mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
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remove completely outdated random docs
Original commit message from CVS: remove completely outdated random docs
This commit is contained in:
Thomas Vander Stichele
parent
3278ca54a7
commit
5a303611c2
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@ -1,36 +0,0 @@
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compile fixes:
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- BSD compatibility fixes (MAP_ANON)
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- libxml compile problems fix
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- compile fixes for non x86 architectures
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(mpg123, mpeg_play, getbits, videoscale, ac3dec)
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- mpeg2enc asm comment fixes
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bug fixes:
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- videoscaler/colorconversion fixes
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- OSS audiosink bug fix
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- reworked the queue threading code
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- fixed the /etc/gstreamer permissions problem
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- various minor bug fixes
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changes:
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- state change modifications
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- _request pad implemented for muxer/mixer/aggregator
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elements. also _request_compatible additions.
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- massive ghostpad changes
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- EOS handling (not for gstmediaplay)
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- icecast send plugin using libshout
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- lots of GstObject changes (XML save, name, parent
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properties fixes)
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- preliminary XML namespaces.
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- added support for custom app tags in the XML save/load
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routines (preliminary support)
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- cothreads updates for ALPHA/ARM
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- asyncdisksrc is gone in favor of a better disksrc
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- getregion rework
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- videoscaler/colorconversion updates
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- manual/docs updates
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@ -1,78 +0,0 @@
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Version 0.2.0
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-------------
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compile fixes:
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- added a gstreamer.m4 script.
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- more compatibility fixes for various xml libs.
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- more BSD patches.
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- gstversion.h added.
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- numerous configure changes
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- compatibility with autoconf 2.50
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bug fixes:
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- allow quoted and escaped args in gstparse.c
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- preliminary work on proper refcounting
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- numerous bugfixes in the plugins.
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changes:
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- better CPU detection
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- dynamic autopluggers with a new more powerful API.
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- sparc cothreads.
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- reworked arg setting (gstparse.c and gstelement.c xml handling)
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- testsuite directory added
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- incremental scheduling is now implemented.
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- dynamic adding and removing of elements in a runnning
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pipeline.
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- proper synchronisation and thread interlock.
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- caps negotiation
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- allow elements to exchange and agree on a media type.
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- get rid of the metadata.
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- man pages added for command line utils.
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- more documentation updates
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- colourful debug system
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- new plugin initialisation mechanism so that the core can refuse
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to load plugins build with an incompatible version number.
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- added bash comand line completion for gstreamer-launch
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- pipefilter is now decoupled as it should be
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- added gnomevfssrc as the prefered element in gstplay
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- PAUSED and PLAYING state are now swapped.
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- elements cannot have identical names when added to a bin.
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- lots of plugin updates.
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- reworked AVI decoder.
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plugins:
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- xmms input, effect
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- mpeg2dec based on libmpeg2
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- alsa sink and src.
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- rtp sink
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- FLX decoder
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- multidisksrc
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- a new X-only videosink
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- stero2mono and mono2stereo
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- mulaw encoder/decoder
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- colorspace converter
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- artsdsink
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- alaw encoder/decoder
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- mad mp3 decoder
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- passthrough and script to create a plugin boilerplate
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- volenv (a volume envelope filter)
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- adder (an audio mixer)
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- arts plugin
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- 1394src (a firewire source)
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- DV decoder.
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- aasink
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- intfloat and floatint converter
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- autoplugcache
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- gstoss to import audio from legacy apps by hijacking /dev/dsp
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- lav encoder (for interoperability with mjpegtools)
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- gnomevfssrc (read data from gnomevfs) and gnomevfssink
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- sdlvideosink (display video using SDL)
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- quicktime decoder based on openquicktime.
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- audiofile src and sink.
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- level (level detection plugin)
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- gsm decoder/encoder (based on libgsm)
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@ -1,57 +0,0 @@
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- Restructure CVS
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- Move gstreamer/ to gstreamer-0.1.0/
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- Re-import entire project into gstreamer/
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- Convert to GObject
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- Get editor working better
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- object hierarchy rewrite?
