libavformat/sdp.c

   1 /*
   2  * copyright (c) 2007 Luca Abeni
   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 #include <string.h>
  22 #include "libavutil/avstring.h"
  23 #include "libavutil/base64.h"
  24 #include "libavutil/dict.h"
  25 #include "libavutil/parseutils.h"
  26 #include "libavutil/opt.h"
  27 #include "libavcodec/xiph.h"
  28 #include "libavcodec/mpeg4audio.h"
  29 #include "avformat.h"
  30 #include "internal.h"
  31 #include "avc.h"
  32 #include "hevc.h"
  33 #include "rtp.h"
  34 #if CONFIG_NETWORK
  35 #include "network.h"
  36 #endif
  37
  38 #if CONFIG_RTP_MUXER
  39 #define MAX_EXTRADATA_SIZE ((INT_MAX - 10) / 2)
  40
  41 struct sdp_session_level {
  42     int sdp_version;      /**< protocol version (currently 0) */
  43     int id;               /**< session ID */
  44     int version;          /**< session version */
  45     int start_time;       /**< session start time (NTP time, in seconds),
  46                                or 0 in case of permanent session */
  47     int end_time;         /**< session end time (NTP time, in seconds),
  48                                or 0 if the session is not bounded */
  49     int ttl;              /**< TTL, in case of multicast stream */
  50     const char *user;     /**< username of the session's creator */
  51     const char *src_addr; /**< IP address of the machine from which the session was created */
  52     const char *src_type; /**< address type of src_addr */
  53     const char *dst_addr; /**< destination IP address (can be multicast) */
  54     const char *dst_type; /**< destination IP address type */
  55     const char *name;     /**< session name (can be an empty string) */
  56 };
  57
  58 static void sdp_write_address(char *buff, int size, const char *dest_addr,
  59                               const char *dest_type, int ttl)
  60 {
  61     if (dest_addr) {
  62         if (!dest_type)
  63             dest_type = "IP4";
  64         if (ttl > 0 && !strcmp(dest_type, "IP4")) {
  65             /* The TTL should only be specified for IPv4 multicast addresses,
  66              * not for IPv6. */
  67             av_strlcatf(buff, size, "c=IN %s %s/%d\r\n", dest_type, dest_addr, ttl);
  68         } else {
  69             av_strlcatf(buff, size, "c=IN %s %s\r\n", dest_type, dest_addr);
  70         }
  71     }
  72 }
  73
  74 static void sdp_write_header(char *buff, int size, struct sdp_session_level *s)
  75 {
  76     av_strlcatf(buff, size, "v=%d\r\n"
  77                             "o=- %d %d IN %s %s\r\n"
  78                             "s=%s\r\n",
  79                             s->sdp_version,
  80                             s->id, s->version, s->src_type, s->src_addr,
  81                             s->name);
  82     sdp_write_address(buff, size, s->dst_addr, s->dst_type, s->ttl);
  83     av_strlcatf(buff, size, "t=%d %d\r\n"
  84                             "a=tool:libavformat " AV_STRINGIFY(LIBAVFORMAT_VERSION) "\r\n",
  85                             s->start_time, s->end_time);
  86 }
  87
  88 #if CONFIG_NETWORK
  89 static int resolve_destination(char *dest_addr, int size, char *type,
  90                                int type_size)
  91 {
  92     struct addrinfo hints = { 0 }, *ai;
  93     int is_multicast;
  94
  95     av_strlcpy(type, "IP4", type_size);
  96     if (!dest_addr[0])
  97         return 0;
  98
  99     /* Resolve the destination, since it must be written
 100      * as a numeric IP address in the SDP. */
 101
 102     if (getaddrinfo(dest_addr, NULL, &hints, &ai))
 103         return 0;
 104     getnameinfo(ai->ai_addr, ai->ai_addrlen, dest_addr, size,
 105                 NULL, 0, NI_NUMERICHOST);
 106 #ifdef AF_INET6
 107     if (ai->ai_family == AF_INET6)
 108         av_strlcpy(type, "IP6", type_size);
 109 #endif
 110     is_multicast = ff_is_multicast_address(ai->ai_addr);
 111     freeaddrinfo(ai);
 112     return is_multicast;
 113 }
 114 #else
 115 static int resolve_destination(char *dest_addr, int size, char *type,
 116                                int type_size)
 117 {
 118     return 0;
 119 }
 120 #endif
 121
 122 static int sdp_get_address(char *dest_addr, int size, int *ttl, const char *url)
 123 {
 124     int port;
 125     const char *p;
 126     char proto[32];
 127
 128     av_url_split(proto, sizeof(proto), NULL, 0, dest_addr, size, &port, NULL, 0, url);
 129
 130     *ttl = 0;
 131
 132     if (strcmp(proto, "rtp") && strcmp(proto, "srtp")) {
 133         /* The url isn't for the actual rtp sessions,
 134          * don't parse out anything else than the destination.
