ffmpeg/libavfilter/af_join.c

   1 /*
   2  * This file is part of FFmpeg.
   3  *
   4  * FFmpeg is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * FFmpeg is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with FFmpeg; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17  */
  18
  19 /**
  20  * @file
  21  * Audio join filter
  22  *
  23  * Join multiple audio inputs as different channels in
  24  * a single output
  25  */
  26
  27 #include "libavutil/avassert.h"
  28 #include "libavutil/channel_layout.h"
  29 #include "libavutil/common.h"
  30 #include "libavutil/opt.h"
  31
  32 #include "audio.h"
  33 #include "avfilter.h"
  34 #include "formats.h"
  35 #include "internal.h"
  36
  37 typedef struct ChannelMap {
  38     int input;                ///< input stream index
  39     int       in_channel_idx; ///< index of in_channel in the input stream data
  40     uint64_t  in_channel;     ///< layout describing the input channel
  41     uint64_t out_channel;     ///< layout describing the output channel
  42 } ChannelMap;
  43
  44 typedef struct JoinContext {
  45     const AVClass *class;
  46
  47     int inputs;
  48     char *map;
  49     char    *channel_layout_str;
  50     uint64_t channel_layout;
  51
  52     int      nb_channels;
  53     ChannelMap *channels;
  54
  55     /**
  56      * Temporary storage for input frames, until we get one on each input.
  57      */
  58     AVFrame **input_frames;
  59
  60     /**
  61      *  Temporary storage for buffer references, for assembling the output frame.
  62      */
  63     AVBufferRef **buffers;
  64 } JoinContext;
  65
  66 #define OFFSET(x) offsetof(JoinContext, x)
  67 #define A AV_OPT_FLAG_AUDIO_PARAM
  68 #define F AV_OPT_FLAG_FILTERING_PARAM
  69 static const AVOption join_options[] = {
  70     { "inputs",         "Number of input streams.", OFFSET(inputs),             AV_OPT_TYPE_INT,    { .i64 = 2 }, 1, INT_MAX,       A|F },
  71     { "channel_layout", "Channel layout of the "
  72                         "output stream.",           OFFSET(channel_layout_str), AV_OPT_TYPE_STRING, {.str = "stereo"}, 0, 0, A|F },
  73     { "map",            "A comma-separated list of channels maps in the format "
  74                         "'input_stream.input_channel-output_channel.",
  75                                                     OFFSET(map),                AV_OPT_TYPE_STRING,                 .flags = A|F },
  76     { NULL }
  77 };
  78
  79 AVFILTER_DEFINE_CLASS(join);
  80
  81 static int filter_frame(AVFilterLink *link, AVFrame *frame)
  82 {
  83     AVFilterContext *ctx = link->dst;
  84     JoinContext       *s = ctx->priv;
  85     int i;
  86
  87     for (i = 0; i < ctx->nb_inputs; i++)
  88         if (link == ctx->inputs[i])
  89             break;
  90     av_assert0(i < ctx->nb_inputs);
  91     av_assert0(!s->input_frames[i]);
  92     s->input_frames[i] = frame;
  93
  94     return 0;
  95 }
  96
  97 static int parse_maps(AVFilterContext *ctx)
  98 {
  99     JoinContext *s = ctx->priv;
 100     char separator = '|';
 101     char *cur      = s->map;
 102
 103 #if FF_API_OLD_FILTER_OPTS
 104     if (cur && strchr(cur, ',')) {
 105         av_log(ctx, AV_LOG_WARNING, "This syntax is deprecated, use '|' to "
 106                "separate the mappings.\n");
 107         separator = ',';
 108     }
 109 #endif
 110
 111     while (cur && *cur) {
 112         char *sep, *next, *p;
 113         uint64_t in_channel = 0, out_channel = 0;
 114         int input_idx, out_ch_idx, in_ch_idx;
 115
 116         next = strchr(cur, separator);
 117         if (next)
 118             *next++ = 0;
 119
 120         /* split the map into input and output parts */
