Libav
rtpdec_mpeg4.c
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1 /*
2  * Common code for the RTP depacketization of MPEG-4 formats.
3  * Copyright (c) 2010 Fabrice Bellard
4  * Romain Degez
5  *
6  * This file is part of Libav.
7  *
8  * Libav is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * Libav is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
30 #include "rtpdec_formats.h"
31 #include "internal.h"
32 #include "libavutil/attributes.h"
33 #include "libavutil/avstring.h"
34 #include "libavcodec/get_bits.h"
35 
36 #define MAX_AAC_HBR_FRAME_SIZE 8191
37 
39 struct PayloadContext {
46  char *mode;
47 
49  struct AUHeaders {
50  int size;
51  int index;
52  int cts_flag;
53  int cts;
54  int dts_flag;
55  int dts;
56  int rap_flag;
58  } *au_headers;
63 
66  uint32_t timestamp;
67 };
68 
69 typedef struct AttrNameMap {
70  const char *str;
71  uint16_t type;
72  uint32_t offset;
73 } AttrNameMap;
74 
75 /* All known fmtp parameters and the corresponding RTPAttrTypeEnum */
76 #define ATTR_NAME_TYPE_INT 0
77 #define ATTR_NAME_TYPE_STR 1
78 static const AttrNameMap attr_names[] = {
79  { "SizeLength", ATTR_NAME_TYPE_INT,
80  offsetof(PayloadContext, sizelength) },
81  { "IndexLength", ATTR_NAME_TYPE_INT,
82  offsetof(PayloadContext, indexlength) },
83  { "IndexDeltaLength", ATTR_NAME_TYPE_INT,
84  offsetof(PayloadContext, indexdeltalength) },
85  { "profile-level-id", ATTR_NAME_TYPE_INT,
86  offsetof(PayloadContext, profile_level_id) },
87  { "StreamType", ATTR_NAME_TYPE_INT,
88  offsetof(PayloadContext, streamtype) },
89  { "mode", ATTR_NAME_TYPE_STR,
90  offsetof(PayloadContext, mode) },
91  { NULL, -1, -1 },
92 };
93 
95 {
96  av_free(data->au_headers);
97  av_free(data->mode);
98 }
99 
100 static int parse_fmtp_config(AVCodecParameters *par, char *value)
101 {
102  /* decode the hexa encoded parameter */
103  int len = ff_hex_to_data(NULL, value);
104  av_free(par->extradata);
106  if (!par->extradata)
107  return AVERROR(ENOMEM);
108  par->extradata_size = len;
109  ff_hex_to_data(par->extradata, value);
110  return 0;
111 }
112 
114 {
115  int au_headers_length, au_header_size, i;
116  GetBitContext getbitcontext;
117 
118  if (len < 2)
119  return AVERROR_INVALIDDATA;
120 
121  /* decode the first 2 bytes where the AUHeader sections are stored
122  length in bits */
123  au_headers_length = AV_RB16(buf);
124 
125  if (au_headers_length > RTP_MAX_PACKET_LENGTH)
126  return -1;
127 
128  data->au_headers_length_bytes = (au_headers_length + 7) / 8;
129 
130  /* skip AU headers length section (2 bytes) */
131  buf += 2;
132  len -= 2;
133 
134  if (len < data->au_headers_length_bytes)
135  return AVERROR_INVALIDDATA;
136 
137  init_get_bits(&getbitcontext, buf, data->au_headers_length_bytes * 8);
138 
139  /* XXX: Wrong if optional additional sections are present (cts, dts etc...) */
140  au_header_size = data->sizelength + data->indexlength;
141  if (au_header_size <= 0 || (au_headers_length % au_header_size != 0))
142  return -1;
143 
144  data->nb_au_headers = au_headers_length / au_header_size;
145  if (!data->au_headers || data->au_headers_allocated < data->nb_au_headers) {
146  av_free(data->au_headers);
147  data->au_headers = av_malloc(sizeof(struct AUHeaders) * data->nb_au_headers);
