Sets our main struct and passes it to the parent class
Create a new custom-typed event. This can be used for anything not handled by other event-specific functions to pass an event to another element. Make sure to allocate an event type with the GST_EVENT_MAKE_TYPE macro, assigning a free number and filling in the correct direction and serialization flags. New custom events can also be created by subclassing the event type if needed.
Create a new latency event. The event is sent upstream from the sinks and notifies elements that they should add an additional latency to the timestamps before synchronising against the clock. The latency is mostly used in live sinks and is always expressed in the time format.
Allocate a new newsegment event with the given format/values tripplets This method calls gst_event_new_new_segment_full() passing a default value of 1.0 for applied_rate
Allocate a new newsegment event with the given format/values triplets. The newsegment event marks the range of buffers to be processed. All data not within the segment range is not to be processed. This can be used intelligently by plugins to apply more efficient methods of skipping unneeded data. The position value of the segment is used in conjunction with the start value to convert the buffer timestamps into the stream time. This is usually done in sinks to report the current stream_time. position represents the stream_time of a buffer carrying a timestamp of start. position cannot be -1. start cannot be -1, stop can be -1. If there is a valid stop given, it must be greater or equal the start, including when the indicated playback rate is < 0. The applied_rate value provides information about any rate adjustment that has already been made to the timestamps and content on the buffers of the stream. (rate * applied_rate) should always equal the rate that has been requested for playback. For example, if an element has an input segment with intended playback rate of 2.0 and applied_rate of 1.0, it can adjust incoming timestamps and buffer content by half and output a newsegment event with rate of 1.0 and applied_rate of 2.0
Allocate a new qos event with the given values. The QOS event is generated in an element that wants an upstream element to either reduce or increase its rate because of high/low CPU load or other resource usage such as network performance. Typically sinks generate these events for each buffer they receive. proportion indicates the real-time performance of the streaming in the element that generated the QoS event (usually the sink). The value is generally computed based on more long term statistics about the streams timestamps compared to the clock. A value < 1.0 indicates that the upstream element is producing data faster than real-time. A value > 1.0 indicates that the upstream element is not producing data fast enough. 1.0 is the ideal proportion value. The proportion value can safely be used to lower or increase the quality of the element. diff is the difference against the clock in running time of the last buffer that caused the element to generate the QOS event. A negative value means that the buffer with timestamp arrived in time. A positive value indicates how late the buffer with timestamp was. timestamp is the timestamp of the last buffer that cause the element to generate the QOS event. It is expressed in running time and thus an ever increasing value. The upstream element can use the diff and timestamp values to decide whether to process more buffers. For possitive diff, all buffers with timestamp <= timestamp + diff will certainly arrive late in the sink as well. The application can use general event probes to intercept the QoS event and implement custom application specific QoS handling.
Allocate a new seek event with the given parameters. The seek event configures playback of the pipeline between start to stop at the speed given in rate, also called a playback segment. The start and stop values are expressed in format. A rate of 1.0 means normal playback rate, 2.0 means double speed. Negatives values means backwards playback. A value of 0.0 for the rate is not allowed and should be accomplished instead by PAUSING the pipeline. A pipeline has a default playback segment configured with a start position of 0, a stop position of -1 and a rate of 1.0. The currently configured playback segment can be queried with GST_QUERY_SEGMENT. start_type and stop_type specify how to adjust the currently configured start and stop fields in segment. Adjustments can be made relative or absolute to the last configured values. A type of GST_SEEK_TYPE_NONE means that the position should not be updated. When the rate is positive and start has been updated, playback will start from the newly configured start position. For negative rates, playback will start from the newly configured stop position (if any). If the stop position if updated, it must be different from -1 for negative rates. It is not possible to seek relative to the current playback position, to do this, PAUSE the pipeline, query the current playback position with GST_QUERY_POSITION and update the playback segment current position with a GST_SEEK_TYPE_SET to the desired position.
Generates a metadata tag event from the given taglist.
Increase the refcount of this event.
the main Gtk struct as a void*
Access the structure of the event.
Get the format, minsize, maxsize and async-flag in the buffersize event.
Get the latency in the latency event.
Get the update flag, rate, format, start, stop and position in the newsegment event. In general, gst_event_parse_new_segment_full() should be used instead of this, to also retrieve the applied_rate value of the segment. See gst_event_new_new_segment_full() for a full description of the newsegment event.
Get the update, rate, applied_rate, format, start, stop and position in the newsegment event. See gst_event_new_new_segment_full() for a full description of the newsegment event.
Get the proportion, diff and timestamp in the qos event. See gst_event_new_qos() for more information about the different QoS values.
Parses a seek event and stores the results in the given result locations.
Parses a tag event and stores the results in the given taglist location.
Create a new buffersize event. The event is sent downstream and notifies elements that they should provide a buffer of the specified dimensions. When the async flag is set, a thread boundary is prefered.
Gets the GstEventTypeFlags associated with type.
Get a printable name for the given event type. Do not modify or free.
Get the unique quark for the given event type.
the main Gtk struct
Description The event class provides factory methods to construct and functions query (parse) events. Events are usually created with gst_event_new_*() which takes event-type specific parameters as arguments. To send an event application will usually use gst_element_send_event() and elements will use gst_pad_send_event() or gst_pad_push_event(). The event should be unreffed with gst_event_unref() if it has not been sent. Events that have been received can be parsed with their respective gst_event_parse_*() functions. Events are passed between elements in parallel to the data stream. Some events are serialized with buffers, others are not. Some events only travel downstream, others only upstream. Some events can travel both upstream and downstream. The events are used to signal special conditions in the datastream such as EOS (end of stream) or the start of a new stream-segment. Events are also used to flush the pipeline of any pending data. Most of the event API is used inside plugins. Applications usually only construct and use seek events. To do that gst_event_new_seek() is used to create a seek event. It takes the needed parameters to specity seeking time and mode. Last reviewed on 2006-09-6 (0.10.10)