--- /dev/null
+/* GStreamer Color Balance
+ * Copyright (C) 2003 Ronald Bultje <rbultje@ronald.bitfreak.net>
+ *
+ * colorbalance.c: image color balance interface design
+ * virtual class function wrappers
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Library General Public License for more details.
+ *
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "colorbalance.h"
+#include "interfaces-marshal.h"
+
+/**
+ * SECTION:gstcolorbalance
+ * @short_description: Interface for adjusting color balance settings
+ *
+ * <refsect2><para>
+ * This interface is implemented by elements which can perform some color
+ * balance operation on video frames they process. For example, modifying
+ * the brightness, contrast, hue or saturation.
+ * </para><para>
+ * Example elements are 'xvimagesink' and 'colorbalance'
+ * </para>
+ * </refsect2>
+ */
+
+enum
+{
+ VALUE_CHANGED,
+ LAST_SIGNAL
+};
+
+static void gst_color_balance_class_init (GstColorBalanceClass * klass);
+
+static guint gst_color_balance_signals[LAST_SIGNAL] = { 0 };
+
+GType
+gst_color_balance_get_type (void)
+{
+ static GType gst_color_balance_type = 0;
+
+ if (!gst_color_balance_type) {
+ static const GTypeInfo gst_color_balance_info = {
+ sizeof (GstColorBalanceClass),
+ (GBaseInitFunc) gst_color_balance_class_init,
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+ 0,
+ 0,
+ NULL,
+ };
+
+ gst_color_balance_type = g_type_register_static (G_TYPE_INTERFACE,
+ "GstColorBalance", &gst_color_balance_info, 0);
+ g_type_interface_add_prerequisite (gst_color_balance_type,
+ GST_TYPE_IMPLEMENTS_INTERFACE);
+ }
+
+ return gst_color_balance_type;
+}
+
+static void
+gst_color_balance_class_init (GstColorBalanceClass * klass)
+{
+ static gboolean initialized = FALSE;
+
+ if (!initialized) {
+ /**
+ * GstColorBalance::value-changed:
+ * @colorbalance: The GstColorBalance instance
+ * @channel: The #GstColorBalanceChannel
+ * @value: The new value
+ *
+ * Fired when the value of the indicated channel has changed.
+ */
+ gst_color_balance_signals[VALUE_CHANGED] =
+ g_signal_new ("value-changed",
+ GST_TYPE_COLOR_BALANCE, G_SIGNAL_RUN_LAST,
+ G_STRUCT_OFFSET (GstColorBalanceClass, value_changed),
+ NULL, NULL,
+ gst_interfaces_marshal_VOID__OBJECT_INT,
+ G_TYPE_NONE, 2, GST_TYPE_COLOR_BALANCE_CHANNEL, G_TYPE_INT);
+
+ initialized = TRUE;
+ }
+
+ klass->balance_type = GST_COLOR_BALANCE_SOFTWARE;
+
+ /* default virtual functions */
+ klass->list_channels = NULL;
+ klass->set_value = NULL;
+ klass->get_value = NULL;
+}
+
+/**
+ * gst_color_balance_list_channels:
+ * @balance: A #GstColorBalance instance
+ *
+ * Retrieve a list of the available channels.
+ *
+ * Returns: A GList containing pointers to #GstColorBalanceChannel objects.
+ * The list is owned by the #GstColorBalance instance and must not
+ * be freed.
+ */
+const GList *
+gst_color_balance_list_channels (GstColorBalance * balance)
+{
+ GstColorBalanceClass *klass = GST_COLOR_BALANCE_GET_CLASS (balance);
+
+ if (klass->list_channels) {
+ return klass->list_channels (balance);
+ }
+
+ return NULL;
+}
+
+/**
+ * gst_color_balance_set_value:
+ * @balance: A #GstColorBalance instance
+ * @channel: A #GstColorBalanceChannel instance
+ * @value: The new value for the channel.
+ *
+ * Sets the current value of the channel to the passed value, which must
+ * be between min_value and max_value.
+ *
+ * See Also: The #GstColorBalanceChannel::min_value and
+ * #GstColorBalanceChannel::max_value members of the
+ * #GstColorBalanceChannel object.
+ */
+void
+gst_color_balance_set_value (GstColorBalance * balance,
+ GstColorBalanceChannel * channel, gint value)
+{
+ GstColorBalanceClass *klass = GST_COLOR_BALANCE_GET_CLASS (balance);
+
+ if (klass->set_value) {
+ klass->set_value (balance, channel, value);
+ }
+}
+
+/**
+ * gst_color_balance_get_value:
+ * @balance: A #GstColorBalance instance
+ * @channel: A #GstColorBalanceChannel instance
+ *
+ * Retrieve the current value of the indicated channel, between min_value
+ * and max_value.
+ *
+ * See Also: The #GstColorBalanceChannel::min_value and
+ * #GstColorBalanceChannel::max_value members of the
+ * #GstColorBalanceChannel object.
+ *
+ * Returns: The current value of the channel.
+ */
+gint
+gst_color_balance_get_value (GstColorBalance * balance,
+ GstColorBalanceChannel * channel)
+{
+ GstColorBalanceClass *klass = GST_COLOR_BALANCE_GET_CLASS (balance);
+
+ if (klass->get_value) {
+ return klass->get_value (balance, channel);
+ }
+
+ return channel->min_value;
+}
+
+/**
+ * gst_color_balance_get_balance_type:
+ * @balance: The #GstColorBalance implementation
+ *
+ * Get the #GstColorBalanceType of this implementation.
+ *
+ * Returns: A the #GstColorBalanceType.
+ *
+ * Since: 0.10.24
+ */
+GstColorBalanceType
+gst_color_balance_get_balance_type (GstColorBalance * balance)
+{
+ GstColorBalanceClass *klass = GST_COLOR_BALANCE_GET_CLASS (balance);
+
+ return klass->balance_type;
+}
+
+/**
+ * gst_color_balance_value_changed:
+ * @balance: A #GstColorBalance instance
+ * @channel: A #GstColorBalanceChannel whose value has changed
+ * @value: The new value of the channel
+ *
+ * A helper function called by implementations of the GstColorBalance
+ * interface. It fires the #GstColorBalance::value-changed signal on the
+ * instance, and the #GstColorBalanceChannel::value-changed signal on the
+ * channel object.
+ */
+void
+gst_color_balance_value_changed (GstColorBalance * balance,
+ GstColorBalanceChannel * channel, gint value)
+{
+ g_signal_emit (G_OBJECT (balance),
+ gst_color_balance_signals[VALUE_CHANGED], 0, channel, value);
+
+ g_signal_emit_by_name (G_OBJECT (channel), "value_changed", value);
+}