aboutsummaryrefslogtreecommitdiff
path: root/gst-libs/gst/audio/gstaudiometa.c
blob: b0a18459af7f534c587b9360c68f6ccedd34ea07 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
/* GStreamer
 * Copyright (C) <2011> Wim Taymans <wim.taymans@gmail.com>
 *
 * 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., 51 Franklin St, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

#include <string.h>

#include "gstaudiometa.h"

static gboolean
gst_audio_downmix_meta_init (GstMeta * meta, gpointer params,
    GstBuffer * buffer)
{
  GstAudioDownmixMeta *dmeta = (GstAudioDownmixMeta *) meta;

  dmeta->from_position = dmeta->to_position = NULL;
  dmeta->from_channels = dmeta->to_channels = 0;
  dmeta->matrix = NULL;

  return TRUE;
}

static void
gst_audio_downmix_meta_free (GstMeta * meta, GstBuffer * buffer)
{
  GstAudioDownmixMeta *dmeta = (GstAudioDownmixMeta *) meta;

  g_free (dmeta->from_position);
  if (dmeta->matrix) {
    g_free (*dmeta->matrix);
    g_free (dmeta->matrix);
  }
}

static gboolean
gst_audio_downmix_meta_transform (GstBuffer * dest, GstMeta * meta,
    GstBuffer * buffer, GQuark type, gpointer data)
{
  GstAudioDownmixMeta *smeta;

  smeta = (GstAudioDownmixMeta *) meta;
  gst_buffer_add_audio_downmix_meta (dest, smeta->from_position,
      smeta->from_channels, smeta->to_position, smeta->to_channels,
      (const gfloat **) smeta->matrix);

  return TRUE;
}

/**
 * gst_buffer_get_audio_downmix_meta_for_channels:
 * @buffer: a #GstBuffer
 * @to_position: (array length=to_channels): the channel positions of
 *   the destination
 * @to_channels: The number of channels of the destination
 *
 * Find the #GstAudioDownmixMeta on @buffer for the given destination
 * channel positions.
 *
 * Returns: the #GstAudioDownmixMeta on @buffer.
 */
GstAudioDownmixMeta *
gst_buffer_get_audio_downmix_meta_for_channels (GstBuffer * buffer,
    const GstAudioChannelPosition * to_position, gint to_channels)
{
  gpointer state = NULL;
  GstMeta *meta;
  const GstMetaInfo *info = GST_AUDIO_DOWNMIX_META_INFO;

  while ((meta = gst_buffer_iterate_meta (buffer, &state))) {
    if (meta->info->api == info->api) {
      GstAudioDownmixMeta *ameta = (GstAudioDownmixMeta *) meta;
      if (ameta->to_channels == to_channels &&
          memcmp (ameta->to_position, to_position,
              sizeof (GstAudioChannelPosition) * to_channels) == 0)
        return ameta;
    }
  }
  return NULL;
}

/**
 * gst_buffer_add_audio_downmix_meta:
 * @buffer: a #GstBuffer
 * @from_position: (array length=from_channels): the channel positions
 *   of the source
 * @from_channels: The number of channels of the source
 * @to_position: (array length=to_channels): the channel positions of
 *   the destination
 * @to_channels: The number of channels of the destination
 * @matrix: The matrix coefficients.
 *
 * Attaches GstAudioDownmixMeta metadata to @buffer with the given parameters.
 *
 * @matrix is an two-dimensional array of @to_channels times @from_channels
 * coefficients, i.e. the i-th output channels is constructed by multiplicating
 * the input channels with the coefficients in @matrix[i] and taking the sum
 * of the results.
 *
 * Returns: the #GstAudioDownmixMeta on @buffer.
 */
GstAudioDownmixMeta *
gst_buffer_add_audio_downmix_meta (GstBuffer * buffer,
    const GstAudioChannelPosition * from_position, gint from_channels,
    const GstAudioChannelPosition * to_position, gint to_channels,
    const gfloat ** matrix)
{
  GstAudioDownmixMeta *meta;
  gint i;

  g_return_val_if_fail (from_position != NULL, NULL);
  g_return_val_if_fail (from_channels > 0, NULL);
  g_return_val_if_fail (to_position != NULL, NULL);
  g_return_val_if_fail (to_channels > 0, NULL);
  g_return_val_if_fail (matrix != NULL, NULL);

  meta =
      (GstAudioDownmixMeta *) gst_buffer_add_meta (buffer,
      GST_AUDIO_DOWNMIX_META_INFO, NULL);

  meta->from_channels = from_channels;
  meta->to_channels = to_channels;

  meta->from_position =
      g_new (GstAudioChannelPosition, meta->from_channels + meta->to_channels);
  meta->to_position = meta->from_position + meta->from_channels;
  memcpy (meta->from_position, from_position,
      sizeof (GstAudioChannelPosition) * meta->from_channels);
  memcpy (meta->to_position, to_position,
      sizeof (GstAudioChannelPosition) * meta->to_channels);

  meta->matrix = g_new (gfloat *, meta->to_channels);
  meta->matrix[0] = g_new (gfloat, meta->from_channels * meta->to_channels);
  memcpy (meta->matrix[0], matrix[0], sizeof (gfloat) * meta->from_channels);
  for (i = 1; i < meta->to_channels; i++) {
    meta->matrix[i] = meta->matrix[0] + i * meta->from_channels;
    memcpy (meta->matrix[i], matrix[i], sizeof (gfloat) * meta->from_channels);
  }

  return meta;
}

GType
gst_audio_downmix_meta_api_get_type (void)
{
  static volatile GType type;
  static const gchar *tags[] =
      { GST_META_TAG_AUDIO_STR, GST_META_TAG_AUDIO_CHANNELS_STR, NULL };

  if (g_once_init_enter (&type)) {
    GType _type = gst_meta_api_type_register ("GstAudioDownmixMetaAPI", tags);
    g_once_init_leave (&type, _type);
  }
  return type;
}

const GstMetaInfo *
gst_audio_downmix_meta_get_info (void)
{
  static const GstMetaInfo *audio_downmix_meta_info = NULL;

  if (g_once_init_enter (&audio_downmix_meta_info)) {
    const GstMetaInfo *meta =
        gst_meta_register (GST_AUDIO_DOWNMIX_META_API_TYPE,
        "GstAudioDownmixMeta", sizeof (GstAudioDownmixMeta),
        gst_audio_downmix_meta_init, gst_audio_downmix_meta_free,
        gst_audio_downmix_meta_transform);
    g_once_init_leave (&audio_downmix_meta_info, meta);
  }
  return audio_downmix_meta_info;
}