libavformat/rtp_h264.c

   1 /*
   2  * RTP H264 Protocol (RFC3984)
   3  * Copyright (c) 2006 Ryan Martell.
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23 * @file rtp_h264.c
  24  * @brief H.264 / RTP Code (RFC3984)
  25  * @author Ryan Martell <rdm4@martellventures.com>
  26  *
  27  * @note Notes:
  28  * Notes:
  29  * This currently supports packetization mode:
  30  * Single Nal Unit Mode (0), or
  31  * Non-Interleaved Mode (1).  It currently does not support
  32  * Interleaved Mode (2). (This requires implementing STAP-B, MTAP16, MTAP24, FU-B packet types)
  33  *
  34  * @note TODO:
  35  * 1) RTCP sender reports for udp streams are required..
  36  *
  37  */
  38
  39 #include "avformat.h"
  40 #include "mpegts.h"
  41 #include "bitstream.h"
  42
  43 #include <unistd.h>
  44 #include <sys/types.h>
  45 #include <sys/socket.h>
  46 #include <netinet/in.h>
  47 #include <assert.h>
  48 #include <arpa/inet.h>
  49 #include <netdb.h>
  50
  51 #include "rtp_internal.h"
  52 #include "rtp_h264.h"
  53 #include "base64.h"
  54
  55 /**
  56     RTP/H264 specific private data.
  57 */
  58 typedef struct h264_rtp_extra_data {
  59     unsigned long cookie;       ///< sanity check, to make sure we get the pointer we're expecting.
  60
  61     //sdp setup parameters
  62     uint8_t profile_idc;        ///< from the sdp setup parameters.
  63     uint8_t profile_iop;        ///< from the sdp setup parameters.
  64     uint8_t level_idc;          ///< from the sdp setup parameters.
  65     int packetization_mode;     ///< from the sdp setup parameters.
  66 #ifdef DEBUG
  67     int packet_types_received[32];
  68 #endif
  69 } h264_rtp_extra_data;
  70
  71 #define MAGIC_COOKIE (0xdeadbeef)       ///< Cookie for the extradata; to verify we are what we think we are, and that we haven't been freed.
  72 #define DEAD_COOKIE (0xdeaddead)        ///< Cookie for the extradata; once it is freed.
  73
  74 /* ---------------- private code */
  75 static void sdp_parse_fmtp_config_h264(AVStream * stream,
  76                                        h264_rtp_extra_data * h264_data,
  77                                        char *attr, char *value)
  78 {
  79     AVCodecContext *codec = stream->codec;
  80     assert(codec->codec_id == CODEC_ID_H264);
  81     assert(h264_data != NULL);
  82
  83     if (!strcmp(attr, "packetization-mode")) {
  84         av_log(NULL, AV_LOG_DEBUG, "H.264/RTP Packetization Mode: %d\n", atoi(attr));
  85         h264_data->packetization_mode = atoi(attr);
  86         /*
  87            Packetization Mode:
  88            0 or not present: Single NAL mode (Only nals from 1-23 are allowed)
  89            1: Non-interleaved Mode: 1-23, 24 (STAP-A), 28 (FU-A) are allowed.
  90            2: Interleaved Mode: 25 (STAP-B), 26 (MTAP16), 27 (MTAP24), 28 (FU-A), and 29 (FU-B) are allowed.
  91          */
  92         if (h264_data->packetization_mode > 1)
  93             av_log(stream, AV_LOG_ERROR,
  94                    "H.264/RTP Interleaved RTP mode is not supported yet.");
  95     } else if (!strcmp(attr, "profile-level-id")) {
  96         if (strlen(value) == 6) {
  97             char buffer[3];
  98             // 6 characters=3 bytes, in hex.
  99             uint8_t profile_idc;
 100             uint8_t profile_iop;
 101             uint8_t level_idc;
 102
 103             buffer[0] = value[0]; buffer[1] = value[1]; buffer[2] = '\0';
 104             profile_idc = strtol(buffer, NULL, 16);
 105             buffer[0] = value[2]; buffer[1] = value[3];
 106             profile_iop = strtol(buffer, NULL, 16);
 107             buffer[0] = value[4]; buffer[1] = value[5];
 108             level_idc = strtol(buffer, NULL, 16);
 109
 110             // set the parameters...