 121         if (!(sep = strchr(cur, '-'))) {
 122             av_log(ctx, AV_LOG_ERROR, "Missing separator '-' in channel "
 123                    "map '%s'\n", cur);
 124             return AVERROR(EINVAL);
 125         }
 126         *sep++ = 0;
 127
 128 #define PARSE_CHANNEL(str, var, inout)                                         \
 129         if (!(var = av_get_channel_layout(str))) {                             \
 130             av_log(ctx, AV_LOG_ERROR, "Invalid " inout " channel: %s.\n", str);\
 131             return AVERROR(EINVAL);                                            \
 132         }                                                                      \
 133         if (av_get_channel_layout_nb_channels(var) != 1) {                     \
 134             av_log(ctx, AV_LOG_ERROR, "Channel map describes more than one "   \
 135                    inout " channel.\n");                                       \
 136             return AVERROR(EINVAL);                                            \
 137         }
 138
 139         /* parse output channel */
 140         PARSE_CHANNEL(sep, out_channel, "output");
 141         if (!(out_channel & s->channel_layout)) {
 142             av_log(ctx, AV_LOG_ERROR, "Output channel '%s' is not present in "
 143                    "requested channel layout.\n", sep);
 144             return AVERROR(EINVAL);
 145         }
 146
 147         out_ch_idx = av_get_channel_layout_channel_index(s->channel_layout,
 148                                                          out_channel);
 149         if (s->channels[out_ch_idx].input >= 0) {
 150             av_log(ctx, AV_LOG_ERROR, "Multiple maps for output channel "
 151                    "'%s'.\n", sep);
 152             return AVERROR(EINVAL);
 153         }
 154
 155         /* parse input channel */
 156         input_idx = strtol(cur, &cur, 0);
 157         if (input_idx < 0 || input_idx >= s->inputs) {
 158             av_log(ctx, AV_LOG_ERROR, "Invalid input stream index: %d.\n",
 159                    input_idx);
 160             return AVERROR(EINVAL);
 161         }
 162
 163         if (*cur)
 164             cur++;
 165
 166         in_ch_idx = strtol(cur, &p, 0);
 167         if (p == cur) {
 168             /* channel specifier is not a number,
 169              * try to parse as channel name */
 170             PARSE_CHANNEL(cur, in_channel, "input");
 171         }
 172
 173         s->channels[out_ch_idx].input      = input_idx;
 174         if (in_channel)
 175             s->channels[out_ch_idx].in_channel = in_channel;
 176         else
 177             s->channels[out_ch_idx].in_channel_idx = in_ch_idx;
 178
 179         cur = next;
 180     }
 181     return 0;
 182 }
 183
 184 static av_cold int join_init(AVFilterContext *ctx)
 185 {
 186     JoinContext *s = ctx->priv;
 187     int ret, i;
 188
 189     if (!(s->channel_layout = av_get_channel_layout(s->channel_layout_str))) {
 190         av_log(ctx, AV_LOG_ERROR, "Error parsing channel layout '%s'.\n",
 191                s->channel_layout_str);
 192         return AVERROR(EINVAL);
 193     }
 194
 195     s->nb_channels  = av_get_channel_layout_nb_channels(s->channel_layout);
 196     s->channels     = av_mallocz(sizeof(*s->channels) * s->nb_channels);
 197     s->buffers      = av_mallocz(sizeof(*s->buffers)  * s->nb_channels);
 198     s->input_frames = av_mallocz(sizeof(*s->input_frames) * s->inputs);
 199     if (!s->channels || !s->buffers|| !s->input_frames)
 200         return AVERROR(ENOMEM);
 201
 202     for (i = 0; i < s->nb_channels; i++) {
 203         s->channels[i].out_channel = av_channel_layout_extract_channel(s->channel_layout, i);
 204         s->channels[i].input       = -1;
