Gst::BaseTransform Class Reference
[gstreamermm Base Classes]

Gst::BaseTransform — Base class for simple transform filters. More...

#include <basetransform.h>

Inheritance diagram for Gst::BaseTransform:

Gst::Element Gst::Object Gst::CapsFilter Gst::Identity GstBase::AudioConvert GstBase::AudioFilter GstBase::AudioResample GstBase::FfmpegColorSpace GstBase::VideoScale GstBase::Volume

List of all members.

Public Member Functions

virtual ~BaseTransform ()
GstBaseTransform* gobj ()
 Provides access to the underlying C GObject.
const GstBaseTransform* gobj () const
 Provides access to the underlying C GObject.
GstBaseTransform* gobj_copy ()
 Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.
bool is_passthrough ()
 See if trans is configured as a passthrough transform.
void set_passthrough (bool passthrough)
 Set passthrough mode for this filter by default.
bool is_in_place ()
 See if trans is configured as a in_place transform.
void set_in_place (bool in_place)
 Determines whether a non-writable buffer will be copied before passing to the transform_ip function.
bool is_qos_enabled ()
 Queries if the transform will handle QoS.
void set_qos_enabled (bool enabled)
 Enable or disable QoS handling in the transform.
void update_qos (double proportion, ClockTimeDiff diff, ClockTime timestamp)
 Set the QoS parameters in the transform.
void set_gap_aware (bool gap_aware)
 If gap_aware is false (the default), output buffers will have the Gst::BUFFER_FLAG_GAP flag unset.
void lock ()
 Obtain a lock to protect the transform function from concurrent access.
void unlock ()
 Release the lock that protects the transform function from concurrent access.
Glib::RefPtr<Gst::Padget_sink_pad () const
 Gives the refptr to the sink Gst::Pad object of the element.
Glib::RefPtr<Gst::Padget_src_pad () const
 Gives the refptr to the source Gst::Pad object of the element.
Glib::PropertyProxy<bool> property_qos ()
 Handle Quality-of-Service events.
Glib::PropertyProxy_ReadOnly
<bool> 
property_qos () const
 Handle Quality-of-Service events.
virtual Glib::RefPtr<Gst::Capstransform_caps_vfunc (PadDirection direction, const Glib::RefPtr<Gst::Caps>& caps)
 Optional.
virtual void fixate_caps_vfunc (PadDirection direction, const Glib::RefPtr<Gst::Caps>& caps, const Glib::RefPtr<Gst::Caps>& othercaps)
 Optional.
virtual FlowReturn transform_vfunc (const Glib::RefPtr<Gst::Buffer>& inbuf, const Glib::RefPtr<Gst::Buffer>& outbuf)
 Optional.
virtual FlowReturn transform_ip_vfunc (const Glib::RefPtr<Gst::Buffer>& buf)
 Required if the element operates in-place.

Related Functions

(Note that these are not member functions.)

Glib::RefPtr<Gst::BaseTransformwrap (GstBaseTransform* object, bool take_copy=false)
 A Glib::wrap() method for this object.


Detailed Description

Gst::BaseTransform — Base class for simple transform filters.

This base class is for filter elements that process data.

It provides for:

Use Cases:

Sub-class settable flags on Gst::BaseTransform


Constructor & Destructor Documentation

virtual Gst::BaseTransform::~BaseTransform (  )  [virtual]


Member Function Documentation

virtual void Gst::BaseTransform::fixate_caps_vfunc ( PadDirection  direction,
const Glib::RefPtr<Gst::Caps>&  caps,
const Glib::RefPtr<Gst::Caps>&  othercaps 
) [virtual]

Optional.

Given the pad in this direction and the given caps, fixate the caps on the other pad.

Glib::RefPtr<Gst::Pad> Gst::BaseTransform::get_sink_pad (  )  const

Gives the refptr to the sink Gst::Pad object of the element.

Glib::RefPtr<Gst::Pad> Gst::BaseTransform::get_src_pad (  )  const

Gives the refptr to the source Gst::Pad object of the element.

const GstBaseTransform* Gst::BaseTransform::gobj (  )  const [inline]

GstBaseTransform* Gst::BaseTransform::gobj (  )  [inline]

GstBaseTransform* Gst::BaseTransform::gobj_copy (  ) 

Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.

Reimplemented from Gst::Element.

Reimplemented in Gst::CapsFilter, Gst::Identity, GstBase::AudioConvert, GstBase::AudioFilter, GstBase::AudioResample, GstBase::FfmpegColorSpace, GstBase::VideoScale, and GstBase::Volume.

bool Gst::BaseTransform::is_in_place (  ) 

See if trans is configured as a in_place transform.

Returns:
true is the transform is configured in in_place mode.
MT safe.

bool Gst::BaseTransform::is_passthrough (  ) 

See if trans is configured as a passthrough transform.

