00001 /* 00002 * copyright (c) 2007 Luca Abeni 00003 * 00004 * This file is part of FFmpeg. 00005 * 00006 * FFmpeg is free software; you can redistribute it and/or 00007 * modify it under the terms of the GNU Lesser General Public 00008 * License as published by the Free Software Foundation; either 00009 * version 2.1 of the License, or (at your option) any later version. 00010 * 00011 * FFmpeg is distributed in the hope that it will be useful, 00012 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00014 * Lesser General Public License for more details. 00015 * 00016 * You should have received a copy of the GNU Lesser General Public 00017 * License along with FFmpeg; if not, write to the Free Software 00018 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00019 */ 00020 00021 #include <string.h> 00022 #include "libavutil/avstring.h" 00023 #include "libavutil/base64.h" 00024 #include "libavutil/dict.h" 00025 #include "libavutil/parseutils.h" 00026 #include "libavutil/opt.h" 00027 #include "libavcodec/xiph.h" 00028 #include "libavcodec/mpeg4audio.h" 00029 #include "avformat.h" 00030 #include "internal.h" 00031 #include "avc.h" 00032 #include "rtp.h" 00033 #if CONFIG_NETWORK 00034 #include "network.h" 00035 #endif 00036 00037 #if CONFIG_RTP_MUXER 00038 #define MAX_EXTRADATA_SIZE ((INT_MAX - 10) / 2) 00039 00040 struct sdp_session_level { 00041 int sdp_version; 00042 int id; 00043 int version; 00044 int start_time; 00046 int end_time; 00048 int ttl; 00049 const char *user; 00050 const char *src_addr; 00051 const char *src_type; 00052 const char *dst_addr; 00053 const char *dst_type; 00054 const char *name; 00055 }; 00056 00057 static void sdp_write_address(char *buff, int size, const char *dest_addr, 00058 const char *dest_type, int ttl) 00059 { 00060 if (dest_addr) { 00061 if (!dest_type) 00062 dest_type = "IP4"; 00063 if (ttl > 0 && !strcmp(dest_type, "IP4")) { 00064 /* The TTL should only be specified for IPv4 multicast addresses, 00065 * not for IPv6. */ 00066 av_strlcatf(buff, size, "c=IN %s %s/%d\r\n", dest_type, dest_addr, ttl); 00067 } else { 00068 av_strlcatf(buff, size, "c=IN %s %s\r\n", dest_type, dest_addr); 00069 } 00070 } 00071 } 00072 00073 static void sdp_write_header(char *buff, int size, struct sdp_session_level *s) 00074 { 00075 av_strlcatf(buff, size, "v=%d\r\n" 00076 "o=- %d %d IN %s %s\r\n" 00077 "s=%s\r\n", 00078 s->sdp_version, 00079 s->id, s->version, s->src_type, s->src_addr, 00080 s->name); 00081 sdp_write_address(buff, size, s->dst_addr, s->dst_type, s->ttl); 00082 av_strlcatf(buff, size, "t=%d %d\r\n" 00083 "a=tool:libavformat " AV_STRINGIFY(LIBAVFORMAT_VERSION) "\r\n", 00084 s->start_time, s->end_time); 00085 } 00086 00087 #if CONFIG_NETWORK 00088 static int resolve_destination(char *dest_addr, int size, char *type, 00089 int type_size) 00090 { 00091 struct addrinfo hints, *ai; 00092 int is_multicast; 00093 00094 av_strlcpy(type, "IP4", type_size); 00095 if (!dest_addr[0]) 00096 return 0; 00097 00098 /* Resolve the destination, since it must be written 00099 * as a numeric IP address in the SDP. */ 00100 00101 memset(&hints, 0, sizeof(hints)); 00102 if (getaddrinfo(dest_addr, NULL, &hints, &ai)) 00103 return 0; 00104 getnameinfo(ai->ai_addr, ai->ai_addrlen, dest_addr, size, 00105 NULL, 0, NI_NUMERICHOST); 00106 #ifdef AF_INET6 