The goal of the GstPlay library is to ease the integration of multimedia
playback features in applications. Thus, if you need to build a media player
from the ground-up, GstPlay provides the features you will most likely need.
An example player is available in gst-examples/playback/player/gst-play/.
Internally the GstPlay makes use of the `playbin3` element. The legacy
`playbin2` can be selected if the `GST_PLAY_USE_PLAYBIN3=0` environment
variable has been set.
**Important note**: If your application relies on the GstBus to get
notifications from GstPlay, you need to add some explicit clean-up code in
order to prevent the GstPlay object from leaking. See below for the details.
If you use the GstPlaySignalAdapter, no special clean-up is required.
When the GstPlaySignalAdapter is not used, the GstBus owned by GstPlay should
be set to flushing state before any attempt to drop the last reference of the
GstPlay object. An example in C:
```c
...
GstBus *bus = gst_play_get_message_bus (player);
gst_bus_set_flushing (bus, TRUE);
gst_object_unref (bus);
gst_object_unref (player);
```
The messages managed by the player contain a reference to itself, and if the
bus watch is just removed together with dropping the player then the bus will
simply keep them around forever (and the bus never goes away because the
player has a strong reference to it, so there's a reference cycle as long as
there are messages). Setting the bus to flushing state forces it to get rid
of its queued messages, thus breaking any possible reference cycle.
Creates a new #GstPlay instance.
Video is going to be rendered by @video_renderer, or if %NULL is provided
no special video set up will be done and some default handling will be
performed.
a new #GstPlay instance
GstPlayVideoRenderer to use
%TRUE if pipeline dumps are included in #GstPlay error message
details.
a #GstPlay configuration
current position update interval in milliseconds
a #GstPlay configuration
%TRUE if accurate seeking is enabled
a #GstPlay configuration
Return the user agent which has been configured using
gst_play_config_set_user_agent() if any.
the configured agent, or %NULL
a #GstPlay configuration
When enabled, the error message emitted by #GstPlay will include a pipeline
dump (in Graphviz DOT format) in the error details #GstStructure. The field
name is `pipeline-dump`.
This option is disabled by default.
a #GstPlay configuration
Include pipeline dumps in error details, or not.
Set desired interval in milliseconds between two position-updated messages.
Pass 0 to stop updating the position.
a #GstPlay configuration
interval in ms
Enable or disable accurate seeking. When enabled, elements will try harder
to seek as accurately as possible to the requested seek position. Generally
it will be slower especially for formats that don't have any indexes or
timestamp markers in the stream.
If accurate seeking is disabled, elements will seek as close as the request
position without slowing down seeking too much.
Accurate seeking is disabled by default.
a #GstPlay configuration
accurate seek or not
Set the user agent to pass to the server if @play needs to connect
to a server during playback. This is typically used when playing HTTP
or RTSP streams.
a #GstPlay configuration
the string to use as user agent
A #GList of
matching #GstPlayAudioInfo.
a #GstPlayMediaInfo
A #GList of
matching #GstPlaySubtitleInfo.
a #GstPlayMediaInfo
A #GList of
matching #GstPlayVideoInfo.
a #GstPlayMediaInfo
A #gboolean indicating whether the passed message represents a #GstPlay message or not.
A #GstMessage
Frees a %NULL terminated array of #GstPlayVisualization.
a %NULL terminated array of #GstPlayVisualization to free
a %NULL terminated array containing all available
visualizations. Use gst_play_visualizations_free() after
usage.
Retrieve the current value of audio-video-offset property
The current value of audio-video-offset in nanoseconds
#GstPlay instance
Retrieve the current value of the indicated @type.
The current value of @type, between [0,1]. In case of
error -1 is returned.
#GstPlay instance
#GstPlayColorBalanceType
Get a copy of the current configuration of the play. This configuration
can either be modified and used for the gst_play_set_config() call
or it must be freed after usage.
a copy of the current configuration of @play. Use
gst_structure_free() after usage or gst_play_set_config().
