GstElement Information about audio buffers. Information about audio buffers. audioraw Reads data from a file. You can seek to a specific location by setting the offset. GstAsyncDiskSrc GstAudioSink GstAudioSrc GstColorSpace A connection is a bas class for a generic connection between elements. A connection is typically a bas class for queues. Generic connection between elements. GstConnection GstEsdSink Filters take data in and spit data out. They are the main Element in a filter graph. Filters have zero or more inputs and zero or more outputs. Filters are connected together to form filter graphs. A GstFilter is the base class and is not very usefull on its own. Take data in and spit data out GstFilter GstGetbits The point of the metadata is to provide some context for each buffer. In the case of audio data, for instance, it would provide the samplerate, bit depth, and channel count. The trick is that there may be multiple types of metadata ganged onto a single buffer. This is why they're going to be a GList. This does mean extra overhead in all cases, but I think it's minimal. The GList type uses a chunk allocater so we're not wasting too much memory or time when adding to the list. The trick is dealing with these structs as they pass through a pipeline, since they have potentially different mutability properties. For instance, if you've got a mp3 decoder connected to a tee, which sends the buffers off to both the decoder and a spectrum analyzer (and then a visualization element). The preferred setup would be where every time a audio/raw metadata comes down the pipe (indicating a potential change in audio format), the audiosink and spectrum would just save off pointers. So when exactly does this metadata go away (deallocated)? Well, that means metadata has to be refcounted. But that gets rather hairy. OK, in the simple case you create a metadata struct, it comes with refcount set to 1. You pass it through, it stays one, eventually someone drops the last reference on the buffer it's tied to, you free the metadata too. Easy. What if you tee? You could go through and for every metadata in the buffer, increment the refcount by the same as the buffer. So in the above case (tee'd), the audiosink and spectrum would get the buffer with a refcount of 2, and it'd have a metadata with refcount 2. Do they ref it each themselves, then unref the buffer? Or do they remove the metadata? Removing the metadata would require a buffer CoW, which would suck, so yes, they'd just ref the metadata. But.... what if they're all in different threads? Then we're off into the magical world of mutexes. Everything with a refcount in a threaded world must be mutexed, else you can do atomic increment and atomic dec and test. Can this be done from C easily? Perhaps it needs to be found from kernel includes via autoconf? The goal in designing the way metadata will be defined and used is to keep it as simple as possible. The basis for accomplishing this is the fact that in order to actually use (rather than just pass) the metadata, you have to know what the fields are, which means you have to have compiled in support for that metadata at build time. Therefore, if you're using metadata, you must have build-time access to the necessary include file that defines it. So, given that you've got an include file, it would be nice if the whole thing could be contained there. This would limit the need to be linked against something, or have load-time requirements as to that has to be loaded before you are. Given that really all metadata is is a region of memory of a given size with a certain signature, this isn't all that hard. First you lay out the struct that defines the metadata. Then you set up #defines that expand to the size of the struct in question, as well as the four-cc code that defines the type. The work is done by a few #defines, a la the #defines used in all Gtk objects. The first is a NEW() method that allocates the memory for the metadata and fills in all the normal fields (type, size, utility functions). Because of the way it's defined (as a #define, no less), you'll have to invoke it as META_NEW(meta), since it can't return() anything. Another #define will check to make sure a meta is indeed that type by verifying the type code and size. Theoretically, meta types can overlap with the same fourcc code, as long as they have different sizes. But I probably ought to have a global public registry so people writing things don't conflict. MSFT got that right, at least. So, a hairy problem is what to do when there are utility functions associated with one of these things. One option is to not bother with them. This is very likely a possible solution, since metadata is supposed to be flat memory of a given size. Not much to do to either free or copy it, is there? Provide context for buffers GstMeta The sink is the end of the filter graph. A typical sink would be an audio or a video card. The end point of