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- make autoplugging algorithms pluggable
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- create a dynamic autoplugger
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- make scheduling algorithms pluggable
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- try some really hard cases
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- add help functions to traverse the hierarchy
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- gst_bin_traverse_with_func(GstBin *bin, funcptr)
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- bufferpool passing
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- general
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- thread-safety
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- EOS handling
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- QoS handling
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- clock sync
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- test suite
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- test cases
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- regression tests
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- XML stuff
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- save signals
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- xml namespaces
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- caps/props
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- APIs
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- caps negociation
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- props weighting
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- metadata
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- docs
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- manuals
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- plugin-writers-guide
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- design guide
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- performance guide
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- bindings
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- perl
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- guile
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- BONOBO
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- corba
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- ...
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- after that we'll do more plugins :-)
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@ -1,81 +0,0 @@
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OUTDATED
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--------
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GstElementFactory:
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Base class for all elementfactories. Is a single-instance (per program)
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object that creates objects of the associated GstElement derivative.
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GstPlugin:
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Defines a given plugin. Records plugin name, function pointers, details,
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etc. Includes a list of GstElementFactories that are associated with
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this plugin.
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GstBuffer
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GstPad
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GstObject
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GstSrc
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GstDiskSrc
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GstHTTPSrc
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*
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GstAsyncSrc
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GstAsyncDiskSrc
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*
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GstFilter
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GstVideoFilter
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GstVideoMPEG
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*
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GstAudioFilter
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GstAudioMPEG
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*
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*
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GstSink
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GstAudioSink
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GstAudioOSSSink
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GstAudioALSASink
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GstAudioESDSink
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*
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GstVideoSink
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GstVideoGDKRGBSink
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GstVideoXvSink
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*
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*
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*
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GstBin
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GstPipeline
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GstThread
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GstConnection
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GstQueue
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GstNetwork
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GstSHM
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GstObject:
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Base class for all streamer objects (duh), defines some basic stuff like a
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pointer to the master pipeline for the object.
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GstBin:
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Contains a bunch of GstObjects.
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GstPipeline:
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A bin that can be used raw in an application. The object that gets
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embedded into applications. Can contain any set of GstObjects. Nothing
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but a convenience object for the moment, will eventually be *the* object
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dealt with externally.
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GstThread:
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A bin that will become a thread if possible when the pipeline is started
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up. Can contain any set of GstObjects except another GstThread. All
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starting points and/or clocked events must be registered with this object,
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to be dealt with in the separate thread.
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In a cothread-based container, all elements are run as cothreads.
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Chain-function based elements are wrapped by a generic element-class
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function that just calls the chain function repeatedly after pulling a
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buffer for it. (in reality, chain functions are only usable in the
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single-input case)
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The fundamental component of GStreamer is the "element", an object that
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sources and/or sinks data. Elements are connected to each other via
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"pads", which are extremely light-weight generic connections. Elements
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can be contained inside "bins", which themselves are elements.
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A pipeline consists of any number of elements, connected to each other one
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after another. A source would connect to one end of a decoder, which in
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turn would be connected (on the other end) to a sink, such as a sound
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card. Other elements can be located anywhere in the pipeline, including
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tees and transcoders.
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@ -1,7 +0,0 @@
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short name
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class
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long name
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descripion
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author
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version
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copyright
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@ -1,4 +0,0 @@
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NOTE TO SELF:
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there are a lot of routines here that should be returning gboolean's for
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status, rather than just plain failing.
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@ -1,14 +0,0 @@
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--src---------------------------- --sink----------------------------
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| |
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--srcpad--------| |--sinkpad-------
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| pad_push() . . |
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push() | ->chain . . ->chain | -> chain()
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| . . |
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----------------| |----------------
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| |
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chain() is the function provided by sink element
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sinkpad->chain is a pointer to that function
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srcpad->chain should be a copy of that pointer
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pad_push() calls the function pointer srcpad->chain
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push() is the function provided by the src element
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Here's a possible (huge, large, complete?) sequence of execution for an
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invocation of [GIST] playing a media stream. I'll start with a mp3 audio
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stream, but eventually this should be a mpeg a/v stream off the net with
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rolling capture (think ReplayTV/Tivo), pausing, rewinding, etc. This
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could easily be hundreds of lines by the time I'm done...
