Statistics
| Branch: | Revision:

ffmpeg / libavformat / rtpdec_h264.c @ b9b8ed2a

History | View | Annotate | Download (14.6 KB)

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 libavformat/rtpdec_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 "libavutil/base64.h"
40
#include "libavutil/avstring.h"
41
#include "libavcodec/get_bits.h"
42
#include "avformat.h"
43
#include "mpegts.h"
44

    
45
#include <unistd.h>
46
#include "network.h"
47
#include <assert.h>
48

    
49
#include "rtpdec.h"
50
#include "rtpdec_h264.h"
51

    
52
/**
53
    RTP/H264 specific private data.
54
*/
55
struct PayloadContext {
56
    unsigned long cookie;       ///< sanity check, to make sure we get the pointer we're expecting.
57

    
58
    //sdp setup parameters
59
    uint8_t profile_idc;        ///< from the sdp setup parameters.
60
    uint8_t profile_iop;        ///< from the sdp setup parameters.
61
    uint8_t level_idc;          ///< from the sdp setup parameters.
62
    int packetization_mode;     ///< from the sdp setup parameters.
63
#ifdef DEBUG
64
    int packet_types_received[32];
65
#endif
66
};
67

    
68
#define MAGIC_COOKIE (0xdeadbeef)       ///< Cookie for the extradata; to verify we are what we think we are, and that we haven't been freed.
69
#define DEAD_COOKIE (0xdeaddead)        ///< Cookie for the extradata; once it is freed.
70

    
71
/* ---------------- private code */
72
static void sdp_parse_fmtp_config_h264(AVStream * stream,
73
                                       PayloadContext * h264_data,
74
                                       char *attr, char *value)
75
{
76
    AVCodecContext *codec = stream->codec;
77
    assert(codec->codec_id == CODEC_ID_H264);
78
    assert(h264_data != NULL);
79

    
80
    if (!strcmp(attr, "packetization-mode")) {
81
        av_log(codec, AV_LOG_DEBUG, "RTP Packetization Mode: %d\n", atoi(value));
82
        h264_data->packetization_mode = atoi(value);
83
        /*
84
           Packetization Mode:
85
           0 or not present: Single NAL mode (Only nals from 1-23 are allowed)
86
           1: Non-interleaved Mode: 1-23, 24 (STAP-A), 28 (FU-A) are allowed.
87
           2: Interleaved Mode: 25 (STAP-B), 26 (MTAP16), 27 (MTAP24), 28 (FU-A), and 29 (FU-B) are allowed.
88
         */
89
        if (h264_data->packetization_mode > 1)
90
            av_log(codec, AV_LOG_ERROR,
91
                   "Interleaved RTP mode is not supported yet.");
92
    } else if (!strcmp(attr, "profile-level-id")) {
93
        if (strlen(value) == 6) {
94
            char buffer[3];
95
            // 6 characters=3 bytes, in hex.
96
            uint8_t profile_idc;
97
            uint8_t profile_iop;
98
            uint8_t level_idc;
99

    
100
            buffer[0] = value[0]; buffer[1] = value[1]; buffer[2] = '\0';
101
            profile_idc = strtol(buffer, NULL, 16);
102
            buffer[0] = value[2]; buffer[1] = value[3];
103
            profile_iop = strtol(buffer, NULL, 16);
104
            buffer[0] = value[4]; buffer[1] = value[5];
105
            level_idc = strtol(buffer, NULL, 16);
106

    
107
            // set the parameters...
108
            av_log(codec, AV_LOG_DEBUG,
109
                   "RTP Profile IDC: %x Profile IOP: %x Level: %x\n",
110
                   profile_idc, profile_iop, level_idc);
111
            h264_data->profile_idc = profile_idc;
112
            h264_data->profile_iop = profile_iop;
113
            h264_data->level_idc = level_idc;
114
        }
115
    } else  if (!strcmp(attr, "sprop-parameter-sets")) {
116
        uint8_t start_sequence[]= { 0, 0, 1 };
117
        codec->extradata_size= 0;
118
        codec->extradata= NULL;
119