 205     }
 206
 207     if ((ret = parse_maps(ctx)) < 0)
 208         return ret;
 209
 210     for (i = 0; i < s->inputs; i++) {
 211         char name[32];
 212         AVFilterPad pad = { 0 };
 213
 214         snprintf(name, sizeof(name), "input%d", i);
 215         pad.type           = AVMEDIA_TYPE_AUDIO;
 216         pad.name           = av_strdup(name);
 217         if (!pad.name)
 218             return AVERROR(ENOMEM);
 219         pad.filter_frame   = filter_frame;
 220
 221         pad.needs_fifo = 1;
 222
 223         ff_insert_inpad(ctx, i, &pad);
 224     }
 225
 226     return 0;
 227 }
 228
 229 static av_cold void join_uninit(AVFilterContext *ctx)
 230 {
 231     JoinContext *s = ctx->priv;
 232     int i;
 233
 234     for (i = 0; i < ctx->nb_inputs; i++) {
 235         av_freep(&ctx->input_pads[i].name);
 236         av_frame_free(&s->input_frames[i]);
 237     }
 238
 239     av_freep(&s->channels);
 240     av_freep(&s->buffers);
 241     av_freep(&s->input_frames);
 242 }
 243
 244 static int join_query_formats(AVFilterContext *ctx)
 245 {
 246     JoinContext *s = ctx->priv;
 247     AVFilterChannelLayouts *layouts = NULL;
 248     int i;
 249
 250     ff_add_channel_layout(&layouts, s->channel_layout);
 251     ff_channel_layouts_ref(layouts, &ctx->outputs[0]->in_channel_layouts);
 252
 253     for (i = 0; i < ctx->nb_inputs; i++) {
 254         layouts = ff_all_channel_layouts();
 255         if (!layouts)
 256             return AVERROR(ENOMEM);
 257         ff_channel_layouts_ref(layouts, &ctx->inputs[i]->out_channel_layouts);
 258     }
 259
 260     ff_set_common_formats    (ctx, ff_planar_sample_fmts());
 261     ff_set_common_samplerates(ctx, ff_all_samplerates());
 262
 263     return 0;
 264 }
 265
 266 static void guess_map_matching(AVFilterContext *ctx, ChannelMap *ch,
 267                                uint64_t *inputs)
 268 {
 269     int i;
 270
 271     for (i = 0; i < ctx->nb_inputs; i++) {
 272         AVFilterLink *link = ctx->inputs[i];
 273
 274         if (ch->out_channel & link->channel_layout &&
 275             !(ch->out_channel & inputs[i])) {
 276             ch->input      = i;
 277             ch->in_channel = ch->out_channel;
 278             inputs[i]     |= ch->out_channel;
 279             return;
 280         }
 281     }
 282 }
 283
 284 static void guess_map_any(AVFilterContext *ctx, ChannelMap *ch,
 285                           uint64_t *inputs)
 286 {
 287     int i;
 288
 289     for (i = 0; i < ctx->nb_inputs; i++) {
 290         AVFilterLink *link = ctx->inputs[i];
 291
 292         if ((inputs[i] & link->channel_layout) != link->channel_layout) {
 293             uint64_t unused = link->channel_layout & ~inputs[i];
 294
 295             ch->input      = i;
 296             ch->in_channel = av_channel_layout_extract_channel(unused, 0);
 297             inputs[i]     |= ch->in_channel;
 298             return;
 299         }
 300     }
 301 }
 302
 303 static int join_config_output(AVFilterLink *outlink)
 304 {
 305     AVFilterContext *ctx = outlink->src;
 306     JoinContext       *s = ctx->priv;
 307     uint64_t *inputs;   // nth element tracks which channels are used from nth input
 308     int i, ret = 0;
 309
 310     /* initialize inputs to user-specified mappings */
 311     if (!(inputs = av_mallocz(sizeof(*inputs) * ctx->nb_inputs)))
 312         return AVERROR(ENOMEM);
 313     for (i = 0; i < s->nb_channels; i++) {
 314         ChannelMap *ch = &s->channels[i];
 315         AVFilterLink *inlink;
 316
 317         if (ch->input < 0)
 318             continue;
 319
 320         inlink = ctx->inputs[ch->input];
 321
 322         if (!ch->in_channel)
