Struct gst::Pipeline

pub struct Pipeline {
    // some fields omitted
}

A GstPipeline is a special GstBin used as the toplevel container for the filter graph. The GstPipeline will manage the selection and distribution of a global GstClock as well as provide a GstBus to the application.

gst_pipeline_new() is used to create a pipeline. when you are done with the pipeline, use gst_object_unref() to free its resources including all added GstElement objects (if not otherwise referenced).

Elements are added and removed from the pipeline using the GstBin methods like gst_bin_add() and gst_bin_remove() (see GstBin).

Before changing the state of the GstPipeline (see GstElement) a GstBus can be retrieved with gst_pipeline_get_bus(). This bus can then be used to receive GstMessage from the elements in the pipeline.

By default, a GstPipeline will automatically flush the pending GstBus messages when going to the NULL state to ensure that no circular references exist when no messages are read from the GstBus. This behaviour can be changed with gst_pipeline_set_auto_flush_bus().

When the GstPipeline performs the PAUSED to PLAYING state change it will select a clock for the elements. The clock selection algorithm will by default select a clock provided by an element that is most upstream (closest to the source). For live pipelines (ones that return GST_STATE_CHANGE_NO_PREROLL from the gst_element_set_state() call) this will select the clock provided by the live source. For normal pipelines this will select a clock provided by the sinks (most likely the audio sink). If no element provides a clock, a default GstSystemClock is used.

The clock selection can be controlled with the gst_pipeline_use_clock() method, which will enforce a given clock on the pipeline. With gst_pipeline_auto_clock() the default clock selection algorithm can be restored.

A GstPipeline maintains a running time for the elements. The running time is defined as the difference between the current clock time and the base time. When the pipeline goes to READY or a flushing seek is performed on it, the running time is reset to 0. When the pipeline is set from PLAYING to PAUSED, the current clock time is sampled and used to configure the base time for the elements when the pipeline is set to PLAYING again. The effect is that the running time (as the difference between the clock time and the base time) will count how much time was spent in the PLAYING state. This default behaviour can be changed with the gst_element_set_start_time() method.

Methods

impl Pipeline

fn new(name: &str) -> Option<Pipeline>

Create a new pipeline with the given name.

fn new_from_str(string: &str) -> Result<Pipeline>

Creates a new pipeline using gst_parse_launch

unsafe fn new_from_gst_pipeline(pipeline: *mut GstPipeline) -> Option<Pipeline>

fn bus(&self) -> Option<Bus>

Gets the GstBus of pipeline . The bus allows applications to receive Message packets.

Trait Implementations

impl Sync for Pipeline

impl Send for Pipeline

impl PipelineT for Pipeline

fn as_pipeline(&self) -> &Pipeline

fn as_pipeline_mut(&mut self) -> &mut Pipeline

fn delay(&self) -> GstClockTime

Get the configured delay (see set_delay()).

fn set_delay(&mut self, delay: GstClockTime)

Set the expected delay needed for all elements to perform the PAUSED to PLAYING state change. delay will be added to the base time of the elements so that they wait an additional delay amount of time before starting to process buffers and cannot be GST_CLOCK_TIME_NONE.

unsafe fn gst_pipeline(&self) -> *const GstPipeline

Returns a const raw pointer to the internal GstElement

unsafe fn gst_pipeline_mut(&mut self) -> *mut GstPipeline

Returns a mut raw pointer to the internal GstElement

fn to_pipeline(&self) -> Pipeline

impl Transfer for Pipeline

unsafe fn transfer(self) -> *mut GstElement

Consumes the current object and transfers ownership of the raw pointer Used to transfer ownership to ffi functions, should be used when an ffi function expects full transfer of an object to avoid the original object to be unreferenced in the process