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The Discoverer is a utility object which allows to get as much
information as possible from one or many URIs.
It provides two APIs, allowing usage in blocking or non-blocking mode.
The blocking mode just requires calling DiscovererExt::discover_uri
with the URI one wishes to discover.
The non-blocking mode requires a running glib::MainLoop iterating a
glib::MainContext, where one connects to the various signals, appends the
URIs to be processed (through DiscovererExt::discover_uri_async) and then
asks for the discovery to begin (through DiscovererExt::start).
By default this will use the GLib default main context unless you have
set a custom context using glib::MainContext::push_thread_default.
All the information is returned in a DiscovererInfo structure.
Implements
DiscovererExt, glib::object::ObjectExt
Trait containing all Discoverer methods.
Implementors
Creates a new Discoverer with the provided timeout.
timeout
timeout per file, in nanoseconds. Allowed are values between
one second (GST_SECOND) and one hour (3600 * GST_SECOND)
Returns
The new Discoverer.
If an error occurred when creating the discoverer, err will be set
accordingly and None will be returned. If err is set, the caller must
free it when no longer needed using glib::Error::free.
Synchronously discovers the given uri.
A copy of uri will be made internally, so the caller can safely g_free
afterwards.
uri
The URI to run on.
Returns
the result of the scanning. Can be None if an
error occurred.
Appends the given uri to the list of URIs to discoverer. The actual
discovery of the uri will only take place if DiscovererExt::start has
been called.
A copy of uri will be made internally, so the caller can safely g_free
afterwards.
uri
the URI to add.
Returns
true if the uri was successfully appended to the list of pending
uris, else false
Allow asynchronous discovering of URIs to take place.
A glib::MainLoop must be available for Discoverer to properly work in
asynchronous mode.
Stop the discovery of any pending URIs and clears the list of pending URIS (if any).
Will be emitted in async mode when all information on a URI could be discovered, or an error occurred.
When an error occurs, info might still contain some partial information,
depending on the circumstances of the error.
info
the results DiscovererInfo
error
glib::Error, which will be non-NULL if an error
occurred during discovery. You must not
free this glib::Error, it will be freed by
the discoverer.
Will be emitted in async mode when all pending URIs have been processed.
This signal is emitted after the source element has been created for, so the URI being discovered, so it can be configured by setting additional properties (e.g. set a proxy server for an http source, or set the device and read speed for an audio cd source).
This signal is usually emitted from the context of a GStreamer streaming thread.
source
source element
Will be emitted when the discover starts analyzing the pending URIs
The duration (in nanoseconds) after which the discovery of an individual URI will timeout.
If the discovery of a URI times out, the DiscovererResult::Timeout will be
set on the result flags.
The duration (in nanoseconds) after which the discovery of an individual URI will timeout.
If the discovery of a URI times out, the DiscovererResult::Timeout will be
set on the result flags.
DiscovererStreamInfo specific to audio streams.
Implements
DiscovererStreamInfoExt, glib::object::ObjectExt
Returns
the average or nominal bitrate of the stream in bits/second.
Returns
the number of channels in the stream.
Returns
the number of bits used per sample in each channel.
Returns
the language of the stream, or NULL if unknown.
Returns
the maximum bitrate of the stream in bits/second.
Returns
the sample rate of the stream in Hertz.
DiscovererStreamInfo specific to container streams.
Implements
DiscovererStreamInfoExt, glib::object::ObjectExt
Returns
the list of
DiscovererStreamInfo this container stream offers.
Free with DiscovererStreamInfo::list_free after usage.
Structure containing the information of a URI analyzed by Discoverer.
Implements
DiscovererInfoExt, glib::object::ObjectExt
Trait containing all DiscovererInfo methods.
Implementors
Parses a glib::Variant as produced by DiscovererInfoExt::to_variant
back to a DiscovererInfo.
variant
A glib::Variant to deserialize into a DiscovererInfo.
Returns
A newly-allocated DiscovererInfo.
Returns
A copy of the DiscovererInfo
Finds all the DiscovererAudioInfo contained in self
Returns
A glib::List of
matching DiscovererStreamInfo. The caller should free it with
DiscovererStreamInfo::list_free.
Finds all the DiscovererContainerInfo contained in self
Returns
A glib::List of
matching DiscovererStreamInfo. The caller should free it with
DiscovererStreamInfo::list_free.
Returns
the duration of the URI in gst::ClockTime (nanoseconds).
Deprecated
This functions is deprecated since version 1.4, use
DiscovererInfoExt::get_missing_elements_installer_details
Returns
Miscellaneous information stored as a gst::Structure
(for example: information about missing plugins). If you wish to use the
gst::Structure after the life-time of self, you will need to copy it.
Get the installer details for missing elements
Returns
An array of strings
containing informations about how to install the various missing elements
for self to be usable. If you wish to use the strings after the life-time
of self, you will need to copy them.
Returns
the result of the discovery as a DiscovererResult.
