python/demos/demo_pysoundcard_play.py: added simple example using pysoundcard

diff --git a/python/demos/demo_pysoundcard_play.py b/python/demos/demo_pysoundcard_play.py
new file mode 100755 (executable)
index 0000000..b0bf70c
--- /dev/null
+++ b/python/demos/demo_pysoundcard_play.py
@@ -0,0 +1,24 @@
+#! /usr/bin/env python
+
+def play_source(source_path):
+    """Play an audio file using pysoundcard."""
+
+    from aubio import source
+    from pysoundcard import Stream
+    
+    hop_size = 256
+    f = source(source_path, hop_size = hop_size)
+    samplerate = f.samplerate
+
+    s = Stream(sample_rate = samplerate, block_length = hop_size)
+    s.start()
+    read = 0
+    while 1:
+        vec, read = f()
+        s.write(vec)
+        if read < hop_size: break
+    s.stop()
+
+if __name__ == '__main__':
+    import sys
+    play_source(sys.argv[1])