    
120
        while (*value) {
121
            char base64packet[1024];
122
            uint8_t decoded_packet[1024];
123
            uint32_t packet_size;
124
            char *dst = base64packet;
125

    
126
            while (*value && *value != ','
127
                   && (dst - base64packet) < sizeof(base64packet) - 1) {
128
                *dst++ = *value++;
129
            }
130
            *dst++ = '\0';
131

    
132
            if (*value == ',')
133
                value++;
134

    
135
            packet_size= av_base64_decode(decoded_packet, base64packet, sizeof(decoded_packet));
136
            if (packet_size) {
137
                uint8_t *dest = av_malloc(packet_size + sizeof(start_sequence) +
138
                                         codec->extradata_size +
139
                                         FF_INPUT_BUFFER_PADDING_SIZE);
140
                if(dest)
141
                {
142
                    if(codec->extradata_size)
143
                    {
144
                        // av_realloc?
145
                        memcpy(dest, codec->extradata, codec->extradata_size);
146
                        av_free(codec->extradata);
147
                    }
148

    
149
                    memcpy(dest+codec->extradata_size, start_sequence, sizeof(start_sequence));
150
                    memcpy(dest+codec->extradata_size+sizeof(start_sequence), decoded_packet, packet_size);
151
                    memset(dest+codec->extradata_size+sizeof(start_sequence)+
152
                           packet_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
153

    
154
                    codec->extradata= dest;
155
                    codec->extradata_size+= sizeof(start_sequence)+packet_size;
156
                } else {
157
                    av_log(codec, AV_LOG_ERROR, "Unable to allocate memory for extradata!");
158
                }
159
            }
160
        }
161
        av_log(codec, AV_LOG_DEBUG, "Extradata set to %p (size: %d)!", codec->extradata, codec->extradata_size);
162
    }
163
}
164

    
165
// return 0 on packet, no more left, 1 on packet, 1 on partial packet...
166
static int h264_handle_packet(AVFormatContext *ctx,
167
                              PayloadContext *data,
168
                              AVStream *st,
169
                              AVPacket * pkt,
170
                              uint32_t * timestamp,
171
                              const uint8_t * buf,
172
                              int len, int flags)
173
{
174
    uint8_t nal = buf[0];
175
    uint8_t type = (nal & 0x1f);
176
    int result= 0;
177
    uint8_t start_sequence[]= {0, 0, 1};
178

    
179
#ifdef DEBUG
180
    assert(data);
181
    assert(data->cookie == MAGIC_COOKIE);
182
#endif
183
    assert(buf);
184

    
185
    if (type >= 1 && type <= 23)
186
        type = 1;              // simplify the case. (these are all the nal types used internally by the h264 codec)
187
    switch (type) {
188
    case 0:                    // undefined;
189
        result= -1;
190
        break;
191

    
192
    case 1:
193
        av_new_packet(pkt, len+sizeof(start_sequence));
194
        memcpy(pkt->data, start_sequence, sizeof(start_sequence));
195
        memcpy(pkt->data+sizeof(start_sequence), buf, len);
196
#ifdef DEBUG
197
        data->packet_types_received[nal & 0x1f]++;
198
#endif
199
        break;
200

    
201
    case 24:                   // STAP-A (one packet, multiple nals)
202
        // consume the STAP-A NAL
203
        buf++;
204
        len--;
205
        // first we are going to figure out the total size....
206
        {
207
            int pass= 0;
208
            int total_length= 0;
209
            uint8_t *dst= NULL;
210

    
211
            for(pass= 0; pass<2; pass++) {
212
                const uint8_t *src= buf;
213
                int src_len= len;
214

