chore: move examples to dedicated directory

examples/recordtest.py

@@ -0,0 +1,66 @@
+#!/usr/bin/env python3
+# -*- mode: python; indent-tabs-mode: t; c-basic-offset: 4; tab-width: 4 -*-
+
+## recordtest.py
+##
+## This is an example of a simple sound capture script.
+##
+## The script opens an ALSA pcm device for sound capture, sets
+## various attributes of the capture, and reads in a loop,
+## writing the data to standard out.
+##
+## To test it out do the following:
+## python recordtest.py out.raw # talk to the microphone
+## aplay -r 8000 -f S16_LE -c 1 out.raw
+
+#!/usr/bin/env python
+
+from __future__ import print_function
+
+import sys
+import time
+import getopt
+import alsaaudio
+
+def usage():
+	print('usage: recordtest.py [-d <device>] <file>', file=sys.stderr)
+	sys.exit(2)
+
+if __name__ == '__main__':
+
+	device = 'default'
+
+	opts, args = getopt.getopt(sys.argv[1:], 'd:')
+	for o, a in opts:
+		if o == '-d':
+			device = a
+
+	if not args:
+		usage()
+
+	f = open(args[0], 'wb')
+
+	# Open the device in nonblocking capture mode in mono, with a sampling rate of 44100 Hz
+	# and 16 bit little endian samples
+	# The period size controls the internal number of frames per period.
+	# The significance of this parameter is documented in the ALSA api.
+	# For our purposes, it is suficcient to know that reads from the device
+	# will return this many frames. Each frame being 2 bytes long.
+	# This means that the reads below will return either 320 bytes of data
+	# or 0 bytes of data. The latter is possible because we are in nonblocking
+	# mode.
+	inp = alsaaudio.PCM(alsaaudio.PCM_CAPTURE, alsaaudio.PCM_NONBLOCK,
+		channels=1, rate=44100, format=alsaaudio.PCM_FORMAT_S16_LE,
+		periodsize=160, device=device)
+
+	loops = 1000000
+	while loops > 0:
+		loops -= 1
+		# Read data from device
+		l, data = inp.read()
+
+		if l < 0:
+			print("Capture buffer overrun! Continuing nonetheless ...")
+		elif l:
+			f.write(data)
+			time.sleep(.001)