 135          */
 136         return 0;
 137     }
 138
 139     p = strchr(url, '?');
 140     if (p) {
 141         char buff[64];
 142
 143         if (av_find_info_tag(buff, sizeof(buff), "ttl", p)) {
 144             *ttl = strtol(buff, NULL, 10);
 145         } else {
 146             *ttl = 5;
 147         }
 148     }
 149
 150     return port;
 151 }
 152
 153 #define MAX_PSET_SIZE 1024
 154 static char *extradata2psets(AVFormatContext *s, AVCodecParameters *par)
 155 {
 156     char *psets, *p;
 157     const uint8_t *r;
 158     static const char pset_string[] = "; sprop-parameter-sets=";
 159     static const char profile_string[] = "; profile-level-id=";
 160     uint8_t *extradata = par->extradata;
 161     int extradata_size = par->extradata_size;
 162     uint8_t *tmpbuf = NULL;
 163     const uint8_t *sps = NULL, *sps_end;
 164
 165     if (par->extradata_size > MAX_EXTRADATA_SIZE) {
 166         av_log(s, AV_LOG_ERROR, "Too much extradata!\n");
 167
 168         return NULL;
 169     }
 170     if (par->extradata[0] == 1) {
 171         if (ff_avc_write_annexb_extradata(par->extradata, &extradata,
 172                                           &extradata_size))
 173             return NULL;
 174         tmpbuf = extradata;
 175     }
 176
 177     psets = av_mallocz(MAX_PSET_SIZE);
 178     if (!psets) {
 179         av_log(s, AV_LOG_ERROR, "Cannot allocate memory for the parameter sets.\n");
 180         av_free(tmpbuf);
 181         return NULL;
 182     }
 183     memcpy(psets, pset_string, strlen(pset_string));
 184     p = psets + strlen(pset_string);
 185     r = ff_avc_find_startcode(extradata, extradata + extradata_size);
 186     while (r < extradata + extradata_size) {
 187         const uint8_t *r1;
 188         uint8_t nal_type;
 189
 190         while (!*(r++));
 191         nal_type = *r & 0x1f;
 192         r1 = ff_avc_find_startcode(r, extradata + extradata_size);
 193         if (nal_type != 7 && nal_type != 8) { /* Only output SPS and PPS */
 194             r = r1;
 195             continue;
 196         }
 197         if (p != (psets + strlen(pset_string))) {
 198             if (p - psets >= MAX_PSET_SIZE)
 199                 goto fail_in_loop;
 200             *p = ',';
 201             p++;
 202         }
 203         if (!sps) {
 204             sps = r;
 205             sps_end = r1;
 206         }
 207         if (!av_base64_encode(p, MAX_PSET_SIZE - (p - psets), r, r1 - r)) {
 208             av_log(s, AV_LOG_ERROR, "Cannot Base64-encode %"PTRDIFF_SPECIFIER" %"PTRDIFF_SPECIFIER"!\n", MAX_PSET_SIZE - (p - psets), r1 - r);
 209 fail_in_loop:
 210             av_free(psets);
 211             av_free(tmpbuf);
 212
 213             return NULL;
 214         }
 215         p += strlen(p);
 216         r = r1;
 217     }
 218     if (sps && sps_end - sps >= 4 && p - psets <= MAX_PSET_SIZE - strlen(profile_string) - 7) {
 219         memcpy(p, profile_string, strlen(profile_string));
 220         p += strlen(p);
 221         ff_data_to_hex(p, sps + 1, 3, 0);
 222         p[6] = '\0';
 223     }
 224     av_free(tmpbuf);
 225
 226     return psets;
 227 }
 228
 229 static char *extradata2psets_hevc(AVCodecParameters *par)
 230 {
 231     char *psets;
 232     uint8_t *extradata = par->extradata;
 233     int extradata_size = par->extradata_size;
 234     uint8_t *tmpbuf = NULL;
 235     int ps_pos[3] = { 0 };
 236     static const char * const ps_names[3] = { "vps", "sps", "pps" };
 237     int num_arrays, num_nalus;
 238     int pos, i, j;
 239
 240     // Convert to hvcc format. Since we need to group multiple NALUs of
 241     // the same type, and we might need to convert from one format to the
 242     // other anyway, we get away with a little less work by using the hvcc
 243     // format.
 244     if (par->extradata[0] != 1) {
 245         AVIOContext *pb;
 246         if (avio_open_dyn_buf(&pb) < 0)
 247             return NULL;
 248         if (ff_isom_write_hvcc(pb, par->extradata, par->extradata_size, 0) < 0) {
 249             avio_close_dyn_buf(pb, &tmpbuf);
 250             goto err;
 251         }
 252         extradata_size = avio_close_dyn_buf(pb, &extradata);
 253         tmpbuf = extradata;
 254     }
 255
 256     if (extradata_size < 23)
 257         goto err;
 258
 259     num_arrays = extradata[22];
 260     pos = 23;
 261     for (i = 0; i < num_arrays; i++) {
 262         int num_nalus, nalu_type;
 263         if (pos + 3 > extradata_size)
 264             goto err;
 265         nalu_type = extradata[pos] & 0x3f;
 266         // Not including libavcodec/hevc.h to avoid confusion between
 267         // NAL_* with the same name for both H.264 and HEVC.
 268         if (nalu_type == 32) // VPS
 269             ps_pos[0] = pos;
 270         else if (nalu_type == 33) // SPS
 271             ps_pos[1] = pos;
 272         else if (nalu_type == 34) // PPS
 273             ps_pos[2] = pos;
 274         num_nalus = AV_RB16(&extradata[pos + 1]);
 275         pos += 3;
 276         for (j = 0; j < num_nalus; j++) {
 277             int len;
 278             if (pos + 2 > extradata_size)
 279                 goto err;
 280             len = AV_RB16(&extradata[pos]);
 281             pos += 2;
 282             if (pos + len > extradata_size)
 283                 goto err;
 284             pos += len;
 285         }
 286     }
 287     if (!ps_pos[0] || !ps_pos[1] || !ps_pos[2])
 288         goto err;
 289
 290     psets = av_mallocz(MAX_PSET_SIZE);
 291     if (!psets)
 292         goto err;
 293     psets[0] = '\0';
 294
 295     for (i = 0; i < 3; i++) {
 296         pos = ps_pos[i];
 297
 298         if (i > 0)
 299             av_strlcat(psets, "; ", MAX_PSET_SIZE);
 300         av_strlcatf(psets, MAX_PSET_SIZE, "sprop-%s=", ps_names[i]);
 301
 302         // Skipping boundary checks in the input here; we've already traversed
 303         // the whole hvcc structure above without issues
 304         num_nalus = AV_RB16(&extradata[pos + 1]);
 305         pos += 3;
 306         for (j = 0; j < num_nalus; j++) {
 307             int len = AV_RB16(&extradata[pos]);
 308             int strpos;
 309             pos += 2;
 310             if (j > 0)
 311                 av_strlcat(psets, ",", MAX_PSET_SIZE);
 312             strpos = strlen(psets);
 313             if (!av_base64_encode(psets + strpos, MAX_PSET_SIZE - strpos,
 314                                   &extradata[pos], len)) {
 315                 av_free(psets);
 316                 goto err;
 317             }
 318             pos += len;
 319         }
 320     }
 321     av_free(tmpbuf);
 322
 323     return psets;
 324
 325 err:
 326     av_free(tmpbuf);
 327     return NULL;
 328 }
 329
 330 static char *extradata2config(AVFormatContext *s, AVCodecParameters *par)
 331 {
 332     char *config;
 333
 334     if (par->extradata_size > MAX_EXTRADATA_SIZE) {
 335         av_log(s, AV_LOG_ERROR, "Too much extradata!\n");
 336
 337         return NULL;
 338     }
 339     config = av_malloc(10 + par->extradata_size * 2);
 340     if (!config) {
 341         av_log(s, AV_LOG_ERROR, "Cannot allocate memory for the config info.\n");
 342         return NULL;
 343     }
 344     memcpy(config, "; config=", 9);
 345     ff_data_to_hex(config + 9, par->extradata, par->extradata_size, 0);
 346     config[9 + par->extradata_size * 2] = 0;
 347
 348     return config;
 349 }
 350
 351 static char *xiph_extradata2config(AVFormatContext *s, AVCodecParameters *par)
 352 {
 353     uint8_t *config;
 354     char *encoded_config;
 355     const uint8_t *header_start[3];
 356     int headers_len, header_len[3], config_len;
 357     int first_header_size;
 358
 359     switch (par->codec_id) {
 360     case AV_CODEC_ID_THEORA:
 361         first_header_size = 42;
 362         break;
 363     case AV_CODEC_ID_VORBIS:
 364         first_header_size = 30;
 365         break;
 366     default:
 367         av_log(s, AV_LOG_ERROR, "Unsupported Xiph codec ID\n");
 368         return NULL;
 369     }
 370
 371     if (avpriv_split_xiph_headers(par->extradata, par->extradata_size,
 372                               first_header_size, header_start,
 373                               header_len) < 0) {
 374         av_log(s, AV_LOG_ERROR, "Extradata corrupt.\n");
 375         return NULL;
 376     }
 377
 378     headers_len = header_len[0] + header_len[2];
 379     config_len = 4 +          // count
 380                  3 +          // ident
 381                  2 +          // packet size
 382                  1 +          // header count
 383                  2 +          // header size
 384                  headers_len; // and the rest
 385
 386     config = av_malloc(config_len);
 387     if (!config)
 388         goto xiph_fail;
 389
 390     encoded_config = av_malloc(AV_BASE64_SIZE(config_len));
 391     if (!encoded_config) {
 392         av_free(config);
 393         goto xiph_fail;
 394     }
 395
 396     config[0] = config[1] = config[2] = 0;
 397     config[3] = 1;
 398     config[4] = (RTP_XIPH_IDENT >> 16) & 0xff;
 399     config[5] = (RTP_XIPH_IDENT >>  8) & 0xff;
 400     config[6] = (RTP_XIPH_IDENT      ) & 0xff;
 401     config[7] = (headers_len >> 8) & 0xff;
 402     config[8] = headers_len & 0xff;
 403     config[9] = 2;
 404     config[10] = header_len[0];
 405     config[11] = 0; // size of comment header; nonexistent
 406     memcpy(config + 12, header_start[0], header_len[0]);
 407     memcpy(config + 12 + header_len[0], header_start[2], header_len[2]);
 408
 409     av_base64_encode(encoded_config, AV_BASE64_SIZE(config_len),
 410                      config, config_len);
 411     av_free(config);
 412
 413     return encoded_config;
 414
 415 xiph_fail:
 416     av_log(s, AV_LOG_ERROR,
 417            "Not enough memory for configuration string\n");
 418     return NULL;
 419 }
 420
 421 static int latm_context2profilelevel(AVCodecParameters *par)
 422 {
 423     /* MP4A-LATM
 424      * The RTP payload format specification is described in RFC 3016
 425      * The encoding specifications are provided in ISO/IEC 14496-3 */
 426
 427     int profile_level = 0x2B;
 428
 429     /* TODO: AAC Profile only supports AAC LC Object Type.
 430      * Different Object Types should implement different Profile Levels */
 431
 432     if (par->sample_rate <= 24000) {
 433         if (par->channels <= 2)
 434             profile_level = 0x28; // AAC Profile, Level 1
 435     } else if (par->sample_rate <= 48000) {
 436         if (par->channels <= 2) {
 437             profile_level = 0x29; // AAC Profile, Level 2
 438         } else if (par->channels <= 5) {
 439             profile_level = 0x2A; // AAC Profile, Level 4
 440         }
 441     } else if (par->sample_rate <= 96000) {
 442         if (par->channels <= 5) {
 443             profile_level = 0x2B; // AAC Profile, Level 5
 444         }
 445     }
 446
 447     return profile_level;
 448 }
 449
 450 static char *latm_context2config(AVFormatContext *s, AVCodecParameters *par)
 451 {
 452     /* MP4A-LATM
 453      * The RTP payload format specification is described in RFC 3016
 454      * The encoding specifications are provided in ISO/IEC 14496-3 */
 455
 456     uint8_t config_byte[6];
 457     int rate_index;
 458     char *config;
 459
 460     for (rate_index = 0; rate_index < 16; rate_index++)
 461         if (avpriv_mpeg4audio_sample_rates[rate_index] == par->sample_rate)
 462             break;
 463     if (rate_index == 16) {
 464         av_log(s, AV_LOG_ERROR, "Unsupported sample rate\n");
 465         return NULL;
 466     }
 467
 468     config_byte[0] = 0x40;
 469     config_byte[1] = 0;
 470     config_byte[2] = 0x20 | rate_index;
 471     config_byte[3] = par->channels << 4;
 472     config_byte[4] = 0x3f;
 473     config_byte[5] = 0xc0;
 474
 475     config = av_malloc(6*2+1);
 476     if (!config) {
 477         av_log(s, AV_LOG_ERROR, "Cannot allocate memory for the config info.\n");
 478         return NULL;
 479     }
 480     ff_data_to_hex(config, config_byte, 6, 1);
 481     config[12] = 0;
 482
 483     return config;
 484 }
 485
 486 static char *sdp_write_media_attributes(char *buff, int size, AVStream *st, int payload_type, AVFormatContext *fmt)
 487 {
 488     char *config = NULL;
 489     AVCodecParameters *p = st->codecpar;
 490
 491     switch (p->codec_id) {
 492         case AV_CODEC_ID_DIRAC:
 493             av_strlcatf(buff, size, "a=rtpmap:%d VC2/90000\r\n", payload_type);
 494             break;
 495         case AV_CODEC_ID_H264: {
 496             int mode = 1;
 497             if (fmt && fmt->oformat && fmt->oformat->priv_class &&
 498                 av_opt_flag_is_set(fmt->priv_data, "rtpflags", "h264_mode0"))
 499                 mode = 0;
 500             if (p->extradata_size) {
 501                 config = extradata2psets(fmt, p);
 502             }
 503             av_strlcatf(buff, size, "a=rtpmap:%d H264/90000\r\n"
 504                                     "a=fmtp:%d packetization-mode=%d%s\r\n",
 505                                      payload_type,
 506                                      payload_type, mode, config ? config : "");
 507             break;
 508         }
 509         case AV_CODEC_ID_H261:
 510         {
 511             const char *pic_fmt = NULL;
 512             /* only QCIF and CIF are specified as supported in RFC 4587 */
 513             if (p->width == 176 && p->height == 144)
 514                 pic_fmt = "QCIF=1";
 515             else if (p->width == 352 && p->height == 288)
 516                 pic_fmt = "CIF=1";
 517             if (payload_type >= RTP_PT_PRIVATE)
 518                 av_strlcatf(buff, size, "a=rtpmap:%d H261/90000\r\n", payload_type);
 519             if (pic_fmt)
 520                 av_strlcatf(buff, size, "a=fmtp:%d %s\r\n", payload_type, pic_fmt);
 521             break;
 522         }
 523         case AV_CODEC_ID_H263:
 524         case AV_CODEC_ID_H263P:
 525             /* a=framesize is required by 3GPP TS 26.234 (PSS). It
 526              * actually specifies the maximum video size, but we only know
 527              * the current size. This is required for playback on Android
 528              * stagefright and on Samsung bada. */
 529             if (!fmt || !fmt->oformat->priv_class ||
 530                 !av_opt_flag_is_set(fmt->priv_data, "rtpflags", "rfc2190") ||
 531                 p->codec_id == AV_CODEC_ID_H263P)
 532             av_strlcatf(buff, size, "a=rtpmap:%d H263-2000/90000\r\n"
 533                                     "a=framesize:%d %d-%d\r\n",
 534                                     payload_type,
 535                                     payload_type, p->width, p->height);
 536             break;
 537         case AV_CODEC_ID_HEVC:
 538             if (p->extradata_size)
 539                 config = extradata2psets_hevc(p);
 540             av_strlcatf(buff, size, "a=rtpmap:%d H265/90000\r\n", payload_type);
 541             if (config)
 542                 av_strlcatf(buff, size, "a=fmtp:%d %s\r\n",
 543                                          payload_type, config);
 544             break;
 545         case AV_CODEC_ID_MPEG4:
 546             if (p->extradata_size) {
 547                 config = extradata2config(fmt, p);
 548             }
 549             av_strlcatf(buff, size, "a=rtpmap:%d MP4V-ES/90000\r\n"
 550                                     "a=fmtp:%d profile-level-id=1%s\r\n",
 551                                      payload_type,
 552                                      payload_type, config ? config : "");
 553             break;
 554         case AV_CODEC_ID_AAC:
 555             if (fmt && fmt->oformat && fmt->oformat->priv_class &&
 556                 av_opt_flag_is_set(fmt->priv_data, "rtpflags", "latm")) {
 557                 config = latm_context2config(fmt, p);
 558                 if (!config)
 559                     return NULL;
 560                 av_strlcatf(buff, size, "a=rtpmap:%d MP4A-LATM/%d/%d\r\n"
 561                                         "a=fmtp:%d profile-level-id=%d;cpresent=0;config=%s\r\n",
 562                                          payload_type, p->sample_rate, p->channels,
 563                                          payload_type, latm_context2profilelevel(p), config);
 564             } else {
 565                 if (p->extradata_size) {
 566                     config = extradata2config(fmt, p);
 567                 } else {
 568                     /* FIXME: maybe we can forge config information based on the
 569                      *        codec parameters...
 570                      */
 571                     av_log(fmt, AV_LOG_ERROR, "AAC with no global headers is currently not supported.\n");
 572                     return NULL;
 573                 }
 574                 if (!config) {
 575                     return NULL;
 576                 }
 577                 av_strlcatf(buff, size, "a=rtpmap:%d MPEG4-GENERIC/%d/%d\r\n"
 578                                         "a=fmtp:%d profile-level-id=1;"
 579                                         "mode=AAC-hbr;sizelength=13;indexlength=3;"
 580                                         "indexdeltalength=3%s\r\n",
 581                                          payload_type, p->sample_rate, p->channels,
 582                                          payload_type, config);
 583             }
 584             break;
 585         case AV_CODEC_ID_PCM_S16BE:
 586             if (payload_type >= RTP_PT_PRIVATE)
 587                 av_strlcatf(buff, size, "a=rtpmap:%d L16/%d/%d\r\n",
 588                                          payload_type,
 589                                          p->sample_rate, p->channels);
 590             break;
 591         case AV_CODEC_ID_PCM_S24BE:
 592             if (payload_type >= RTP_PT_PRIVATE)
 593                 av_strlcatf(buff, size, "a=rtpmap:%d L24/%d/%d\r\n",
 594                                          payload_type,
 595                                          p->sample_rate, p->channels);
 596             break;
 597         case AV_CODEC_ID_PCM_MULAW:
 598             if (payload_type >= RTP_PT_PRIVATE)
 599                 av_strlcatf(buff, size, "a=rtpmap:%d PCMU/%d/%d\r\n",
 600                                          payload_type,
 601                                          p->sample_rate, p->channels);
 602             break;
 603         case AV_CODEC_ID_PCM_ALAW:
 604             if (payload_type >= RTP_PT_PRIVATE)
 605                 av_strlcatf(buff, size, "a=rtpmap:%d PCMA/%d/%d\r\n",
 606                                          payload_type,
 607                                          p->sample_rate, p->channels);
 608             break;
 609         case AV_CODEC_ID_AMR_NB:
 610             av_strlcatf(buff, size, "a=rtpmap:%d AMR/%d/%d\r\n"
 611                                     "a=fmtp:%d octet-align=1\r\n",
 612                                      payload_type, p->sample_rate, p->channels,
 613                                      payload_type);
 614             break;
 615         case AV_CODEC_ID_AMR_WB:
 616             av_strlcatf(buff, size, "a=rtpmap:%d AMR-WB/%d/%d\r\n"
 617                                     "a=fmtp:%d octet-align=1\r\n",
 618                                      payload_type, p->sample_rate, p->channels,
 619                                      payload_type);
 620             break;
 621         case AV_CODEC_ID_VORBIS:
 622             if (p->extradata_size)
 623                 config = xiph_extradata2config(fmt, p);
 624             else
 625                 av_log(fmt, AV_LOG_ERROR, "Vorbis configuration info missing\n");
 626             if (!config)
 627                 return NULL;
 628
 629             av_strlcatf(buff, size, "a=rtpmap:%d vorbis/%d/%d\r\n"
 630                                     "a=fmtp:%d configuration=%s\r\n",
 631                                     payload_type, p->sample_rate, p->channels,
 632                                     payload_type, config);
 633             break;
 634         case AV_CODEC_ID_THEORA: {
 635             const char *pix_fmt;
 636             switch (p->format) {
 637             case AV_PIX_FMT_YUV420P:
 638                 pix_fmt = "YCbCr-4:2:0";
 639                 break;
 640             case AV_PIX_FMT_YUV422P:
 641                 pix_fmt = "YCbCr-4:2:2";
 642                 break;
 643             case AV_PIX_FMT_YUV444P:
 644                 pix_fmt = "YCbCr-4:4:4";
 645                 break;
 646             default:
 647                 av_log(fmt, AV_LOG_ERROR, "Unsupported pixel format.\n");
 648                 return NULL;
 649             }
 650
 651             if (p->extradata_size)
 652                 config = xiph_extradata2config(fmt, p);
 653             else
 654                 av_log(fmt, AV_LOG_ERROR, "Theora configuration info missing\n");
 655             if (!config)
 656                 return NULL;
 657
 658             av_strlcatf(buff, size, "a=rtpmap:%d theora/90000\r\n"
 659                                     "a=fmtp:%d delivery-method=inline; "
 660                                     "width=%d; height=%d; sampling=%s; "
 661                                     "configuration=%s\r\n",
 662                                     payload_type, payload_type,
 663                                     p->width, p->height, pix_fmt, config);
 664             break;
 665         }
 666         case AV_CODEC_ID_VP8:
 667             av_strlcatf(buff, size, "a=rtpmap:%d VP8/90000\r\n",
 668                                      payload_type);
 669             break;
 670         case AV_CODEC_ID_VP9:
 671             av_strlcatf(buff, size, "a=rtpmap:%d VP9/90000\r\n",
 672                                      payload_type);
 673             break;
 674         case AV_CODEC_ID_MJPEG:
 675             if (payload_type >= RTP_PT_PRIVATE)
 676                 av_strlcatf(buff, size, "a=rtpmap:%d JPEG/90000\r\n",
 677                                          payload_type);
 678             break;
 679         case AV_CODEC_ID_ADPCM_G722:
 680             if (payload_type >= RTP_PT_PRIVATE)
 681                 av_strlcatf(buff, size, "a=rtpmap:%d G722/%d/%d\r\n",
 682                                          payload_type,
 683                                          8000, p->channels);
 684             break;
 685         case AV_CODEC_ID_ADPCM_G726: {
 686             if (payload_type >= RTP_PT_PRIVATE)
 687                 av_strlcatf(buff, size, "a=rtpmap:%d AAL2-G726-%d/%d\r\n",
 688                                          payload_type,
 689                                          p->bits_per_coded_sample*8,
 690                                          p->sample_rate);
 691             break;
 692         }
 693         case AV_CODEC_ID_ADPCM_G726LE: {
 694             if (payload_type >= RTP_PT_PRIVATE)
 695                 av_strlcatf(buff, size, "a=rtpmap:%d G726-%d/%d\r\n",
 696                                          payload_type,
 697                                          p->bits_per_coded_sample*8,
 698                                          p->sample_rate);
 699             break;
 700         }
 701         case AV_CODEC_ID_ILBC:
 702             av_strlcatf(buff, size, "a=rtpmap:%d iLBC/%d\r\n"
 703                                     "a=fmtp:%d mode=%d\r\n",
 704                                      payload_type, p->sample_rate,
 705                                      payload_type, p->block_align == 38 ? 20 : 30);
 706             break;
 707         case AV_CODEC_ID_SPEEX:
 708             av_strlcatf(buff, size, "a=rtpmap:%d speex/%d\r\n",
 709                                      payload_type, p->sample_rate);
 710             if (st->codec) {
 711                 const char *mode;
 712                 uint64_t vad_option;
 713
 714                 if (st->codec->flags & AV_CODEC_FLAG_QSCALE)
 715                       mode = "on";
 716                 else if (!av_opt_get_int(st->codec, "vad", AV_OPT_FLAG_ENCODING_PARAM, &vad_option) && vad_option)
 717                       mode = "vad";
 718                 else
 719                       mode = "off";
 720
 721                 av_strlcatf(buff, size, "a=fmtp:%d vbr=%s\r\n",
 722                                         payload_type, mode);
 723             }
 724             break;
 725         case AV_CODEC_ID_OPUS:
 726             /* The opus RTP draft says that all opus streams MUST be declared
 727                as stereo, to avoid negotiation failures. The actual number of
 728                channels can change on a packet-by-packet basis. The number of
 729                channels a receiver prefers to receive or a sender plans to send
 730                can be declared via fmtp parameters (both default to mono), but
 731                receivers MUST be able to receive and process stereo packets. */
 732             av_strlcatf(buff, size, "a=rtpmap:%d opus/48000/2\r\n",
 733                                      payload_type);
 734             if (p->channels == 2) {
 735                 av_strlcatf(buff, size, "a=fmtp:%d sprop-stereo=1\r\n",
 736                                          payload_type);
 737             }
 738             break;
 739         default:
 740             /* Nothing special to do here... */
 741             break;
 742     }
 743
 744     av_free(config);
 745
 746     return buff;