 111             av_log(NULL, AV_LOG_DEBUG,
 112                    "H.264/RTP Profile IDC: %x Profile IOP: %x Level: %x\n",
 113                    profile_idc, profile_iop, level_idc);
 114             h264_data->profile_idc = profile_idc;
 115             h264_data->profile_iop = profile_iop;
 116             h264_data->level_idc = level_idc;
 117         }
 118     } else  if (!strcmp(attr, "sprop-parameter-sets")) {
 119         uint8_t start_sequence[]= { 0, 0, 1 };
 120         codec->extradata_size= 0;
 121         codec->extradata= NULL;
 122
 123         while (*value) {
 124             char base64packet[1024];
 125             uint8_t decoded_packet[1024];
 126             uint32_t packet_size;
 127             char *dst = base64packet;
 128
 129             while (*value && *value != ','
 130                    && (dst - base64packet) < sizeof(base64packet) - 1) {
 131                 *dst++ = *value++;
 132             }
 133             *dst++ = '\0';
 134
 135             if (*value == ',')
 136                 value++;
 137
 138             packet_size= av_base64_decode(decoded_packet, base64packet, sizeof(decoded_packet));
 139             if (packet_size) {
 140                 uint8_t *dest= av_malloc(packet_size+sizeof(start_sequence)+codec->extradata_size);
 141                 if(dest)
 142                 {
 143                     if(codec->extradata_size)
 144                     {
 145                         // av_realloc?
 146                         memcpy(dest, codec->extradata, codec->extradata_size);
 147                         av_free(codec->extradata);
 148                     }
 149
 150                     memcpy(dest+codec->extradata_size, start_sequence, sizeof(start_sequence));
 151                     memcpy(dest+codec->extradata_size+sizeof(start_sequence), decoded_packet, packet_size);
 152
 153                     codec->extradata= dest;
 154                     codec->extradata_size+= sizeof(start_sequence)+packet_size;
 155                 } else {
 156                     av_log(NULL, AV_LOG_ERROR, "H.264/RTP Unable to allocate memory for extradata!");
 157                 }
 158             }
 159         }
 160         av_log(NULL, AV_LOG_DEBUG, "H.264/RTP Extradata set to %p (size: %d)!", codec->extradata, codec->extradata_size);
 161     }
 162 }
 163
 164 // return 0 on packet, no more left, 1 on packet, 1 on partial packet...
 165 static int h264_handle_packet(RTPDemuxContext * s,
 166                               AVPacket * pkt,
 167                               uint32_t * timestamp,
 168                               const uint8_t * buf,
 169                               int len)
 170 {
 171 //    h264_rtp_extra_data *data = s->dynamic_protocol_context;
 172     uint8_t nal = buf[0];
 173     uint8_t type = (nal & 0x1f);
 174     int result= 0;
 175     uint8_t start_sequence[]= {0, 0, 1};
 176
 177     assert(data);
 178     assert(data->cookie == MAGIC_COOKIE);
 179     assert(buf);
 180
 181     if (type >= 1 && type <= 23)
 182         type = 1;              // simplify the case. (these are all the nal types used internally by the h264 codec)
 183     switch (type) {
 184     case 0:                    // undefined;
 185         result= -1;
 186         break;
 187
 188     case 1:
 189         av_new_packet(pkt, len+sizeof(start_sequence));
 190         memcpy(pkt->data, start_sequence, sizeof(start_sequence));
 191         memcpy(pkt->data+sizeof(start_sequence), buf, len);
 192 #ifdef DEBUG
 193         data->packet_types_received[nal & 0x1f]++;
 194 #endif
 195         break;
 196
 197     case 24:                   // STAP-A (one packet, multiple nals)
 198         // consume the STAP-A NAL
 199         buf++;
 200         len--;
 201         // first we are going to figure out the total size....
