1 /* GStreamer
2  *
3  * Copyright (C) 2003 Ronald Bultje <rbultje@ronald.bitfreak.net>
4  *               2006 Edgard Lima <edgard.lima@gmail.com>
5  *
6  * gstv4l2colorbalance.c: color balance interface implementation for V4L2
7  *
8  * This library is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Library General Public
10  * License as published by the Free Software Foundation; either
11  * version 2 of the License, or (at your option) any later version.
12  *
13  * This library is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * Library General Public License for more details.
17  *
18  * You should have received a copy of the GNU Library General Public
19  * License along with this library; if not, write to the
20  * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
21  * Boston, MA 02110-1301, USA.
22  */
23 
24 #ifdef HAVE_CONFIG_H
25 #include "config.h"
26 #endif
27 
28 #include <gst/gst.h>
29 #include "gstv4l2colorbalance.h"
30 #include "gstv4l2object.h"
31 
32 #define gst_v4l2_color_balance_channel_parent_class parent_class
33 G_DEFINE_TYPE (GstV4l2ColorBalanceChannel,
34     gst_v4l2_color_balance_channel, GST_TYPE_COLOR_BALANCE_CHANNEL);
35 
36 static void
gst_v4l2_color_balance_channel_class_init(GstV4l2ColorBalanceChannelClass * klass)37 gst_v4l2_color_balance_channel_class_init (GstV4l2ColorBalanceChannelClass *
38     klass)
39 {
40 }
41 
42 static void
gst_v4l2_color_balance_channel_init(GstV4l2ColorBalanceChannel * channel)43 gst_v4l2_color_balance_channel_init (GstV4l2ColorBalanceChannel * channel)
44 {
45   channel->id = (guint32) - 1;
46 }
47 
48 static G_GNUC_UNUSED gboolean
gst_v4l2_color_balance_contains_channel(GstV4l2Object * v4l2object,GstV4l2ColorBalanceChannel * v4l2channel)49 gst_v4l2_color_balance_contains_channel (GstV4l2Object * v4l2object,
50     GstV4l2ColorBalanceChannel * v4l2channel)
51 {
52   const GList *item;
53 
54   for (item = v4l2object->colors; item != NULL; item = item->next)
55     if (item->data == v4l2channel)
56       return TRUE;
57 
58   return FALSE;
59 }
60 
61 const GList *
gst_v4l2_color_balance_list_channels(GstV4l2Object * v4l2object)62 gst_v4l2_color_balance_list_channels (GstV4l2Object * v4l2object)
63 {
64   return v4l2object->colors;
65 }
66 
67 void
gst_v4l2_color_balance_set_value(GstV4l2Object * v4l2object,GstColorBalanceChannel * channel,gint value)68 gst_v4l2_color_balance_set_value (GstV4l2Object * v4l2object,
69     GstColorBalanceChannel * channel, gint value)
70 {
71 
72   GstV4l2ColorBalanceChannel *v4l2channel =
73       GST_V4L2_COLOR_BALANCE_CHANNEL (channel);
74 
75   /* assert that we're opened and that we're using a known item */
76   g_return_if_fail (GST_V4L2_IS_OPEN (v4l2object));
77   g_return_if_fail (gst_v4l2_color_balance_contains_channel (v4l2object,
78           v4l2channel));
79 
80   gst_v4l2_set_attribute (v4l2object, v4l2channel->id, value);
81 }
82 
83 gint
gst_v4l2_color_balance_get_value(GstV4l2Object * v4l2object,GstColorBalanceChannel * channel)84 gst_v4l2_color_balance_get_value (GstV4l2Object * v4l2object,
85     GstColorBalanceChannel * channel)
86 {
87   GstV4l2ColorBalanceChannel *v4l2channel =
88       GST_V4L2_COLOR_BALANCE_CHANNEL (channel);
89   gint value;
90 
91   /* assert that we're opened and that we're using a known item */
92   g_return_val_if_fail (GST_V4L2_IS_OPEN (v4l2object), 0);
93   g_return_val_if_fail (gst_v4l2_color_balance_contains_channel (v4l2object,
94           v4l2channel), 0);
95 
96   if (!gst_v4l2_get_attribute (v4l2object, v4l2channel->id, &value))
97     return 0;
98 
99   return value;
100 }
101