Returns
the whether the URI is seekable.
Returns
the structure (or topology) of the URI as a
DiscovererStreamInfo.
This structure can be traversed to see the original hierarchy. Unref with
gst_discoverer_stream_info_unref after usage.
Returns
the list of
all streams contained in the info. Free after usage
with DiscovererStreamInfo::list_free.
Finds the DiscovererStreamInfo contained in self that match the
given streamtype.
streamtype
a glib::Type derived from DiscovererStreamInfo
Returns
A glib::List of
matching DiscovererStreamInfo. The caller should free it with
DiscovererStreamInfo::list_free.
Finds all the DiscovererSubtitleInfo contained in self
Returns
A glib::List of
matching DiscovererStreamInfo. The caller should free it with
DiscovererStreamInfo::list_free.
Returns
all tags contained in the URI. If you wish to use
the tags after the life-time of self, you will need to copy them.
Returns
TOC contained in the URI. If you wish to use
the TOC after the life-time of self, you will need to copy it.
Returns
the URI to which this information corresponds to.
Copy it if you wish to use it after the life-time of self.
Finds all the DiscovererVideoInfo contained in self
Returns
A glib::List of
matching DiscovererStreamInfo. The caller should free it with
DiscovererStreamInfo::list_free.
Serializes self to a glib::Variant that can be parsed again
through DiscovererInfo::from_variant.
Note that any gst::Toc (s) that might have been discovered will not be serialized
for now.
flags
A combination of DiscovererSerializeFlags to specify
what needs to be serialized.
Returns
A newly-allocated glib::Variant representing self.
Result values for the discovery process.
The discovery was successful
the URI is invalid
an error happened and the GError is set
the discovery timed-out
the discoverer was already discovering a file
Some plugins are missing for full discovery
Base structure for information concerning a media stream. Depending on the
stream type, one can find more media-specific information in
DiscovererAudioInfo, DiscovererVideoInfo, and
DiscovererContainerInfo.
The DiscovererStreamInfo represents the topology of the stream. Siblings
can be iterated over with DiscovererStreamInfoExt::get_next and
DiscovererStreamInfoExt::get_previous. Children (sub-streams) of a
stream can be accessed using the DiscovererContainerInfo API.
As a simple example, if you run Discoverer on an AVI file with one audio
and one video stream, you will get a DiscovererContainerInfo
corresponding to the AVI container, which in turn will have a
DiscovererAudioInfo sub-stream and a DiscovererVideoInfo sub-stream
for the audio and video streams respectively.
Implements
DiscovererStreamInfoExt, glib::object::ObjectExt
Trait containing all DiscovererStreamInfo methods.
Implementors
DiscovererAudioInfo, DiscovererContainerInfo, DiscovererStreamInfo, DiscovererSubtitleInfo, DiscovererVideoInfo
Decrements the reference count of all contained DiscovererStreamInfo
and fress the glib::List.
infos
a glib::List of DiscovererStreamInfo
Returns
the gst::Caps of the stream. Unref with
gst_caps_unref after usage.
Deprecated
This functions is deprecated since version 1.4, use
DiscovererInfoExt::get_missing_elements_installer_details
Returns
additional information regarding the stream (for
example codec version, profile, etc..). If you wish to use the gst::Structure
after the life-time of self you will need to copy it.
Returns
the next DiscovererStreamInfo in a chain. None
for final streams.
Unref with gst_discoverer_stream_info_unref after usage.
Returns
the previous DiscovererStreamInfo in a chain.
None for starting points. Unref with gst_discoverer_stream_info_unref
after usage.
Returns
the stream ID of this stream. If you wish to
use the stream ID after the life-time of self you will need to copy it.
Returns
a human readable name for the stream type of the given self (ex : "audio",
"container",...).
Returns
the tags contained in this stream. If you wish to
use the tags after the life-time of self you will need to copy them.
Returns
the TOC contained in this stream. If you wish to
use the TOC after the life-time of self you will need to copy it.
DiscovererStreamInfo specific to subtitle streams (this includes text and
image based ones).
Implements
DiscovererStreamInfoExt, glib::object::ObjectExt
Returns
the language of the stream, or NULL if unknown.
DiscovererStreamInfo specific to video streams (this includes images).
Implements
DiscovererStreamInfoExt, glib::object::ObjectExt
Returns
the average or nominal bitrate of the video stream in bits/second.
Returns
the depth in bits of the video stream.
Returns
the framerate of the video stream (denominator).
Returns
the framerate of the video stream (numerator).
Returns
the height of the video stream in pixels.
Returns
the maximum bitrate of the video stream in bits/second.
Returns
the Pixel Aspect Ratio (PAR) of the video stream (denominator).
Returns
the Pixel Aspect Ratio (PAR) of the video stream (numerator).
Returns
the width of the video stream in pixels.
Returns
true if the video stream corresponds to an image (i.e. only contains
one frame).
Returns
true if the stream is interlaced, else false.