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
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
|
/*
* This file is part of mpv.
*
* mpv is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* mpv 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include "common/common.h"
#include "common/msg.h"
#include "chmap_sel.h"
static const struct mp_chmap speaker_replacements[][2] = {
// 5.1 <-> 5.1 (side)
{ MP_CHMAP2(SL, SR), MP_CHMAP2(BL, BR) },
// 7.1 <-> 7.1 (rear ext)
{ MP_CHMAP2(SL, SR), MP_CHMAP2(SDL, SDR) },
};
// Try to replace speakers from the left of the list with the ones on the
// right, or the other way around.
static bool replace_speakers(struct mp_chmap *map, struct mp_chmap list[2])
{
assert(list[0].num == list[1].num);
if (!mp_chmap_is_valid(map))
return false;
for (int dir = 0; dir < 2; dir++) {
int from = dir ? 0 : 1;
int to = dir ? 1 : 0;
bool replaced = false;
struct mp_chmap t = *map;
for (int n = 0; n < t.num; n++) {
for (int i = 0; i < list[0].num; i++) {
if (t.speaker[n] == list[from].speaker[i]) {
t.speaker[n] = list[to].speaker[i];
replaced = true;
break;
}
}
}
if (replaced && mp_chmap_is_valid(&t)) {
*map = t;
return true;
}
}
return false;
}
// These go strictly from the first to the second entry and always use the
// full layout (possibly reordered and/or padding channels added).
static const struct mp_chmap preferred_remix[][2] = {
// mono can be perfectly played as stereo
{ MP_CHMAP_INIT_MONO, MP_CHMAP_INIT_STEREO },
};
// Conversion from src to dst is explicitly encouraged and should be preferred
// over "mathematical" upmixes or downmixes (which minimize lost channels).
static bool test_preferred_remix(const struct mp_chmap *src,
const struct mp_chmap *dst)
{
struct mp_chmap src_p = *src, dst_p = *dst;
mp_chmap_remove_na(&src_p);
mp_chmap_remove_na(&dst_p);
for (int n = 0; n < MP_ARRAY_SIZE(preferred_remix); n++) {
if (mp_chmap_equals_reordered(&src_p, &preferred_remix[n][0]) &&
mp_chmap_equals_reordered(&dst_p, &preferred_remix[n][1]))
return true;
}
return false;
}
// Allow all channel layouts that can be expressed with mp_chmap.
// (By default, all layouts are rejected.)
void mp_chmap_sel_add_any(struct mp_chmap_sel *s)
{
s->allow_any = true;
}
// Allow all waveext formats, and force waveext channel order.
void mp_chmap_sel_add_waveext(struct mp_chmap_sel *s)
{
s->allow_waveext = true;
}
// Add a channel map that should be allowed.
void mp_chmap_sel_add_map(struct mp_chmap_sel *s, const struct mp_chmap *map)
{
if (!mp_chmap_is_valid(map))
return;
if (!s->chmaps)
s->chmaps = s->chmaps_storage;
if (s->num_chmaps == MP_ARRAY_SIZE(s->chmaps_storage)) {
if (!s->tmp)
return;
s->chmaps = talloc_memdup(s->tmp, s->chmaps, sizeof(s->chmaps_storage));
}
if (s->chmaps != s->chmaps_storage)
MP_TARRAY_GROW(s->tmp, s->chmaps, s->num_chmaps);
s->chmaps[s->num_chmaps++] = *map;
}
// Allow all waveext formats in default order.
void mp_chmap_sel_add_waveext_def(struct mp_chmap_sel *s)
{
for (int n = 1; n <= MP_NUM_CHANNELS; n++) {
struct mp_chmap map;
mp_chmap_from_channels(&map, n);
mp_chmap_sel_add_map(s, &map);
}
}
// Whitelist a speaker (MP_SPEAKER_ID_...). All layouts that contain whitelisted
// speakers are allowed.