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This may look a lot like C in places, simply because that's the most
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efficient way of representing a given action.
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gst_init();
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pipeline = gst_pipeline_new();
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state =
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src = gst_disksrc_new("src","song.mp3");
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@ -1,45 +0,0 @@
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So, the method of having a _start() and _stop() function for each element
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just doesn't scale. In the case of pipeline/thread model with a PLAYING
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state bit, I have no way of passing a state change all the way down the
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graph, i.e. a thread sitting inside a supplied bin.
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Proposal is to have a single state-change class function, which gets
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passed a single argument (no more 'state' going along with RUNNING). This
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function can be overridden by each element as necessary, but must chain to
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the parent_class version of it. It does its work, just like [st]et_arg,
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in a case. It checks for STATE and ~STATE, and does the appropriate
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steps. All the _start() and _stop() functions get moved into this one, in
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the GST_STATE_RUNNING and ~GST_STATE_RUNNING cases.
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This allows bins to and derivations thereof to simply pass through any
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state they don't understand. Meta-elements will also pass through.
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There may need to be some mechanism that provides for setting state on
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only a certain type. This can be provided as an alternate path supplied
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by bins. The bin is the one that would do the work in any case. Simply
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provide class function for bins that does the selective stuff, and a main
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_bin_ function that calls this class function. The supplied class
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function for each bin would simply check against the given GtkType before
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setting its state. Derivations of GstBin would always get it.
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Success chaining (gbooleans) starts to get a little hairier...
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Functions:
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gst_element_set_state(element,state) is called by the application to set
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the state for an element (or bin).
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elementclass->change_state() is the class function that actually does the
|
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setting of the state for this element. Any subclass implementation will
|
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chain to the parent_class's version.
|
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||||
gst_element_change_state(element,state) is the Element class's
|
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implementation of the change_state() function. It simply sets the state.
|
||||
|
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gst_bin_set_state_type(element,state,type) is a specialized function for
|
||||
bins only that sets the type only on elements of that type.
|
||||
|
||||
binclass->change_state_type() is the class function that does the
|
||||
selective
|
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|
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@ -1,75 +0,0 @@
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OUTDATED
|
||||
--------
|
||||
|
||||
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GST State Bits and Transition Rules (graph to follow)
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||||
-----------------------------------
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|
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These are the 'new' state bits and what they mean.
|
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|
||||
What the state bits are:
|
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GST_STATE_COMPLETE: if the element has enough data, but is not in any kind
|
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of running or explicitely stopped state. ready to be used.
|
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GST_STATE_RUNNING: this is the normal state of the pipeline, where data
|
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goes all the way through the pipeline normally.
|
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GST_STATE_DISCOVERY: anything the element does in this state must be reset
|
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after discovery. any data read from sync source must be cached.
|
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GST_STATE_PREROLL: not a lot different from PLAYING, except sinks don't
|
||||
render what they're getting. useful for elements that require
|
||||
data to get in sync, such as an MPEG video decoder that needs
|
||||
IBBPBB before starting at the next P.
|
||||
|
||||
|
||||
|
||||
Basic transition rules:
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||||
|
||||
Completeness is based on the element having enough information to actually
|
||||
do something. GST_STATE_COMPLETE is required for any other state to be
|
||||
valid, though the only invariant is that you can't be RUNNING unless
|
||||
you're COMPLETE. In fact, AFAICT, that's the *only* invariant.
|
||||
|
||||
The element is entirely in control of this bit at all times. There is no
|
||||
way to externally change this bit except by changing the state of the
|
||||
element in such a way as to effect a change.
|
||||
|
||||
|= GST_STATE_COMPLETE
|
||||
setting whatever the last bit of info the element was looking for
|
||||
(gst_object_set)
|
||||
|
||||
&= ~GST_STATE_COMPLETE
|
||||
changing anything that invalidates the complete state of the element
|
||||
|
||||
|
||||
Whether the element is running or not, on the other hand, is almost
|
||||
entirely out of the hands of the individual element. This is generally
|
||||
turned on by way of gst_element_run() as called by the parent (ultimately
|
||||
by the Pipeline), which happens to optionally call a function private to
|
||||
the element to prepare it. As per docs/random/gboolean, very likely this
|
||||
function should return a TRUE/FALSE.
