mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-11-20 00:31:13 +00:00
c73b03243a
Original commit message from CVS: * docs/design/part-messages.txt: update info * docs/gst/tmpl/.cvsignore: * docs/gst/tmpl/gstcaps.sgml: * docs/gst/tmpl/gstclock.sgml: * gst/gstbus.c: * gst/gstcaps.c: * gst/gstcaps.h: * gst/gstclock.c: * gst/gstclock.h: * gst/gstmessage.c: added descriptions for bus and message inline caps and clock docs
75 lines
2.1 KiB
Text
75 lines
2.1 KiB
Text
Messages
|
|
--------
|
|
|
|
Messages are refcounted lightweight objects to signal the application
|
|
of pipeline events.
|
|
|
|
Messages are implemented as a subclass of GstMiniObject with a generic
|
|
GstStructure as the content. This allows for writing custom messages without
|
|
requiring an API change while allowing a wide range of different types
|
|
of messages.
|
|
|
|
Messages are posted by objects in the pipeline and are passed to the
|
|
application using the GstBus.
|
|
|
|
|
|
Message types
|
|
-------------
|
|
|
|
GST_MESSAGE_EOS:
|
|
|
|
The pipeline went to EOS. This means that all the sink elements in the
|
|
pipeline posted the EOS message to the bus.
|
|
|
|
GST_MESSAGE_ERROR:
|
|
|
|
An element in the pipeline got into an error state. The message carries
|
|
a GError and a debug string describing the error. This usually means that
|
|
part of the pipeline is not streaming anymore.
|
|
|
|
GST_MESSAGE_WARNING:
|
|
|
|
An element in the pipeline encountered a condition that made it produce a
|
|
warning. This could be a recoverable decoding error or some other non fatal
|
|
event. The pipeline continues streaming after a warning.
|
|
|
|
GST_MESSAGE_INFO:
|
|
|
|
An element produced an informational message.
|
|
|
|
GST_MESSAGE_TAG:
|
|
|
|
An element decoded metadata about the stream. The message carries a GstTagList
|
|
with the tag information.
|
|
|
|
GST_MESSAGE_BUFFERING:
|
|
|
|
An element is buffering data and that could potentially take some time.
|
|
|
|
GST_MESSAGE_STATE_CHANGED:
|
|
|
|
An element changed state in the pipeline. The message carries the old an new
|
|
state of the element.
|
|
|
|
GST_MESSAGE_STEP_DONE:
|
|
|
|
An element stepping frames has finished.
|
|
|
|
GST_MESSAGE_NEW_CLOCK:
|
|
|
|
A new clock was selected for the pipeline.
|
|
|
|
GST_MESSAGE_STRUCTURE_CHANGE:
|
|
|
|
The pipeline changed of structure, This means elements were added or removed or
|
|
pads were linked or unlinked.
|
|
|
|
GST_MESSAGE_STREAM_STATUS:
|
|
|
|
An element posted information about the stream it is handling. This could include
|
|
information about the length of the stream.
|
|
|
|
GST_MESSAGE_APPLICATION:
|
|
|
|
An element posted an application specific message.
|
|
|