void mp_chmap_sel_add_speaker(struct mp_chmap_sel *s, int id)
{
assert(id >= 0 && id < MP_SPEAKER_ID_COUNT);
s->speakers[id] = true;
}
static bool test_speakers(const struct mp_chmap_sel *s, struct mp_chmap *map)
{
for (int n = 0; n < map->num; n++) {
if (!s->speakers[map->speaker[n]])
return false;
}
return true;
}
static bool test_maps(const struct mp_chmap_sel *s, struct mp_chmap *map)
{
for (int n = 0; n < s->num_chmaps; n++) {
if (mp_chmap_equals_reordered(&s->chmaps[n], map)) {
*map = s->chmaps[n];
return true;
}
}
return false;
}
static bool test_waveext(const struct mp_chmap_sel *s, struct mp_chmap *map)
{
if (s->allow_waveext) {
struct mp_chmap t = *map;
mp_chmap_reorder_to_waveext(&t);
if (mp_chmap_is_waveext(&t)) {
*map = t;
return true;
}
}
return false;
}
static bool test_layout(const struct mp_chmap_sel *s, struct mp_chmap *map)
{
if (!mp_chmap_is_valid(map))
return false;
return s->allow_any || test_waveext(s, map) || test_speakers(s, map) ||
test_maps(s, map);
}
// Determine which channel map to use given a source channel map, and various
// parameters restricting possible choices. If the map doesn't match, select
// a fallback and set it.
// If no matching layout is found, a reordered layout may be returned.
// If that is not possible, a fallback for up/downmixing may be returned.
// If no choice is possible, set *map to empty.
bool mp_chmap_sel_adjust(const struct mp_chmap_sel *s, struct mp_chmap *map)
{
if (test_layout(s, map))
return true;
if (mp_chmap_is_unknown(map)) {
struct mp_chmap t = {0};
if (mp_chmap_sel_get_def(s, &t, map->num) && test_layout(s, &t)) {
*map = t;
return true;
}
}
if (mp_chmap_sel_fallback(s, map))
return true;
for (int i = 0; i < MP_ARRAY_SIZE(speaker_replacements); i++) {
struct mp_chmap t = *map;
struct mp_chmap *r = (struct mp_chmap *)speaker_replacements[i];
if (replace_speakers(&t, r) && test_layout(s, &t)) {
*map = t;
return true;
}
}
// Fallback to mono/stereo as last resort
*map = (struct mp_chmap) MP_CHMAP_INIT_STEREO;
if (test_layout(s, map))
return true;
*map = (struct mp_chmap) MP_CHMAP_INIT_MONO;
if (test_layout(s, map))
return true;
*map = (struct mp_chmap) {0};
return false;
}
// Like mp_chmap_diffn(), but find the minimum difference with all possible
// speaker replacements considered.
static int mp_chmap_diffn_r(const struct mp_chmap *a, const struct mp_chmap *b)
{
int mindiff = INT_MAX;
for (int i = -1; i < (int)MP_ARRAY_SIZE(speaker_replacements); i++) {
struct mp_chmap ar = *a;
if (i >= 0) {
struct mp_chmap *r = (struct mp_chmap *)speaker_replacements[i];
if (!replace_speakers(&ar, r))
continue;
}
int d = mp_chmap_diffn(&ar, b);
if (d < mindiff)
mindiff = d;
}
// Special-case: we consider stereo a replacement for mono. (This is not
// true in the other direction. Also, fl-fr is generally not a replacement
// for fc. Thus it's not part of the speaker replacement list.)
struct mp_chmap mono = MP_CHMAP_INIT_MONO;
struct mp_chmap stereo = MP_CHMAP_INIT_STEREO;
if (mp_chmap_equals(&mono, b) && mp_chmap_equals(&stereo, a))
mindiff = 0;
return mindiff;
}
// Decide whether we should prefer old or new for the requested layout.
// Return true if new should be used, false if old should be used.