|
||||
|
||||
Generally, I think if there is no such function, the generic element code
|
||||
should go ahead and set the state, and trigger the state_changed signal,
|
||||
returning TRUE. If there is a function, call it. If it returns TRUE,
|
||||
fire off the signal (since the signal is actually an Element signal
|
||||
anyway, why eat another function call?). Return the result regardless.
|
||||
|
||||
|= GST_STATE_RUNNING
|
||||
starting up the pipeline with gst_pipeline_start
|
||||
|
||||
~= ~GST_STATE_RUNNING
|
||||
stopping the pipeline with gst_pipeline_stop, or some error state
|
||||
|
||||
gst_pipeline_start() simply calls the gst_element_start() function on each
|
||||
of the elements in it. This sets the RUNNING bit of each element, and for
|
||||
GstBin's it loops through that list. gst_pipeline_start() is just a
|
||||
special case version of gst_bin_start(). All start() functions are
|
||||
GstElementClass functions, meaning you can start any element the same way.
|
||||
|
||||
The pipeline can be stopped the same way, but more likely the pipeline
|
||||
will be stopped due to some stoppage condition, such as EOF on the source
|
||||
file, or the parser being told to stop the stream. In the EOF case, it
|
||||
would turn its RUNNING bit off, then call the stop() class function on its
|
||||
parent. This would trigger an up-hill, breath-first traversal of the
|
||||
whole graph. Alternately, if each element lists its uber-parent (the
|
||||
Pipeline) it can simply inform the pipeline directly, causing a
|
||||
depth-first traversal just like the start() case.
|
||||
|
|
@ -1,82 +0,0 @@
|
|||
OUTDATED
|
||||
--------
|
||||
|
||||
Since the plan generation only happens as a result of the state mechanism,
|
||||
I'll describe that first.
|
||||
|
||||
It's supposed to be recursive, such that setting the state on a Bin
|
||||
recursively sets all the children. However, this needs to be rethought
|
||||
somewhat, in light of some recent ideas on the actual definition of some
|
||||
of the states.
|
||||
|
||||
The mechanism is thus: When you call gst_element_set_state(element,state),
|
||||
it calls the change_state() class method. The basic Element-provided
|
||||
version just sets or unsets the state. A more complex element like the
|
||||
audiosink will switch on the state and do certain things like open or
|
||||
close the sound card on transition to/from various states. The success or
|
||||
failure of these actions can determine whether or not the state gets
|
||||
[un]set as requested.
|
||||
|
||||
GtkObject signals enter in here, as whenever a state is successfully
|
||||
changed, the STATE_CHANGE signal is fired, which gives higher-level code
|
||||
the ability to do something based on the change.
|
||||
|
||||
The Bin's change_state function walks through all its children and sets
|
||||
their state. This is where things get interesting, and where things are
|
||||
going to need to be changed.
|
||||
|
||||
The issue is what the states are and mean. Currently the states are as
|
||||
follows (from gstelement.h):
|
||||
|
||||
typedef enum {
|
||||
GST_STATE_COMPLETE = (1 << 0),
|
||||
GST_STATE_RUNNING = (1 << 1),
|
||||
GST_STATE_DISCOVERY = (1 << 2),
|
||||
GST_STATE_PREROLL = (1 << 3),
|
||||
|
||||
GST_STATE_PLAYING = (1 << 4),
|
||||
GST_STATE_PAUSED = (1 << 5),
|
||||
|
||||
GST_STATE_MAX = (1 << 15),
|
||||
} GstElementState;
|
||||
|
||||
COMPLETE means all the necesary information is available to run, i.e. the
|
||||
filename for the disksrc, etc. RUNNING means that it's actually doing
|
||||
something, but that's fuzzy. PLAYING means there really is data flowing
|
||||
through the graph, where PAUSED temporary stops the flow. PLAYING &&
|
||||
PAUSED is the same idea as !PLAYING, but there are probably going to be
|
||||
many cases where there really is a distinction.