    
215
                do {
216
                    uint16_t nal_size = AV_RB16(src); // this going to be a problem if unaligned (can it be?)
217

    
218
                    // consume the length of the aggregate...
219
                    src += 2;
220
                    src_len -= 2;
221

    
222
                    if (nal_size <= src_len) {
223
                        if(pass==0) {
224
                            // counting...
225
                            total_length+= sizeof(start_sequence)+nal_size;
226
                        } else {
227
                            // copying
228
                            assert(dst);
229
                            memcpy(dst, start_sequence, sizeof(start_sequence));
230
                            dst+= sizeof(start_sequence);
231
                            memcpy(dst, src, nal_size);
232
#ifdef DEBUG
233
                            data->packet_types_received[*src & 0x1f]++;
234
#endif
235
                            dst+= nal_size;
236
                        }
237
                    } else {
238
                        av_log(ctx, AV_LOG_ERROR,
239
                               "nal size exceeds length: %d %d\n", nal_size, src_len);
240
                    }
241

    
242
                    // eat what we handled...
243
                    src += nal_size;
244
                    src_len -= nal_size;
245

    
246
                    if (src_len < 0)
247
                        av_log(ctx, AV_LOG_ERROR,
248
                               "Consumed more bytes than we got! (%d)\n", src_len);
249
                } while (src_len > 2);      // because there could be rtp padding..
250

    
251
                if(pass==0) {
252
                    // now we know the total size of the packet (with the start sequences added)
253
                    av_new_packet(pkt, total_length);
254
                    dst= pkt->data;
255
                } else {
256
                    assert(dst-pkt->data==total_length);
257
                }
258
            }
259
        }
260
        break;
261

    
262
    case 25:                   // STAP-B
263
    case 26:                   // MTAP-16
264
    case 27:                   // MTAP-24
265
    case 29:                   // FU-B
266
        av_log(ctx, AV_LOG_ERROR,
267
               "Unhandled type (%d) (See RFC for implementation details\n",
268
               type);
269
        result= -1;
270
        break;
271

    
272
    case 28:                   // FU-A (fragmented nal)
273
        buf++;
274
        len--;                  // skip the fu_indicator
275
        {
276
            // these are the same as above, we just redo them here for clarity...
277
            uint8_t fu_indicator = nal;
278
            uint8_t fu_header = *buf;   // read the fu_header.
279
            uint8_t start_bit = fu_header >> 7;
280
//            uint8_t end_bit = (fu_header & 0x40) >> 6;
281
            uint8_t nal_type = (fu_header & 0x1f);
282
            uint8_t reconstructed_nal;
283

    
284
            // reconstruct this packet's true nal; only the data follows..
285
            reconstructed_nal = fu_indicator & (0xe0);  // the original nal forbidden bit and NRI are stored in this packet's nal;
286
            reconstructed_nal |= nal_type;
287

    
288
            // skip the fu_header...
289
            buf++;
290
            len--;
291

    
292
#ifdef DEBUG
293
            if (start_bit)
294
                data->packet_types_received[nal_type]++;
295
#endif
296
            if(start_bit) {
297
                // copy in the start sequence, and the reconstructed nal....
298
                av_new_packet(pkt, sizeof(start_sequence)+sizeof(nal)+len);
299
                memcpy(pkt->data, start_sequence, sizeof(start_sequence));
300
                pkt->data[sizeof(start_sequence)]= reconstructed_nal;
301
                memcpy(pkt->data+sizeof(start_sequence)+sizeof(nal), buf, len);
302
            } else {
303
                av_new_packet(pkt, len);
304
                memcpy(pkt->data, buf, len);
305
            }
306
        }
307
        break;
308

    
309
    case 30:                   // undefined
310
    case 31:                   // undefined
311
    default:
312
        av_log(ctx, AV_LOG_ERROR, "Undefined type (%d)", type);
313
        result= -1;
314
        break;
315
    }
316

