| 1 | /* |
| 2 | * Copyright (c) 2012 Google, Inc. |
| 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 mapping filter |
| 24 | */ |
| 25 | |
| 26 | #include <ctype.h> |
| 27 | |
| 28 | #include "libavutil/avstring.h" |
| 29 | #include "libavutil/channel_layout.h" |
| 30 | #include "libavutil/common.h" |
| 31 | #include "libavutil/mathematics.h" |
| 32 | #include "libavutil/opt.h" |
| 33 | #include "libavutil/samplefmt.h" |
| 34 | |
| 35 | #include "audio.h" |
| 36 | #include "avfilter.h" |
| 37 | #include "formats.h" |
| 38 | #include "internal.h" |
| 39 | |
| 40 | struct ChannelMap { |
| 41 | uint64_t in_channel; |
| 42 | uint64_t out_channel; |
| 43 | int in_channel_idx; |
| 44 | int out_channel_idx; |
| 45 | }; |
| 46 | |
| 47 | enum MappingMode { |
| 48 | MAP_NONE, |
| 49 | MAP_ONE_INT, |
| 50 | MAP_ONE_STR, |
| 51 | MAP_PAIR_INT_INT, |
| 52 | MAP_PAIR_INT_STR, |
| 53 | MAP_PAIR_STR_INT, |
| 54 | MAP_PAIR_STR_STR |
| 55 | }; |
| 56 | |
| 57 | #define MAX_CH 64 |
| 58 | typedef struct ChannelMapContext { |
| 59 | const AVClass *class; |
| 60 | AVFilterChannelLayouts *channel_layouts; |
| 61 | char *mapping_str; |
| 62 | char *channel_layout_str; |
| 63 | uint64_t output_layout; |
| 64 | struct ChannelMap map[MAX_CH]; |
| 65 | int nch; |
| 66 | enum MappingMode mode; |
| 67 | } ChannelMapContext; |
| 68 | |
| 69 | #define OFFSET(x) offsetof(ChannelMapContext, x) |
| 70 | #define A AV_OPT_FLAG_AUDIO_PARAM |
| 71 | #define F AV_OPT_FLAG_FILTERING_PARAM |
| 72 | static const AVOption channelmap_options[] = { |
| 73 | { "map", "A comma-separated list of input channel numbers in output order.", |
| 74 | OFFSET(mapping_str), AV_OPT_TYPE_STRING, .flags = A|F }, |
| 75 | { "channel_layout", "Output channel layout.", |
| 76 | OFFSET(channel_layout_str), AV_OPT_TYPE_STRING, .flags = A|F }, |
| 77 | { NULL } |
| 78 | }; |
| 79 | |
| 80 | AVFILTER_DEFINE_CLASS(channelmap); |
| 81 | |
| 82 | static char* split(char *message, char delim) { |
| 83 | char *next = strchr(message, delim); |
| 84 | if (next) |
| 85 | *next++ = '\0'; |
| 86 | return next; |
| 87 | } |
| 88 | |
| 89 | static int get_channel_idx(char **map, int *ch, char delim, int max_ch) |
| 90 | { |
| 91 | char *next = split(*map, delim); |
| 92 | int len; |
| 93 | int n = 0; |
| 94 | if (!next && delim == '-') |
| 95 | return AVERROR(EINVAL); |
| 96 | len = strlen(*map); |
| 97 | sscanf(*map, "%d%n", ch, &n); |
| 98 | if (n != len) |
| 99 | return AVERROR(EINVAL); |
| 100 | if (*ch < 0 || *ch > max_ch) |
| 101 | return AVERROR(EINVAL); |
| 102 | *map = next; |
| 103 | return 0; |
| 104 | } |
| 105 | |
| 106 | static int get_channel(char **map, uint64_t *ch, char delim) |
| 107 | { |
| 108 | char *next = split(*map, delim); |
| 109 | if (!next && delim == '-') |
| 110 | return AVERROR(EINVAL); |
| 111 | *ch = av_get_channel_layout(*map); |
| 112 | if (av_get_channel_layout_nb_channels(*ch) != 1) |
| 113 | return AVERROR(EINVAL); |
| 114 | *map = next; |
| 115 | return 0; |
| 116 | } |
| 117 | |
| 118 | static av_cold int channelmap_init(AVFilterContext *ctx) |
| 119 | { |
| 120 | ChannelMapContext *s = ctx->priv; |
| 121 | char *mapping, separator = '|'; |
| 122 | int map_entries = 0; |
| 123 | char buf[256]; |
| 124 | enum MappingMode mode; |
| 125 | uint64_t out_ch_mask = 0; |
| 126 | int i; |
| 127 | |
| 128 | mapping = s->mapping_str; |
| 129 | |
| 130 | if (!mapping) { |
| 131 | mode = MAP_NONE; |
