def fingerprint(samplerate, channels, pcmiter, maxlength=MAX_AUDIO_LENGTH):
"""Fingerprint audio data given its sample rate and number of
channels. pcmiter should be an iterable containing blocks of PCM
data as byte strings. Raises a FingerprintGenerationError if
anything goes wrong.
"""
# Maximum number of samples to decode.
endposition = samplerate * channels * maxlength
try:
fper = chromaprint.Fingerprinter()
fper.start(samplerate, channels)
position = 0 # Samples of audio fed to the fingerprinter.
for block in pcmiter:
fper.feed(block)
position += len(block) // 2 # 2 bytes/sample.
if position >= endposition:
break
return fper.finish()
except chromaprint.FingerprintError:
raise FingerprintGenerationError("fingerprint calculation failed")
def fingerprint_AudioSegment(audio_segment, maxlength=120000):
"""Fingerprint audio data given a pydub AudioSegment object.
Raises a FingerprintGenerationError if anything goes wrong.
Based on acoustid.py's fingerprint function.
"""
maxlength /= 1000
endposition = audio_segment.frame_rate * audio_segment.channels * maxlength
try:
fper = chromaprint.Fingerprinter()
fper.start(audio_segment.frame_rate, audio_segment.channels)
position = 0 # Samples of audio fed to the fingerprinter.
for start in range(0, len(audio_segment.raw_data), 4096):
block = audio_segment.raw_data[start:start + 4096]
fper.feed(block)
position += len(block) // 2 # 2 bytes/sample.
if position >= endposition:
break
return fper.finish()
except chromaprint.FingerprintError:
raise chromaprint.FingerprintGenerationError("fingerprint calculation "
"failed")
import wave
import chromaprint
from optparse import OptionParser
parser = OptionParser(usage="usage: %prog [options] filename")
parser.add_option("-l", "--length", dest="length", default=30, type='int',
help="fingerprint audio length", metavar="LENGTH")
(options, args) = parser.parse_args()
if not args:
parser.error("missing filename")
wav = wave.open(args[0], 'r')
fpgen = chromaprint.Fingerprinter()
fpgen.start(wav.getframerate(), wav.getnchannels())
length = 0
while length < options.length:
frames = wav.readframes(1024 * 4)
if not frames:
break
fpgen.feed(frames)
length += float(len(frames)) / wav.getsampwidth() / wav.getnchannels() / wav.getframerate()
fp = fpgen.finish()
total_length = wav.getnframes() / wav.getframerate()
print "FILE:", args[0]
print "CHANNELS:", wav.getnchannels()
print "SAMPLE RATE:", wav.getframerate()
print "LENGTH:", total_length