00107 if (ai->ai_family == AF_INET6) 00108 av_strlcpy(type, "IP6", type_size); 00109 #endif 00110 is_multicast = ff_is_multicast_address(ai->ai_addr); 00111 freeaddrinfo(ai); 00112 return is_multicast; 00113 } 00114 #else 00115 static int resolve_destination(char *dest_addr, int size, char *type, 00116 int type_size) 00117 { 00118 return 0; 00119 } 00120 #endif 00121 00122 static int sdp_get_address(char *dest_addr, int size, int *ttl, const char *url) 00123 { 00124 int port; 00125 const char *p; 00126 char proto[32]; 00127 00128 av_url_split(proto, sizeof(proto), NULL, 0, dest_addr, size, &port, NULL, 0, url); 00129 00130 *ttl = 0; 00131 00132 if (strcmp(proto, "rtp")) { 00133 /* The url isn't for the actual rtp sessions, 00134 * don't parse out anything else than the destination. 00135 */ 00136 return 0; 00137 } 00138 00139 p = strchr(url, '?'); 00140 if (p) { 00141 char buff[64]; 00142 00143 if (av_find_info_tag(buff, sizeof(buff), "ttl", p)) { 00144 *ttl = strtol(buff, NULL, 10); 00145 } else { 00146 *ttl = 5; 00147 } 00148 } 00149 00150 return port; 00151 } 00152 00153 #define MAX_PSET_SIZE 1024 00154 static char *extradata2psets(AVCodecContext *c) 00155 { 00156 char *psets, *p; 00157 const uint8_t *r; 00158 const char *pset_string = "; sprop-parameter-sets="; 00159 uint8_t *orig_extradata = NULL; 00160 int orig_extradata_size = 0; 00161 00162 if (c->extradata_size > MAX_EXTRADATA_SIZE) { 00163 av_log(c, AV_LOG_ERROR, "Too much extradata!\n"); 00164 00165 return NULL; 00166 } 00167 if (c->extradata[0] == 1) { 00168 uint8_t *dummy_p; 00169 int dummy_int; 00170 AVBitStreamFilterContext *bsfc= av_bitstream_filter_init("h264_mp4toannexb"); 00171 00172 if (!bsfc) { 00173 av_log(c, AV_LOG_ERROR, "Cannot open the h264_mp4toannexb BSF!\n"); 00174 00175 return NULL; 00176 } 00177 00178 orig_extradata_size = c->extradata_size; 00179 orig_extradata = av_mallocz(orig_extradata_size + 00180 FF_INPUT_BUFFER_PADDING_SIZE); 00181 if (!orig_extradata) { 00182 av_bitstream_filter_close(bsfc); 00183 return NULL; 00184 } 00185 memcpy(orig_extradata, c->extradata, orig_extradata_size); 00186 av_bitstream_filter_filter(bsfc, c, NULL, &dummy_p, &dummy_int, NULL, 0, 0); 00187 av_bitstream_filter_close(bsfc); 00188 } 00189 00190 psets = av_mallocz(MAX_PSET_SIZE); 00191 if (psets == NULL) { 00192 av_log(c, AV_LOG_ERROR, "Cannot allocate memory for the parameter sets.\n"); 00193 av_free(orig_extradata); 00194 return NULL; 00195 } 00196 memcpy(psets, pset_string, strlen(pset_string)); 00197 p = psets + strlen(pset_string); 00198 r = ff_avc_find_startcode(c->extradata, c->extradata + c->extradata_size); 00199 while (r < c->extradata + c->extradata_size) { 00200 const uint8_t *r1; 00201 uint8_t nal_type; 00202 00203 while (!*(r++)); 00204 nal_type = *r & 0x1f; 00205 r1 = ff_avc_find_startcode(r, c->extradata + c->extradata_size); 00206 if (nal_type != 7 && nal_type != 8) { /* Only output SPS and PPS */ 00207 r = r1; 00208 continue; 00209 } 00210 if (p != (psets + strlen(pset_string))) { 00211 *p = ','; 00212 p++; 00213 } 00214 if (av_base64_encode(p, MAX_PSET_SIZE - (p - psets), r, r1 - r) == NULL) { 00215 av_log(c, AV_LOG_ERROR, "Cannot Base64-encode %td %td!