First we will examine the code you would be likely to place in a header file (although since the interface to the code is entirely defined by the plugin system, and doesn't depend on reading a header file, this is not crucial.)
Example 3.1. Example Plugin Header File
#include <gst/gst.h> /* Definition of structure storing data for this element. */ typedef struct _GstMyFilter { GstElement element; GstPad *sinkpad, *srcpad; gboolean silent; } GstMyFilter; /* Standard definition defining a class for this element. */ typedef struct _GstMyFilterClass { GstElementClass parent_class; } GstMyFilterClass; /* Standard macros for defining types for this element. */ #define GST_TYPE_MY_FILTER (gst_my_filter_get_type()) #define GST_MY_FILTER(obj) \ (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_MY_FILTER,GstMyFilter)) #define GST_MY_FILTER_CLASS(klass) \ (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_MY_FILTER,GstMyFilterClass)) #define GST_IS_MY_FILTER(obj) \ (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_MY_FILTER)) #define GST_IS_MY_FILTER_CLASS(klass) \ (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_MY_FILTER)) /* Standard function returning type information. */ GType gst_my_filter_get_type (void);
Using this header file, you can use the following macro to setup
the GObject
basics in your source file so
that all functions will be called appropriately:
#include "filter.h" G_DEFINE_TYPE (GstMyFilter, gst_my_filter, GST_TYPE_ELEMENT);