#GstPlay instance
A Function to get current audio #GstPlayAudioInfo instance.
current audio track.
The caller should free it with g_object_unref()
#GstPlay instance
A Function to get current subtitle #GstPlaySubtitleInfo instance.
current subtitle track.
The caller should free it with g_object_unref()
#GstPlay instance
A Function to get current video #GstPlayVideoInfo instance.
current video track.
The caller should free it with g_object_unref()
#GstPlay instance
Name of the currently enabled
visualization.
g_free() after usage.
#GstPlay instance
Retrieves the duration of the media stream that self represents.
the duration of the currently-playing media stream, in
nanoseconds.
#GstPlay instance
A Function to get the current media info #GstPlayMediaInfo instance.
media info instance.
The caller should free it with g_object_unref()
#GstPlay instance
GstPlay API exposes a #GstBus instance which purpose is to provide data
structures representing play-internal events in form of #GstMessage<!-- -->s of
type GST_MESSAGE_APPLICATION.
Each message carries a "play-message" field of type #GstPlayMessage.
Further fields of the message data are specific to each possible value of
that enumeration.
Applications can consume the messages asynchronously within their own
event-loop / UI-thread etc. Note that in case the application does not
consume the messages, the bus will accumulate these internally and eventually
fill memory. To avoid that, the bus has to be set "flushing".
The play message bus instance
#GstPlay instance
Retrieve the current value of the indicated @type.
The current value of @type, Default: 0x00000000 "none
#GstPlay instance
Retrieve the current value of the indicated @type.
The current value of @type, Default: -1 "none"
#GstPlay instance
%TRUE if the currently-playing stream is muted.
#GstPlay instance
The internal playbin instance.
The caller should free it with g_object_unref()
#GstPlay instance
the absolute position time, in nanoseconds, of the
currently-playing stream.
#GstPlay instance
current playback rate
#GstPlay instance
Current subtitle URI
URI of the current external subtitle.
g_free() after usage.
#GstPlay instance
Retrieve the current value of subtitle-video-offset property
The current value of subtitle-video-offset in nanoseconds
#GstPlay instance
Gets the URI of the currently-playing stream.
a string containing the URI of the
currently-playing stream. g_free() after usage.
#GstPlay instance
Get a snapshot of the currently selected video stream, if any. The format can be
selected with @format and optional configuration is possible with @config.
Currently supported settings are:
- width, height of type G_TYPE_INT
- pixel-aspect-ratio of type GST_TYPE_FRACTION
Except for GST_PLAY_THUMBNAIL_RAW_NATIVE format, if no config is set, pixel-aspect-ratio would be 1/1
Current video snapshot sample or %NULL on failure
#GstPlay instance
output format of the video snapshot
Additional configuration
Returns the current volume level, as a percentage between 0 and 1.
the volume as percentage between 0 and 1.
#GstPlay instance
Checks whether the @play has color balance support available.
%TRUE if @play has color balance support. Otherwise,
%FALSE.
#GstPlay instance
Pauses the current stream.
#GstPlay instance
Request to play the loaded stream.
#GstPlay instance
Seeks the currently-playing stream to the absolute @position time
in nanoseconds.
#GstPlay instance
position to seek in nanoseconds
%TRUE or %FALSE
Sets the audio track @stream_index.
#GstPlay instance
stream index
Enable or disable the current audio track.
#GstPlay instance
TRUE or FALSE
Sets audio-video-offset property by value of @offset
#GstPlay instance
#gint64 in nanoseconds
Sets the current value of the indicated channel @type to the passed
value.
#GstPlay instance
#GstPlayColorBalanceType
The new value for the @type, ranged [0,1]
Set the configuration of the play. If the play is already configured, and
the configuration hasn't changed, this function will return %TRUE. If the
play is not in the GST_PLAY_STATE_STOPPED, this method will return %FALSE
and active configuration will remain.