148  if (!data->au_headers)
149  return AVERROR(ENOMEM);
150  data->au_headers_allocated = data->nb_au_headers;
151  }
152 
153  for (i = 0; i < data->nb_au_headers; ++i) {
154  data->au_headers[i].size = get_bits_long(&getbitcontext, data->sizelength);
155  data->au_headers[i].index = get_bits_long(&getbitcontext, data->indexlength);
156  }
157 
158  return 0;
159 }
160 
161 
162 /* Follows RFC 3640 */
164  AVStream *st, AVPacket *pkt, uint32_t *timestamp,
165  const uint8_t *buf, int len, uint16_t seq,
166  int flags)
167 {
168  int ret;
169 
170  if (!buf) {
171  if (data->cur_au_index > data->nb_au_headers) {
172  av_log(ctx, AV_LOG_ERROR, "Invalid parser state\n");
173  return AVERROR_INVALIDDATA;
174  }
175  if (data->buf_size - data->buf_pos < data->au_headers[data->cur_au_index].size) {
176  av_log(ctx, AV_LOG_ERROR, "Invalid AU size\n");
177  return AVERROR_INVALIDDATA;
178  }
179  if ((ret = av_new_packet(pkt, data->au_headers[data->cur_au_index].size)) < 0) {
180  av_log(ctx, AV_LOG_ERROR, "Out of memory\n");
181  return ret;
182  }
183  memcpy(pkt->data, &data->buf[data->buf_pos], data->au_headers[data->cur_au_index].size);
184  data->buf_pos += data->au_headers[data->cur_au_index].size;
185  pkt->stream_index = st->index;
186  data->cur_au_index++;
187 
188  if (data->cur_au_index == data->nb_au_headers) {
189  data->buf_pos = 0;
190  return 0;
191  }
192 
193  return 1;
194  }
195 
196  if (rtp_parse_mp4_au(data, buf, len)) {
197  av_log(ctx, AV_LOG_ERROR, "Error parsing AU headers\n");
198  return -1;
199  }
200 
201  buf += data->au_headers_length_bytes + 2;
202  len -= data->au_headers_length_bytes + 2;
203  if (data->nb_au_headers == 1 && len < data->au_headers[0].size) {
204  /* Packet is fragmented */
205 
206  if (!data->buf_pos) {
207  if (data->au_headers[0].size > MAX_AAC_HBR_FRAME_SIZE) {
208  av_log(ctx, AV_LOG_ERROR, "Invalid AU size\n");
209  return AVERROR_INVALIDDATA;
210  }
211 
212  data->buf_size = data->au_headers[0].size;
213  data->timestamp = *timestamp;
214  }
215 
216  if (data->timestamp != *timestamp ||
217  data->au_headers[0].size != data->buf_size ||
218  data->buf_pos + len > MAX_AAC_HBR_FRAME_SIZE) {
219  data->buf_pos = 0;
220  data->buf_size = 0;
221  av_log(ctx, AV_LOG_ERROR, "Invalid packet received\n");
222  return AVERROR_INVALIDDATA;
223  }
224 
225  memcpy(&data->buf[data->buf_pos], buf, len);
226  data->buf_pos += len;
227 
228  if (!(flags & RTP_FLAG_MARKER))
229  return AVERROR(EAGAIN);
230 
231  if (data->buf_pos != data->buf_size) {
232  data->buf_pos = 0;
233  av_log(ctx, AV_LOG_ERROR, "Missed some packets, discarding frame\n");
234  return AVERROR_INVALIDDATA;
235  }
236 
237  data->buf_pos = 0;
238  ret = av_new_packet(pkt, data->buf_size);
239  if (ret < 0) {
240  av_log(ctx, AV_LOG_ERROR, "Out of memory\n");
241  return ret;
242  }
243  pkt->stream_index = st->index;
244 
245  memcpy(pkt->data, data->buf, data->buf_size);
246 
247  return 0;
248  }
249 
250  if (len < data->au_headers[0].size) {
251  av_log(ctx, AV_LOG_ERROR, "First AU larger than packet size\n");
252  return AVERROR_INVALIDDATA;
253  }
254  if ((ret = av_new_packet(pkt, data->au_headers[0].size)) < 0) {
255  av_log(ctx, AV_LOG_ERROR, "Out of memory\n");
256  return ret;
257  }
