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 "network.h"
  45 #include <assert.h>
  46
  47 #include "rtp_internal.h"
  48 #include "rtp_h264.h"
  49 #include "base64.h"
  50
  51 /**
  52     RTP/H264 specific private data.
  53 */
  54 typedef struct h264_rtp_extra_data {
  55     unsigned long cookie;       ///< sanity check, to make sure we get the pointer we're expecting.
  56
  57     //sdp setup parameters
  58     uint8_t profile_idc;        ///< from the sdp setup parameters.
  59     uint8_t profile_iop;        ///< from the sdp setup parameters.
  60     uint8_t level_idc;          ///< from the sdp setup parameters.
  61     int packetization_mode;     ///< from the sdp setup parameters.
  62 #ifdef DEBUG
  63     int packet_types_received[32];
  64 #endif
  65 } h264_rtp_extra_data;
  66
  67 #define MAGIC_COOKIE (0xdeadbeef)       ///< Cookie for the extradata; to verify we are what we think we are, and that we haven't been freed.
  68 #define DEAD_COOKIE (0xdeaddead)        ///< Cookie for the extradata; once it is freed.
  69
  70 /* ---------------- private code */
  71 static void sdp_parse_fmtp_config_h264(AVStream * stream,
  72                                        h264_rtp_extra_data * h264_data,
  73                                        char *attr, char *value)
  74 {
  75     AVCodecContext *codec = stream->codec;
  76     assert(codec->codec_id == CODEC_ID_H264);
  77     assert(h264_data != NULL);
  78
  79     if (!strcmp(attr, "packetization-mode")) {
  80         av_log(NULL, AV_LOG_DEBUG, "H.264/RTP Packetization Mode: %d\n", atoi(attr));
  81         h264_data->packetization_mode = atoi(attr);
  82         /*
  83            Packetization Mode:
  84            0 or not present: Single NAL mode (Only nals from 1-23 are allowed)
  85            1: Non-interleaved Mode: 1-23, 24 (STAP-A), 28 (FU-A) are allowed.
  86            2: Interleaved Mode: 25 (STAP-B), 26 (MTAP16), 27 (MTAP24), 28 (FU-A), and 29 (FU-B) are allowed.
  87          */
  88         if (h264_data->packetization_mode > 1)
  89             av_log(stream, AV_LOG_ERROR,
  90                    "H.264/RTP Interleaved RTP mode is not supported yet.");
  91     } else if (!strcmp(attr, "profile-level-id")) {
  92         if (strlen(value) == 6) {
  93             char buffer[3];
  94             // 6 characters=3 bytes, in hex.
  95             uint8_t profile_idc;
  96             uint8_t profile_iop;
  97             uint8_t level_idc;
  98
  99             buffer[0] = value[0]; buffer[1] = value[1]; buffer[2] = '\0';
 100             profile_idc = strtol(buffer, NULL, 16);
 101             buffer[0] = value[2]; buffer[1] = value[3];
 102             profile_iop = strtol(buffer, NULL, 16);
 103             buffer[0] = value[4]; buffer[1] = value[5];
 104             level_idc = strtol(buffer, NULL, 16);
 105
 106             // set the parameters...
 107             av_log(NULL, AV_LOG_DEBUG,
 108                    "H.264/RTP Profile IDC: %x Profile IOP: %x Level: %x\n",
 109                    profile_idc, profile_iop, level_idc);
 110             h264_data->profile_idc = profile_idc;
 111             h264_data->profile_iop = profile_iop;
 112             h264_data->level_idc = level_idc;
 113         }
 114     } else  if (!strcmp(attr, "sprop-parameter-sets")) {
 115         uint8_t start_sequence[]= { 0, 0, 1 };
 116         codec->extradata_size= 0;
 117         codec->extradata= NULL;
 118
 119         while (*value) {
 120             char base64packet[1024];
 121             uint8_t decoded_packet[1024];
 122             uint32_t packet_size;
 123             char *dst = base64packet;
 124
 125             while (*value && *value != ','
 126                    && (dst - base64packet) < sizeof(base64packet) - 1) {
 127                 *dst++ = *value++;
 128             }
 129             *dst++ = '\0';
 130
 131             if (*value == ',')
 132                 value++;
 133
 134             packet_size= av_base64_decode(decoded_packet, base64packet, sizeof(decoded_packet));
 135             if (packet_size) {
 136                 uint8_t *dest= av_malloc(packet_size+sizeof(start_sequence)+codec->extradata_size);
 137                 if(dest)
 138                 {
 139                     if(codec->extradata_size)
 140                     {
 141                         // av_realloc?
