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 40struct ChannelMap { 41 uint64_t in_channel; 42 uint64_t out_channel; 43 int in_channel_idx; 44 int out_channel_idx; 45}; 46 47enum 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 58typedef 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 72static 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 80AVFILTER_DEFINE_CLASS(channelmap); 81 82static char* split(char *message, char delim) { 83 char *next = strchr(message, delim); 84 if (next) 85 *next++ = '\0'; 86 return next; 87} 88 89static 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 106static 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 118static 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 287static 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 299static 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 return ff_filter_frame(outlink, buf); 342} 343 344static int channelmap_config_input(AVFilterLink *inlink) 345{ 346 AVFilterContext *ctx = inlink->dst; 347 ChannelMapContext *s = ctx->priv; 348 int nb_channels = av_get_channel_layout_nb_channels(inlink->channel_layout); 349 int i, err = 0; 350 const char *channel_name; 351 char layout_name[256]; 352 353 for (i = 0; i < s->nch; i++) { 354 struct ChannelMap *m = &s->map[i]; 355 356 if (s->mode == MAP_PAIR_STR_INT || s->mode == MAP_PAIR_STR_STR) { 357 m->in_channel_idx = av_get_channel_layout_channel_index( 358 inlink->channel_layout, m->in_channel); 359 } 360 361 if (m->in_channel_idx < 0 || m->in_channel_idx >= nb_channels) { 362 av_get_channel_layout_string(layout_name, sizeof(layout_name), 363 0, inlink->channel_layout); 364 if (m->in_channel) { 365 channel_name = av_get_channel_name(m->in_channel); 366 av_log(ctx, AV_LOG_ERROR, 367 "input channel '%s' not available from input layout '%s'\n", 368 channel_name, layout_name); 369 } else { 370 av_log(ctx, AV_LOG_ERROR, 371 "input channel #%d not available from input layout '%s'\n", 372 m->in_channel_idx, layout_name); 373 } 374 err = AVERROR(EINVAL); 375 } 376 } 377 378 return err; 379} 380 381static const AVFilterPad avfilter_af_channelmap_inputs[] = { 382 { 383 .name = "default", 384 .type = AVMEDIA_TYPE_AUDIO, 385 .filter_frame = channelmap_filter_frame, 386 .config_props = channelmap_config_input, 387 .needs_writable = 1, 388 }, 389 { NULL } 390}; 391 392static const AVFilterPad avfilter_af_channelmap_outputs[] = { 393 { 394 .name = "default", 395 .type = AVMEDIA_TYPE_AUDIO 396 }, 397 { NULL } 398}; 399 400AVFilter ff_af_channelmap = { 401 .name = "channelmap", 402 .description = NULL_IF_CONFIG_SMALL("Remap audio channels."), 403 .init = channelmap_init, 404 .query_formats = channelmap_query_formats, 405 .priv_size = sizeof(ChannelMapContext), 406 .priv_class = &channelmap_class, 407 .inputs = avfilter_af_channelmap_inputs, 408 .outputs = avfilter_af_channelmap_outputs, 409}; 410