258  memcpy(pkt->data, buf, data->au_headers[0].size);
259  len -= data->au_headers[0].size;
260  buf += data->au_headers[0].size;
261  pkt->stream_index = st->index;
262 
263  if (len > 0 && data->nb_au_headers > 1) {
264  data->buf_size = FFMIN(len, sizeof(data->buf));
265  memcpy(data->buf, buf, data->buf_size);
266  data->cur_au_index = 1;
267  data->buf_pos = 0;
268  return 1;
269  }
270 
271  return 0;
272 }
273 
275  AVStream *stream, PayloadContext *data,
276  const char *attr, const char *value)
277 {
278  AVCodecParameters *par = stream->codecpar;
279  int res, i;
280 
281  if (!strcmp(attr, "config")) {
282  res = parse_fmtp_config(par, value);
283 
284  if (res < 0)
285  return res;
286  }
287 
288  if (par->codec_id == AV_CODEC_ID_AAC) {
289  /* Looking for a known attribute */
290  for (i = 0; attr_names[i].str; ++i) {
291  if (!av_strcasecmp(attr, attr_names[i].str)) {
292  if (attr_names[i].type == ATTR_NAME_TYPE_INT) {
293  int val = atoi(value);
294  if (val > 32) {
295  av_log(s, AV_LOG_ERROR,
296  "The %s field size is invalid (%d).",
297  attr, val);
298  return AVERROR_INVALIDDATA;
299  }
300  *(int *)((char *)data+
301  attr_names[i].offset) = val;
302  } else if (attr_names[i].type == ATTR_NAME_TYPE_STR) {
303  char *val = av_strdup(value);
304  if (!val)
305  return AVERROR(ENOMEM);
306  *(char **)((char *)data+
307  attr_names[i].offset) = val;
308  }
309  }
310  }
311  }
312  return 0;
313 }
314 
315 static int parse_sdp_line(AVFormatContext *s, int st_index,
316  PayloadContext *data, const char *line)
317 {
318  const char *p;
319 
320  if (st_index < 0)
321  return 0;
322 
323  if (av_strstart(line, "fmtp:", &p))
324  return ff_parse_fmtp(s, s->streams[st_index], data, p, parse_fmtp);
325 
326  return 0;
327 }
328 
330  .enc_name = "MP4V-ES",
331  .codec_type = AVMEDIA_TYPE_VIDEO,
332  .codec_id = AV_CODEC_ID_MPEG4,
333  .need_parsing = AVSTREAM_PARSE_FULL,
334  .priv_data_size = sizeof(PayloadContext),
335  .parse_sdp_a_line = parse_sdp_line,
336 };
337 
339  .enc_name = "mpeg4-generic",
340  .codec_type = AVMEDIA_TYPE_AUDIO,
341  .codec_id = AV_CODEC_ID_AAC,
342  .priv_data_size = sizeof(PayloadContext),
343  .parse_sdp_a_line = parse_sdp_line,
344  .close = close_context,
346 };
AVPacket pkt
Definition: rtpdec_qt.c:37
uint32_t offset
Definition: rtpdec_mpeg4.c:72
void * av_malloc(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:62
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
#define RTP_MAX_PACKET_LENGTH
Definition: rtpdec.h:36
RTP/JPEG specific private data.
Definition: rdt.c:83
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3483
int index
stream index in AVFormatContext
Definition: avformat.h:706
av_log(ac->avr, AV_LOG_TRACE, "%d samples - audio_convert: %s to %s (%s)\, len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt), use_generic ? ac->func_descr_generic :ac->func_descr)
static void close_context(PayloadContext *data)
Definition: rtpdec_mpeg4.c:94
static int parse_fmtp_config(AVCodecParameters *par, char *value)
Definition: rtpdec_mpeg4.c:100
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3475
RTPDynamicProtocolHandler ff_mpeg4_generic_dynamic_handler
Definition: rtpdec_mpeg4.c:338
Macro definitions for various function/variable attributes.