\n", MAX_PSET_SIZE - (p - psets), r1 - r); 00216 av_free(psets); 00217 00218 return NULL; 00219 } 00220 p += strlen(p); 00221 r = r1; 00222 } 00223 if (orig_extradata) { 00224 av_free(c->extradata); 00225 c->extradata = orig_extradata; 00226 c->extradata_size = orig_extradata_size; 00227 } 00228 00229 return psets; 00230 } 00231 00232 static char *extradata2config(AVCodecContext *c) 00233 { 00234 char *config; 00235 00236 if (c->extradata_size > MAX_EXTRADATA_SIZE) { 00237 av_log(c, AV_LOG_ERROR, "Too much extradata!\n"); 00238 00239 return NULL; 00240 } 00241 config = av_malloc(10 + c->extradata_size * 2); 00242 if (config == NULL) { 00243 av_log(c, AV_LOG_ERROR, "Cannot allocate memory for the config info.\n"); 00244 return NULL; 00245 } 00246 memcpy(config, "; config=", 9); 00247 ff_data_to_hex(config + 9, c->extradata, c->extradata_size, 0); 00248 config[9 + c->extradata_size * 2] = 0; 00249 00250 return config; 00251 } 00252 00253 static char *xiph_extradata2config(AVCodecContext *c) 00254 { 00255 char *config, *encoded_config; 00256 uint8_t *header_start[3]; 00257 int headers_len, header_len[3], config_len; 00258 int first_header_size; 00259 00260 switch (c->codec_id) { 00261 case CODEC_ID_THEORA: 00262 first_header_size = 42; 00263 break; 00264 case CODEC_ID_VORBIS: 00265 first_header_size = 30; 00266 break; 00267 default: 00268 av_log(c, AV_LOG_ERROR, "Unsupported Xiph codec ID\n"); 00269 return NULL; 00270 } 00271 00272 if (avpriv_split_xiph_headers(c->extradata, c->extradata_size, 00273 first_header_size, header_start, 00274 header_len) < 0) { 00275 av_log(c, AV_LOG_ERROR, "Extradata corrupt.\n"); 00276 return NULL; 00277 } 00278 00279 headers_len = header_len[0] + header_len[2]; 00280 config_len = 4 + // count 00281 3 + // ident 00282 2 + // packet size 00283 1 + // header count 00284 2 + // header size 00285 headers_len; // and the rest 00286 00287 config = av_malloc(config_len); 00288 if (!config) 00289 goto xiph_fail; 00290 00291 encoded_config = av_malloc(AV_BASE64_SIZE(config_len)); 00292 if (!encoded_config) { 00293 av_free(config); 00294 goto xiph_fail; 00295 } 00296 00297 config[0] = config[1] = config[2] = 0; 00298 config[3] = 1; 00299 config[4] = (RTP_XIPH_IDENT >> 16) & 0xff; 00300 config[5] = (RTP_XIPH_IDENT >> 8) & 0xff; 00301 config[6] = (RTP_XIPH_IDENT ) & 0xff; 00302 config[7] = (headers_len >> 8) & 0xff; 00303 config[8] = headers_len & 0xff; 00304 config[9] = 2; 00305 config[10] = header_len[0]; 00306 config[11] = 0; // size of comment header; nonexistent 00307 memcpy(config + 12, header_start[0], header_len[0]); 00308 memcpy(config + 12 + header_len[0], header_start[2], header_len[2]); 00309 00310 av_base64_encode(encoded_config, AV_BASE64_SIZE(config_len), 00311 config, config_len); 00312 av_free(config); 00313 00314 return encoded_config; 00315 00316 xiph_fail: 00317 av_log(c, AV_LOG_ERROR, 00318 "Not enough memory for configuration string\n"); 00319 return NULL; 00320 } 00321 00322 static int latm_context2profilelevel(AVCodecContext *c) 00323 { 00324 /* MP4A-LATM 00325 * The RTP payload format specification is described in RFC 3016 00326 * The encoding specifications are provided in ISO/IEC 14496-3 */ 00327 00328 int profile_level = 0x2B; 00329 00330 /* TODO: AAC Profile only supports AAC LC Object Type. 00331 * Different Object Types should implement different Profile Levels */ 00332 00333 if (c->sample_rate <= 24000) { 00334 if (c->channels <= 2) 00335 profile_level = 0x28; // AAC Profile, Level 1 00336 } else if (c->sample_rate <= 48000) { 00337 if (c->channels <= 2) { 00338 profile_level = 0x29; // AAC Profile, Level 2 00339 } else if (c->channels <= 5) { 00340 profile_level = 0x2A; // AAC Profile, Level 4 00341 } 00342 } else if (c->sample_rate <= 96000) { 00343 if (c->channels <= 5) { 00344 profile_level = 0x2B; // AAC Profile, Level 5 00345 } 00346 } 00347 00348 return profile_level; 00349 } 00350 00351 static char *latm_context2config(AVCodecContext *c) 00352 { 00353 /* MP4A-LATM 00354 * The RTP payload format specification is described in RFC 3016 00355 * The encoding specifications are provided in ISO/IEC 14496-3 */ 00356 00357 uint8_t config_byte[6]; 00358 int rate_index; 00359 char *config; 00360 00361 for (rate_index = 0; rate_index < 16; rate_index++) 00362 if (avpriv_mpeg4audio_sample_rates[rate_index] == c->sample_rate) 00363 break; 00364 if (rate_index == 16) { 00365 av_log(c, AV_LOG_ERROR, "Unsupported sample rate\n"); 00366 return NULL; 00367 } 00368 00369 config_byte[0] = 0x40; 00370 config_byte[1] = 0; 00371 config_byte[2] = 0x20 | rate_index; 00372 config_byte[3] = c->channels << 4; 00373 config_byte[4] = 0x3f; 00374 config_byte[5] = 0xc0; 00375 00376 config = av_malloc(6*2+1); 00377 if (!config) { 00378 av_log(c, AV_LOG_ERROR, "Cannot allocate memory for the config info.\n"); 00379 return NULL; 00380 } 00381 ff_data_to_hex(config, config_byte, 6, 1); 00382 config[12] = 0; 00383 00384 return config; 00385 } 00386 00387 static char *sdp_write_media_attributes(char *buff, int size, AVCodecContext *c, int payload_type, AVFormatContext *fmt) 00388 { 00389 char *config = NULL; 00390 00391 switch (c->codec_id) { 00392 case CODEC_ID_H264: 00393 if (c->extradata_size) { 00394 config = extradata2psets(c); 00395 } 00396 av_strlcatf(buff, size, "a=rtpmap:%d H264/90000\r\n" 00397 "a=fmtp:%d packetization-mode=1%s\r\n", 00398 payload_type, 00399 payload_type, config ? config : ""); 00400 break; 00401 case CODEC_ID_H263: 00402 case CODEC_ID_H263P: 00403 /* a=framesize is required by 3GPP TS 26.234 (PSS). It 00404 * actually specifies the maximum video size, but we only know 00405 * the current size. This is required for playback on Android 00406 * stagefright and on Samsung bada. */ 00407 av_strlcatf(buff, size, "a=rtpmap:%d H263-2000/90000\r\n" 00408 "a=framesize:%d %d-%d\r\n", 00409 payload_type, 00410 payload_type, c->width, c->height); 00411 break; 00412 case CODEC_ID_MPEG4: 00413 if (c->extradata_size) { 00414 config = extradata2config(c); 00415 } 00416 av_strlcatf(buff, size, "a=rtpmap:%d MP4V-ES/90000\r\n" 00417 "a=fmtp:%d profile-level-id=1%s\r\n", 00418 payload_type, 00419 payload_type, config ? config : ""); 00420 break; 00421 case CODEC_ID_AAC: 00422 if (fmt && fmt->oformat && fmt->oformat->priv_class && 00423 av_opt_flag_is_set(fmt->priv_data, "rtpflags", "latm")) { 00424 config = latm_context2config(c); 00425 if (!config) 00426 return NULL; 00427 av_strlcatf(buff, size, "a=rtpmap:%d MP4A-LATM/%d/%d\r\n" 00428 "a=fmtp:%d profile-level-id=%d;cpresent=0;config=%s\r\n", 00429 payload_type, c->sample_rate, c->channels, 00430 payload_type, latm_context2profilelevel(c), config); 00431 } else { 00432 if (c->extradata_size) { 00433 config = extradata2config(c); 00434 } else { 00435 /* FIXME: maybe we can forge config information based on the 00436 * codec parameters... 