// If old is empty, always return new (initial case).
static bool mp_chmap_is_better(struct mp_chmap *req, struct mp_chmap *old,
struct mp_chmap *new)
{
// Initial case
if (!old->num)
return true;
// Exact pick - this also ensures that the best layout is chosen if the
// layouts are the same, but with different order of channels.
if (mp_chmap_equals(req, old))
return false;
if (mp_chmap_equals(req, new))
return true;
// If there's no exact match, strictly do a preferred conversion.
bool old_pref = test_preferred_remix(req, old);
bool new_pref = test_preferred_remix(req, new);
if (old_pref && !new_pref)
return false;
if (!old_pref && new_pref)
return true;
int old_lost_r = mp_chmap_diffn_r(req, old); // num. channels only in req
int new_lost_r = mp_chmap_diffn_r(req, new);
// Imperfect upmix (no real superset) - minimize lost channels
if (new_lost_r != old_lost_r)
return new_lost_r < old_lost_r;
struct mp_chmap old_p = *old, new_p = *new;
mp_chmap_remove_na(&old_p);
mp_chmap_remove_na(&new_p);
// If the situation is equal with replaced speakers, but the replacement is
// perfect for only one of them, let the better one win. This prefers
// inexact equivalents over exact supersets.
bool perfect_r_new = !new_lost_r && new_p.num <= old_p.num;
bool perfect_r_old = !old_lost_r && old_p.num <= new_p.num;
if (perfect_r_new != perfect_r_old)
return perfect_r_new;
int old_lost = mp_chmap_diffn(req, old);
int new_lost = mp_chmap_diffn(req, new);
// If the situation is equal with replaced speakers, pick the better one,
// even if it means an upmix.
if (new_lost != old_lost)
return new_lost < old_lost;
// Some kind of upmix. If it's perfect, prefer the smaller one. Even if not,
// both have equal loss, so also prefer the smaller one.
// Drop padding channels (NA) for the sake of this check, as the number of
// padding channels isn't really meaningful.
if (new_p.num != old_p.num)
return new_p.num < old_p.num;
// Again, with physical channels (minimizes number of NA channels).
return new->num < old->num;
}
// Determine which channel map to fallback to given a source channel map.
bool mp_chmap_sel_fallback(const struct mp_chmap_sel *s, struct mp_chmap *map)
{
struct mp_chmap best = {0};
for (int n = 0; n < s->num_chmaps; n++) {
struct mp_chmap e = s->chmaps[n];
if (mp_chmap_is_unknown(&e))
continue;
if (mp_chmap_is_better(map, &best, &e))
best = e;
}
if (best.num) {
*map = best;
return true;
}
return false;
}
// Set map to a default layout with num channels. Used for audio APIs that
// return a channel count as part of format negotiation, but give no
// information about the channel layout.
// If the channel count is correct, do nothing and leave *map untouched.
bool mp_chmap_sel_get_def(const struct mp_chmap_sel *s, struct mp_chmap *map,
int num)
{
if (map->num != num) {
*map = (struct mp_chmap) {0};
// Set of speakers or waveext might allow it.
struct mp_chmap t;
mp_chmap_from_channels(&t, num);
mp_chmap_reorder_to_waveext(&t);
if (test_layout(s, &t)) {
*map = t;
} else {
for (int n = 0; n < s->num_chmaps; n++) {
if (s->chmaps[n].num == num) {
*map = s->chmaps[n];
break;
}
}
}
}
return map->num > 0;
}
// Print the set of allowed channel layouts.
void mp_chmal_sel_log(const struct mp_chmap_sel *s, struct mp_log *log, int lev)
{
if (!mp_msg_test(log, lev))
return;
for (int i = 0; i < s->num_chmaps; i++)
mp_msg(log, lev, " - %s\n", mp_chmap_to_str(&s->chmaps[i]));
for (int i = 0; i < MP_SPEAKER_ID_COUNT; i++) {
if (!s->speakers[i])
continue;
struct mp_chmap l = {.num = 1, .speaker = { i }};
mp_msg(log, lev, " - #%s\n",
i == MP_SPEAKER_ID_FC ? "fc" : mp_chmap_to_str_hr(&l));
}
if (s->allow_waveext)
mp_msg(log, lev, " - waveext\n");
if (s->allow_any)
mp_msg(log, lev, " - anything\n");
}
|