 202         {
 203             int pass= 0;
 204             int total_length= 0;
 205             uint8_t *dst= NULL;
 206
 207             for(pass= 0; pass<2; pass++) {
 208                 const uint8_t *src= buf;
 209                 int src_len= len;
 210
 211                 do {
 212                     uint16_t nal_size = BE_16(src); // this going to be a problem if unaligned (can it be?)
 213
 214                     // consume the length of the aggregate...
 215                     src += 2;
 216                     src_len -= 2;
 217
 218                     if (nal_size <= src_len) {
 219                         if(pass==0) {
 220                             // counting...
 221                             total_length+= sizeof(start_sequence)+nal_size;
 222                         } else {
 223                             // copying
 224                             assert(dst);
 225                             memcpy(dst, start_sequence, sizeof(start_sequence));
 226                             dst+= sizeof(start_sequence);
 227                             memcpy(dst, src, nal_size);
 228 #ifdef DEBUG
 229                             data->packet_types_received[*src & 0x1f]++;
 230 #endif
 231                             dst+= nal_size;
 232                         }
 233                     } else {
 234                         av_log(NULL, AV_LOG_ERROR,
 235                                "nal size exceeds length: %d %d\n", nal_size, src_len);
 236                     }
 237
 238                     // eat what we handled...
 239                     src += nal_size;
 240                     src_len -= nal_size;
 241
 242                     if (src_len < 0)
 243                         av_log(NULL, AV_LOG_ERROR,
 244                                "Consumed more bytes than we got! (%d)\n", src_len);
 245                 } while (src_len > 2);      // because there could be rtp padding..
 246
 247                 if(pass==0) {
 248                     // now we know the total size of the packet (with the start sequences added)
 249                     av_new_packet(pkt, total_length);
 250                     dst= pkt->data;
 251                 } else {
 252                     assert(dst-pkt->data==total_length);
 253                 }
 254             }
 255         }
 256         break;
 257
 258     case 25:                   // STAP-B
 259     case 26:                   // MTAP-16
 260     case 27:                   // MTAP-24
 261     case 29:                   // FU-B
 262         av_log(NULL, AV_LOG_ERROR,
 263                "Unhandled type (%d) (See RFC for implementation details\n",
 264                type);
 265         result= -1;
 266         break;
 267
 268     case 28:                   // FU-A (fragmented nal)
 269         buf++;
 270         len--;                  // skip the fu_indicator
 271         {
 272             // these are the same as above, we just redo them here for clarity...
 273             uint8_t fu_indicator = nal;
 274             uint8_t fu_header = *buf;   // read the fu_header.
 275             uint8_t start_bit = (fu_header & 0x80) >> 7;
 276 //            uint8_t end_bit = (fu_header & 0x40) >> 6;
 277             uint8_t nal_type = (fu_header & 0x1f);
 278             uint8_t reconstructed_nal;
 279
 280             // reconstruct this packet's true nal; only the data follows..
 281             reconstructed_nal = fu_indicator & (0xe0);  // the original nal forbidden bit and NRI are stored in this packet's nal;
 282             reconstructed_nal |= (nal_type & 0x1f);
 283
 284             // skip the fu_header...
 285             buf++;
 286             len--;
 287
 288 #ifdef DEBUG
 289             if (start_bit)
 290                 data->packet_types_received[nal_type & 0x1f]++;
 291 #endif
 292             if(start_bit) {
 293                 // copy in the start sequence, and the reconstructed nal....
