GstPadTemplate

Padtemplates describe the possible media types a pad or an elementfactory can handle. This allows for both inspection of handled types before loading the element plugin as well as identifying pads on elements that are not yet created (request or sometimes pads).

Pad and PadTemplates have GstCaps attached to it to describe the media type they are capable of dealing with. gst_pad_template_get_caps or GST_PAD_TEMPLATE_CAPS are used to get the caps of a padtemplate. It's not possible to modify the caps of a padtemplate after creation.

PadTemplates have a GstPadPresence property which identifies the lifetime of the pad and that can be retrieved with GST_PAD_TEMPLATE_PRESENCE. Also the direction of the pad can be retrieved from the GstPadTemplate with GST_PAD_TEMPLATE_DIRECTION.

The GST_PAD_TEMPLATE_NAME_TEMPLATE () is important for GST_PAD_REQUEST pads because it has to be used as the name in the gst_element_request_pad_simple call to instantiate a pad from this template.

Padtemplates can be created with gst_pad_template_new or with gst_static_pad_template_get (), which creates a GstPadTemplate from a GstStaticPadTemplate that can be filled with the convenient GST_STATIC_PAD_TEMPLATE macro.

A padtemplate can be used to create a pad (see gst_pad_new_from_template or gst_pad_new_from_static_template ()) or to add to an element class (see gst_element_class_add_static_pad_template ()).

The following code example shows the code to create a pad from a padtemplate.

   GstStaticPadTemplate my_template =
   GST_STATIC_PAD_TEMPLATE (
     "sink",          // the name of the pad
     GST_PAD_SINK,    // the direction of the pad
     GST_PAD_ALWAYS,  // when this pad will be present
     GST_STATIC_CAPS (        // the capabilities of the padtemplate
       "audio/x-raw, "
         "channels = (int) [ 1, 6 ]"
     )
   );
   void
   my_method (void)
   {
     GstPad *pad;
     pad = gst_pad_new_from_static_template (&my_template, "sink");
     ...
   }

The following example shows you how to add the padtemplate to an element class, this is usually done in the class_init of the class:

   static void
   my_element_class_init (GstMyElementClass *klass)
   {
     GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);

     gst_element_class_add_static_pad_template (gstelement_class, &my_template);
   }

GstPadTemplate

GObject
    ╰──GInitiallyUnowned
        ╰──GstObject
            ╰──GstPadTemplate

The padtemplate object.

Members

object (GstObject) –

No description available

name_template (gchar *) –

No description available

direction (GstPadDirection) –

No description available

presence (GstPadPresence) –

No description available

caps (GstCaps *) –

No description available

ABI._gst_reserved (gpointer *) –

No description available

ABI.abi.gtype (GType) –

No description available

ABI.abi.documentation_caps (GstCaps *) –

No description available

Class structure

GstPadTemplateClass

Fields

parent_class (GstObjectClass) –

No description available

Gst.PadTemplateClass

Attributes

parent_class (Gst.ObjectClass) –

No description available

Gst.PadTemplateClass

Attributes

parent_class (Gst.ObjectClass) –

No description available

Gst.PadTemplate

GObject.Object
    ╰──GObject.InitiallyUnowned
        ╰──Gst.Object
            ╰──Gst.PadTemplate

The padtemplate object.

Members

object (Gst.Object) –

No description available

name_template (String) –

No description available

direction (Gst.PadDirection) –

No description available

presence (Gst.PadPresence) –

No description available

caps (Gst.Caps) –

No description available

Gst.PadTemplate

GObject.Object
    ╰──GObject.InitiallyUnowned
        ╰──Gst.Object
            ╰──Gst.PadTemplate

The padtemplate object.

Members

object (Gst.Object) –

No description available

name_template (str) –

No description available

direction (Gst.PadDirection) –

No description available

presence (Gst.PadPresence) –

No description available

caps (Gst.Caps) –

No description available

Constructors

gst_pad_template_new

GstPadTemplate *
gst_pad_template_new (const gchar * name_template,
                      GstPadDirection direction,
                      GstPadPresence presence,
                      GstCaps * caps)

Creates a new pad template with a name according to the given template and with the given arguments.

Parameters:

name_template –

the name template.

direction –

the GstPadDirection of the template.

presence –

the GstPadPresence of the pad.

caps ( [transfer: none]) –

a GstCaps set for the template.

Returns ( [transfer: floating][nullable]) –

a new GstPadTemplate.

Gst.PadTemplate.prototype.new

function Gst.PadTemplate.prototype.new(name_template: String, direction: Gst.PadDirection, presence: Gst.PadPresence, caps: Gst.Caps): {
    // javascript wrapper for 'gst_pad_template_new'
}

Creates a new pad template with a name according to the given template and with the given arguments.

Parameters:

name_template (String) –

the name template.

direction (Gst.PadDirection) –

the Gst.PadDirection of the template.

presence (Gst.PadPresence) –

the Gst.PadPresence of the pad.

caps (Gst.Caps) –

a Gst.Caps set for the template.

Returns (Gst.PadTemplate) –

a new Gst.PadTemplate.