@config is a #GstStructure that contains the configuration parameters for
the play.
This function takes ownership of @config.
%TRUE when the configuration could be set.
#GstPlay instance
a #GstStructure
Sets the current value of the indicated mode @type to the passed
value.
#GstPlay instance
The new value for the @type
Sets the current value of the indicated mode @type to the passed
value.
#GstPlay instance
The new value for the @type
%TRUE if the currently-playing stream should be muted.
#GstPlay instance
Mute state the should be set
Playback at specified rate
#GstPlay instance
playback rate
%TRUE or %FALSE
Sets the subtitle stack @stream_index.
#GstPlay instance
stream index
Enable or disable the current subtitle track.
#GstPlay instance
TRUE or FALSE
Sets the external subtitle URI. This should be combined with a call to
gst_play_set_subtitle_track_enabled(@play, TRUE) so the subtitles are actually
rendered.
#GstPlay instance
subtitle URI
Sets subtitle-video-offset property by value of @offset
#GstPlay instance
#gint64 in nanoseconds
Sets the next URI to play.
#GstPlay instance
next URI to play.
%TRUE or %FALSE
Sets the video track @stream_index.
#GstPlay instance
stream index
Enable or disable the current video track.
#GstPlay instance
TRUE or FALSE
%TRUE if the visualization was set correctly. Otherwise,
%FALSE.
#GstPlay instance
visualization element obtained from
#gst_play_visualizations_get()
Enable or disable the visualization.
#GstPlay instance
TRUE or FALSE
Sets the volume level of the stream as a percentage between 0 and 1.
#GstPlay instance
the new volume level, as a percentage between 0 and 1
Stops playing the current stream and resets to the first position
in the stream.
#GstPlay instance
#GstPlayStreamInfo specific to audio streams.
the audio bitrate in #GstPlayAudioInfo or -1 if unknown.
a #GstPlayAudioInfo
the number of audio channels in #GstPlayAudioInfo or 0 if unknown.
a #GstPlayAudioInfo
the language of the stream, or %NULL if unknown.
a #GstPlayAudioInfo
the audio maximum bitrate in #GstPlayAudioInfo or -1 if unknown.
a #GstPlayAudioInfo
the audio sample rate in #GstPlayAudioInfo or 0 if unknown.
a #GstPlayAudioInfo
hue or color balance.
brightness or black level.
color saturation or chroma
gain.
contrast or luma gain.
Gets a string representing the given color balance type.
a string with the name of the color
balance type.
a #GstPlayColorBalanceType
generic error.
Gets a string representing the given error.
a string with the given error.
a #GstPlayError
Structure containing the media information of a URI.
A #GList of
matching #GstPlayAudioInfo.
a #GstPlayMediaInfo
the container format or %NULL if unknown.
a #GstPlayMediaInfo
duration of the media.
a #GstPlayMediaInfo
Function to get the image (or preview-image) stored in taglist.
Application can use `gst_sample_*_()` API's to get caps, buffer etc.
GstSample or %NULL.
a #GstPlayMediaInfo
number of audio streams.
a #GstPlayMediaInfo
number of total streams.
a #GstPlayMediaInfo
number of subtitle streams.
a #GstPlayMediaInfo
number of video streams.
a #GstPlayMediaInfo
A #GList of
matching #GstPlayStreamInfo.
a #GstPlayMediaInfo
A #GList of
matching #GstPlaySubtitleInfo.
a #GstPlayMediaInfo
the tags contained in media info.
a #GstPlayMediaInfo
the media title or %NULL if unknown.
a #GstPlayMediaInfo
the URI associated with #GstPlayMediaInfo.
a #GstPlayMediaInfo
A #GList of
matching #GstPlayVideoInfo.
a #GstPlayMediaInfo
%TRUE if the media is live.
a #GstPlayMediaInfo
%TRUE if the media is seekable.
a #GstPlayMediaInfo
Types of messages that will be posted on the play API bus.