 323             ch->in_channel = av_channel_layout_extract_channel(inlink->channel_layout,
 324                                                                ch->in_channel_idx);
 325
 326         if (!(ch->in_channel & inlink->channel_layout)) {
 327             av_log(ctx, AV_LOG_ERROR, "Requested channel %s is not present in "
 328                    "input stream #%d.\n", av_get_channel_name(ch->in_channel),
 329                    ch->input);
 330             ret = AVERROR(EINVAL);
 331             goto fail;
 332         }
 333
 334         inputs[ch->input] |= ch->in_channel;
 335     }
 336
 337     /* guess channel maps when not explicitly defined */
 338     /* first try unused matching channels */
 339     for (i = 0; i < s->nb_channels; i++) {
 340         ChannelMap *ch = &s->channels[i];
 341
 342         if (ch->input < 0)
 343             guess_map_matching(ctx, ch, inputs);
 344     }
 345
 346     /* if the above failed, try to find _any_ unused input channel */
 347     for (i = 0; i < s->nb_channels; i++) {
 348         ChannelMap *ch = &s->channels[i];
 349
 350         if (ch->input < 0)
 351             guess_map_any(ctx, ch, inputs);
 352
 353         if (ch->input < 0) {
 354             av_log(ctx, AV_LOG_ERROR, "Could not find input channel for "
 355                    "output channel '%s'.\n",
 356                    av_get_channel_name(ch->out_channel));
 357             goto fail;
 358         }
 359
 360         ch->in_channel_idx = av_get_channel_layout_channel_index(ctx->inputs[ch->input]->channel_layout,
 361                                                                  ch->in_channel);
 362     }
 363
 364     /* print mappings */
 365     av_log(ctx, AV_LOG_VERBOSE, "mappings: ");
 366     for (i = 0; i < s->nb_channels; i++) {
 367         ChannelMap *ch = &s->channels[i];
 368         av_log(ctx, AV_LOG_VERBOSE, "%d.%s => %s ", ch->input,
 369                av_get_channel_name(ch->in_channel),
 370                av_get_channel_name(ch->out_channel));
 371     }
 372     av_log(ctx, AV_LOG_VERBOSE, "\n");
 373
 374     for (i = 0; i < ctx->nb_inputs; i++) {
 375         if (!inputs[i])
 376             av_log(ctx, AV_LOG_WARNING, "No channels are used from input "
 377                    "stream %d.\n", i);
 378     }
 379
 380 fail:
 381     av_freep(&inputs);
 382     return ret;
 383 }
 384
 385 static int join_request_frame(AVFilterLink *outlink)
 386 {
 387     AVFilterContext *ctx = outlink->src;
 388     JoinContext *s       = ctx->priv;
 389     AVFrame *frame;
 390     int linesize   = INT_MAX;
 391     int nb_samples = 0;
 392     int nb_buffers = 0;
 393     int i, j, ret;
 394
 395     /* get a frame on each input */
 396     for (i = 0; i < ctx->nb_inputs; i++) {
 397         AVFilterLink *inlink = ctx->inputs[i];
 398
 399         if (!s->input_frames[i] &&
 400             (ret = ff_request_frame(inlink)) < 0)
 401             return ret;
 402
 403         /* request the same number of samples on all inputs */
 404         if (i == 0) {
 405             nb_samples = s->input_frames[0]->nb_samples;
 406
 407             for (j = 1; !i && j < ctx->nb_inputs; j++)
 408                 ctx->inputs[j]->request_samples = nb_samples;
 409         }
 410     }
 411
 412     /* setup the output frame */
 413     frame = av_frame_alloc();
 414     if (!frame)
 415         return AVERROR(ENOMEM);
 416     if (s->nb_channels > FF_ARRAY_ELEMS(frame->data)) {
 417         frame->extended_data = av_mallocz(s->nb_channels *
 418                                           sizeof(*frame->extended_data));
 419         if (!frame->extended_data) {
 420             ret = AVERROR(ENOMEM);
 421             goto fail;
 422         }
 423     }
 424
 425     /* copy the data pointers */
