1 /*
2 * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
3 *
4 * This file is part of FFmpeg.
5 *
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.
10 *
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.
15 *
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
19 */
20
21 /**
22 * @file
23 * audio channel layout utility functions
24 */
25
26 #include <stdint.h>
27
28 #include "avstring.h"
29 #include "avutil.h"
30 #include "channel_layout.h"
31 #include "bprint.h"
32 #include "common.h"
33
34 struct channel_name {
35 const char *name;
36 const char *description;
37 };
38
39 static const struct channel_name channel_names[] = {
40 [0] = { "FL", "front left" },
41 [1] = { "FR", "front right" },
42 [2] = { "FC", "front center" },
43 [3] = { "LFE", "low frequency" },
44 [4] = { "BL", "back left" },
45 [5] = { "BR", "back right" },
46 [6] = { "FLC", "front left-of-center" },
47 [7] = { "FRC", "front right-of-center" },
48 [8] = { "BC", "back center" },
49 [9] = { "SL", "side left" },
50 [10] = { "SR", "side right" },
51 [11] = { "TC", "top center" },
52 [12] = { "TFL", "top front left" },
53 [13] = { "TFC", "top front center" },
54 [14] = { "TFR", "top front right" },
55 [15] = { "TBL", "top back left" },
56 [16] = { "TBC", "top back center" },
57 [17] = { "TBR", "top back right" },
58 [29] = { "DL", "downmix left" },
59 [30] = { "DR", "downmix right" },
60 [31] = { "WL", "wide left" },
61 [32] = { "WR", "wide right" },
62 [33] = { "SDL", "surround direct left" },
63 [34] = { "SDR", "surround direct right" },
64 [35] = { "LFE2", "low frequency 2" },
65 [36] = { "TSL", "top side left" },
66 [37] = { "TSR", "top side right" },
67 [38] = { "BFC", "bottom front center" },
68 [39] = { "BFL", "bottom front left" },
69 [40] = { "BFR", "bottom front right" },
70 };
71
get_channel_name(int channel_id)72 static const char *get_channel_name(int channel_id)
73 {
74 if (channel_id < 0 || channel_id >= FF_ARRAY_ELEMS(channel_names))
75 return NULL;
76 return channel_names[channel_id].name;
77 }
78
79 static const struct {
80 const char *name;
81 int nb_channels;
82 uint64_t layout;
83 } channel_layout_map[] = {
84 { "mono", 1, AV_CH_LAYOUT_MONO },
85 { "stereo", 2, AV_CH_LAYOUT_STEREO },
86 { "2.1", 3, AV_CH_LAYOUT_2POINT1 },
87 { "3.0", 3, AV_CH_LAYOUT_SURROUND },
88 { "3.0(back)", 3, AV_CH_LAYOUT_2_1 },
89 { "4.0", 4, AV_CH_LAYOUT_4POINT0 },
90 { "quad", 4, AV_CH_LAYOUT_QUAD },
91 { "quad(side)", 4, AV_CH_LAYOUT_2_2 },
92 { "3.1", 4, AV_CH_LAYOUT_3POINT1 },
93 { "5.0", 5, AV_CH_LAYOUT_5POINT0_BACK },
94 { "5.0(side)", 5, AV_CH_LAYOUT_5POINT0 },
95 { "4.1", 5, AV_CH_LAYOUT_4POINT1 },
96 { "5.1", 6, AV_CH_LAYOUT_5POINT1_BACK },
97 { "5.1(side)", 6, AV_CH_LAYOUT_5POINT1 },
98 { "6.0", 6, AV_CH_LAYOUT_6POINT0 },
99 { "6.0(front)", 6, AV_CH_LAYOUT_6POINT0_FRONT },
100 { "hexagonal", 6, AV_CH_LAYOUT_HEXAGONAL },
101 { "6.1", 7, AV_CH_LAYOUT_6POINT1 },
102 { "6.1(back)", 7, AV_CH_LAYOUT_6POINT1_BACK },
103 { "6.1(front)", 7, AV_CH_LAYOUT_6POINT1_FRONT },
104 { "7.0", 7, AV_CH_LAYOUT_7POINT0 },
105 { "7.0(front)", 7, AV_CH_LAYOUT_7POINT0_FRONT },
106 { "7.1", 8, AV_CH_LAYOUT_7POINT1 },
107 { "7.1(wide)", 8, AV_CH_LAYOUT_7POINT1_WIDE_BACK },
108 { "7.1(wide-side)", 8, AV_CH_LAYOUT_7POINT1_WIDE },
109 { "octagonal", 8, AV_CH_LAYOUT_OCTAGONAL },
110 { "hexadecagonal", 16, AV_CH_LAYOUT_HEXADECAGONAL },
111 { "downmix", 2, AV_CH_LAYOUT_STEREO_DOWNMIX, },
112 { "22.2", 24, AV_CH_LAYOUT_22POINT2, },
113 };
114
get_channel_layout_single(const char * name,int name_len)115 static uint64_t get_channel_layout_single(const char *name, int name_len)
116 {
117 int i;
118 char *end;
119 int64_t layout;
120
121 for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++) {
122 if (strlen(channel_layout_map[i].name) == name_len &&
123 !memcmp(channel_layout_map[i].name, name, name_len))
124 return channel_layout_map[i].layout;
125 }
126 for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++)
127 if (channel_names[i].name &&
128 strlen(channel_names[i].name) == name_len &&
129 !memcmp(channel_names[i].name, name, name_len))
130 return (int64_t)1 << i;
131
132 errno = 0;
133 i = strtol(name, &end, 10);
134
135 if (!errno && (end + 1 - name == name_len && *end == 'c'))
136 return av_get_default_channel_layout(i);
137
138 errno = 0;
139 layout = strtoll(name, &end, 0);
140 if (!errno && end - name == name_len)
141 return FFMAX(layout, 0);
142 return 0;
143 }
144
av_get_channel_layout(const char * name)145 uint64_t av_get_channel_layout(const char *name)
146 {
147 const char *n, *e;
148 const char *name_end = name + strlen(name);
