GstMessageType

The different message types that are available.

Values

ValueMeaning
Unknown0

an undefined message

Eos1

end-of-stream reached in a pipeline. The application will only receive this message in the PLAYING state and every time it sets a pipeline to PLAYING that is in the EOS state. The application can perform a flushing seek in the pipeline, which will undo the EOS state again.

Error2

an error occurred. When the application receives an error message it should stop playback of the pipeline and not assume that more data will be played. It is possible to specify a redirection url to the error messages by setting a redirect-location field into the error message, application or high level bins might use the information as required.

Warning4

a warning occurred.

Info8

an info message occurred

Tag16

a tag was found.

Buffering32

the pipeline is buffering. When the application receives a buffering message in the PLAYING state for a non-live pipeline it must PAUSE the pipeline until the buffering completes, when the percentage field in the message is 100%. For live pipelines, no action must be performed and the buffering percentage can be used to inform the user about the progress.

StateChanged64

a state change happened

StateDirty128

an element changed state in a streaming thread. This message is deprecated.

StepDone256

a stepping operation finished.

ClockProvide512

an element notifies its capability of providing a clock. This message is used internally and never forwarded to the application.

ClockLost1024

The current clock as selected by the pipeline became unusable. The pipeline will select a new clock on the next PLAYING state change. The application should set the pipeline to PAUSED and back to PLAYING when this message is received.

NewClock2048

a new clock was selected in the pipeline.

StructureChange4096

the structure of the pipeline changed. This message is used internally and never forwarded to the application.

StreamStatus8192

status about a stream, emitted when it starts, stops, errors, etc..

Application16384

message posted by the application, possibly via an application-specific element.

Element32768

element-specific message, see the specific element's documentation

SegmentStart65536

pipeline started playback of a segment. This message is used internally and never forwarded to the application.

SegmentDone131072

pipeline completed playback of a segment. This message is forwarded to the application after all elements that posted @GST_MESSAGE_SEGMENT_START posted a GST_MESSAGE_SEGMENT_DONE message.

DurationChanged262144

The duration of a pipeline changed. The application can get the new duration with a duration query.

Latency524288

Posted by elements when their latency changes. The application should recalculate and distribute a new latency.

AsyncStart1048576

Posted by elements when they start an ASYNC #GstStateChange. This message is not forwarded to the application but is used internally.

AsyncDone2097152

Posted by elements when they complete an ASYNC #GstStateChange. The application will only receive this message from the toplevel pipeline.

RequestState4194304

Posted by elements when they want the pipeline to change state. This message is a suggestion to the application which can decide to perform the state change on (part of) the pipeline.

StepStart8388608

A stepping operation was started.

Qos16777216

A buffer was dropped or an element changed its processing strategy for Quality of Service reasons.

Progress33554432

A progress message.

Toc67108864

A new table of contents (TOC) was found or previously found TOC was updated.

ResetTime134217728

Message to request resetting the pipeline's running time from the pipeline. This is an internal message which applications will likely never receive.

StreamStart268435456

Message indicating start of a new stream. Useful e.g. when using playbin in gapless playback mode, to get notified when the next title actually starts playing (which will be some time after the URI for the next title has been set).

NeedContext536870912

Message indicating that an element wants a specific context (Since: 1.2)

HaveContext1073741824

Message indicating that an element created a context (Since: 1.2)

Extended2147483648

Message is an extended message type (see below). These extended message IDs can't be used directly with mask-based API like gst.bus.Bus.poll or gst.bus.Bus.timedPopFiltered, but you can still filter for GST_MESSAGE_EXTENDED and then check the result for the specific type. (Since: 1.4)

DeviceAdded2147483649

Message indicating a #GstDevice was added to a #GstDeviceProvider (Since: 1.4)

DeviceRemoved2147483650

Message indicating a #GstDevice was removed from a #GstDeviceProvider (Since: 1.4)

PropertyNotify2147483651

Message indicating a #GObject property has changed (Since: 1.10)

StreamCollection2147483652

Message indicating a new #GstStreamCollection is available (Since: 1.10)

StreamsSelected2147483653

Message indicating the active selection of #GstStreams has changed (Since: 1.10)

Redirect2147483654

Message indicating to request the application to try to play the given URL(s). Useful if for example a HTTP 302/303 response is received with a non-HTTP URL inside. (Since: 1.10)

DeviceChanged2147483655

Message indicating a #GstDevice was changed a #GstDeviceProvider (Since: 1.16)

InstantRateRequest2147483656

Message sent by elements to request the running time from the pipeline when an instant rate change should be applied (which may be in the past when the answer arrives). (Since: 1.18)

Any4294967295

mask for all of the above messages.