See also #gst_play_get_message_bus()
Source element was initalized for set URI
Sink position changed
Duration of stream changed
State changed, see #GstPlayState
Pipeline is in buffering state, message contains the percentage value of the decoding buffer
Sink has received EOS
Message contains an error
Message contains an error
Video sink received format in different dimensions than before
A media-info property has changed, message contains current #GstPlayMediaInfo
The volume of the audio ouput has changed
Audio muting flag has been toggled
Any pending seeking operation has been completed
a string with the name of the message.
a #GstPlayMessage
Parse the given buffering-percent @msg and extract the corresponding value
A #GstMessage
the resulting buffering percent
Parse the given duration @msg and extract the corresponding #GstClockTime
A #GstMessage
the resulting duration
Parse the given error @msg and extract the corresponding #GError
A #GstMessage
the resulting error
A #GstStructure containing additional details about the error
Parse the given @msg and extract the corresponding media information
A #GstMessage
the resulting media info
Parse the given @msg and extract the corresponding audio muted state
A #GstMessage
the resulting audio muted state
Parse the given position @msg and extract the corresponding #GstClockTime
A #GstMessage
the resulting position
Parse the given state @msg and extract the corresponding #GstPlayState
A #GstMessage
the resulting play state
Parse the given @msg and extract its #GstPlayMessage type.
A #GstMessage
the resulting message type
Parse the given @msg and extract the corresponding video dimensions
A #GstMessage
the resulting video width
the resulting video height
Parse the given @msg and extract the corresponding audio volume
A #GstMessage
the resulting audio volume
Parse the given error @msg and extract the corresponding #GError warning
A #GstMessage
the resulting warning
A #GstStructure containing additional details about the warning
A bus-watching #GSource will be created and attached to the the
thread-default #GMainContext. The attached callback will emit the
corresponding signal for the message received. Matching signals for play
messages from the bus will be emitted by it on the created adapter object.
A new #GstPlaySignalAdapter to connect signal handlers to.
#GstPlay instance to emit signals for.
Create an adapter that synchronously emits its signals, from the thread in
which the messages have been posted.
A new #GstPlaySignalAdapter to connect signal handlers to.
#GstPlay instance to emit signals for.
A bus-watching #GSource will be created and attached to the @context. The
attached callback will emit the corresponding signal for the message
received. Matching signals for play messages from the bus will be emitted by
it on the created adapter object.
A new #GstPlaySignalAdapter to connect signal handlers to.
#GstPlay instance to emit signals for.
A #GMainContext on which the main-loop will process play bus messages on.
The #GstPlay owning this signal adapter.
#GstPlaySignalAdapter instance
Emitted on errors.
The error
Additional error details
Emitted on warnings.
The warning
Additional warning details
raw native format.
raw xRGB format.
raw BGRx format.
jpeg format.
png format.
the play is stopped.
the play is buffering.
the play is paused.
the play is currently playing a
stream.
Gets a string representing the given state.
a string with the name of the state.
a #GstPlayState
Base structure for information concerning a media stream. Depending on
the stream type, one can find more media-specific information in
#GstPlayVideoInfo, #GstPlayAudioInfo, #GstPlaySubtitleInfo.
the #GstCaps of the stream or %NULL if
unknown.
a #GstPlayStreamInfo
A string describing codec used in #GstPlayStreamInfo.
codec string or %NULL on unknown.
a #GstPlayStreamInfo
Function to get stream index from #GstPlayStreamInfo instance or -1 if
unknown.
the stream index of this stream.
a #GstPlayStreamInfo
Function to return human readable name for the stream type
of the given @info (ex: "audio", "video", "subtitle")
a human readable name
a #GstPlayStreamInfo
the tags contained in this stream.
a #GstPlayStreamInfo
#GstPlayStreamInfo specific to subtitle streams.
the language of the stream, or %NULL if unknown.
a #GstPlaySubtitleInfo
#GstPlayStreamInfo specific to video streams.