149 int64_t layout = 0, layout_single;
150
151 for (n = name; n < name_end; n = e + 1) {
152 for (e = n; e < name_end && *e != '+' && *e != '|'; e++);
153 layout_single = get_channel_layout_single(n, e - n);
154 if (!layout_single)
155 return 0;
156 layout |= layout_single;
157 }
158 return layout;
159 }
160
av_get_extended_channel_layout(const char * name,uint64_t * channel_layout,int * nb_channels)161 int av_get_extended_channel_layout(const char *name, uint64_t* channel_layout, int* nb_channels)
162 {
163 int nb = 0;
164 char *end;
165 uint64_t layout = av_get_channel_layout(name);
166
167 if (layout) {
168 *channel_layout = layout;
169 *nb_channels = av_get_channel_layout_nb_channels(layout);
170 return 0;
171 }
172
173 nb = strtol(name, &end, 10);
174 if (!errno && *end == 'C' && *(end + 1) == '\0' && nb > 0 && nb < 64) {
175 *channel_layout = 0;
176 *nb_channels = nb;
177 return 0;
178 }
179
180 return AVERROR(EINVAL);
181 }
182
av_bprint_channel_layout(struct AVBPrint * bp,int nb_channels,uint64_t channel_layout)183 void av_bprint_channel_layout(struct AVBPrint *bp,
184 int nb_channels, uint64_t channel_layout)
185 {
186 int i;
187
188 if (nb_channels <= 0)
189 nb_channels = av_get_channel_layout_nb_channels(channel_layout);
190
191 for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++)
192 if (nb_channels == channel_layout_map[i].nb_channels &&
193 channel_layout == channel_layout_map[i].layout) {
194 av_bprintf(bp, "%s", channel_layout_map[i].name);
195 return;
196 }
197
198 av_bprintf(bp, "%d channels", nb_channels);
199 if (channel_layout) {
200 int i, ch;
201 av_bprintf(bp, " (");
202 for (i = 0, ch = 0; i < 64; i++) {
203 if ((channel_layout & (UINT64_C(1) << i))) {
204 const char *name = get_channel_name(i);
205 if (name) {
206 if (ch > 0)
207 av_bprintf(bp, "+");
208 av_bprintf(bp, "%s", name);
209 }
210 ch++;
211 }
212 }
213 av_bprintf(bp, ")");
214 }
215 }
216
av_get_channel_layout_string(char * buf,int buf_size,int nb_channels,uint64_t channel_layout)217 void av_get_channel_layout_string(char *buf, int buf_size,
218 int nb_channels, uint64_t channel_layout)
219 {
220 AVBPrint bp;
221
222 av_bprint_init_for_buffer(&bp, buf, buf_size);
223 av_bprint_channel_layout(&bp, nb_channels, channel_layout);
224 }
225
av_get_channel_layout_nb_channels(uint64_t channel_layout)226 int av_get_channel_layout_nb_channels(uint64_t channel_layout)
227 {
228 return av_popcount64(channel_layout);
229 }
230
av_get_default_channel_layout(int nb_channels)231 int64_t av_get_default_channel_layout(int nb_channels) {
232 int i;
233 for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++)
234 if (nb_channels == channel_layout_map[i].nb_channels)
235 return channel_layout_map[i].layout;
236 return 0;
237 }
238
av_get_channel_layout_channel_index(uint64_t channel_layout,uint64_t channel)239 int av_get_channel_layout_channel_index(uint64_t channel_layout,
240 uint64_t channel)
241 {
242 if (!(channel_layout & channel) ||
243 av_get_channel_layout_nb_channels(channel) != 1)
244 return AVERROR(EINVAL);
245 channel_layout &= channel - 1;
246 return av_get_channel_layout_nb_channels(channel_layout);
247 }
248
av_get_channel_name(uint64_t channel)249 const char *av_get_channel_name(uint64_t channel)
250 {
251 int i;
252 if (av_get_channel_layout_nb_channels(channel) != 1)
253 return NULL;
254 for (i = 0; i < 64; i++)
255 if ((1ULL<<i) & channel)
256 return get_channel_name(i);
257 return NULL;
258 }
259
av_get_channel_description(uint64_t channel)260 const char *av_get_channel_description(uint64_t channel)
261 {
262 int i;
263 if (av_get_channel_layout_nb_channels(channel) != 1)
264 return NULL;
265 for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++)
266 if ((1ULL<<i) & channel)
267 return channel_names[i].description;
268 return NULL;
269 }
270
av_channel_layout_extract_channel(uint64_t channel_layout,int index)271 uint64_t av_channel_layout_extract_channel(uint64_t channel_layout, int index)
272 {
273 int i;
274
275 if (av_get_channel_layout_nb_channels(channel_layout) <= index)
276 return 0;
277
278 for (i = 0; i < 64; i++) {
279 if ((1ULL << i) & channel_layout && !index--)
280 return 1ULL << i;
281 }
282 return 0;
283 }
284
av_get_standard_channel_layout(unsigned index,uint64_t * layout,const char ** name)285 int av_get_standard_channel_layout(unsigned index, uint64_t *layout,
286 const char **name)
287 {
288 if (index >= FF_ARRAY_ELEMS(channel_layout_map))
289 return AVERROR_EOF;
290 if (layout) *layout = channel_layout_map[index].layout;
291 if (name) *name = channel_layout_map[index].name;
292 return 0;
293 }
294