Returns:
true is the transform is configured in passthrough mode.
MT safe.

bool Gst::BaseTransform::is_qos_enabled (  ) 

Queries if the transform will handle QoS.

Returns:
true if QoS is enabled.
MT safe.

Since: 0.10.5.

void Gst::BaseTransform::lock (  ) 

Obtain a lock to protect the transform function from concurrent access.

Glib::PropertyProxy_ReadOnly<bool> Gst::BaseTransform::property_qos (  )  const

Handle Quality-of-Service events.

You rarely need to use properties because there are get_ and set_ methods for almost all of them.

Returns:
A PropertyProxy that allows you to get or set the property of the value, or receive notification when the value of the property changes.

Glib::PropertyProxy<bool> Gst::BaseTransform::property_qos (  ) 

Handle Quality-of-Service events.

You rarely need to use properties because there are get_ and set_ methods for almost all of them.

Returns:
A PropertyProxy that allows you to get or set the property of the value, or receive notification when the value of the property changes.

void Gst::BaseTransform::set_gap_aware ( bool  gap_aware  ) 

If gap_aware is false (the default), output buffers will have the Gst::BUFFER_FLAG_GAP flag unset.

If set to true, the element must handle output buffers with this flag set correctly, i.e. it can assume that the buffer contains neutral data but must unset the flag if the output is no neutral data.

MT safe.

Since: 0.10.16

Parameters:
gap_aware New state.

void Gst::BaseTransform::set_in_place ( bool  in_place  ) 

Determines whether a non-writable buffer will be copied before passing to the transform_ip function.

<itemizedlist> <listitem>Always true if no transform function is implemented.</listitem> <listitem>Always false if ONLY transform function is implemented.</listitem> </itemizedlist>

MT safe.

Parameters:
in_place Boolean value indicating that we would like to operate on in_place buffers.

void Gst::BaseTransform::set_passthrough ( bool  passthrough  ) 

Set passthrough mode for this filter by default.

This is mostly useful for filters that do not care about negotiation.

Always true for filters which don't implement either a transform or transform_ip method.

MT safe.

Parameters:
passthrough Boolean indicating passthrough mode.

void Gst::BaseTransform::set_qos_enabled ( bool  enabled  ) 

Enable or disable QoS handling in the transform.

MT safe.

Since: 0.10.5

Parameters:
enabled New state.

virtual Glib::RefPtr<Gst::Caps> Gst::BaseTransform::transform_caps_vfunc ( PadDirection  direction,
const Glib::RefPtr<Gst::Caps>&  caps 
) [virtual]

Optional.

Given the pad in this direction and the given caps, what caps are allowed on the other pad in this element ?

virtual FlowReturn Gst::BaseTransform::transform_ip_vfunc ( const Glib::RefPtr<Gst::Buffer>&  buf  )  [virtual]

Required if the element operates in-place.

Transform the incoming buffer in-place.

virtual FlowReturn Gst::BaseTransform::transform_vfunc ( const Glib::RefPtr<Gst::Buffer>&  inbuf,
const Glib::RefPtr<Gst::Buffer>&  outbuf 
) [virtual]

Optional.

Given the size of a buffer in the given direction with the given caps, calculate the size in bytes of a buffer on the other pad with the given other caps. The default implementation uses get_unit_size_vfunc() and keeps the number of units the same. Required if the transform is not in-place. Get the size in bytes of one unit for the given caps. Allows the subclass to be notified of the actual caps set. Optional. Called when the element starts processing. Allows opening external resources. Optional. Called when the element stops processing. Allows closing external resources. Optional. Event handler on the sink pad. This function should return TRUE if the base class should forward the event. Required if the element does not operate in-place. Transforms one incoming buffer to one outgoing buffer. The function is allowed to change size/timestamp/duration of the outgoing buffer.

void Gst::BaseTransform::unlock (  ) 

Release the lock that protects the transform function from concurrent access.

void Gst::BaseTransform::update_qos ( double  proportion,
ClockTimeDiff  diff,
ClockTime  timestamp 
)

Set the QoS parameters in the transform.

This function is called internally when a QOS event is received but subclasses can provide custom information when needed.

MT safe.

Since: 0.10.5

Parameters:
proportion The proportion.
diff The diff against the clock.
timestamp The timestamp of the buffer generating the QoS expressed in running_time.


Friends And Related Function Documentation

Glib::RefPtr<Gst::BaseTransform> wrap ( GstBaseTransform *  object,
bool  take_copy = false 
) [related]

A Glib::wrap() method for this object.

Parameters:
object The C instance.
take_copy False if the result should take ownership of the C instance. True if it should take a new copy or ref.
Returns:
A C++ instance that wraps this C instance.


The documentation for this class was generated from the following file:

Generated on Thu Jan 15 09:33:12 2009 for gstreamermm by  doxygen 1.5.7.1