the current bitrate of video in #GstPlayVideoInfo or -1 if unknown.
a #GstPlayVideoInfo
a #GstPlayVideoInfo
Numerator of frame rate
Denominator of frame rate
the height of video in #GstPlayVideoInfo or -1 if unknown.
a #GstPlayVideoInfo
the maximum bitrate of video in #GstPlayVideoInfo or -1 if unknown.
a #GstPlayVideoInfo
Returns the pixel aspect ratio in @par_n and @par_d
a #GstPlayVideoInfo
numerator
denominator
the width of video in #GstPlayVideoInfo or -1 if unknown.
a #GstPlayVideoInfo
Window handle to use or %NULL
Window handle to use or %NULL
the custom video_sink element to be set for the video renderer
Tell an overlay that it has been exposed. This will redraw the current frame
in the drawable even if the pipeline is PAUSED.
a #GstPlayVideoOverlayVideoRenderer instance.
Return the currently configured render rectangle. See gst_play_video_overlay_video_renderer_set_render_rectangle()
for details.
a #GstPlayVideoOverlayVideoRenderer instance
the horizontal offset of the render area inside the window
the vertical offset of the render area inside the window
the width of the render area inside the window
the height of the render area inside the window
The currently set, platform specific window
handle
#GstPlayVideoRenderer instance
Configure a subregion as a video target within the window set by
gst_play_video_overlay_video_renderer_set_window_handle(). If this is not
used or not supported the video will fill the area of the window set as the
overlay to 100%. By specifying the rectangle, the video can be overlaid to
a specific region of that window only. After setting the new rectangle one
should call gst_play_video_overlay_video_renderer_expose() to force a
redraw. To unset the region pass -1 for the @width and @height parameters.
This method is needed for non fullscreen video overlay in UI toolkits that
do not support subwindows.
a #GstPlayVideoOverlayVideoRenderer instance
the horizontal offset of the render area inside the window
the vertical offset of the render area inside the window
the width of the render area inside the window
the height of the render area inside the window
Sets the platform specific window handle into which the video
should be rendered
#GstPlayVideoRenderer instance
handle referencing to the platform specific window
A #GstPlayVisualization descriptor.
name of the visualization.
description of the visualization.
Makes a copy of the #GstPlayVisualization. The result must be
freed using gst_play_visualization_free().
an allocated copy of @vis.
#GstPlayVisualization instance
Frees a #GstPlayVisualization.
#GstPlayVisualization instance
Gets a string representing the given color balance type.
a string with the name of the color
balance type.
a #GstPlayColorBalanceType
Gets a string representing the given error.
a string with the given error.
a #GstPlayError
a string with the name of the message.
a #GstPlayMessage
Parse the given buffering-percent @msg and extract the corresponding value
A #GstMessage
the resulting buffering percent
Parse the given duration @msg and extract the corresponding #GstClockTime
A #GstMessage
the resulting duration
Parse the given error @msg and extract the corresponding #GError
A #GstMessage
the resulting error
A #GstStructure containing additional details about the error
Parse the given @msg and extract the corresponding media information
A #GstMessage
the resulting media info
Parse the given @msg and extract the corresponding audio muted state
A #GstMessage
the resulting audio muted state
Parse the given position @msg and extract the corresponding #GstClockTime
A #GstMessage
the resulting position
Parse the given state @msg and extract the corresponding #GstPlayState
A #GstMessage
the resulting play state
Parse the given @msg and extract its #GstPlayMessage type.
A #GstMessage
the resulting message type
Parse the given @msg and extract the corresponding video dimensions
A #GstMessage
the resulting video width
the resulting video height
Parse the given @msg and extract the corresponding audio volume
A #GstMessage
the resulting audio volume
Parse the given error @msg and extract the corresponding #GError warning
A #GstMessage
the resulting warning
A #GstStructure containing additional details about the warning
Gets a string representing the given state.
a string with the name of the state.
a #GstPlayState