    
317
    pkt->stream_index = st->index;
318

    
319
    return result;
320
}
321

    
322
/* ---------------- public code */
323
static PayloadContext *h264_new_context(void)
324
{
325
    PayloadContext *data =
326
        av_mallocz(sizeof(PayloadContext) +
327
                   FF_INPUT_BUFFER_PADDING_SIZE);
328

    
329
    if (data) {
330
        data->cookie = MAGIC_COOKIE;
331
    }
332

    
333
    return data;
334
}
335

    
336
static void h264_free_context(PayloadContext *data)
337
{
338
#ifdef DEBUG
339
    int ii;
340

    
341
    for (ii = 0; ii < 32; ii++) {
342
        if (data->packet_types_received[ii])
343
            av_log(NULL, AV_LOG_DEBUG, "Received %d packets of type %d\n",
344
                   data->packet_types_received[ii], ii);
345
    }
346
#endif
347

    
348
    assert(data);
349
    assert(data->cookie == MAGIC_COOKIE);
350

    
351
    // avoid stale pointers (assert)
352
    data->cookie = DEAD_COOKIE;
353

    
354
    // and clear out this...
355
    av_free(data);
356
}
357

    
358
static int parse_h264_sdp_line(AVFormatContext *s, int st_index,
359
                               PayloadContext *h264_data, const char *line)
360
{
361
    AVStream *stream = s->streams[st_index];
362
    AVCodecContext *codec = stream->codec;
363
    const char *p = line;
364

    
365
    assert(h264_data->cookie == MAGIC_COOKIE);
366

    
367
    if (av_strstart(p, "framesize:", &p)) {
368
        char buf1[50];
369
        char *dst = buf1;
370

    
371
        // remove the protocol identifier..
372
        while (*p && *p == ' ') p++; // strip spaces.
373
        while (*p && *p != ' ') p++; // eat protocol identifier
374
        while (*p && *p == ' ') p++; // strip trailing spaces.
375
        while (*p && *p != '-' && (dst - buf1) < sizeof(buf1) - 1) {
376
            *dst++ = *p++;
377
        }
378
        *dst = '\0';
379

    
380
        // a='framesize:96 320-240'
381
        // set our parameters..
382
        codec->width = atoi(buf1);
383
        codec->height = atoi(p + 1); // skip the -
384
        codec->pix_fmt = PIX_FMT_YUV420P;
385
    } else if (av_strstart(p, "fmtp:", &p)) {
386
        char attr[256];
387
        char value[4096];
388

    
389
        // remove the protocol identifier..
390
        while (*p && *p == ' ') p++; // strip spaces.
391
        while (*p && *p != ' ') p++; // eat protocol identifier
392
        while (*p && *p == ' ') p++; // strip trailing spaces.
393

    
394
        /* loop on each attribute */
395
        while (ff_rtsp_next_attr_and_value
396
               (&p, attr, sizeof(attr), value, sizeof(value))) {
397
            /* grab the codec extra_data from the config parameter of the fmtp line */
398
            sdp_parse_fmtp_config_h264(stream, h264_data, attr, value);
399
        }
400
    } else if (av_strstart(p, "cliprect:", &p)) {
401
        // could use this if we wanted.
402
    }
403

    
404
    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)
405

    
406
    return 0;                   // keep processing it the normal way...
407
}
408

    
409
/**
410
This is the structure for expanding on the dynamic rtp protocols (makes everything static. yay!)
411
*/
412
RTPDynamicProtocolHandler ff_h264_dynamic_handler = {
413
    .enc_name         = "H264",
414
    .codec_type       = CODEC_TYPE_VIDEO,
415
    .codec_id         = CODEC_ID_H264,
416
    .parse_sdp_a_line = parse_h264_sdp_line,
417
    .open             = h264_new_context,
418
    .close            = h264_free_context,
419
    .parse_packet     = h264_handle_packet
420
};