Gst.PadTemplate.new

def Gst.PadTemplate.new (name_template, direction, presence, caps):
    #python wrapper for 'gst_pad_template_new'

Creates a new pad template with a name according to the given template and with the given arguments.

Parameters:

name_template (str) –

the name template.

direction (Gst.PadDirection) –

the Gst.PadDirection of the template.

presence (Gst.PadPresence) –

the Gst.PadPresence of the pad.

caps (Gst.Caps) –

a Gst.Caps set for the template.

Returns (Gst.PadTemplate) –

a new Gst.PadTemplate.

gst_pad_template_new_from_static_pad_template_with_gtype

GstPadTemplate *
gst_pad_template_new_from_static_pad_template_with_gtype (GstStaticPadTemplate * pad_template,
                                                          GType pad_type)

Converts a GstStaticPadTemplate into a GstPadTemplate with a type.

Parameters:

pad_template –

the static pad template

pad_type –

The GType of the pad to create

Returns ( [transfer: floating][nullable]) –

a new GstPadTemplate.

Since : 1.14

Gst.PadTemplate.prototype.new_from_static_pad_template_with_gtype

function Gst.PadTemplate.prototype.new_from_static_pad_template_with_gtype(pad_template: Gst.StaticPadTemplate, pad_type: GObject.Type): {
    // javascript wrapper for 'gst_pad_template_new_from_static_pad_template_with_gtype'
}

Converts a Gst.StaticPadTemplate into a Gst.PadTemplate with a type.

Parameters:

pad_template (Gst.StaticPadTemplate) –

the static pad template

pad_type (GObject.Type) –

The GObject.Type of the pad to create

Returns (Gst.PadTemplate) –

a new Gst.PadTemplate.

Since : 1.14

Gst.PadTemplate.new_from_static_pad_template_with_gtype

def Gst.PadTemplate.new_from_static_pad_template_with_gtype (pad_template, pad_type):
    #python wrapper for 'gst_pad_template_new_from_static_pad_template_with_gtype'

Converts a Gst.StaticPadTemplate into a Gst.PadTemplate with a type.

Parameters:

pad_template (Gst.StaticPadTemplate) –

the static pad template

pad_type (GObject.Type) –

The GObject.Type of the pad to create

Returns (Gst.PadTemplate) –

a new Gst.PadTemplate.

Since : 1.14

gst_pad_template_new_with_gtype

GstPadTemplate *
gst_pad_template_new_with_gtype (const gchar * name_template,
                                 GstPadDirection direction,
                                 GstPadPresence presence,
                                 GstCaps * caps,
                                 GType pad_type)

Creates a new pad template with a name according to the given template and with the given arguments.

Parameters:

name_template –

the name template.

direction –

the GstPadDirection of the template.

presence –

the GstPadPresence of the pad.

caps ( [transfer: none]) –

a GstCaps set for the template.

pad_type –

The GType of the pad to create

Returns ( [transfer: floating][nullable]) –

a new GstPadTemplate.

Since : 1.14

Gst.PadTemplate.prototype.new_with_gtype

function Gst.PadTemplate.prototype.new_with_gtype(name_template: String, direction: Gst.PadDirection, presence: Gst.PadPresence, caps: Gst.Caps, pad_type: GObject.Type): {
    // javascript wrapper for 'gst_pad_template_new_with_gtype'
}

Creates a new pad template with a name according to the given template and with the given arguments.

Parameters:

name_template (String) –

the name template.

direction (Gst.PadDirection) –

the Gst.PadDirection of the template.

presence (Gst.PadPresence) –

the Gst.PadPresence of the pad.

caps (Gst.Caps) –

a Gst.Caps set for the template.

pad_type (GObject.Type) –

The GObject.Type of the pad to create

Returns (Gst.PadTemplate) –

a new Gst.PadTemplate.

Since : 1.14

Gst.PadTemplate.new_with_gtype

def Gst.PadTemplate.new_with_gtype (name_template, direction, presence, caps, pad_type):
    #python wrapper for 'gst_pad_template_new_with_gtype'

Creates a new pad template with a name according to the given template and with the given arguments.

Parameters:

name_template (str) –

the name template.

direction (Gst.PadDirection) –

the Gst.PadDirection of the template.

presence (Gst.PadPresence) –

the Gst.PadPresence of the pad.

caps (Gst.Caps) –

a Gst.Caps set for the template.

pad_type (GObject.Type) –

The GObject.Type of the pad to create

Returns (Gst.PadTemplate) –

a new Gst.PadTemplate.

Since : 1.14

Methods

gst_pad_template_get_caps

GstCaps *
gst_pad_template_get_caps (GstPadTemplate * templ)

Gets the capabilities of the pad template.

Parameters:

templ –

a GstPadTemplate to get capabilities of.

Returns ( [transfer: full]) –

the GstCaps of the pad template. Unref after usage.

Gst.PadTemplate.prototype.get_caps

function Gst.PadTemplate.prototype.get_caps(): {
    // javascript wrapper for 'gst_pad_template_get_caps'
}

Gets the capabilities of the pad template.

Parameters:

templ (Gst.PadTemplate) –

a Gst.PadTemplate to get capabilities of.