a filter graph GstSink A GstSrc is the start of a filter graph. It typically is a file or an audio source. It provides data for the next element in the graph. The start point of a filter graph GstSrc plugin Frequencies of a spectrum analysis. Frequencies of a spectrum analysis. spectrum Information about video buffers. Information about video buffers. videoraw The maximum number of cothreads we are going to support. The default stack size of a cothread. Use this macro to show debugging info. This is only usefull when developing new plugin elements. If you #define DEBUG_ENABLED before including gst/gst.h, this macro will produce g_print messages. @format: the format specification as in g_print @args...: arguments @format: @args...: @format: @args...: @format: @args...: @format: @args...: @element: @format: @args...: @element: @object: @format: @args...: @obj: @klass: @obj: @klass: @obj: @klass: @obj: @klass: @buf: @buf: Retrieves the type id of the data in the buffer. @buf: GstBuffer @obj: @klass: A flag indicating that MMX instructions are supported. A flag indicating that SSE instructions are supported. Combine #GST_DEBUG_ENTER and #GST_DEBUG_SET_STRING. @cat: @format: @args...: @cat: @format: @args...: Set the debug string for the current function, typically containing the arguments to the current function, i.e. "('element')" @format: printf-style format string @args...: printf arguments @obj: @klass: @obj: @klass: Query whether this object has multiple input pads. @obj: Element to query for multiple input pads. @obj: @klass: <<<<<<< gstreamer-unused.sgml @obj: @klass: @obj: @klass: @obj: @klass: @obj: @klass: @obj: @klass: subclass use this to start their flag enumeration >>>>>>> 1.23.2.3 @obj: @klass: @obj: @klass: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @obj: @meta: Retrieve the flags of the given meta information. @meta: the meta information Check if a given flag is set. @meta: the meta data to test @flag: the flag to test Set a flag in the meta data. @meta: the meta data @flag: the flag to set Clear a flag in the meta data. @meta: the meta data @flag: the flag to clear @obj: @klass: subclasses can use this value to start the enumeration of their flags @obj: @klass: Indicate that this pad will always be available. Use this in the factory definition. Starts the declaration of a the capabilities for this padtemplate. @a...: a capability factory Indicates that this pad will be available on request. Use this in the factory definition. Indicates a sinkpad for the padfactory. Indicate that this pad will become available depending on the media type. Use this in the factory definition. Indicates a srcpad for the padfactory. @obj: @klass: @a: @b: @a: Create a fourcc property out of an integer value. @a: the integer value @obj: @klass: Get the EOS function of the real pad. @pad: the real pad to query. Get the pullfunction of the real pad. @pad: the real pad to query. Get the pushfunction of the real pad. @pad: the real pad to query. Get the QoS function of the real pad. @pad: the real pad to query. @obj: @klass: @obj: @klass: @obj: This macro checks to see if the GST_SRC_ASYNC flag is set. @obj: GstSrc to check for flag in. @klass: This macro returns the entire set of flags for the object. @obj: GstSrc to return flags for. Query a GstSrc for the ASYNC flag @obj: The GstSrc to query This macro sets the given flags. @src: @flag: Flag to set, can by any number of bits in guint32. @obj: GstSrc to set flag in. This macro usets the given flags. @src: @flag: Flag to set, must be a single bit in guint32. @obj: GstSrc to unset flag in. This macro checks to see if the given state is set. @obj: Element to check for state. @flag: State to check for, must be a single bit in guint32. The Element is going from the PLAYING state to the READY state. The Element is going from the READY state to the PLAYING state. This macro sets the given state on the element. @obj: Element to set state of. @flag: State to set, can be any number of bits in guint32. This macro unsets the given state on the element. @obj: Element to unset state of. @flag: State to unset, can be any number of bits in guint32. @obj: @klass: @obj: @klass: >>>>>>> 1.23.2.3 Specify how many bytes to read at a time. Get the size of the current file. Specify the location of the file to read. Specify the current offset in the file. GST_ASYNCDISKSRC_OPEN the asyncdisksrc is open for reading @GST_ASYNCDISKSRC_OPEN: @GST_ASYNCDISKSRC_FLAG_LAST: The buffer is sent to the sound card. @gstaudiosink: the object which received the signal. @arg1: the audiosink. The number of bytes per read. The number of channels (mono, stereo, ...) Get the current number of bytes read. The audio format as defined in soundcard.h The frequency. The function called when a buffer has to be created for this pool. @pool: the pool from which to create the buffer @user_data: any user data @Returns: a new buffer from the pool This function will be called