sys/v4l2/gstv4l2colorbalance.c

   1 /* GStreamer Color Balance interface implementation
   2  * Copyright (C) 2003 Ronald Bultje <rbultje@ronald.bitfreak.net>
   3  *
   4  * gstv4l2colorbalance.c: color balance interface implementation for V4L2
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Library General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Library General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Library General Public
  17  * License along with this library; if not, write to the
  18  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19  * Boston, MA 02111-1307, USA.
  20  */
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include "config.h"
  24 #endif
  25
  26 #include <gst/gst.h>
  27 #include "gstv4l2colorbalance.h"
  28 #include "gstv4l2element.h"
  29
  30 static void
  31 gst_v4l2_color_balance_channel_class_init(GstV4l2ColorBalanceChannelClass *klass);
  32 static void
  33 gst_v4l2_color_balance_channel_init     (GstV4l2ColorBalanceChannel *channel);
  34
  35 static const GList *
  36 gst_v4l2_color_balance_list_channels    (GstColorBalance        *balance);
  37 static void
  38 gst_v4l2_color_balance_set_value        (GstColorBalance        *balance,
  39                                          GstColorBalanceChannel *channel,
  40                                          gint                    value);
  41 static gint
  42 gst_v4l2_color_balance_get_value        (GstColorBalance        *balance,
  43                                          GstColorBalanceChannel *channel);
  44
  45 static GstColorBalanceChannelClass *parent_class = NULL;
  46
  47 GType
  48 gst_v4l2_color_balance_channel_get_type (void)
  49 {
  50   static GType gst_v4l2_color_balance_channel_type = 0;
  51
  52   if (!gst_v4l2_color_balance_channel_type) {
  53     static const GTypeInfo v4l2_tuner_channel_info = {
  54       sizeof (GstV4l2ColorBalanceChannelClass),
  55       NULL,
  56       NULL,
  57       (GClassInitFunc) gst_v4l2_color_balance_channel_class_init,
  58       NULL,
  59       NULL,
  60       sizeof (GstV4l2ColorBalanceChannel),
  61       0,
  62       (GInstanceInitFunc) gst_v4l2_color_balance_channel_init,
  63       NULL
  64     };
  65
  66     gst_v4l2_color_balance_channel_type =
  67         g_type_register_static (GST_TYPE_COLOR_BALANCE_CHANNEL,
  68                                 "GstV4l2ColorBalanceChannel",
  69                                 &v4l2_tuner_channel_info, 0);
  70   }
  71
  72   return gst_v4l2_color_balance_channel_type;
  73 }
  74
  75 static void
  76 gst_v4l2_color_balance_channel_class_init (GstV4l2ColorBalanceChannelClass *klass)
  77 {
  78   parent_class = g_type_class_ref (GST_TYPE_COLOR_BALANCE_CHANNEL);
  79 }
  80
  81 static void
  82 gst_v4l2_color_balance_channel_init (GstV4l2ColorBalanceChannel *channel)
  83 {
  84   channel->index = 0;
  85 }
  86
  87 void
  88 gst_v4l2_color_balance_interface_init (GstColorBalanceClass *klass)
  89 {
  90   GST_COLOR_BALANCE_TYPE (klass) = GST_COLOR_BALANCE_HARDWARE;
  91
  92   /* default virtual functions */
  93   klass->list_channels = gst_v4l2_color_balance_list_channels;
  94   klass->set_value = gst_v4l2_color_balance_set_value;
  95   klass->get_value = gst_v4l2_color_balance_get_value;
  96 }
  97
  98 static gboolean
  99 gst_v4l2_color_balance_contains_channel (GstV4l2Element             *v4l2element,
 100                                          GstV4l2ColorBalanceChannel *v4l2channel)
 101 {
 102   const GList *item;
 103
 104   for (item = v4l2element->colors; item != NULL; item = item->next)
 105     if (item->data == v4l2channel)
 106       return TRUE;
 107
 108   return FALSE;
 109 }
 110
 111 static const GList *
 112 gst_v4l2_color_balance_list_channels (GstColorBalance *balance)
 113 {
 114   return GST_V4L2ELEMENT (balance)->colors;
 115 }
 116
 117 static void
 118 gst_v4l2_color_balance_set_value (GstColorBalance        *balance,
 119                                   GstColorBalanceChannel *channel,
 120                                   gint                    value)
 121 {
 122   GstV4l2Element *v4l2element = GST_V4L2ELEMENT (balance);
 123   GstV4l2ColorBalanceChannel *v4l2channel =
 124         GST_V4L2_COLOR_BALANCE_CHANNEL (channel);
 125
 126   /* assert that we're opened and that we're using a known item */
 127   g_return_if_fail (GST_V4L2_IS_OPEN (v4l2element));
 128   g_return_if_fail (gst_v4l2_color_balance_contains_channel (v4l2element,
 129                                                              v4l2channel));
 130
 131   gst_v4l2_set_attribute (v4l2element, v4l2channel->index, value);
 132 }
 133
 134 static gint
 135 gst_v4l2_color_balance_get_value (GstColorBalance        *balance,
 136                                   GstColorBalanceChannel *channel)
 137 {
 138   GstV4l2Element *v4l2element = GST_V4L2ELEMENT (balance);
 139   GstV4l2ColorBalanceChannel *v4l2channel =
 140         GST_V4L2_COLOR_BALANCE_CHANNEL (channel);
 141   gint value;
 142
 143   /* assert that we're opened and that we're using a known item */
 144   g_return_val_if_fail (GST_V4L2_IS_OPEN (v4l2element), 0);
 145   g_return_val_if_fail (gst_v4l2_color_balance_contains_channel (v4l2element,
 146                                                                  v4l2channel),
 147                         0);
 148
 149   if (!gst_v4l2_get_attribute (v4l2element, v4l2channel->index, &value))
 150     return 0;
 151
 152   return value;
 153 }