 426     for (i = 0; i < s->nb_channels; i++) {
 427         ChannelMap *ch = &s->channels[i];
 428         AVFrame *cur   = s->input_frames[ch->input];
 429         AVBufferRef *buf;
 430
 431         frame->extended_data[i] = cur->extended_data[ch->in_channel_idx];
 432         linesize = FFMIN(linesize, cur->linesize[0]);
 433
 434         /* add the buffer where this plan is stored to the list if it's
 435          * not already there */
 436         buf = av_frame_get_plane_buffer(cur, ch->in_channel_idx);
 437         if (!buf) {
 438             ret = AVERROR(EINVAL);
 439             goto fail;
 440         }
 441         for (j = 0; j < nb_buffers; j++)
 442             if (s->buffers[j]->buffer == buf->buffer)
 443                 break;
 444         if (j == i)
 445             s->buffers[nb_buffers++] = buf;
 446     }
 447
 448     /* create references to the buffers we copied to output */
 449     if (nb_buffers > FF_ARRAY_ELEMS(frame->buf)) {
 450         frame->nb_extended_buf = nb_buffers - FF_ARRAY_ELEMS(frame->buf);
 451         frame->extended_buf = av_mallocz(sizeof(*frame->extended_buf) *
 452                                          frame->nb_extended_buf);
 453         if (!frame->extended_buf) {
 454             frame->nb_extended_buf = 0;
 455             ret = AVERROR(ENOMEM);
 456             goto fail;
 457         }
 458     }
 459     for (i = 0; i < FFMIN(FF_ARRAY_ELEMS(frame->buf), nb_buffers); i++) {
 460         frame->buf[i] = av_buffer_ref(s->buffers[i]);
 461         if (!frame->buf[i]) {
 462             ret = AVERROR(ENOMEM);
 463             goto fail;
 464         }
 465     }
 466     for (i = 0; i < frame->nb_extended_buf; i++) {
 467         frame->extended_buf[i] = av_buffer_ref(s->buffers[i +
 468                                                FF_ARRAY_ELEMS(frame->buf)]);
 469         if (!frame->extended_buf[i]) {
 470             ret = AVERROR(ENOMEM);
 471             goto fail;
 472         }
 473     }
 474
 475     frame->nb_samples     = nb_samples;
 476     frame->channel_layout = outlink->channel_layout;
 477     av_frame_set_channels(frame, outlink->channels);
 478     frame->sample_rate    = outlink->sample_rate;
 479     frame->format         = outlink->format;
 480     frame->pts            = s->input_frames[0]->pts;
 481     frame->linesize[0]    = linesize;
 482     if (frame->data != frame->extended_data) {
 483         memcpy(frame->data, frame->extended_data, sizeof(*frame->data) *
 484                FFMIN(FF_ARRAY_ELEMS(frame->data), s->nb_channels));
 485     }
 486
 487     ret = ff_filter_frame(outlink, frame);
 488
 489     for (i = 0; i < ctx->nb_inputs; i++)
 490         av_frame_free(&s->input_frames[i]);
 491
 492     return ret;
 493
 494 fail:
 495     av_frame_free(&frame);
 496     return ret;
 497 }
 498
 499 static const AVFilterPad avfilter_af_join_outputs[] = {
 500     {
 501         .name          = "default",
 502         .type          = AVMEDIA_TYPE_AUDIO,
 503         .config_props  = join_config_output,
 504         .request_frame = join_request_frame,
 505     },
 506     { NULL }
 507 };
 508
 509 AVFilter ff_af_join = {
 510     .name           = "join",
 511     .description    = NULL_IF_CONFIG_SMALL("Join multiple audio streams into "
 512                                            "multi-channel output."),
 513     .priv_size      = sizeof(JoinContext),
 514     .priv_class     = &join_class,
 515     .init           = join_init,
 516     .uninit         = join_uninit,
 517     .query_formats  = join_query_formats,
 518     .inputs         = NULL,
 519     .outputs        = avfilter_af_join_outputs,
 520     .flags          = AVFILTER_FLAG_DYNAMIC_INPUTS,
 521 };