2 * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg 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 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 * audio conversion routines
28 #include "audioconvert.h"
30 static const char * const channel_names[] = {
31 [0] = "FL", /* front left */
32 [1] = "FR", /* front right */
33 [2] = "FC", /* front center */
34 [3] = "LFE", /* low frequency */
35 [4] = "BL", /* back left */
36 [5] = "BR", /* back right */
37 [6] = "FLC", /* front left-of-center */
38 [7] = "FRC", /* front right-of-center */
39 [8] = "BC", /* back-center */
40 [9] = "SL", /* side left */
41 [10] = "SR", /* side right */
42 [11] = "TC", /* top center */
43 [12] = "TFL", /* top front left */
44 [13] = "TFC", /* top front center */
45 [14] = "TFR", /* top front right */
46 [15] = "TBL", /* top back left */
47 [16] = "TBC", /* top back center */
48 [17] = "TBR", /* top back right */
49 [29] = "DL", /* downmix left */
50 [30] = "DR", /* downmix right */
51 [31] = "WL", /* wide left */
52 [32] = "WR", /* wide right */
53 [33] = "SDL", /* surround direct left */
54 [34] = "SDR", /* surround direct right */
57 static const char *get_channel_name(int channel_id)
59 if (channel_id < 0 || channel_id >= FF_ARRAY_ELEMS(channel_names))
61 return channel_names[channel_id];
68 } channel_layout_map[] = {
69 { "mono", 1, AV_CH_LAYOUT_MONO },
70 { "stereo", 2, AV_CH_LAYOUT_STEREO },
71 { "2.1", 3, AV_CH_LAYOUT_2POINT1 },
72 { "3.0", 3, AV_CH_LAYOUT_SURROUND },
73 { "3.0(back)", 3, AV_CH_LAYOUT_2_1 },
74 { "4.0", 4, AV_CH_LAYOUT_4POINT0 },
75 { "quad", 4, AV_CH_LAYOUT_QUAD },
76 { "quad(side)", 4, AV_CH_LAYOUT_2_2 },
77 { "3.1", 4, AV_CH_LAYOUT_3POINT1 },
78 { "5.0", 5, AV_CH_LAYOUT_5POINT0_BACK },
79 { "5.0(side)", 5, AV_CH_LAYOUT_5POINT0 },
80 { "4.1", 5, AV_CH_LAYOUT_4POINT1 },
81 { "5.1", 6, AV_CH_LAYOUT_5POINT1_BACK },
82 { "5.1(side)", 6, AV_CH_LAYOUT_5POINT1 },
83 // { "5.1+downmix", 8, AV_CH_LAYOUT_5POINT1|AV_CH_LAYOUT_STEREO_DOWNMIX, },
84 { "6.0", 6, AV_CH_LAYOUT_6POINT0 },
85 { "6.0(front)", 6, AV_CH_LAYOUT_6POINT0_FRONT },
86 { "hexagonal", 6, AV_CH_LAYOUT_HEXAGONAL },
87 { "6.1", 7, AV_CH_LAYOUT_6POINT1 },
88 { "6.1", 7, AV_CH_LAYOUT_6POINT1_BACK },
89 { "6.1(front)", 7, AV_CH_LAYOUT_6POINT1_FRONT },
90 // { "6.1+downmix", 9, AV_CH_LAYOUT_6POINT1|AV_CH_LAYOUT_STEREO_DOWNMIX, },
91 { "7.0", 7, AV_CH_LAYOUT_7POINT0 },
92 { "7.0(front)", 7, AV_CH_LAYOUT_7POINT0_FRONT },
93 { "7.1", 8, AV_CH_LAYOUT_7POINT1 },
94 { "7.1(wide)", 8, AV_CH_LAYOUT_7POINT1_WIDE },
95 // { "7.1+downmix", 10, AV_CH_LAYOUT_7POINT1|AV_CH_LAYOUT_STEREO_DOWNMIX, },
96 { "octagonal", 8, AV_CH_LAYOUT_OCTAGONAL },
97 { "downmix", 2, AV_CH_LAYOUT_STEREO_DOWNMIX, },
100 static uint64_t get_channel_layout_single(const char *name, int name_len)
106 for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++) {
107 if (strlen(channel_layout_map[i].name) == name_len &&
108 !memcmp(channel_layout_map[i].name, name, name_len))
109 return channel_layout_map[i].layout;
111 for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++)
112 if (channel_names[i] &&
113 strlen(channel_names[i]) == name_len &&
114 !memcmp(channel_names[i], name, name_len))
115 return (int64_t)1 << i;
116 i = strtol(name, &end, 10);
117 if (end - name == name_len ||
118 (end + 1 - name == name_len && *end == 'c'))
119 return av_get_default_channel_layout(i);
120 layout = strtoll(name, &end, 0);
121 if (end - name == name_len)
122 return FFMAX(layout, 0);
126 uint64_t av_get_channel_layout(const char *name)
129 const char *name_end = name + strlen(name);
130 int64_t layout = 0, layout_single;
132 for (n = name; n < name_end; n = e + 1) {
133 for (e = n; e < name_end && *e != '+' && *e != '|'; e++);
134 layout_single = get_channel_layout_single(n, e - n);
137 layout |= layout_single;
142 void av_get_channel_layout_string(char *buf, int buf_size,
143 int nb_channels, uint64_t channel_layout)
147 if (nb_channels <= 0)
148 nb_channels = av_get_channel_layout_nb_channels(channel_layout);
150 for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++)
151 if (nb_channels == channel_layout_map[i].nb_channels &&
152 channel_layout == channel_layout_map[i].layout) {
153 av_strlcpy(buf, channel_layout_map[i].name, buf_size);
157 snprintf(buf, buf_size, "%d channels", nb_channels);
158 if (channel_layout) {
160 av_strlcat(buf, " (", buf_size);
161 for (i = 0, ch = 0; i < 64; i++) {
162 if ((channel_layout & (UINT64_C(1) << i))) {
163 const char *name = get_channel_name(i);
166 av_strlcat(buf, "+", buf_size);
167 av_strlcat(buf, name, buf_size);
172 av_strlcat(buf, ")", buf_size);
176 int av_get_channel_layout_nb_channels(uint64_t channel_layout)
179 uint64_t x = channel_layout;
180 for (count = 0; x; count++)
181 x &= x-1; // unset lowest set bit
185 int64_t av_get_default_channel_layout(int nb_channels) {
187 for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++)
188 if (nb_channels == channel_layout_map[i].nb_channels)
189 return channel_layout_map[i].layout;