00437 */ 00438 av_log(c, AV_LOG_ERROR, "AAC with no global headers is currently not supported.\n"); 00439 return NULL; 00440 } 00441 if (config == NULL) { 00442 return NULL; 00443 } 00444 av_strlcatf(buff, size, "a=rtpmap:%d MPEG4-GENERIC/%d/%d\r\n" 00445 "a=fmtp:%d profile-level-id=1;" 00446 "mode=AAC-hbr;sizelength=13;indexlength=3;" 00447 "indexdeltalength=3%s\r\n", 00448 payload_type, c->sample_rate, c->channels, 00449 payload_type, config); 00450 } 00451 break; 00452 case CODEC_ID_PCM_S16BE: 00453 if (payload_type >= RTP_PT_PRIVATE) 00454 av_strlcatf(buff, size, "a=rtpmap:%d L16/%d/%d\r\n", 00455 payload_type, 00456 c->sample_rate, c->channels); 00457 break; 00458 case CODEC_ID_PCM_MULAW: 00459 if (payload_type >= RTP_PT_PRIVATE) 00460 av_strlcatf(buff, size, "a=rtpmap:%d PCMU/%d/%d\r\n", 00461 payload_type, 00462 c->sample_rate, c->channels); 00463 break; 00464 case CODEC_ID_PCM_ALAW: 00465 if (payload_type >= RTP_PT_PRIVATE) 00466 av_strlcatf(buff, size, "a=rtpmap:%d PCMA/%d/%d\r\n", 00467 payload_type, 00468 c->sample_rate, c->channels); 00469 break; 00470 case CODEC_ID_AMR_NB: 00471 av_strlcatf(buff, size, "a=rtpmap:%d AMR/%d/%d\r\n" 00472 "a=fmtp:%d octet-align=1\r\n", 00473 payload_type, c->sample_rate, c->channels, 00474 payload_type); 00475 break; 00476 case CODEC_ID_AMR_WB: 00477 av_strlcatf(buff, size, "a=rtpmap:%d AMR-WB/%d/%d\r\n" 00478 "a=fmtp:%d octet-align=1\r\n", 00479 payload_type, c->sample_rate, c->channels, 00480 payload_type); 00481 break; 00482 case CODEC_ID_VORBIS: 00483 if (c->extradata_size) 00484 config = xiph_extradata2config(c); 00485 else 00486 av_log(c, AV_LOG_ERROR, "Vorbis configuration info missing\n"); 00487 if (!config) 00488 return NULL; 00489 00490 av_strlcatf(buff, size, "a=rtpmap:%d vorbis/%d/%d\r\n" 00491 "a=fmtp:%d configuration=%s\r\n", 00492 payload_type, c->sample_rate, c->channels, 00493 payload_type, config); 00494 break; 00495 case CODEC_ID_THEORA: { 00496 const char *pix_fmt; 00497 if (c->extradata_size) 00498 config = xiph_extradata2config(c); 00499 else 00500 av_log(c, AV_LOG_ERROR, "Theora configuation info missing\n"); 00501 if (!config) 00502 return NULL; 00503 00504 switch (c->pix_fmt) { 00505 case PIX_FMT_YUV420P: 00506 pix_fmt = "YCbCr-4:2:0"; 00507 break; 00508 case PIX_FMT_YUV422P: 00509 pix_fmt = "YCbCr-4:2:2"; 00510 break; 00511 case PIX_FMT_YUV444P: 00512 pix_fmt = "YCbCr-4:4:4"; 00513 break; 00514 default: 00515 av_log(c, AV_LOG_ERROR, "Unsupported pixel format.\n"); 00516 return NULL; 00517 } 00518 00519 av_strlcatf(buff, size, "a=rtpmap:%d theora/90000\r\n" 00520 "a=fmtp:%d delivery-method=inline; " 00521 "width=%d; height=%d; sampling=%s; " 00522 "configuration=%s\r\n", 00523 payload_type, payload_type, 00524 c->width, c->height, pix_fmt, config); 00525 break; 00526 } 00527 case CODEC_ID_VP8: 00528 av_strlcatf(buff, size, "a=rtpmap:%d VP8/90000\r\n", 00529 payload_type); 00530 break; 00531 case CODEC_ID_ADPCM_G722: 00532 if (payload_type >= RTP_PT_PRIVATE) 00533 av_strlcatf(buff, size, "a=rtpmap:%d G722/%d/%d\r\n", 00534 payload_type, 00535 8000, c->channels); 00536 break; 00537 case CODEC_ID_ADPCM_G726: { 00538 if (payload_type >= RTP_PT_PRIVATE) 00539 av_strlcatf(buff, size, "a=rtpmap:%d G726-%d/%d\r\n", 