gstreamer/sys/v4l2/gstv4l2colorbalance.c
Ronald S. Bultje 862d28a1b7 Some interface implementations for video4linux/video4linux2 plugins: a Tuner interface, with which one can select inp...
Original commit message from CVS:
Some interface implementations for video4linux/video4linux2 plugins:
* a Tuner interface, with which one can select inputs and stations. Audio
work is underway here, but unfinished.
* A Xoverlay interface with which one can do simple overlay. Similar to
the API of the v4l/Xv XFree86 extension. Widget implementation for
GTK-2.0 coming up in the sandbox.
* Colorbalance - for adapting colors (brightness, contrast, etc.) - pretty
basic and maybe somewhat overdesigned. But it'll do for now.

Apart from these interfaces, there's also a loadable library 'xwindowlistener'
that listenes to X for the movement of a window and the overlap of other
windows. This is partly copied from xawtv (and thus partly GPL :(), but it's
needed for the xoverlay interface implementation in the v4l/v4l2 elements.

Lastly, some small changes to remove redundant properties from the v4l/v4l2
elements since these can be done much simpler. Comments appreciated!
2003-10-10 12:47:42 +00:00

151 lines
4.5 KiB
C

/* GStreamer Color Balance interface implementation
* Copyright (C) 2003 Ronald Bultje <rbultje@ronald.bitfreak.net>
*
* gstv4l2colorbalance.c: color balance interface implementation for V4L2
*
* 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 <gst/gst.h>
#include "gstv4l2colorbalance.h"
#include "gstv4l2element.h"
static void
gst_v4l2_color_balance_channel_class_init(GstV4l2ColorBalanceChannelClass *klass);
static void
gst_v4l2_color_balance_channel_init (GstV4l2ColorBalanceChannel *channel);
static const GList *
gst_v4l2_color_balance_list_channels (GstColorBalance *balance);
static void
gst_v4l2_color_balance_set_value (GstColorBalance *balance,
GstColorBalanceChannel *channel,
gint value);
static gint
gst_v4l2_color_balance_get_value (GstColorBalance *balance,
GstColorBalanceChannel *channel);
static GstColorBalanceChannelClass *parent_class = NULL;
GType
gst_v4l2_color_balance_channel_get_type (void)
{
static GType gst_v4l2_color_balance_channel_type = 0;
if (!gst_v4l2_color_balance_channel_type) {
static const GTypeInfo v4l2_tuner_channel_info = {
sizeof (GstV4l2ColorBalanceChannelClass),
NULL,
NULL,
(GClassInitFunc) gst_v4l2_color_balance_channel_class_init,
NULL,
NULL,
sizeof (GstV4l2ColorBalanceChannel),
0,
(GInstanceInitFunc) gst_v4l2_color_balance_channel_init,
NULL
};
gst_v4l2_color_balance_channel_type =
g_type_register_static (GST_TYPE_COLOR_BALANCE_CHANNEL,
"GstV4l2ColorBalanceChannel",
&v4l2_tuner_channel_info, 0);
}
return gst_v4l2_color_balance_channel_type;
}
static void
gst_v4l2_color_balance_channel_class_init (GstV4l2ColorBalanceChannelClass *klass)
{
parent_class = g_type_class_ref (GST_TYPE_COLOR_BALANCE_CHANNEL);
}
static void
gst_v4l2_color_balance_channel_init (GstV4l2ColorBalanceChannel *channel)
{
channel->index = 0;
}
void
gst_v4l2_color_balance_interface_init (GstColorBalanceClass *klass)
{
/* default virtual functions */
klass->list_channels = gst_v4l2_color_balance_list_channels;
klass->set_value = gst_v4l2_color_balance_set_value;
klass->get_value = gst_v4l2_color_balance_get_value;
}
static gboolean
gst_v4l2_color_balance_contains_channel (GstV4l2Element *v4l2element,
GstV4l2ColorBalanceChannel *v4l2channel)
{
const GList *item;
for (item = v4l2element->colors; item != NULL; item = item->next)
if (item->data == v4l2channel)
return TRUE;
return FALSE;
}
static const GList *
gst_v4l2_color_balance_list_channels (GstColorBalance *balance)
{
return GST_V4L2ELEMENT (balance)->colors;
}
static void
gst_v4l2_color_balance_set_value (GstColorBalance *balance,
GstColorBalanceChannel *channel,
gint value)
{
GstV4l2Element *v4l2element = GST_V4L2ELEMENT (balance);
GstV4l2ColorBalanceChannel *v4l2channel =
GST_V4L2_COLOR_BALANCE_CHANNEL (channel);
/* assert that we're opened and that we're using a known item */
g_return_if_fail (GST_V4L2_IS_OPEN (v4l2element));
g_return_if_fail (gst_v4l2_color_balance_contains_channel (v4l2element,
v4l2channel));
gst_v4l2_set_attribute (v4l2element, v4l2channel->index, value);
}
static gint
gst_v4l2_color_balance_get_value (GstColorBalance *balance,
GstColorBalanceChannel *channel)
{
GstV4l2Element *v4l2element = GST_V4L2ELEMENT (balance);
GstV4l2ColorBalanceChannel *v4l2channel =
GST_V4L2_COLOR_BALANCE_CHANNEL (channel);
gint value;
/* assert that we're opened and that we're using a known item */
g_return_val_if_fail (GST_V4L2_IS_OPEN (v4l2element), 0);
g_return_val_if_fail (gst_v4l2_color_balance_contains_channel (v4l2element,
v4l2channel),
0);
if (!gst_v4l2_get_attribute (v4l2element, v4l2channel->index, &value))
return 0;
return value;
}