Updates to memory transfer, RTMP, and images

README.md

@@ -1,6 +1,6 @@
 # GStreamer command-line cheat sheet
 
-This series of docs provides a cheat sheet for Gstreamer on the command-line.
+This series of docs provides a cheat sheet for GStreamer on the command-line.
 
 ## Contents
 
@@ -8,8 +8,10 @@ This series of docs provides a cheat sheet for Gstreamer on the command-line.
 * [Basics](basics.md)
 * [RTMP](rtmp.md)
 * [Mixing video](mixing.md)
+* [Images](images.md)
 * [Capturing images](capturing_images.md)
 * [Sending/receiving video from shared memory](memory_transfer.md)
+* [Network transfer](network_transfer.md) (including how to send so that VLC can preview)
 
 ## Sources and references
 
@@ -18,10 +20,11 @@ This series of docs provides a cheat sheet for Gstreamer on the command-line.
 * [List of all Gstreamer plugins](https://gstreamer.freedesktop.org/documentation/plugins.html)
 * [Handy elements](https://gstreamer.freedesktop.org/documentation/tutorials/basic/handy-elements.html#uridecodebin)
 
-## Other cheat sheets
+## Other cheat-sheets
 
 * http://wiki.oz9aec.net/index.php/Gstreamer_cheat_sheet
 * https://github.com/xmementoit/gstreamerCheatsheet/blob/master/README.md
+* https://gist.github.com/nebgnahz/26a60cd28f671a8b7f522e80e75a9aa5
 
 ## Interaction
 
@@ -34,10 +37,10 @@ If you want to interact with GStreamer after it's started (e.g. respond to an ev
 
 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)
 
 # Problems or suggestions with this guide?
 
 If you spot anything incorrect or incomplete, reports are welcome, either using [issues](issues) or [pull requests](pulls)
-

images.md

@@ -0,0 +1,31 @@
+# Images (GStreamer command-line cheat sheet)
+
+Gstreamer can show images on video using the `imagefreeze` element.
+
+### Create a video from an image
+
+![Example imagefreeze single image](images/imagefreeze_single.png "Example imagefreeze single image")
+
+
+```
+export PIC="https://upload.wikimedia.org/wikipedia/en/thumb/8/80/Wikipedia-logo-v2.svg/263px-Wikipedia-logo-v2.svg.png"
+
+gst-launch-1.0 \
+    uridecodebin uri=$PIC ! \
+    imagefreeze ! \
+    autovideosink
+```
+
+### Create a video from multiple images
+
+Here's the same image four times, done with the help of `compsitor` (a mixer):
+
+```
+gst-launch-1.0 \
+    compositor name=m sink_1::xpos=263 sink_2::ypos=240 sink_3::xpos=263 sink_3::ypos=240 ! autovideosink \
+    uridecodebin uri=$PIC ! videoscale ! video/x-raw, width=263, height=240 ! imagefreeze ! m. \
+    uridecodebin uri=$PIC ! videoscale ! video/x-raw, width=263, height=240 ! imagefreeze ! m. \
+    uridecodebin uri=$PIC ! videoscale ! video/x-raw, width=263, height=240 ! imagefreeze ! m. \
+    uridecodebin uri=$PIC ! videoscale ! video/x-raw, width=263, height=240 ! imagefreeze ! m.
+```
+

memory_transfer.md

@@ -2,7 +2,7 @@
 
 The [`shmsink`](https://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-bad/html/gst-plugins-bad-plugins-shmsink.html) element allows you to write video into shared memory, from which another gstreamer application can read it with [`shmsrc`](https://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-bad/html/gst-plugins-bad-plugins-shmsrc.html).
 
