add python usage example

Makefile

@@ -25,15 +25,18 @@ inspect-ebur128graph: build
 run-tests: builddir
 	cd builddir && meson test -v
 
+run-example-py: builddir
+	GST_PLUGIN_PATH=$(realpath builddir) examples/example.py
+
 run-ebur128: build
 	GST_PLUGIN_PATH=$(realpath builddir) gst-launch-1.0 -m \
-	  filesrc location=example-audio/music.mp3 ! mpegaudioparse ! mpg123audiodec ! \
+	  filesrc location=examples/music.mp3 ! mpegaudioparse ! mpg123audiodec ! \
       ebur128 momentary=true shortterm=true global=true window=5000 range=true sample-peak=true true-peak=true interval=100000000 ! \
 	  autoaudiosink
 
 run-ebur128-with-seek: build
 	GST_PLUGIN_PATH=$(realpath builddir) gst-launch-1.0 -m \
-		filesrc location=example-audio/music.mp3 ! \
+		filesrc location=examples/music.mp3 ! \
 		mpegaudioparse ! mpg123audiodec ! \
 		ebur128 ! \
 		navseek ! \
@@ -44,7 +47,7 @@ run-ebur128-with-seek: build
 
 run-ebur128graph: build
 	GST_PLUGIN_PATH=$(realpath builddir) gst-launch-1.0 \
-		filesrc location=example-audio/music.mp3 ! mpegaudioparse ! mpg123audiodec ! tee name=t \
+		filesrc location=examples/music.mp3 ! mpegaudioparse ! mpg123audiodec ! tee name=t \
 		t. ! queue ! ebur128graph ! videoconvert ! ximagesink \
 		t. ! queue ! autoaudiosink
 

README.md

@@ -21,7 +21,7 @@ Configure and build:
     apt install build-essential meson libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev libebur128-dev libcairo-dev
 
     # For Testing
-    apt install gstreamer1.0-tools gstreamer1.0-plugins-base
+    apt install gstreamer1.0-tools gstreamer1.0-plugins-base gstreamer1.0-plugins-good
 
     # Build
     make
@@ -41,4 +41,10 @@ And Test it as with:
     make run-ebur128
     make run-ebur128graph
 
+## Use in your own App
+For an example on how to use the ebur128 Plugin in your own appl see [examples/example.py](example.py). To run it with the correct Plugin-Path, use
+
+    make run-example-py
+
+
 [MIT]: http://www.opensource.org/licenses/mit-license.php or COPYING.MIT

examples/example.py

@@ -0,0 +1,49 @@
+#!/usr/bin/env python3
+
+import gi
+
+gi.require_version('Gst', '1.0')
+from gi.repository import Gst, GLib
+
+Gst.init(None)
+
+pipeline = Gst.parse_launch("""
+    filesrc location=examples/music.mp3 ! mpegaudioparse ! mpg123audiodec ! \
+        ebur128 name=ebur128 momentary=true shortterm=true global=true window=5000 range=true sample-peak=true true-peak=true ! \
+        autoaudiosink
+""")
+
+element = pipeline.get_by_name("ebur128")
+
+def on_message(bus, message):
+    if message.type == Gst.MessageType.ELEMENT and message.src == element:
+        structure = message.get_structure()
+
+        success, timestamp = structure.get_uint64("timestamp")
+        success, momentary_loudness = structure.get_double("momentary")
+        success, shortterm_loudness = structure.get_double("shortterm")
+        success, global_loudness = structure.get_double("global")
+        success, window_loudness = structure.get_double("window")
+        success, loudness_range = structure.get_double("range")
+        true_peak = structure.get_value("true-peak")
+        sample_peak = structure.get_value("true-peak")
+
+        print({
+            "timestamp": timestamp,
+            "momentary_loudness": momentary_loudness,
+            "shortterm_loudness": shortterm_loudness,
+            "global_loudness": global_loudness,
+            "window_loudness": window_loudness,
+            "loudness_range": loudness_range,
+            "true_peak": true_peak,
+            "sample_peak": sample_peak
+        })
+
+bus = pipeline.get_bus()
+bus.add_signal_watch()
+bus.connect("message", on_message)
+
+pipeline.set_state(Gst.State.PLAYING)
+
+mainloop = GLib.MainLoop()
+mainloop.run()