when the given buffer has to be returned to the pool. @pool: the pool to return the buffer to @buffer: the buffer to return @user_data: any user data @GST_CAPS_ALWAYS: @GST_CAPS_MAYBE: Is emited after the buffer has been written to the disk. @gstdisksink: the object which received the signal. The filename to write to. Get the size of the file. @lock: for locking purposes @flags: the flags of the meta data @data: the meta data @size: the size of the meta data Flags indicating properties about the meta data. @GST_META_FREEABLE: the meta data can be freed Indicates this pad is active <<<<<<< gstreamer-unused.sgml The function that will be called in an EOS case. @pad: the pad that needs to be set to EOS state @Returns: TRUE if EOS was successful, FALSE otherwise Defines an entry for a padfactory. The padfactory. The function that will be called when pulling buffers. @pad: the pad to pull @Returns: a GstBuffer The function that will be called when pushing a buffers. @pad: the pad to push @buf: a GstBuffer to push The function that will be called when a QoS message is sent. @pad: the pad that sent the QoS message @qos_message: the message @GST_PROPS_END_ID_NUM: @GST_PROPS_LIST_ID_NUM: @GST_PROPS_INT_ID_NUM: @GST_PROPS_INT_RANGE_ID_NUM: @GST_PROPS_FOURCC_ID_NUM: @GST_PROPS_BOOL_ID_NUM: Specify wether the queue blocks or not. The number of channels. The fequency. An eos signal is triggered whenever the GstSrc has reached the end of the stream. @gstsrc: the object which received the signal. @arg1: the object which received the signal Flags for the GstSrc element @GST_SRC_ASYNC: Indicates that this src is asynchronous @GST_SRC_FLAG_LAST: subclasses can use this to number their flags Query the element for the current mime type Is trigered whenever the state of an element changes @gstelement: the object which received the signal. @arg1: the new state of the object @cat: @format: @args...: @cat: @element: @format: @args...: @meta: @format: @channels: @frequency: @bps: @meta: @bands: @channels: @interleaved: @lowfreq: @highfreq: @steps: @base: @swidth: @sheight: @bytes_per_line: @wx: @wy: @overlay_element: @clip_count: @overlay_clip: @width: @height: @did_overlay: @fully_obscured: @meta: @format: @visual: @width: @height: @overlay_info: @dga_info: @x1: @x2: @y1: @y2: @Returns: @pad: @buf: @Returns: @name: @Returns: @audiosink: @channels: @audiosink: @format: @audiosink: @frequency: @audiosink: @Returns: @name: @Returns: @src: @autoplug: @srcpad: @sinkpad: @Varargs: @Returns: @srccaps: @sinkcaps: @parent: @Returns: @factory: @parent: @Returns: @bin: @element: @bin: @Returns: @bin: @element: @bin: @bin: @element: @manager: @buffer: @meta: @buffer: @Returns: @buffer: @Returns: @pool: @buffer: @pool: @Returns: @pool: @create: @user_data: @pool: @destroy: @user_data: @buffer: @meta: @fromcaps: @tocaps: @Returns: @name: @mime: @props: @Returns: @factory: @Returns: @factory: @counter: @Returns: @count: @Returns: @name: @Returns: @connection: @Returns: @element: @state: @Returns: @Returns: @self: @parent: @Returns: @elements: @argc: @argv: @Returns: @Returns: @element: @templ: @Returns: @temp: @element: @parent: @Returns: @elementfactory: @id: @elementfactory: @id: @factory: @caps: @Returns: @factory: @caps: @Returns: @elementfactory: @parent: @Returns: @elementfactory: @factory: @parent: @Returns: @pad: @buf: @Returns: @name: @Returns: @esdsink: @channels: @esdsink: @format: @esdsink: @frequency: @esdsink: @pad: @buf: @Returns: @name: @Returns: @Returns: @name: @Returns: @src: @pad: @buf: @Returns: @name: @Returns: @name: @fd: @Returns: @Returns: @Returns: @name: @Returns: @Returns: @pad: @buf: @Returns: @name: @Returns: Create new meta data. @type: the type of the meta data to create @size: @Returns: @meta: @meta: @Returns: @Returns: @pad: @parent: Call the EOS function of the pad @pad: the pad to call the eos function of. @pad: @Returns: @pad: @name: @Returns: @pad: @Returns: @pad: @Returns: @pad: @Returns: @Returns: @pad: @Returns: @pad: @qos_message: @pad: @offset: @size: @Returns: @pad: @parent: @pad: @parent: @Returns: @nextpad: @Varargs: @Returns: @pad: @caps: @pad: @Returns: @pad: @eos: @pad: @pull: @pad: @qos: @pad: @id: @name_template: @direction: @presence: @caps: @Returns: @Returns: @plugin: @factory: @plugin: @factory: @plugin: @factory: @plugin: @Returns: @plugin: @Returns: @plugin: @Returns: @name: @Returns: @name: @Returns: @mime: @factory: @Returns: @factory: @counter: @Returns: @pad: @buf: @Returns: @name: @Returns: @connection: @Returns: @name: @Returns: @src: @Returns: @name: @Returns: @Returns: @src: @src: @offset: @size: @src: @pad: @buf: @Returns: @name: @Returns: @tee: @Returns: @Returns: @thread: @arg: @id: @sink: @id: @src: @sinkid: @srcid: @Returns: @id: @Returns: @id: @Returns: @parent: @Returns: @type: @parent: @Returns: @parent: @Returns: @factory: @parent: @Returns: @object: @argname: @Returns: @buffer: @size: @root: @Returns: @name: @Returns: @name: @Returns: