GStreamer has a debugging feature that automatically generates pipeline graphs.
* https://gstreamer.freedesktop.org/documentation/tutorials/basic/debugging-tools.html
-### Using $GST_DEBUG_DUMP_DOT_DIR
+* Table of Contents
+ * [Displaying debug messages with $GST_DEBUG](#displaying-debug-messages-with-$gst_debug)
+ * [Generating pipeline graph with $GST_DEBUG_DUMP_DOT_DIR](#generating-pipeline-graph-with-$gst_debug_dump_dot_dir)
+ * [Debugging remotely with gst-debugger](#debugging-remotely-with-gst-debugger)
+
+
+### Displaying debug messages with $GST_DEBUG
+
+If GStreamer has been configured with --enable-gst-debug=yes, this variable can be set to a list of debug options, which cause GStreamer to print out different types of debugging information to stderr. The variable takes a comma-separated list of "category_name:level" pairs to set specific levels for the individual categories. The level value ranges from 0 (nothing) to 9 (MEMDUMP).
+For more details, refer to https://gstreamer.freedesktop.org/documentation/tutorials/basic/debugging-tools.html
+
+* 1 (ERROR): Logs all fatal errors.
+* 2 (WARNING): Logs all warnings.
+* 3 (FIXME): Logs all fixme messages.
+* 4 (INFO): Logs all informational messages.
+* 5 (DEBUG): Logs all debug messages.
+* 6 (LOG): Logs all log messages.
+* 7 (TRACE): Logs all trace messages.
+* 9 (MEMDUMP): Log all memory dump messages.
+
+#### How to use debug options
+The category_name can contain "*" as a wildcard. For example, setting GST_DEBUG to GST_AUTOPLUG:6,GST_ELEMENT_*:4, will cause the GST_AUTOPLUG category to be logged at full LOG level, while all categories starting with GST_ELEMENT_ will be logged at INFO level. To get all possible debug output, set GST_DEBUG to *:9. For debugging purposes a *:6 debug log is usually the most useful, as it contains all important information, but hides a lot of noise such as refs/unrefs. For bug reporting purposes, a *:6 log is also what will be requested usually. It's often also worth running with *:3 to see if there are any non-fatal errors or warnings that might be related to the problem at hand. Since GStreamer 1.2 it is also possible to specify debug levels by name, e.g. GST_DEBUG=*:WARNING,*audio*:LOG
+```bash
+$ export GST_DEBUG=[Level]
+```
+
+Use gst-launch-1.0 --gst-debug-help to obtain the list of all registered categories.
+```bash
+$ gst-launch-1.0 --gst-debug-help
+```
+
+#### Case study: Tracing Gstreamer plugins with GST_DEBUG
+Traces for buffer flow, events and messages in TRACE level.
+```bash
+$ GST_DEBUG="GST_TRACER:7,GST_BUFFER*:7,GST_EVENT:7,GST_MESSAGE:7" \
+GST_TRACERS=log gst-launch-1.0 fakesrc num-buffers=10 ! fakesink -
+```
+
+Print some pipeline stats on exit.
+```bash
+$ GST_DEBUG="GST_TRACER:7" GST_TRACERS="stats;rusage" \
+GST_DEBUG_FILE=trace.log gst-launch-1.0 fakesrc num-buffers=10 \
+sizetype=fixed ! queue ! fakesink && gst-stats-1.0 trace.log
+```
+
+Get ts, average-cpuload, current-cpuload, time, and plot.
+* https://github.com/GStreamer/gstreamer/blob/master/scripts/gst-plot-traces.sh
+```bash
+$ GST_DEBUG="GST_TRACER:7" GST_TRACERS="stats;rusage" \
+GST_DEBUG_FILE=trace.log /usr/bin/gst-play-1.0 ./your_movie.mp4 && \
+./scripts/gst-plot-traces.sh --format=png | gnuplot eog trace.log.*.png
+```
+
+Print processing latencies.
+```bash
+$ GST_DEBUG="GST_TRACER:7" GST_TRACERS=latency gst-launch-1.0 \
+audiotestsrc num-buffers=10 ! audioconvert ! volume volume=0.7 ! autoaudiosink
+```
+
+Raise a warning if a leak is detected.
+```bash
+$ GST_TRACERS="leaks" gst-launch-1.0 videotestsrc num-buffers=10 ! fakesink
+```
+
+Check if any GstEvent or GstMessage is leaked and raise a warning.
+```bash
+$ GST_DEBUG="GST_TRACER:7" GST_TRACERS="leaks(GstEvent,GstMessage)" \
+gst-launch-1.0 videotestsrc num-buffers=10 ! fakesink
+```
+
+### Generating pipeline graph with $GST_DEBUG_DUMP_DOT_DIR
Regardless of whether you are using gst-launch-1.0 or a GStreamer application, you have to need to define the GST_DEBUG_DUMP_DOT_DIR environment variable.
GStreamer uses this environment variable as the output location to generate pipeline graphs.
0.00.02.007860000-gst-launch.PAUSED_PLAYING.dot
0.00.05.095596000-gst-launch.PLAYING_PAUSED.dot
0.00.05.104625000-gst-launch.PAUSED_READY.dot
+```
+
+#### How to convert a pipeling dot file to pdf
+
+XDot is an interactive viewer for graphs written in Graphviz's dot language. You can view the pipeline graph graphically with XDot.
+```bash
+$ sudo apt install xdot
$ xdot 0.00.00.328088000-gst-launch.NULL_READY.dot
```
+<img src=gst-debug-dump-dot-dir-xot.png border=0></img>
+
+
+If you want to get a PDF format file from .dot file, You need to convert the to a graphical format with dot command.
+The below exampe shows how to render PAUSED_READY.dot pipeline.
+```bash
+* Case 1: Convert .dot to .pdf
+$ dot -Tpdf 0.00.05.104625000-gst-launch.PAUSED_READY.dot > pipeline_PAUSED_READY.pdf
+$ evince pipeline_PaUSED_READY.pdf
+* Case 2: Convert .dot to .png
+$ dot -Tpng 0.00.05.104625000-gst-launch.PAUSED_READY.dot > pipeline_PAUSED_READY.png
+$ eog pipeline_PaUSED_READY.png
+```
-#### Case study: NNstreamer's test case
+#### Case study: Test case in NNstreamer
First of all, try to build NNStreamer source code with cmake in nnstreamer/build folder.
And then, you can see elements and caps graph in a pipeline.
-### gst-debugger
+### Debugging remotely with gst-debugger
gst-debugger (a.k.a Gstreamer Debugger) toolset allows to introspect gst-pipeline remotely. It provides graphical client, and GStreamer's plugin.
This guide is written on Ubuntu 16.04 X86_64 distribution.
projects / platform / upstream / nnstreamer.git / commitdiff