Returns (Gst.Caps) –

the Gst.Caps of the pad template. Unref after usage.

Gst.PadTemplate.get_caps

def Gst.PadTemplate.get_caps (self):
    #python wrapper for 'gst_pad_template_get_caps'

Gets the capabilities of the pad template.

Parameters:

templ (Gst.PadTemplate) –

a Gst.PadTemplate to get capabilities of.

Returns (Gst.Caps) –

the Gst.Caps of the pad template. Unref after usage.

gst_pad_template_get_documentation_caps

GstCaps *
gst_pad_template_get_documentation_caps (GstPadTemplate * templ)

See gst_pad_template_set_documentation_caps.

Parameters:

templ –

the pad template to get documented capabilities on

Returns ( [transfer: full]) –

The caps to document. For convenience, this will return gst_pad_template_get_caps when no documentation caps were set.

Since : 1.18

Gst.PadTemplate.prototype.get_documentation_caps

function Gst.PadTemplate.prototype.get_documentation_caps(): {
    // javascript wrapper for 'gst_pad_template_get_documentation_caps'
}

See Gst.PadTemplate.prototype.set_documentation_caps.

Parameters:

templ (Gst.PadTemplate) –

the pad template to get documented capabilities on

Returns (Gst.Caps) –

The caps to document. For convenience, this will return Gst.PadTemplate.prototype.get_caps when no documentation caps were set.

Since : 1.18

Gst.PadTemplate.get_documentation_caps

def Gst.PadTemplate.get_documentation_caps (self):
    #python wrapper for 'gst_pad_template_get_documentation_caps'

See Gst.PadTemplate.set_documentation_caps.

Parameters:

templ (Gst.PadTemplate) –

the pad template to get documented capabilities on

Returns (Gst.Caps) –

The caps to document. For convenience, this will return Gst.PadTemplate.get_caps when no documentation caps were set.

Since : 1.18

gst_pad_template_pad_created

gst_pad_template_pad_created (GstPadTemplate * templ,
                              GstPad * pad)

Emit the pad-created signal for this template when created by this pad.

Parameters:

templ –

a GstPadTemplate that has been created

pad –

the GstPad that created it

Gst.PadTemplate.prototype.pad_created

function Gst.PadTemplate.prototype.pad_created(pad: Gst.Pad): {
    // javascript wrapper for 'gst_pad_template_pad_created'
}

Emit the pad-created signal for this template when created by this pad.

Parameters:

templ (Gst.PadTemplate) –

a Gst.PadTemplate that has been created

pad (Gst.Pad) –

the Gst.Pad that created it

Gst.PadTemplate.pad_created

def Gst.PadTemplate.pad_created (self, pad):
    #python wrapper for 'gst_pad_template_pad_created'

Emit the pad-created signal for this template when created by this pad.

Parameters:

templ (Gst.PadTemplate) –

a Gst.PadTemplate that has been created

pad (Gst.Pad) –

the Gst.Pad that created it

gst_pad_template_set_documentation_caps

gst_pad_template_set_documentation_caps (GstPadTemplate * templ,
                                         GstCaps * caps)

Certain elements will dynamically construct the caps of their pad templates. In order not to let environment-specific information into the documentation, element authors should use this method to expose "stable" caps to the reader.

Parameters:

templ –

the pad template to set documented capabilities on

caps ( [transfer: none]) –

the documented capabilities

Since : 1.18

Gst.PadTemplate.prototype.set_documentation_caps

function Gst.PadTemplate.prototype.set_documentation_caps(caps: Gst.Caps): {
    // javascript wrapper for 'gst_pad_template_set_documentation_caps'
}

Parameters:

templ (Gst.PadTemplate) –

the pad template to set documented capabilities on

caps (Gst.Caps) –

the documented capabilities

Since : 1.18

Gst.PadTemplate.set_documentation_caps

def Gst.PadTemplate.set_documentation_caps (self, caps):
    #python wrapper for 'gst_pad_template_set_documentation_caps'

Parameters:

templ (Gst.PadTemplate) –

the pad template to set documented capabilities on

caps (Gst.Caps) –

the documented capabilities

Since : 1.18

Signals

pad-created

pad_created_callback (GstPadTemplate * self,
                      GstPad * pad,
                      gpointer user_data)

This signal is fired when an element creates a pad from this template.

Parameters:

self –

No description available

pad –

the pad that was created.

user_data –

No description available

Flags: Run Last

pad-created

function pad_created_callback(self: Gst.PadTemplate, pad: Gst.Pad, user_data: Object): {
    // javascript callback for the 'pad-created' signal
}

This signal is fired when an element creates a pad from this template.

Parameters:

self (Gst.PadTemplate) –

No description available

pad (Gst.Pad) –

the pad that was created.

user_data (Object) –

No description available

Flags: Run Last

pad-created

def pad_created_callback (self, pad, *user_data):
    #python callback for the 'pad-created' signal

This signal is fired when an element creates a pad from this template.

Parameters:

self (Gst.PadTemplate) –

No description available

pad (Gst.Pad) –

the pad that was created.

user_data (variadic) –

No description available

Flags: Run Last