 142                         memcpy(dest, codec->extradata, codec->extradata_size);
 143                         av_free(codec->extradata);
 144                     }
 145
 146                     memcpy(dest+codec->extradata_size, start_sequence, sizeof(start_sequence));
 147                     memcpy(dest+codec->extradata_size+sizeof(start_sequence), decoded_packet, packet_size);
 148
 149                     codec->extradata= dest;
 150                     codec->extradata_size+= sizeof(start_sequence)+packet_size;
 151                 } else {
 152                     av_log(NULL, AV_LOG_ERROR, "H.264/RTP Unable to allocate memory for extradata!");
 153                 }
 154             }
 155         }
 156         av_log(NULL, AV_LOG_DEBUG, "H.264/RTP Extradata set to %p (size: %d)!", codec->extradata, codec->extradata_size);
 157     }
 158 }
 159
 160 // return 0 on packet, no more left, 1 on packet, 1 on partial packet...
 161 static int h264_handle_packet(RTPDemuxContext * s,
 162                               AVPacket * pkt,
 163                               uint32_t * timestamp,
 164                               const uint8_t * buf,
 165                               int len)
 166 {
 167 //    h264_rtp_extra_data *data = s->dynamic_protocol_context;
 168     uint8_t nal = buf[0];
 169     uint8_t type = (nal & 0x1f);
 170     int result= 0;
 171     uint8_t start_sequence[]= {0, 0, 1};
 172
 173     assert(data);
 174     assert(data->cookie == MAGIC_COOKIE);
 175     assert(buf);
 176
 177     if (type >= 1 && type <= 23)
 178         type = 1;              // simplify the case. (these are all the nal types used internally by the h264 codec)
 179     switch (type) {
 180     case 0:                    // undefined;
 181         result= -1;
 182         break;
 183
 184     case 1:
 185         av_new_packet(pkt, len+sizeof(start_sequence));
 186         memcpy(pkt->data, start_sequence, sizeof(start_sequence));
 187         memcpy(pkt->data+sizeof(start_sequence), buf, len);
 188 #ifdef DEBUG
 189         data->packet_types_received[nal & 0x1f]++;
 190 #endif
 191         break;
 192
 193     case 24:                   // STAP-A (one packet, multiple nals)
 194         // consume the STAP-A NAL
 195         buf++;
 196         len--;
 197         // first we are going to figure out the total size....
 198         {
 199             int pass= 0;
 200             int total_length= 0;
 201             uint8_t *dst= NULL;
 202
 203             for(pass= 0; pass<2; pass++) {
 204                 const uint8_t *src= buf;
 205                 int src_len= len;
 206
 207                 do {
 208                     uint16_t nal_size = AV_RB16(src); // this going to be a problem if unaligned (can it be?)
 209
 210                     // consume the length of the aggregate...
 211                     src += 2;
 212                     src_len -= 2;
 213
 214                     if (nal_size <= src_len) {
 215                         if(pass==0) {
 216                             // counting...
 217                             total_length+= sizeof(start_sequence)+nal_size;
 218                         } else {
 219                             // copying
 220                             assert(dst);
 221                             memcpy(dst, start_sequence, sizeof(start_sequence));
 222                             dst+= sizeof(start_sequence);
 223                             memcpy(dst, src, nal_size);
 224 #ifdef DEBUG
 225                             data->packet_types_received[*src & 0x1f]++;
 226 #endif
 227                             dst+= nal_size;
 228                         }
 229                     } else {
 230                         av_log(NULL, AV_LOG_ERROR,
 231                                "nal size exceeds length: %d %d\n", nal_size, src_len);
 232                     }
 233
 234                     // eat what we handled...
 235                     src += nal_size;
 236                     src_len -= nal_size;
 237
 238                     if (src_len < 0)
 239                         av_log(NULL, AV_LOG_ERROR,
 240                                "Consumed more bytes than we got! (%d)\n", src_len);
 241                 } while (src_len > 2);      // because there could be rtp padding..
 242
 243                 if(pass==0) {
 244                     // now we know the total size of the packet (with the start sequences added)
 245                     av_new_packet(pkt, total_length);
 246                     dst= pkt->data;
 247                 } else {
 248                     assert(dst-pkt->data==total_length);
 249                 }
 250             }
 251         }
 252         break;
 253
 254     case 25:                   // STAP-B
 255     case 26:                   // MTAP-16
 256     case 27:                   // MTAP-24
 257     case 29:                   // FU-B
 258         av_log(NULL, AV_LOG_ERROR,
 259                "Unhandled type (%d) (See RFC for implementation details\n",
 260                type);
 261         result= -1;
 262         break;
 263
 264     case 28:                   // FU-A (fragmented nal)
 265         buf++;
 266         len--;                  // skip the fu_indicator
 267         {
 268             // these are the same as above, we just redo them here for clarity...
 269             uint8_t fu_indicator = nal;
 270             uint8_t fu_header = *buf;   // read the fu_header.
 271             uint8_t start_bit = (fu_header & 0x80) >> 7;
 272 //            uint8_t end_bit = (fu_header & 0x40) >> 6;
 273             uint8_t nal_type = (fu_header & 0x1f);
 274             uint8_t reconstructed_nal;
 275
 276             // reconstruct this packet's true nal; only the data follows..
