/%i"%(N.min(sound8),N.max(sound8))
87 print >>sys.stderr,
"data bits: %i"%(len(sound8)*options.bits)
89 hist = purehuff.histogram(dsound8)
95 print >>sys.stderr,
"Plotting needs pylab" 97 from collections
import defaultdict
98 d = defaultdict(float)
101 x = range(min(d.iterkeys()),max(d.iterkeys())+1)
102 y = [d[xi]
for xi
in x]
104 P.title(
"Histogram of sample differentials, file %s"%os.path.split(options.sndfile)[-1])
105 P.plot(x,y,marker=
'x')
108 hufftree = purehuff.HuffTree(hist)
111 decoder = hufftree.decoder()
113 encoder = hufftree.encoder()
115 enc = encoder(dsound8)
117 print >>sys.stderr,
"encoded bits: %i"%len(enc)
118 print >>sys.stderr,
"ratio: %.0f%%"%((len(enc)*100.)/(len(sound8)*8))
119 print >>sys.stderr,
"decoder length: %.0f words"%(len(decoder.huff))
122 hdrf = file(options.hdrfile,
'wt')
123 print >>hdrf,
"// generated by Mozzi/extras/python/audio2huff.py \n" 124 print >>hdrf,
"#ifndef " + options.name +
"_H_" 125 print >>hdrf,
"#define " + options.name +
"_H_\n" 126 print >>hdrf,
'#if ARDUINO >= 100' 127 print >>hdrf,
'#include "Arduino.h"' 129 print >>hdrf,
'#include "WProgram.h"' 130 print >>hdrf,
'#endif \n' 131 print >>hdrf,
'#include "mozzi_pgmspace.h"\n \n' 132 print >>hdrf,
"#define " + options.name +
"_SAMPLERATE %i"%fs
133 print >>hdrf,
"#define " + options.name +
"_SAMPLE_BITS %i"%options.bits
134 print >>hdrf,
'CONSTTABLE_STORAGE(int) ' + options.name +
'_HUFFMAN[%i] = {\n%s\n};'%(len(decoder.huff),arrayformatter(decoder.huff))
135 print >>hdrf,
'unsigned long const ' + options.name +
'_SOUNDDATA_BITS = %iL;'%len(enc)
136 print >>hdrf,
'CONSTTABLE_STORAGE(unsigned char) ' + options.name +
'_SOUNDDATA[] = {\n%s\n};'%arrayformatter(enc.data)
137 print >>hdrf,
"#endif /* " + options.name +
"_H_ */"