IPython Notebook Audio Viewer

Audio.py

from IPython.core.display import DisplayObject
import StringIO
import base64
import struct
import sys

class Audio(DisplayObject):
    def __init__(self, data=None, rate=None, url=None, filename=None, autoplay=False):
        if(data is not None):
            buffer = StringIO.StringIO()
            buffer.write(b'RIFF')
            buffer.write(b'\x00\x00\x00\x00')
            buffer.write(b'WAVE')

            buffer.write(b'fmt ')
            if data.ndim == 1:
                noc = 1
            else:
                noc = data.shape[1]
            bits = data.dtype.itemsize * 8
            sbytes = rate*(bits // 8)*noc
            ba = noc * (bits // 8)
            buffer.write(struct.pack('<ihHIIHH', 16, 1, noc, rate, sbytes, ba, bits))

            # data chunk
            buffer.write(b'data')
            buffer.write(struct.pack('<i', data.nbytes))

            if data.dtype.byteorder == '>' or (data.dtype.byteorder == '=' and sys.byteorder == 'big'):
                data = data.byteswap()

            buffer.write(data.tostring())
            size = buffer.tell()
            buffer.seek(4)
            buffer.write(struct.pack('<i', size-8))
            
            self.data = buffer.getvalue()
        else:
            self.data = None

        self.autoplay = autoplay
        self.url = None if url is None else unicode(url)
        self.filename = None if filename is None else unicode(filename)

    def _repr_html_(self):
        src = """
        <audio controls="controls" style="width:600px" {autoplay}>
          <source controls src="{src}" type="audio/wav" />
          Your browser does not support the audio element.
        </audio>
        """.format(src=self.src_attr(),autoplay=self.autoplay_attr())
        return src

    def src_attr(self):
        if(self.data is not None):
            return """data:audio/wav;base64,{base64}""".format(base64=base64.encodestring(self.data))
        elif(self.url is not None):
            return self.url
        elif(self.filename is not None):
            return 'files/' + self.filename

    def autoplay_attr(self):
        if(self.autoplay):
            return 'autoplay="autoplay"'
        else:
            return ''

Try this using

import Audio
import numpy

data=2**13*numpy.sin(2*pi*440/44100*numpy.arange(44100))

Audio.Audio(data=data.astype(numpy.int16), rate=44100, autoplay=True)

or, if you already have a WAV file

import Audio

Audio.Audio(filename='something.wav', autoplay=True)

I have also posted a pullrequest to scipy that will integrate most of the (taken from scipy, but slightly modified) code in this class into the upstream codebase.