 294                 av_new_packet(pkt, sizeof(start_sequence)+sizeof(nal)+len);
 295                 memcpy(pkt->data, start_sequence, sizeof(start_sequence));
 296                 pkt->data[sizeof(start_sequence)]= reconstructed_nal;
 297                 memcpy(pkt->data+sizeof(start_sequence)+sizeof(nal), buf, len);
 298             } else {
 299                 av_new_packet(pkt, len);
 300                 memcpy(pkt->data, buf, len);
 301             }
 302         }
 303         break;
 304
 305     case 30:                   // undefined
 306     case 31:                   // undefined
 307     default:
 308         av_log(NULL, AV_LOG_ERROR, "Undefined type (%d)", type);
 309         result= -1;
 310         break;
 311     }
 312
 313     return result;
 314 }
 315
 316 /* ---------------- public code */
 317 static void *h264_new_extradata()
 318 {
 319     h264_rtp_extra_data *data =
 320         av_mallocz(sizeof(h264_rtp_extra_data) +
 321                    FF_INPUT_BUFFER_PADDING_SIZE);
 322
 323     if (data) {
 324         data->cookie = MAGIC_COOKIE;
 325     }
 326
 327     return data;
 328 }
 329
 330 static void h264_free_extradata(void *d)
 331 {
 332     h264_rtp_extra_data *data = (h264_rtp_extra_data *) d;
 333 #ifdef DEBUG
 334     int ii;
 335
 336     for (ii = 0; ii < 32; ii++) {
 337         if (data->packet_types_received[ii])
 338             av_log(NULL, AV_LOG_DEBUG, "Received %d packets of type %d\n",
 339                    data->packet_types_received[ii], ii);
 340     }
 341 #endif
 342
 343     assert(data);
 344     assert(data->cookie == MAGIC_COOKIE);
 345
 346     // avoid stale pointers (assert)
 347     data->cookie = DEAD_COOKIE;
 348
 349     // and clear out this...
 350     av_free(data);
 351 }
 352
 353 static int parse_h264_sdp_line(AVStream * stream, void *data,
 354                                const char *line)
 355 {
 356     AVCodecContext *codec = stream->codec;
 357     h264_rtp_extra_data *h264_data = (h264_rtp_extra_data *) data;
 358     const char *p = line;
 359
 360     assert(h264_data->cookie == MAGIC_COOKIE);
 361
 362     if (strstart(p, "framesize:", &p)) {
 363         char buf1[50];
 364         char *dst = buf1;
 365
 366         // remove the protocol identifier..
 367         while (*p && *p == ' ') p++; // strip spaces.
 368         while (*p && *p != ' ') p++; // eat protocol identifier
 369         while (*p && *p == ' ') p++; // strip trailing spaces.
 370         while (*p && *p != '-' && (buf1 - dst) < sizeof(buf1) - 1) {
 371             *dst++ = *p++;
 372         }
 373         *dst = '\0';
 374
 375         // a='framesize:96 320-240'
 376         // set our parameters..
 377         codec->width = atoi(buf1);
 378         codec->height = atoi(p + 1); // skip the -
 379         codec->pix_fmt = PIX_FMT_YUV420P;
 380     } else if (strstart(p, "fmtp:", &p)) {
 381         char attr[256];
 382         char value[4096];
 383
 384         // remove the protocol identifier..
 385         while (*p && *p == ' ') p++; // strip spaces.
 386         while (*p && *p != ' ') p++; // eat protocol identifier
 387         while (*p && *p == ' ') p++; // strip trailing spaces.
 388
 389         /* loop on each attribute */
 390         while (rtsp_next_attr_and_value
 391                (&p, attr, sizeof(attr), value, sizeof(value))) {
 392             /* grab the codec extra_data from the config parameter of the fmtp line */
 393             sdp_parse_fmtp_config_h264(stream, h264_data, attr, value);
 394         }
 395     } else if (strstart(p, "cliprect:", &p)) {
 396         // could use this if we wanted.
 397     }
 398
 399     av_set_pts_info(stream, 33, 1, 90000);      // 33 should be right, because the pts is 64 bit? (done elsewhere; this is a one time thing)
 400
 401     return 0;                   // keep processing it the normal way...
 402 }
 403
 404 /**
 405 This is the structure for expanding on the dynamic rtp protocols (makes everything static. yay!)
 406 */
 407 RTPDynamicProtocolHandler ff_h264_dynamic_handler = {
 408     "H264",
 409     CODEC_TYPE_VIDEO,
 410     CODEC_ID_H264,
 411     parse_h264_sdp_line,
 412     h264_new_extradata,
 413     h264_free_extradata,
 414     h264_handle_packet
 415 };