| 132 | } else { |
| 133 | char *dash = strchr(mapping, '-'); |
| 134 | if (!dash) { // short mapping |
| 135 | if (av_isdigit(*mapping)) |
| 136 | mode = MAP_ONE_INT; |
| 137 | else |
| 138 | mode = MAP_ONE_STR; |
| 139 | } else if (av_isdigit(*mapping)) { |
| 140 | if (av_isdigit(*(dash+1))) |
| 141 | mode = MAP_PAIR_INT_INT; |
| 142 | else |
| 143 | mode = MAP_PAIR_INT_STR; |
| 144 | } else { |
| 145 | if (av_isdigit(*(dash+1))) |
| 146 | mode = MAP_PAIR_STR_INT; |
| 147 | else |
| 148 | mode = MAP_PAIR_STR_STR; |
| 149 | } |
| 150 | #if FF_API_OLD_FILTER_OPTS |
| 151 | if (strchr(mapping, ',')) { |
| 152 | av_log(ctx, AV_LOG_WARNING, "This syntax is deprecated, use " |
| 153 | "'|' to separate the mappings.\n"); |
| 154 | separator = ','; |
| 155 | } |
| 156 | #endif |
| 157 | } |
| 158 | |
| 159 | if (mode != MAP_NONE) { |
| 160 | char *sep = mapping; |
| 161 | map_entries = 1; |
| 162 | while ((sep = strchr(sep, separator))) { |
| 163 | if (*++sep) // Allow trailing comma |
| 164 | map_entries++; |
| 165 | } |
| 166 | } |
| 167 | |
| 168 | if (map_entries > MAX_CH) { |
| 169 | av_log(ctx, AV_LOG_ERROR, "Too many channels mapped: '%d'.\n", map_entries); |
| 170 | return AVERROR(EINVAL); |
| 171 | } |
| 172 | |
| 173 | for (i = 0; i < map_entries; i++) { |
| 174 | int in_ch_idx = -1, out_ch_idx = -1; |
| 175 | uint64_t in_ch = 0, out_ch = 0; |
| 176 | static const char err[] = "Failed to parse channel map\n"; |
| 177 | switch (mode) { |
| 178 | case MAP_ONE_INT: |
| 179 | if (get_channel_idx(&mapping, &in_ch_idx, separator, MAX_CH) < 0) { |
| 180 | av_log(ctx, AV_LOG_ERROR, err); |
| 181 | return AVERROR(EINVAL); |
| 182 | } |
| 183 | s->map[i].in_channel_idx = in_ch_idx; |
| 184 | s->map[i].out_channel_idx = i; |
| 185 | break; |
| 186 | case MAP_ONE_STR: |
| 187 | if (get_channel(&mapping, &in_ch, separator) < 0) { |
| 188 | av_log(ctx, AV_LOG_ERROR, err); |
| 189 | return AVERROR(EINVAL); |
| 190 | } |
| 191 | s->map[i].in_channel = in_ch; |
| 192 | s->map[i].out_channel_idx = i; |
| 193 | break; |
| 194 | case MAP_PAIR_INT_INT: |
| 195 | if (get_channel_idx(&mapping, &in_ch_idx, '-', MAX_CH) < 0 || |
| 196 | get_channel_idx(&mapping, &out_ch_idx, separator, MAX_CH) < 0) { |
| 197 | av_log(ctx, AV_LOG_ERROR, err); |
| 198 | return AVERROR(EINVAL); |
| 199 | } |
| 200 | s->map[i].in_channel_idx = in_ch_idx; |
| 201 | s->map[i].out_channel_idx = out_ch_idx; |
| 202 | break; |
| 203 | case MAP_PAIR_INT_STR: |
| 204 | if (get_channel_idx(&mapping, &in_ch_idx, '-', MAX_CH) < 0 || |
| 205 | get_channel(&mapping, &out_ch, separator) < 0 || |
| 206 | out_ch & out_ch_mask) { |
| 207 | av_log(ctx, AV_LOG_ERROR, err); |
| 208 | return AVERROR(EINVAL); |
| 209 | } |
| 210 | s->map[i].in_channel_idx = in_ch_idx; |
| 211 | s->map[i].out_channel = out_ch; |
| 212 | out_ch_mask |= out_ch; |
| 213 | break; |
| 214 | case MAP_PAIR_STR_INT: |
| 215 | if (get_channel(&mapping, &in_ch, '-') < 0 || |
| 216 | get_channel_idx(&mapping, &out_ch_idx, separator, MAX_CH) < 0) { |
| 217 | av_log(ctx, AV_LOG_ERROR, err); |
| 218 | return AVERROR(EINVAL); |
| 219 | } |
| 220 | s->map[i].in_channel = in_ch; |
| 221 | s->map[i].out_channel_idx = out_ch_idx; |
| 222 | break; |
| 223 | case MAP_PAIR_STR_STR: |
| 224 | if (get_channel(&mapping, &in_ch, '-') < 0 || |
| 225 | get_channel(&mapping, &out_ch, separator) < 0 || |
| 226 | out_ch & out_ch_mask) { |