|
||||
|
||||
DISCOVERY is intended for the autoconnect case, in those instances where
|
||||
the only way to determine the input or output type of some pad is for an
|
||||
element to actually process some data. The idea in that case is that the
|
||||
source element would be responsible for sending the data non-destructively
|
||||
(in the case of a network client, it would have to save it all up, unless
|
||||
it has seek capabilities over the network), and all downstream elements
|
||||
process it in such a way as to not hose their own state. Or rather, when
|
||||
they cease to do discovery, they completely wipe their state as if nothing
|
||||
ever happened.
|
||||
|
||||
PREROLL is a local state, used for things like sending the first half of
|
||||
an MPEG GOP through the decoder in order to start playback at a frame
|
||||
somewhere in the middle of said GOP. Not sure how that will work,
|
||||
exactly.
|
||||
|
||||
|
||||
The issue is that these states aren't layered, and it most certainly isn't
|
||||
the case that a container isn't able to be of a certain state unless all
|
||||
of its children are. I guess I should explain the idea of reconfigurable
|
||||
pipelines:
|
||||
|
||||
Build an MP3 player, give it the ability to use audio effects plugins.
|
||||
Since you don't want to have to start the stream over again (especially if
|
||||
it's a network stream) every time you change the effect. This means you
|
||||
need to be able to freeze the pipeline in place to change it, without
|
||||
taking too much time.
|
||||
|
||||
This matters when you consider that certain state changes should render
|
||||
various state bits invalid. In the FROZEN state these won't happen,
|
||||
because the assumption is that they're temporary.
|
||||
|
||||
If you haven't noticed by now, the state system isn't entirely
|
||||
self-consistent yet. It needs work, and it needs discussion.
|
||||
|
|
@ -1,83 +0,0 @@
|
|||
OUTDATED
|
||||
--------
|
||||
|
||||
GST States and Transition Rules (graph to follow)
|
||||
-------------------------------
|
||||
|
||||
This should be a map of possible state transitions and what triggers them.
|
||||
|
||||
What the states are:
|
||||
GST_STATE_NEW: a new element has this, if it has nothing set except name.
|
||||
GST_STATE_INCOMPLETE: any element that has some, but not enough
|
||||
information to function is in this state.
|
||||
GST_STATE_COMPLETE: if the element has enough data, but is not in any kind
|
||||
of running or explicitely stopped state. ready to be used.
|
||||
GST_STATE_DISCOVERY: anything the element does in this state must be reset
|
||||
after discovery. any data read from sync source must be cached.
|
||||
GST_STATE_PREROLL: not a lot different from PLAYING, except sinks don't
|
||||
render what they're getting. useful for elements that require
|
||||
data to get in sync, such as an MPEG video decoder that needs
|
||||
IBBPBB before starting at the next P.
|
||||
GST_STATE_RUNNING: this is the normal state of the pipeline, where data
|
||||
goes all the way through the pipeline normally.
|
||||
GST_STATE_STOPPED: an explicit stop state, different from COMPLETE in that
|
||||
the state doesn't get reset.
