Tidy up and first python examples

README.md

@@ -39,7 +39,12 @@ Good GStreamer Python resources include:
 
 * [Getting started with GStreamer with Python](https://www.jonobacon.com/2006/08/28/getting-started-with-gstreamer-with-python/)
 * [Python GStreamer Tutorial](http://brettviren.github.io/pygst-tutorial-org/pygst-tutorial.html)
-* [Function reference](http://lazka.github.io/pgi-docs/#GstApp-1.0)
+* [Function reference](http://lazka.github.io/pgi-docs/#Gst-1.0)
+* [Nice example script](https://github.com/rabits/rstream/blob/master/rstream.py)
+
+### C++ with GStreamer
+
+My favourite reference is [Valadoc](https://valadoc.org/gstreamer-1.0/index.htm)
 
 # Problems or suggestions with this guide?
 

basics.md

@@ -109,3 +109,6 @@ gst-launch-1.0 filesrc location=$SRC ! \
     autovideosink
 ```
 
+### Play files back to back
+
+See (https://coaxion.net/blog/2014/08/concatenate-multiple-streams-gaplessly-with-gstreamer/)[https://coaxion.net/blog/2014/08/concatenate-multiple-streams-gaplessly-with-gstreamer/]

mixing.md

@@ -70,5 +70,17 @@ gst-launch-1.0   \
     mix.
 ```
 
+### Compositor with just one sources
 
+It is possible for a compositor to have just one source. This example has the test source of a bouncing ball. It also has the audio test source included (muxed).
 
+```
+gst-launch-1.0   \
+    videotestsrc pattern=ball ! \
+    decodebin ! \
+    compositor name=mix sink_0::alpha=1 ! \
+    x264enc ! muxer. \
+    audiotestsrc ! avenc_ac3 ! muxer. \
+    mpegtsmux name=muxer ! queue ! \
+    tcpserversink host=127.0.0.1 port=7001 recover-policy=keyframe sync-method=latest-keyframe sync=false
+```

network_transfer.md

@@ -92,15 +92,18 @@ To send a test stream:
 ```
 gst-launch-1.0 \
     audiotestsrc ! \
-    avenc_ac3 ! mpegtsmux ! tcpserversink port=7001 host=0.0.0.0
+    avenc_ac3 ! mpegtsmux ! \
+    tcpserversink port=7001 host=0.0.0.0
 ```
 
 To send a file:
 
 ```
 # Make sure $SRC is set to an audio file (e.g. an MP3 file)
-gst-launch-1.0 -v filesrc location=$AUDIO_SRC ! \
-    mpegaudioparse ! tcpserversink port=7001 host=0.0.0.0
+gst-launch-1.0 \
+    filesrc location=$AUDIO_SRC ! \
+    mpegaudioparse ! \
+    tcpserversink port=7001 host=0.0.0.0
 ```
 
 And to receive:

python_examples/headless.py

@@ -0,0 +1,30 @@
+#!/usr/bin/env python
+#
+# Sends a test stream to a fake sink.
+# This is utterly pointless, but allows easy testing of GStreamer
+# Python on a remote box that doesn't have video.
+#
+# Equivalent to:
+#    gst-launch-1.0 videotestsrc ! fakesink
+#
+
+import gi
+gi.require_version('Gst', '1.0')
+from gi.repository import GObject, Gst
+import os
+
+Gst.init()
+mainloop = GObject.MainLoop()
+
+pipeline =  Gst.Pipeline.new("pipe")
+
+videotestsrc = Gst.ElementFactory.make("videotestsrc", "videotestsrc")
+fakesink = Gst.ElementFactory.make("fakesink", "fakesink")
+
+pipeline.add(videotestsrc)
+pipeline.add(fakesink)
+
+videotestsrc.link(fakesink)
+
+pipeline.set_state(Gst.State.PLAYING)
+mainloop.run()

python_examples/playbin.py

@@ -1,5 +1,7 @@
 #!/usr/bin/env python
 #
+# Plays a file to screen.
+#
 # Make sure the environment variable SRC is set to a playable file
 # e.g.
 #   export SRC='/tmp/me.mp4'
@@ -13,9 +15,8 @@ import os
 Gst.init()
 mainloop = GObject.MainLoop()
 