| 227 | av_log(ctx, AV_LOG_ERROR, err); |
| 228 | return AVERROR(EINVAL); |
| 229 | } |
| 230 | s->map[i].in_channel = in_ch; |
| 231 | s->map[i].out_channel = out_ch; |
| 232 | out_ch_mask |= out_ch; |
| 233 | break; |
| 234 | } |
| 235 | } |
| 236 | s->mode = mode; |
| 237 | s->nch = map_entries; |
| 238 | s->output_layout = out_ch_mask ? out_ch_mask : |
| 239 | av_get_default_channel_layout(map_entries); |
| 240 | |
| 241 | if (s->channel_layout_str) { |
| 242 | uint64_t fmt; |
| 243 | if ((fmt = av_get_channel_layout(s->channel_layout_str)) == 0) { |
| 244 | av_log(ctx, AV_LOG_ERROR, "Error parsing channel layout: '%s'.\n", |
| 245 | s->channel_layout_str); |
| 246 | return AVERROR(EINVAL); |
| 247 | } |
| 248 | if (mode == MAP_NONE) { |
| 249 | int i; |
| 250 | s->nch = av_get_channel_layout_nb_channels(fmt); |
| 251 | for (i = 0; i < s->nch; i++) { |
| 252 | s->map[i].in_channel_idx = i; |
| 253 | s->map[i].out_channel_idx = i; |
| 254 | } |
| 255 | } else if (out_ch_mask && out_ch_mask != fmt) { |
| 256 | av_get_channel_layout_string(buf, sizeof(buf), 0, out_ch_mask); |
| 257 | av_log(ctx, AV_LOG_ERROR, |
| 258 | "Output channel layout '%s' does not match the list of channel mapped: '%s'.\n", |
| 259 | s->channel_layout_str, buf); |
| 260 | return AVERROR(EINVAL); |
| 261 | } else if (s->nch != av_get_channel_layout_nb_channels(fmt)) { |
| 262 | av_log(ctx, AV_LOG_ERROR, |
| 263 | "Output channel layout %s does not match the number of channels mapped %d.\n", |
| 264 | s->channel_layout_str, s->nch); |
| 265 | return AVERROR(EINVAL); |
| 266 | } |
| 267 | s->output_layout = fmt; |
| 268 | } |
| 269 | if (!s->output_layout) { |
| 270 | av_log(ctx, AV_LOG_ERROR, "Output channel layout is not set and " |
| 271 | "cannot be guessed from the maps.\n"); |
| 272 | return AVERROR(EINVAL); |
| 273 | } |
| 274 | |
| 275 | ff_add_channel_layout(&s->channel_layouts, s->output_layout); |
| 276 | |
| 277 | if (mode == MAP_PAIR_INT_STR || mode == MAP_PAIR_STR_STR) { |
| 278 | for (i = 0; i < s->nch; i++) { |
| 279 | s->map[i].out_channel_idx = av_get_channel_layout_channel_index( |
| 280 | s->output_layout, s->map[i].out_channel); |
| 281 | } |
| 282 | } |
| 283 | |
| 284 | return 0; |
| 285 | } |
| 286 | |
| 287 | static int channelmap_query_formats(AVFilterContext *ctx) |
| 288 | { |
| 289 | ChannelMapContext *s = ctx->priv; |
| 290 | |
| 291 | ff_set_common_formats(ctx, ff_planar_sample_fmts()); |
| 292 | ff_set_common_samplerates(ctx, ff_all_samplerates()); |
| 293 | ff_channel_layouts_ref(ff_all_channel_layouts(), &ctx->inputs[0]->out_channel_layouts); |
| 294 | ff_channel_layouts_ref(s->channel_layouts, &ctx->outputs[0]->in_channel_layouts); |
| 295 | |
| 296 | return 0; |
| 297 | } |
| 298 | |
| 299 | static int channelmap_filter_frame(AVFilterLink *inlink, AVFrame *buf) |
| 300 | { |
| 301 | AVFilterContext *ctx = inlink->dst; |
| 302 | AVFilterLink *outlink = ctx->outputs[0]; |
| 303 | const ChannelMapContext *s = ctx->priv; |
| 304 | const int nch_in = av_get_channel_layout_nb_channels(inlink->channel_layout); |
| 305 | const int nch_out = s->nch; |
| 306 | int ch; |
| 307 | uint8_t *source_planes[MAX_CH]; |
| 308 | |
| 309 | memcpy(source_planes, buf->extended_data, |
| 310 | nch_in * sizeof(source_planes[0])); |
| 311 | |
| 312 | if (nch_out > nch_in) { |
| 313 | if (nch_out > FF_ARRAY_ELEMS(buf->data)) { |
| 314 | uint8_t **new_extended_data = |
