*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 02111-1307, USA.
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
*/
/**
* SECTION:gstcontrolsource
+ * @title: GstControlSource
* @short_description: base class for control source sources
*
* The #GstControlSource is a base class for control value sources that could
- * be used by #GstController to get timestamp-value pairs.
- *
- * A #GstControlSource is used by first getting an instance, binding it to a
- * #GParamSpec (for example by using gst_controller_set_control_source()) and
- * then by having it used by the #GstController or calling
- * gst_control_source_get_value() or gst_control_source_get_value_array().
- *
- * For implementing a new #GstControlSource one has to implement a
- * #GstControlSourceBind method, which will depending on the #GParamSpec set up
- * the control source for use and sets the #GstControlSourceGetValue and
- * #GstControlSourceGetValueArray functions. These are then used by
- * gst_control_source_get_value() or gst_control_source_get_value_array()
- * to get values for specific timestamps.
- *
+ * be used to get timestamp-value pairs. A control source essentially is a
+ * function over time.
+ *
+ * A #GstControlSource is used by first getting an instance of a specific
+ * control-source, creating a binding for the control-source to the target property
+ * of the element and then adding the binding to the element. The binding will
+ * convert the data types and value range to fit to the bound property.
+ *
+ * For implementing a new #GstControlSource one has to implement
+ * #GstControlSourceGetValue and #GstControlSourceGetValueArray functions.
+ * These are then used by gst_control_source_get_value() and
+ * gst_control_source_get_value_array() to get values for specific timestamps.
*/
#include "gst_private.h"
#define GST_CAT_DEFAULT control_source_debug
GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
-G_DEFINE_ABSTRACT_TYPE (GstControlSource, gst_control_source, G_TYPE_OBJECT);
+#define _do_init \
+ GST_DEBUG_CATEGORY_INIT (GST_CAT_DEFAULT, "gstcontrolsource", 0, \
+ "dynamic parameter control sources");
-static GObjectClass *parent_class = NULL;
+G_DEFINE_ABSTRACT_TYPE_WITH_CODE (GstControlSource, gst_control_source,
+ GST_TYPE_OBJECT, _do_init);
static void
gst_control_source_class_init (GstControlSourceClass * klass)
{
- //GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
-
- parent_class = g_type_class_peek_parent (klass);
-
- /* Has to be implemented by children */
- klass->bind = NULL;
-
- GST_DEBUG_CATEGORY_INIT (GST_CAT_DEFAULT, "gstcontrolsource", 0,
- "dynamic parameter control sources");
}
static void
gst_control_source_init (GstControlSource * self)
{
- /* Set default handlers that print a warning */
self->get_value = NULL;
self->get_value_array = NULL;
- self->bound = FALSE;
}
/**
- * gst_control_source_get_value:
+ * gst_control_source_get_value: (method)
* @self: the #GstControlSource object
* @timestamp: the time for which the value should be returned
- * @value: the value
+ * @value: (out): the value
*
* Gets the value for this #GstControlSource at a given timestamp.
*
- * Returns: FALSE if the value couldn't be returned, TRUE otherwise.
+ * Returns: %FALSE if the value couldn't be returned, %TRUE otherwise.
*/
gboolean
gst_control_source_get_value (GstControlSource * self, GstClockTime timestamp,
- GValue * value)
+ gdouble * value)
{
g_return_val_if_fail (GST_IS_CONTROL_SOURCE (self), FALSE);
}
/**
- * gst_control_source_get_value_array:
+ * gst_control_source_get_value_array: (method)
* @self: the #GstControlSource object
- * @timestamp: the time that should be processed
- * @value_array: array to put control-values in
- *
- * Gets an array of values for one element property.
+ * @timestamp: the first timestamp
+ * @interval: the time steps
+ * @n_values: the number of values to fetch
+ * @values: (array length=n_values): array to put control-values in
*
- * All fields of @value_array must be filled correctly. Especially the
- * @value_array->values array must be big enough to keep the requested amount
- * of values.
- *
- * The type of the values in the array is the same as the property's type.
+ * Gets an array of values for for this #GstControlSource. Values that are
+ * undefined contain NANs.
*
* Returns: %TRUE if the given array could be filled, %FALSE otherwise
*/
gboolean
gst_control_source_get_value_array (GstControlSource * self,
- GstClockTime timestamp, GstValueArray * value_array)
+ GstClockTime timestamp, GstClockTime interval, guint n_values,
+ gdouble * values)
{
g_return_val_if_fail (GST_IS_CONTROL_SOURCE (self), FALSE);
if (G_LIKELY (self->get_value_array)) {
- return self->get_value_array (self, timestamp, value_array);
+ return self->get_value_array (self, timestamp, interval, n_values, values);
} else {
GST_ERROR ("Not bound to a specific property yet!");
return FALSE;
}
}
-
-/**
- * gst_control_source_bind:
- * @self: the #GstControlSource object
- * @pspec: #GParamSpec for the property for which this #GstControlSource should generate values.
- *
- * Binds a #GstControlSource to a specific property. This must be called only once for a
- * #GstControlSource.
- *
- * Returns: %TRUE if the #GstControlSource was bound correctly, %FALSE otherwise.
- */
-gboolean
-gst_control_source_bind (GstControlSource * self, GParamSpec * pspec)
-{
- gboolean ret = FALSE;
-
- g_return_val_if_fail (GST_IS_CONTROL_SOURCE (self), FALSE);
- g_return_val_if_fail (GST_CONTROL_SOURCE_GET_CLASS (self)->bind, FALSE);
- g_return_val_if_fail (!self->bound, FALSE);
-
- ret = GST_CONTROL_SOURCE_GET_CLASS (self)->bind (self, pspec);
-
- if (ret)
- self->bound = TRUE;
-
- return ret;
-}
projects / platform / upstream / gstreamer.git / blobdiff