00540 payload_type, 00541 c->bits_per_coded_sample*8, 00542 c->sample_rate); 00543 break; 00544 } 00545 default: 00546 /* Nothing special to do here... */ 00547 break; 00548 } 00549 00550 av_free(config); 00551 00552 return buff; 00553 } 00554 00555 void ff_sdp_write_media(char *buff, int size, AVCodecContext *c, const char *dest_addr, const char *dest_type, int port, int ttl, AVFormatContext *fmt) 00556 { 00557 const char *type; 00558 int payload_type; 00559 00560 payload_type = ff_rtp_get_payload_type(fmt, c); 00561 00562 switch (c->codec_type) { 00563 case AVMEDIA_TYPE_VIDEO : type = "video" ; break; 00564 case AVMEDIA_TYPE_AUDIO : type = "audio" ; break; 00565 case AVMEDIA_TYPE_SUBTITLE: type = "text" ; break; 00566 default : type = "application"; break; 00567 } 00568 00569 av_strlcatf(buff, size, "m=%s %d RTP/AVP %d\r\n", type, port, payload_type); 00570 sdp_write_address(buff, size, dest_addr, dest_type, ttl); 00571 if (c->bit_rate) { 00572 av_strlcatf(buff, size, "b=AS:%d\r\n", c->bit_rate / 1000); 00573 } 00574 00575 sdp_write_media_attributes(buff, size, c, payload_type, fmt); 00576 } 00577 00578 int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size) 00579 { 00580 AVDictionaryEntry *title = av_dict_get(ac[0]->metadata, "title", NULL, 0); 00581 struct sdp_session_level s; 00582 int i, j, port, ttl, is_multicast; 00583 char dst[32], dst_type[5]; 00584 00585 memset(buf, 0, size); 00586 memset(&s, 0, sizeof(struct sdp_session_level)); 00587 s.user = "-"; 00588 s.src_addr = "127.0.0.1"; /* FIXME: Properly set this */ 00589 s.src_type = "IP4"; 00590 s.name = title ? title->value : "No Name"; 00591 00592 port = 0; 00593 ttl = 0; 00594 if (n_files == 1) { 00595 port = sdp_get_address(dst, sizeof(dst), &ttl, ac[0]->filename); 00596 is_multicast = resolve_destination(dst, sizeof(dst), dst_type, 00597 sizeof(dst_type)); 00598 if (!is_multicast) 00599 ttl = 0; 00600 if (dst[0]) { 00601 s.dst_addr = dst; 00602 s.dst_type = dst_type; 00603 s.ttl = ttl; 00604 if (!strcmp(dst_type, "IP6")) { 00605 s.src_addr = "::1"; 00606 s.src_type = "IP6"; 00607 } 00608 } 00609 } 00610 sdp_write_header(buf, size, &s); 00611 00612 dst[0] = 0; 00613 for (i = 0; i < n_files; i++) { 00614 if (n_files != 1) { 00615 port = sdp_get_address(dst, sizeof(dst), &ttl, ac[i]->filename); 00616 is_multicast = resolve_destination(dst, sizeof(dst), dst_type, 00617 sizeof(dst_type)); 00618 if (!is_multicast) 00619 ttl = 0; 00620 } 00621 for (j = 0; j < ac[i]->nb_streams; j++) { 00622 ff_sdp_write_media(buf, size, 00623 ac[i]->streams[j]->codec, dst[0] ? dst : NULL, 00624 dst_type, (port > 0) ? port + j * 2 : 0, ttl, 00625 ac[i]); 00626 if (port <= 0) { 00627 av_strlcatf(buf, size, 00628 "a=control:streamid=%d\r\n", i + j); 00629 } 00630 } 00631 } 00632 00633 return 0; 00634 } 00635 #else 00636 int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size) 00637 { 00638 return AVERROR(ENOSYS); 00639 } 00640 00641 void ff_sdp_write_media(char *buff, int size, AVCodecContext *c, const char *dest_addr, const char *dest_type, int port, int ttl, AVFormatContext *fmt) 00642 { 00643 } 00644 #endif 00645 00646 #if FF_API_SDP_CREATE 00647 int avf_sdp_create(AVFormatContext *ac[], int n_files, char *buff, int size) 00648 { 00649 return av_sdp_create(ac, n_files, buff, size); 00650 } 00651 #endif