| 315 | av_mallocz_array(nch_out, sizeof(*buf->extended_data)); |
| 316 | if (!new_extended_data) { |
| 317 | av_frame_free(&buf); |
| 318 | return AVERROR(ENOMEM); |
| 319 | } |
| 320 | if (buf->extended_data == buf->data) { |
| 321 | buf->extended_data = new_extended_data; |
| 322 | } else { |
| 323 | av_free(buf->extended_data); |
| 324 | buf->extended_data = new_extended_data; |
| 325 | } |
| 326 | } else if (buf->extended_data != buf->data) { |
| 327 | av_free(buf->extended_data); |
| 328 | buf->extended_data = buf->data; |
| 329 | } |
| 330 | } |
| 331 | |
| 332 | for (ch = 0; ch < nch_out; ch++) { |
| 333 | buf->extended_data[s->map[ch].out_channel_idx] = |
| 334 | source_planes[s->map[ch].in_channel_idx]; |
| 335 | } |
| 336 | |
| 337 | if (buf->data != buf->extended_data) |
| 338 | memcpy(buf->data, buf->extended_data, |
| 339 | FFMIN(FF_ARRAY_ELEMS(buf->data), nch_out) * sizeof(buf->data[0])); |
| 340 | |
| 341 | buf->channel_layout = outlink->channel_layout; |
| 342 | |
| 343 | return ff_filter_frame(outlink, buf); |
| 344 | } |
| 345 | |
| 346 | static int channelmap_config_input(AVFilterLink *inlink) |
| 347 | { |
| 348 | AVFilterContext *ctx = inlink->dst; |
| 349 | ChannelMapContext *s = ctx->priv; |
| 350 | int nb_channels = av_get_channel_layout_nb_channels(inlink->channel_layout); |
| 351 | int i, err = 0; |
| 352 | const char *channel_name; |
| 353 | char layout_name[256]; |
| 354 | |
| 355 | for (i = 0; i < s->nch; i++) { |
| 356 | struct ChannelMap *m = &s->map[i]; |
| 357 | |
| 358 | if (s->mode == MAP_PAIR_STR_INT || s->mode == MAP_PAIR_STR_STR) { |
| 359 | m->in_channel_idx = av_get_channel_layout_channel_index( |
| 360 | inlink->channel_layout, m->in_channel); |
| 361 | } |
| 362 | |
| 363 | if (m->in_channel_idx < 0 || m->in_channel_idx >= nb_channels) { |
| 364 | av_get_channel_layout_string(layout_name, sizeof(layout_name), |
| 365 | 0, inlink->channel_layout); |
| 366 | if (m->in_channel) { |
| 367 | channel_name = av_get_channel_name(m->in_channel); |
| 368 | av_log(ctx, AV_LOG_ERROR, |
| 369 | "input channel '%s' not available from input layout '%s'\n", |
| 370 | channel_name, layout_name); |
| 371 | } else { |
| 372 | av_log(ctx, AV_LOG_ERROR, |
| 373 | "input channel #%d not available from input layout '%s'\n", |
| 374 | m->in_channel_idx, layout_name); |
| 375 | } |
| 376 | err = AVERROR(EINVAL); |
| 377 | } |
| 378 | } |
| 379 | |
| 380 | return err; |
| 381 | } |
| 382 | |
| 383 | static const AVFilterPad avfilter_af_channelmap_inputs[] = { |
| 384 | { |
| 385 | .name = "default", |
| 386 | .type = AVMEDIA_TYPE_AUDIO, |
| 387 | .filter_frame = channelmap_filter_frame, |
| 388 | .config_props = channelmap_config_input, |
| 389 | .needs_writable = 1, |
| 390 | }, |
| 391 | { NULL } |
| 392 | }; |
| 393 | |
| 394 | static const AVFilterPad avfilter_af_channelmap_outputs[] = { |
| 395 | { |
| 396 | .name = "default", |
| 397 | .type = AVMEDIA_TYPE_AUDIO |
| 398 | }, |
| 399 | { NULL } |
| 400 | }; |
| 401 | |
| 402 | AVFilter ff_af_channelmap = { |
| 403 | .name = "channelmap", |
| 404 | .description = NULL_IF_CONFIG_SMALL("Remap audio channels."), |
| 405 | .init = channelmap_init, |
| 406 | .query_formats = channelmap_query_formats, |
| 407 | .priv_size = sizeof(ChannelMapContext), |
| 408 | .priv_class = &channelmap_class, |
| 409 | .inputs = avfilter_af_channelmap_inputs, |
| 410 | .outputs = avfilter_af_channelmap_outputs, |
| 411 | }; |