-### Puttingn a stream into memory
+### Putting a stream into memory
 
 ```
 gst-launch-1.0 -v videotestsrc ! \

network_transfer.md

@@ -0,0 +1,163 @@
+# Transfer of audio/video via a network socket  (GStreamer command-line cheat sheet)
+
+GStreamer can send and receive audio and video via a network socket, using either UDP or TCP.
+
+*UDP* is faster but lossy - there is no attempt to resend lost network packets to it will fail if the network is not perfect. *TCP* acknowledges every network packet so is slower, but more reliable.
+
+## UDP
+
+### Audio via UDP
+
+To send an audio test source:
+
+```
+gst-launch-1.0 audiotestsrc ! avenc_ac3 ! mpegtsmux ! rtpmp2tpay ! udpsink host=127.0.0.1 port=7001
+```
+
+To send an audio 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 ! udpsink port=7001
+```
+
+And to receive audio:
+
+```
+gst-launch-1.0 udpsrc port=7001 ! decodebin ! autoaudiosink
+```
+
+### Video via UDP, as h264
+
+To send a test stream:
+
+```
+gst-launch-1.0 videotestsrc ! decodebin ! x264enc ! rtph264pay ! udpsink port=7001
+```
+
+Or to send a file (video or audio only, not both):
+
+```
+# Make sure $SRC is set to an video file (e.g. an MP4 file)
+gst-launch-1.0  filesrc location=$SRC ! decodebin ! x264enc ! rtph264pay ! udpsink port=7001
+```
+
+To receive:
+
+```
+gst-launch-1.0 \
+    udpsrc port=7001 caps = "application/x-rtp, media=(string)video, clock-rate=(int)90000, encoding-name=(string)H264, payload=(int)96" ! \
+    rtph264depay ! decodebin ! videoconvert ! autovideosink
+```
+
+### Video via UDP, as MPEG-2
+
+To send a video test source:
+
+```
+gst-launch-1.0 videotestsrc ! x264enc ! mpegtsmux ! rtpmp2tpay ! udpsink host=127.0.0.1 port=7001
+```
+
+To receive:
+
+```
+gst-launch-1.0 udpsrc port=7001 ! decodebin ! autovideosink
+```
+
+### Both video and audio
+
+To send both a video and audio test source (mixed together):
+
+```
+gst-launch-1.0 \
+    videotestsrc ! x264enc ! muxer.  audiotestsrc ! avenc_ac3 ! \
+    muxer.  mpegtsmux name=muxer ! rtpmp2tpay ! udpsink host=127.0.0.1 port=7001
+```
+
+And to receive both video and audio together:
+
+```
+gst-launch-1.0 \
+    udpsrc port=7001 caps="application/x-rtp" ! \
+    rtpmp2tdepay ! decodebin name=decoder ! autoaudiosink  decoder. ! autovideosink
+```
+
+## TCP
+
+### Send and receive audio via TCP
+
+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
+```
+
+And to receive:
+
+```
+gst-launch-1.0 tcpclientsrc port=7001 host=0.0.0.0 ! decodebin ! autoaudiosink
+```
+
+### Send and receive video via TCP
+
+Test video stream:
+
+```
+gst-launch-1.0 videotestsrc ! \
+    decodebin ! x264enc ! mpegtsmux ! queue ! \
+    tcpserversink port=7001 host=127.0.0.1 recover-policy=keyframe sync-method=latest-keyframe sync=false
+```
+
+MP4 file (video only):
+
+```
+gst-launch-1.0 \
+    filesrc location=$SRC ! decodebin ! x264enc ! mpegtsmux ! queue ! \
+    tcpserversink host=127.0.0.1 port=7001 recover-policy=keyframe sync-method=latest-keyframe sync=false
+```
+
+To receive, either use VLC (`tcp://localhost:7001`) or this command:
+
+```
+gst-launch-1.0 \
+    tcpclientsrc host=127.0.0.1 port=7001 ! \
+    decodebin ! videoconvert ! autovideosink sync=false
+```
+
+### Stream and receive video via TCP, using Matroska
+
+Should you wish to use the Matroska container rather than MPEG, here are some examples.
+(The [Matroska FAQ](https://www.matroska.org/technical/guides/faq/index.html) nicely describes what it is, if you're interested.)
+
+To send a test stream:
+
+```
+gst-launch-1.0 \
+    videotestsrc is-live=true ! \
+    queue ! videoconvert ! x264enc byte-stream=true ! \
+    h264parse config-interval=1 ! queue ! matroskamux ! queue leaky=2 ! \
+    tcpserversink port=7001 host=0.0.0.0 recover-policy=keyframe sync-method=latest-keyframe sync=false
+```
+
+To send a file (video only):
+
+```
+# Make sure $SRC is set to an video file (e.g. an MP4 file)
+gst-launch-1.0 \
+    filesrc location=$SRC ! decodebin ! \
+    queue ! videoconvert ! x264enc byte-stream=true ! \
+    h264parse config-interval=1 ! queue ! matroskamux ! queue leaky=2 ! \
+    tcpserversink port=7001 host=0.0.0.0 recover-policy=keyframe sync-method=latest-keyframe sync=false
+```
+
+To receive:
+
+```
+gst-launch-1.0 \
+    tcpclientsrc host=0.0.0.0 port=7001 typefind=true do-timestamp=false ! \
+    matroskademux ! typefind ! avdec_h264 ! autovideosink
+```
+
+I struggle to get VLC to play this (through `tcp://localhost:7001`).

rtmp.md

@@ -96,6 +96,7 @@ gst-launch-1.0 \
 This overlays an RTMP source as a picture-in-picture on top of a local filesource (set as `$SRC`)
 
 ```
+export QUEUE="queue max-size-time=0 max-size-bytes=0 max-size-buffers=0"
 gst-launch-1.0 \
     filesrc location="$SRC" ! \
     decodebin ! videoconvert ! \
@@ -111,7 +112,6 @@ gst-launch-1.0 \
     mix.
 ```
 
-
 ## Sending to an RTMP server
 
 ### Sending a test stream to an RTMP server
@@ -147,3 +147,27 @@ gst-launch-1.0 filesrc location=$SRC ! \
     audio/x-raw,rate=48000 ! \
     voaacenc bitrate=96000 ! audio/mpeg ! aacparse ! audio/mpeg, mpegversion=4 ! mux.
 ```
+
+---
+
+Can we work out why a bad RTMP brings down the other mix?
+
+```
+export QUEUE="queue max-size-time=0 max-size-bytes=0 max-size-buffers=0"
+gst-launch-1.0 \
+    filesrc location="$SRC2" ! \
+    decodebin ! videoconvert ! \
+    videoscale ! video/x-raw,width=640,height=360 ! \
+    compositor name=mix sink_0::alpha=1 sink_1::alpha=1 sink_1::xpos=50 sink_1::ypos=50 !   \
+    videoconvert ! autovideosink \
+    rtmpsrc location="$RTMP_DEST" ! \
+    flvdemux name=demux \
+    demux.audio ! $QUEUE ! decodebin ! fakesink \
+    demux.video ! $QUEUE ! decodebin ! \
+    videoconvert ! \
+    videoscale ! video/x-raw,width=320,height=180! \
+    mix.
+```
+
+
+