Gst::Fourcc Class Reference

A class that represents a 4 byte identifier (used in codecs). More...

#include <gstreamermm/value.h>

Public Member Functions
	Fourcc ()
	Construct an undefined Gst::Fourcc. More...
	Fourcc (const Fourcc& src)
	Construct a Gst::Fourcc from another. More...
	Fourcc (char first, char second, char third, char fourth)
	Construct a Gst::Fourcc from 4 characters. More...
	Fourcc (const Glib::ustring& s)
	Construct a Gst::Fourcc from an input string. More...
	Fourcc (guint32 fourcc)
	Construct a Gst::Fourcc from a 32 bit unsigned integer. More...
Fourcc&	operator= (const Fourcc& src)

Public Attributes
char	first
char	second
char	third
char	fourth

Detailed Description

A class that represents a 4 byte identifier (used in codecs).

Gst::Fourcc is used to store a four byte identifier in Gst::Structure of Gst::Caps as a value representing a property (see GStreamer Application Development Manual section 8.2.2 and GstValue docs). When the value is set, it is transformed to a GStreamer GType so retrieving the value is a bit different. The class can be used in setting and getting a Gst::Structure field like so:

Glib::Value<Gst::Fourcc> value;
value.init(Glib::Value<Gst::Fourcc>::value_type());
value.set(Gst::Fourcc('M', 'J', 'P', 'G'));

Gst::Structure structure("my-structure");
structure.set_field("id", value);
...
Glib::ValueBase gst_value;
structure.get_field("id", gst_value);
Gst::Fourcc fourcc(gst_value);
char first_char = fourcc.first;
...

Last reviewed on 2016-08-27 (1.8.0)

Constructor & Destructor Documentation

Fourcc() [1/5]

Gst::Fourcc::Fourcc

(

)

Construct an undefined Gst::Fourcc.

Fourcc() [2/5]

Gst::Fourcc::Fourcc

(

const Fourcc&

src

)

Construct a Gst::Fourcc from another.

Fourcc() [3/5]

Gst::Fourcc::Fourcc	(	char	first,
		char	second,
		char	third,
		char	fourth
	)

Construct a Gst::Fourcc from 4 characters.

Fourcc() [4/5]

Gst::Fourcc::Fourcc ( const Glib::ustring &  s )

explicit

Construct a Gst::Fourcc from an input string.

Caller is responsible for ensuring the input string consists of at least four characters.

Fourcc() [5/5]

Gst::Fourcc::Fourcc ( guint32  fourcc )

explicit

Construct a Gst::Fourcc from a 32 bit unsigned integer.

Member Function Documentation

operator=()

Fourcc& Gst::Fourcc::operator=

(

const Fourcc&

src

)

Member Data Documentation

first

char Gst::Fourcc::first

fourth

char Gst::Fourcc::fourth

second

char Gst::Fourcc::second

third

char Gst::Fourcc::third