|
||||
|
||||
|
||||
NULL -> GST_STATE_NEW
|
||||
creating an element (gst_*_new*)
|
||||
|
||||
GST_STATE_NEW -> GST_STATE_INCOMPLETE
|
||||
setting anything in the element that isn't sufficient to bring it
|
||||
to a useful state (gst_object_set)
|
||||
|
||||
GST_STATE_INCOMPLETE -> GST_STATE_COMPLETE
|
||||
setting whatever the last bit of info the element was looking for
|
||||
(gst_object_set)
|
||||
|
||||
GST_STATE_COMPLETE -> GST_STATE_INCOMPLETE
|
||||
changing anything that invalidates the complete state of the element
|
||||
|
||||
GST_STATE_COMPLETE -> GST_STATE_DISCOVERY
|
||||
setting the state to DISCOVERY
|
||||
[ used for autoplug ]
|
||||
|
||||
GST_STATE_DISCOVERY -> GST_STATE_COMPLETE
|
||||
setting the state !DISCOVERY
|
||||
[ used when autoplug is over ]
|
||||
|
||||
GST_STATE_DISCOVERY -> GST_STATE_PREROLL
|
||||
setting the state to PREROLL
|
||||
[ you can go straight to preroll from discovery if you want ]
|
||||
|
||||
GST_STATE_DISCOVERY -> GST_STATE_RUNNING
|
||||
setting the state to RUNNING
|
||||
[ you can even go straight to running from preroll ]
|
||||
|
||||
GST_STATE_DISCOVERY -> GST_STATE_STOPPED
|
||||
setting the state to STOPPED
|
||||
[ normally you'd go from discovery to stopped when you load a src ]
|
||||
|
||||
GST_STATE_PREROLL -> GST_STATE_RUNNING
|
||||
setting the state to RUNNING
|
||||
[ preroll generally leads straight to running, as in above ]
|
||||
|
||||
GST_STATE_PREROLL -> GST_STATE_STOPPED
|
||||
setting the state to STOPPED
|
||||
[ it is possible to go to stopped, i.e load file@time ]
|
||||
|
||||
GST_STATE_RUNNING -> GST_STATE_PREROLL
|
||||
setting the state to PREROLL
|
||||
[ unsure if you'd need this state, you'd go to stopped first ]
|
||||
|
||||
GST_STATE_RUNNING -> GST_STATE_STOPPED
|
||||
setting the state to STOPPED
|
||||
[ pause. ]
|
||||
|
||||
GST_STATE_STOPPED -> GST_STATE_PREROLL
|
||||
setting the state to PREROLL
|
||||
[ if you seek to intermediate time while stopped, you'd preroll to
|
||||
prepare to start running again immediately ]
|
||||
|
||||
GST_STATE_STOPPED -> GST_STATE_RUNNING
|
||||
setting the state to RUNNING
|
||||
|
|
@ -1,42 +0,0 @@
|
|||
OUTDATED
|
||||
--------
|
||||
|
||||
You might start by creating a source element and put it into a pipeline.
|
||||
At this point both element's state would be GST_STATE_NEW, since they
|
||||
don't have enough state to actually run yet. At this point you can set
|
||||
the filename of the source, and possibly bytesperread and other things.
|
||||
|
||||
Then you'd want to discover the data type of the file you're sourcing.
|
||||
This will typically be handled by the pipeline itself by calling
|
||||
gst_pipeline_autoplug(), or gst_pipeline_find_pad_type(), or somesuch. The
|
||||
pipeline would first set its state to GST_STATE_DISCOVERY. A gstfindtype
|
||||
sink would be added to the pipeline and connected to the source. Its
|
||||
HAVE_TYPE signal would be connected to a private pipeline function.
|
||||
|
||||
The pipeline would then set the the src state to GST_STATE_DISCOVERY, and
|
||||
call the src's push() function until a the type is set by the function
|
||||
connected to the gstfindtype element's signal. At this point the pipeline
|
||||
would disconnect the gstfindtype element from the src, set the type of the
|
||||
pad to the type returned by the gstfindtype element. At disconnection of
|
||||
the find element, the src's state automatically reverts to NEW.
|
||||
|
||||
(The trick with the sources when they do DISCOVERY is that synchronous
|
||||
sources can't go back and read data again. So perhaps I should set up a
|
||||
wrapper function for the push() function that uses either a sync or
|
||||
async function as provided by the src instance to provide DISCOVERY and
|
||||
normal operations. It would use a [GstBufferCache] to read ahead into
|
||||
memory if necessary, creating baby buffers as necessary to answer the
|
||||
needs of each DISCOVERY sequence.)
|
||||
|
||||
If you called find_pad_type(), it would return right about now, with the
|
||||
ID of the type it found. At the same time, if you have connected a signal
|
||||
to the pad's SET_TYPE signal, it would fire right as the type is set by
|
||||
the find_pad_type() function. This would allow your application to do its
|
||||
own selection of filters to connect to the pad.
|
||||
|
||||
If you called autoplug(), the pipeline would make a selection of element
|
||||
to connect. The element would be created (state=NEW), added to the
|
||||
pipeline, and the appropriate sink pad connected to the src in question.
|
||||
(Note that multi-sink elements won't be supported unless there's a really
|
||||
good and obvious way to do so) The whole process would repeat until the
|
||||
recently added element no longer has a src pad.
|
||||
Loading…
Reference in a new issue