Format I/O context.
Definition: avformat.h:940
uint8_t
static int parse_fmtp(AVFormatContext *s, AVStream *stream, PayloadContext *data, const char *attr, const char *value)
Definition: rtpdec_mpeg4.c:274
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1008
mpeg 4 AU headers
Definition: rtpdec_mpeg4.c:49
uint8_t * data
Definition: avcodec.h:1346
static int flags
Definition: log.c:50
bitstream reader API header.
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:84
uint32_t timestamp
current frame timestamp
Definition: rtpdec_ac3.c:31
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:124
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:190
#define RTP_FLAG_MARKER
RTP marker bit was set for this packet.
Definition: rtpdec.h:93
#define AV_RB16
Definition: intreadwrite.h:53
#define AVERROR(e)
Definition: error.h:43
Definition: graph2dot.c:48
#define FFMAX(a, b)
Definition: common.h:64
int au_headers_allocated
Definition: rtpdec_mpeg4.c:59
int extradata_size
Size of the extradata content in bytes.
Definition: avcodec.h:3501
uint16_t type
Definition: rtpdec_mpeg4.c:71
#define FFMIN(a, b)
Definition: common.h:66
int av_strcasecmp(const char *a, const char *b)
Definition: avstring.c:156
RTPDynamicProtocolHandler ff_mp4v_es_dynamic_handler
Definition: rtpdec_mpeg4.c:329
static int aac_parse_packet(AVFormatContext *ctx, PayloadContext *data, AVStream *st, AVPacket *pkt, uint32_t *timestamp, const uint8_t *buf, int len, uint16_t seq, int flags)
Definition: rtpdec_mpeg4.c:163
AVFormatContext * ctx
Definition: movenc.c:48
#define ATTR_NAME_TYPE_INT
Definition: rtpdec_mpeg4.c:76
const char * str
Definition: rtpdec_mpeg4.c:70
Stream structure.
Definition: avformat.h:705
NULL
Definition: eval.c:55
AVIOContext * data
Definition: rtpdec_vp8.c:36
char * av_strdup(const char *s)
Duplicate the string s.
Definition: mem.c:219
#define MAX_AAC_HBR_FRAME_SIZE
Definition: rtpdec_mpeg4.c:36
struct PayloadContext::AUHeaders * au_headers
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:362
uint8_t * buf
the temporary storage buffer
Definition: rtpdec_asf.c:168
#define ATTR_NAME_TYPE_STR
Definition: rtpdec_mpeg4.c:77
int ff_parse_fmtp(AVFormatContext *s, AVStream *stream, PayloadContext *data, const char *p, int(*parse_fmtp)(AVFormatContext *s, AVStream *stream, PayloadContext *data, const char *attr, const char *value))
Definition: rtpdec.c:853
static int rtp_parse_mp4_au(PayloadContext *data, const uint8_t *buf, int len)
Definition: rtpdec_mpeg4.c:113
int ff_hex_to_data(uint8_t *data, const char *p)
Parse a string of hexadecimal strings.
Definition: utils.c:2958
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition: get_bits.h:300
const char * enc_name
Definition: rtpdec.h:116
static int parse_sdp_line(AVFormatContext *s, int st_index, PayloadContext *data, const char *line)
Definition: rtpdec_mpeg4.c:315
static const AttrNameMap attr_names[]
Definition: rtpdec_mpeg4.c:78
int av_strstart(const char *str, const char *pfx, const char **ptr)
Return non-zero if pfx is a prefix of str.
Definition: avstring.c:32
full parsing and repack
Definition: avformat.h:657
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:638
static int parse_packet(AVFormatContext *s, AVPacket *pkt, int stream_index)
Parse a packet, add all split parts to parse_queue.
Definition: utils.c:816
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3497
AVCodecParameters * codecpar
Definition: avformat.h:831
int au_headers_length_bytes
Definition: rtpdec_mpeg4.c:61
int stream_index
Definition: avcodec.h:1348
This structure stores compressed data.
Definition: avcodec.h:1323
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:211