 747 }
 748
 749 void ff_sdp_write_media(char *buff, int size, AVStream *st, int idx,
 750                         const char *dest_addr, const char *dest_type,
 751                         int port, int ttl, AVFormatContext *fmt)
 752 {
 753     AVCodecParameters *p = st->codecpar;
 754     const char *type;
 755     int payload_type;
 756
 757     payload_type = ff_rtp_get_payload_type(fmt, st->codecpar, idx);
 758
 759     switch (p->codec_type) {
 760         case AVMEDIA_TYPE_VIDEO   : type = "video"      ; break;
 761         case AVMEDIA_TYPE_AUDIO   : type = "audio"      ; break;
 762         case AVMEDIA_TYPE_SUBTITLE: type = "text"       ; break;
 763         default                 : type = "application"; break;
 764     }
 765
 766     av_strlcatf(buff, size, "m=%s %d RTP/AVP %d\r\n", type, port, payload_type);
 767     sdp_write_address(buff, size, dest_addr, dest_type, ttl);
 768     if (p->bit_rate) {
 769         av_strlcatf(buff, size, "b=AS:%"PRId64"\r\n", p->bit_rate / 1000);
 770     }
 771
 772     sdp_write_media_attributes(buff, size, st, payload_type, fmt);
 773 }
 774
 775 int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size)
 776 {
 777     AVDictionaryEntry *title = av_dict_get(ac[0]->metadata, "title", NULL, 0);
 778     struct sdp_session_level s = { 0 };
 779     int i, j, port, ttl, is_multicast, index = 0;
 780     char dst[32], dst_type[5];
 781
 782     memset(buf, 0, size);
 783     s.user = "-";
 784     s.src_addr = "127.0.0.1";    /* FIXME: Properly set this */
 785     s.src_type = "IP4";
 786     s.name = title ? title->value : "No Name";
 787
 788     port = 0;
 789     ttl = 0;
 790     if (n_files == 1) {
 791         port = sdp_get_address(dst, sizeof(dst), &ttl, ac[0]->url ? ac[0]->url : "");
 792         is_multicast = resolve_destination(dst, sizeof(dst), dst_type,
 793                                            sizeof(dst_type));
 794         if (!is_multicast)
 795             ttl = 0;
 796         if (dst[0]) {
 797             s.dst_addr = dst;
 798             s.dst_type = dst_type;
 799             s.ttl = ttl;
 800             if (!strcmp(dst_type, "IP6")) {
 801                 s.src_addr = "::1";
 802                 s.src_type = "IP6";
 803             }
 804         }
 805     }
 806     sdp_write_header(buf, size, &s);
 807
 808     dst[0] = 0;
 809     for (i = 0; i < n_files; i++) {
 810         if (n_files != 1) {
 811             port = sdp_get_address(dst, sizeof(dst), &ttl, ac[i]->url ? ac[i]->url : "");
 812             is_multicast = resolve_destination(dst, sizeof(dst), dst_type,
 813                                                sizeof(dst_type));
 814             if (!is_multicast)
 815                 ttl = 0;
 816         }
 817         for (j = 0; j < ac[i]->nb_streams; j++) {
 818             ff_sdp_write_media(buf, size, ac[i]->streams[j], index++,
 819                                dst[0] ? dst : NULL, dst_type,
 820                                (port > 0) ? port + j * 2 : 0,
 821                                ttl, ac[i]);
 822             if (port <= 0) {
 823                 av_strlcatf(buf, size,
 824                                    "a=control:streamid=%d\r\n", i + j);
 825             }
 826             if (ac[i]->pb && ac[i]->pb->av_class) {
 827                 uint8_t *crypto_suite = NULL, *crypto_params = NULL;
 828                 av_opt_get(ac[i]->pb, "srtp_out_suite",  AV_OPT_SEARCH_CHILDREN,
 829                            &crypto_suite);
 830                 av_opt_get(ac[i]->pb, "srtp_out_params", AV_OPT_SEARCH_CHILDREN,
 831                            &crypto_params);
 832                 if (crypto_suite && crypto_suite[0])
 833                     av_strlcatf(buf, size,
 834                                 "a=crypto:1 %s inline:%s\r\n",
 835                                 crypto_suite, crypto_params);
 836                 av_free(crypto_suite);
 837                 av_free(crypto_params);
 838             }
 839         }
 840     }
 841
 842     return 0;
 843 }
 844 #else
 845 int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size)
 846 {
 847     return AVERROR(ENOSYS);
 848 }
 849
 850 void ff_sdp_write_media(char *buff, int size, AVStream *st, int idx,
 851                         const char *dest_addr, const char *dest_type,
 852                         int port, int ttl, AVFormatContext *fmt)
 853 {
 854 }
 855 #endif