FlowCombiner

Utility struct to help handling #GstFlowReturn combination. Useful for #GstElements that have multiple source pads and need to combine the different #GstFlowReturn for those pads.

#GstFlowCombiner works by using the last #GstFlowReturn for all #GstPad it has in its list and computes the combined return value and provides it to the caller.

To add a new pad to the #GstFlowCombiner use gst_flow_combiner_add_pad(). The new #GstPad is stored with a default value of %GST_FLOW_OK.

In case you want a #GstPad to be removed, use gst_flow_combiner_remove_pad().

Please be aware that this struct isn't thread safe as its designed to be used by demuxers, those usually will have a single thread operating it.

These functions will take refs on the passed #GstPads.

Aside from reducing the user's code size, the main advantage of using this helper struct is to follow the standard rules for #GstFlowReturn combination. These rules are:

* %GST_FLOW_EOS: only if all returns are EOS too * %GST_FLOW_NOT_LINKED: only if all returns are NOT_LINKED too * %GST_FLOW_ERROR or below: if at least one returns an error return * %GST_FLOW_NOT_NEGOTIATED: if at least one returns a not-negotiated return * %GST_FLOW_FLUSHING: if at least one returns flushing * %GST_FLOW_OK: otherwise

%GST_FLOW_ERROR or below, GST_FLOW_NOT_NEGOTIATED and GST_FLOW_FLUSHING are returned immediately from the gst_flow_combiner_update_flow() function.

class FlowCombiner {

protected

GstFlowCombiner* gstFlowCombiner;

protected

bool ownedRef;

GstFlowCombiner* getFlowCombinerStruct(bool transferOwnership);

void* getStruct();

this(GstFlowCombiner* gstFlowCombiner, bool ownedRef);

~this();

static GType getType();

this();

void addPad(Pad pad);

void clear();

void free();

alias doref = ref_;

FlowCombiner ref_();

void removePad(Pad pad);

void reset();

void unref();

GstFlowReturn updateFlow(GstFlowReturn fret);

GstFlowReturn updatePadFlow(Pad pad, GstFlowReturn fret);

}

Constructors

this this(GstFlowCombiner* gstFlowCombiner, bool ownedRef): Sets our main struct and passes it to the parent class.
this this(): Creates a new #GstFlowCombiner, use gst_flow_combiner_free() to free it.

Destructor

~this ~this(): Undocumented in source.

Members

Aliases

doref alias doref = ref_: Undocumented in source.

Functions

addPad void addPad(Pad pad): Adds a new #GstPad to the #GstFlowCombiner.
clear void clear(): Removes all pads from a #GstFlowCombiner and resets it to its initial state.
free void free(): Frees a #GstFlowCombiner struct and all its internal data.
getFlowCombinerStruct GstFlowCombiner* getFlowCombinerStruct(bool transferOwnership): Get the main Gtk struct
getStruct void* getStruct(): the main Gtk struct as a void*
ref_ FlowCombiner ref_(): Increments the reference count on the #GstFlowCombiner.
removePad void removePad(Pad pad): Removes a #GstPad from the #GstFlowCombiner.
reset void reset(): Reset flow combiner and all pads to their initial state without removing pads.
unref void unref(): Decrements the reference count on the #GstFlowCombiner.
updateFlow GstFlowReturn updateFlow(GstFlowReturn fret): Computes the combined flow return for the pads in it.
updatePadFlow GstFlowReturn updatePadFlow(Pad pad, GstFlowReturn fret): Sets the provided pad's last flow return to provided value and computes the combined flow return for the pads in it.

Static functions

getType GType getType()

Variables

gstFlowCombiner GstFlowCombiner* gstFlowCombiner;: the main Gtk struct
ownedRef bool ownedRef;: Undocumented in source.