-pl = Gst.ElementFactory.make("playbin", "player")
-pl.set_property('uri','file://'+os.environ['SRC'])
+pipeline = Gst.ElementFactory.make("playbin", "player")
+pipeline.set_property('uri','file://'+os.environ['SRC'])
 
-#running the playbin
-pl.set_state(Gst.State.PLAYING)
+pipeline.set_state(Gst.State.PLAYING)
 mainloop.run()

python_examples/show_test_stream.py

@@ -0,0 +1,31 @@
+#!/usr/bin/env python
+#
+# Plays a test screen to screen.
+#
+# Equivalent to:
+#    gst-launch-1.0 videotestsrc ! videoconvert ! autovideosink
+#
+
+import gi
+gi.require_version('Gst', '1.0')
+from gi.repository import GObject, Gst
+import os
+
+Gst.init()
+mainloop = GObject.MainLoop()
+
+pipeline =  Gst.Pipeline.new("pipe")
+
+videotestsrc = Gst.ElementFactory.make("videotestsrc", "videotestsrc")
+videoconvert = Gst.ElementFactory.make("videoconvert", "videoconvert")
+autovideosink = Gst.ElementFactory.make("autovideosink", "autovideosink")
+
+pipeline.add(videotestsrc)
+pipeline.add(videoconvert)
+pipeline.add(autovideosink)
+
+videotestsrc.link(videoconvert)
+videoconvert.link(autovideosink)
+
+pipeline.set_state(Gst.State.PLAYING)
+mainloop.run()

rtmp.md

@@ -136,6 +136,8 @@ gst-launch-1.0 videotestsrc is-live=true ! \
 
 ### Send a file over RTMP
 
+Audio & video:
+
 ```
 gst-launch-1.0 filesrc location=$SRC ! \
     qtdemux name=demux \
@@ -148,6 +150,17 @@ gst-launch-1.0 filesrc location=$SRC ! \
     voaacenc bitrate=96000 ! audio/mpeg ! aacparse ! audio/mpeg, mpegversion=4 ! mux.
 ```
 
+Just video:
+
+```
+gst-launch-1.0 filesrc location=$SRC ! \
+    qtdemux name=demux \
+    demux.video_0 ! queue ! \
+    decodebin ! videoconvert ! x264enc bitrate=1000 tune=zerolatency ! video/x-h264 ! h264parse ! \
+    video/x-h264 ! queue ! flvmux name=mux ! \
+    rtmpsink location=$RTMP_DEST
+```
+
 ---
 
 Can we work out why a bad RTMP brings down the other mix?
@@ -168,6 +181,3 @@ gst-launch-1.0 \
     videoscale ! video/x-raw,width=320,height=180! \
     mix.
 ```
-
-
-

test_streams.md

@@ -6,12 +6,12 @@
 gst-launch-1.0 videotestsrc ! videoconvert ! autovideosink
 ```
 
-This should display the test pattern in a window, that looks a 
+This should display the test pattern in a window, that looks a
 bit like this:
 
 ![Test pattern window](images/test-pattern.png "Test pattern window")
 
-There are multiple test patterns available, such as
+There are multiple test patterns available, such as:
 
 | Pattern        | Example           |
 | ------------- |:-------------:|
@@ -23,6 +23,13 @@ There are multiple test patterns available, such as
 
 For the full list of patterns, see https://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-base-plugins/html/gst-plugins-base-plugins-videotestsrc.html
 
+### Change the shape of a test pattern
+
+To change the width and/or height, pass width and height immediately afterwards, e.g.
+
+```
+gst-launch-1.0 -v videotestsrc pattern=snow ! video/x-raw,width=1280,height=720 ! autovideosink
+```
 
 ### Listen to a test audio (beep)
 
@@ -30,6 +37,8 @@ For the full list of patterns, see https://gstreamer.freedesktop.org/data/doc/gs
 gst-launch-1.0 audiotestsrc ! audioconvert ! autoaudiosink
 ```
 
+### View test pattern and hear test audio
+
 Combine both the test pattern and test audio:
 
 ```