 277             reconstructed_nal = fu_indicator & (0xe0);  // the original nal forbidden bit and NRI are stored in this packet's nal;
 278             reconstructed_nal |= (nal_type & 0x1f);
 279
 280             // skip the fu_header...
 281             buf++;
 282             len--;
 283
 284 #ifdef DEBUG
 285             if (start_bit)
 286                 data->packet_types_received[nal_type & 0x1f]++;
 287 #endif
 288             if(start_bit) {
 289                 // copy in the start sequence, and the reconstructed nal....
 290                 av_new_packet(pkt, sizeof(start_sequence)+sizeof(nal)+len);
 291                 memcpy(pkt->data, start_sequence, sizeof(start_sequence));
 292                 pkt->data[sizeof(start_sequence)]= reconstructed_nal;
 293                 memcpy(pkt->data+sizeof(start_sequence)+sizeof(nal), buf, len);
 294             } else {
 295                 av_new_packet(pkt, len);
 296                 memcpy(pkt->data, buf, len);
 297             }
 298         }
 299         break;
 300
 301     case 30:                   // undefined
 302     case 31:                   // undefined
 303     default:
 304         av_log(NULL, AV_LOG_ERROR, "Undefined type (%d)", type);
 305         result= -1;
 306         break;
 307     }
 308
 309     return result;
 310 }
 311
 312 /* ---------------- public code */
 313 static void *h264_new_extradata()
 314 {
 315     h264_rtp_extra_data *data =
 316         av_mallocz(sizeof(h264_rtp_extra_data) +
 317                    FF_INPUT_BUFFER_PADDING_SIZE);
 318
 319     if (data) {
 320         data->cookie = MAGIC_COOKIE;
 321     }
 322
 323     return data;
 324 }
 325
 326 static void h264_free_extradata(void *d)
 327 {
 328     h264_rtp_extra_data *data = (h264_rtp_extra_data *) d;
 329 #ifdef DEBUG
 330     int ii;
 331
 332     for (ii = 0; ii < 32; ii++) {
 333         if (data->packet_types_received[ii])
 334             av_log(NULL, AV_LOG_DEBUG, "Received %d packets of type %d\n",
 335                    data->packet_types_received[ii], ii);
 336     }
 337 #endif
 338
 339     assert(data);
 340     assert(data->cookie == MAGIC_COOKIE);
 341
 342     // avoid stale pointers (assert)
 343     data->cookie = DEAD_COOKIE;
 344
 345     // and clear out this...
 346     av_free(data);
 347 }
 348
 349 static int parse_h264_sdp_line(AVStream * stream, void *data,
 350                                const char *line)
 351 {
 352     AVCodecContext *codec = stream->codec;
 353     h264_rtp_extra_data *h264_data = (h264_rtp_extra_data *) data;
 354     const char *p = line;
 355
 356     assert(h264_data->cookie == MAGIC_COOKIE);
 357
 358     if (strstart(p, "framesize:", &p)) {
 359         char buf1[50];
 360         char *dst = buf1;
 361
 362         // remove the protocol identifier..
 363         while (*p && *p == ' ') p++; // strip spaces.
 364         while (*p && *p != ' ') p++; // eat protocol identifier
 365         while (*p && *p == ' ') p++; // strip trailing spaces.
 366         while (*p && *p != '-' && (buf1 - dst) < sizeof(buf1) - 1) {
 367             *dst++ = *p++;
 368         }
 369         *dst = '\0';
 370
 371         // a='framesize:96 320-240'
 372         // set our parameters..
 373         codec->width = atoi(buf1);
 374         codec->height = atoi(p + 1); // skip the -
 375         codec->pix_fmt = PIX_FMT_YUV420P;
 376     } else if (strstart(p, "fmtp:", &p)) {
 377         char attr[256];
 378         char value[4096];
 379
 380         // remove the protocol identifier..
 381         while (*p && *p == ' ') p++; // strip spaces.
 382         while (*p && *p != ' ') p++; // eat protocol identifier
 383         while (*p && *p == ' ') p++; // strip trailing spaces.
 384
 385         /* loop on each attribute */
 386         while (rtsp_next_attr_and_value
 387                (&p, attr, sizeof(attr), value, sizeof(value))) {
 388             /* grab the codec extra_data from the config parameter of the fmtp line */
 389             sdp_parse_fmtp_config_h264(stream, h264_data, attr, value);
 390         }
 391     } else if (strstart(p, "cliprect:", &p)) {
 392         // could use this if we wanted.
 393     }
 394
 395     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)
 396
 397     return 0;                   // keep processing it the normal way...
 398 }
 399
 400 /**
 401 This is the structure for expanding on the dynamic rtp protocols (makes everything static. yay!)
 402 */
 403 RTPDynamicProtocolHandler ff_h264_dynamic_handler = {
 404     "H264",
 405     CODEC_TYPE_VIDEO,
 406     CODEC_ID_H264,
 407     parse_h264_sdp_line,
 408     h264_new_extradata,
 409     h264_free_extradata,
 410     h264_handle_packet
 411 };