ref: 1c190d586b926e2ffd3aa78e8aef822fdc995163
dir: /interfaces/python/aubioinput.py/
#! /usr/bin/python
import pygst
pygst.require('0.10')
import gst
import gobject
gobject.threads_init ()
def gst_buffer_to_numpy_array(buffer, chan):
import numpy
samples = numpy.frombuffer(buffer.data, dtype=numpy.float32)
samples.resize([len(samples)/chan, chan])
return samples.T
class AubioSink(gst.BaseSink):
_caps = gst.caps_from_string('audio/x-raw-float, \
rate=[ 1, 2147483647 ], \
channels=[ 1, 2147483647 ], \
endianness={ 1234, 4321 }, \
width=32')
__gsttemplates__ = (
gst.PadTemplate ("sink",
gst.PAD_SINK,
gst.PAD_ALWAYS,
_caps),
)
def __init__(self, name, process):
self.__gobject_init__()
self.set_name(name)
self.process = process
self.adapter = gst.Adapter()
self.set_property('sync', False)
self.pos = 0
def set_property(self, name, value):
if name == 'hopsize':
# blocksize is in byte, convert from hopsize
from struct import calcsize
self.set_property('blocksize', value * calcsize('f'))
else:
super(gst.BaseSink, self).set_property(name, value)
def do_render(self, buffer):
blocksize = self.get_property('blocksize')
caps = buffer.get_caps()
chan = caps[0]['channels']
self.adapter.push(buffer)
while self.adapter.available() >= blocksize:
block = self.adapter.take_buffer(blocksize)
v = gst_buffer_to_numpy_array(block, chan)
if self.process:
self.process(v, self.pos)
self.pos += 1
return gst.FLOW_OK
gobject.type_register(AubioSink)
class aubioinput:
def __init__(self, location, process = None, hopsize = 512,
caps = None):
from os.path import isfile
if not isfile(location):
raise ValueError, "location should be a file"
src = gst.element_factory_make('filesrc')
src.set_property('location', location)
dec = gst.element_factory_make('decodebin')
dec.connect('new-decoded-pad', self.on_new_decoded_pad)
conv = gst.element_factory_make('audioconvert')
rsmpl = gst.element_factory_make('audioresample')
capsfilter = gst.element_factory_make('capsfilter')
if caps:
capsfilter.set_property('caps', gst.caps_from_string(caps))
sink = AubioSink("AubioSink", process = process)
sink.set_property('hopsize', hopsize) # * calcsize('f'))
self.pipeline = gst.Pipeline()
self.bus = self.pipeline.get_bus()
self.bus.add_signal_watch()
self.bus.connect('message::eos', self.on_eos)
self.apad = conv.get_pad('sink')
self.pipeline.add(src, dec, conv, rsmpl, capsfilter, sink)
src.link(dec)
gst.element_link_many(conv, rsmpl, capsfilter, sink)
self.mainloop = gobject.MainLoop()
self.pipeline.set_state(gst.STATE_PLAYING)
self.mainloop.run()
def on_new_decoded_pad(self, element, pad, last):
caps = pad.get_caps()
name = caps[0].get_name()
#print 'on_new_decoded_pad:', name
if name == 'audio/x-raw-float' or name == 'audio/x-raw-int':
if not self.apad.is_linked(): # Only link once
pad.link(self.apad)
def on_eos(self, bus, msg):
self.bus.remove_signal_watch()
self.pipeline.set_state(gst.STATE_PAUSED)
self.mainloop.quit()
if __name__ == '__main__':
import sys
if len(sys.argv) < 2:
print "Usage: %s <filename>" % sys.argv[0]
sys.exit(1)
for filename in sys.argv[1:]:
peak = [0., 0.]
def process(buf, hop):
peak[0] = max( peak[0], abs(buf.max()) )
peak[1] = min( peak[1], abs(buf.min()) )
aubioinput(filename, process = process, hopsize = 512)
print "Finished reading %s, peak value is %f" % (filename, min(peak))