FFmpeg  4.3.9
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 FFmpeg.
7  *
8  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * @brief MPEG-4 / RTP Code
26  * @author Fabrice Bellard
27  * @author Romain Degez
28  */
29 
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 
38 /** Structure listing useful vars to parse RTP packet payload */
39 struct PayloadContext {
46  char *mode;
47 
48  /** mpeg 4 AU headers */
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 
74  /** Range for integer values */
75  struct Range {
76  int min;
77  int max;
78  } range;
79 } AttrNameMap;
80 
81 /* All known fmtp parameters and the corresponding RTPAttrTypeEnum */
82 #define ATTR_NAME_TYPE_INT 0
83 #define ATTR_NAME_TYPE_STR 1
84 static const AttrNameMap attr_names[] = {
85  { "SizeLength", ATTR_NAME_TYPE_INT,
86  offsetof(PayloadContext, sizelength),
87  {0, 32} }, // SizeLength number of bits used to encode AU-size integer value
88  { "IndexLength", ATTR_NAME_TYPE_INT,
89  offsetof(PayloadContext, indexlength),
90  {0, 32} }, // IndexLength number of bits used to encode AU-Index integer value
91  { "IndexDeltaLength", ATTR_NAME_TYPE_INT,
93  {0, 32} }, // IndexDeltaLength number of bits to encode AU-Index-delta integer value
94  { "profile-level-id", ATTR_NAME_TYPE_INT,
96  {INT32_MIN, INT32_MAX} }, // It differs depending on StreamType
97  { "StreamType", ATTR_NAME_TYPE_INT,
98  offsetof(PayloadContext, streamtype),
99  {0x00, 0x3F} }, // Values from ISO/IEC 14496-1, 'StreamType Values' table
100  { "mode", ATTR_NAME_TYPE_STR,
101  offsetof(PayloadContext, mode),
102  {0} },
103  { NULL, -1, -1, {0} },
104 };
105 
107 {
108  av_freep(&data->au_headers);
109  av_freep(&data->mode);
110 }
111 
112 static int parse_fmtp_config(AVCodecParameters *par, const char *value)
113 {
114  /* decode the hexa encoded parameter */
115  int len = ff_hex_to_data(NULL, value), ret;
116 
117  if ((ret = ff_alloc_extradata(par, len)) < 0)
118  return ret;
119  ff_hex_to_data(par->extradata, value);
120  return 0;
121 }
122 
124 {
125  int au_headers_length, au_header_size, i;
126  GetBitContext getbitcontext;
127 
128  if (len < 2)
129  return AVERROR_INVALIDDATA;
130 
131  /* decode the first 2 bytes where the AUHeader sections are stored
132  length in bits */
133  au_headers_length = AV_RB16(buf);
134 
135  if (au_headers_length > RTP_MAX_PACKET_LENGTH)
136  return -1;
137 
138  data->au_headers_length_bytes = (au_headers_length + 7) / 8;
139 
140  /* skip AU headers length section (2 bytes) */
141  buf += 2;
142  len -= 2;
143 
144  if (len < data->au_headers_length_bytes)
145  return AVERROR_INVALIDDATA;
146 
147  init_get_bits(&getbitcontext, buf, data->au_headers_length_bytes * 8);
148 
149  /* XXX: Wrong if optional additional sections are present (cts, dts etc...) */
150  au_header_size = data->sizelength + data->indexlength;
151  if (au_header_size <= 0 || (au_headers_length % au_header_size != 0))
152  return -1;
153 
154  data->nb_au_headers = au_headers_length / au_header_size;
155  if (!data->au_headers || data->au_headers_allocated < data->nb_au_headers) {
156  av_free(data->au_headers);
157  data->au_headers = av_malloc(sizeof(struct AUHeaders) * data->nb_au_headers);
158  if (!data->au_headers)
159  return AVERROR(ENOMEM);
160  data->au_headers_allocated = data->nb_au_headers;
161  }
162 
163  for (i = 0; i < data->nb_au_headers; ++i) {
164  data->au_headers[i].size = get_bits_long(&getbitcontext, data->sizelength);
165  data->au_headers[i].index = get_bits_long(&getbitcontext, data->indexlength);
166  }
167 
168  return 0;
169 }
170 
171 
172 /* Follows RFC 3640 */
174  AVStream *st, AVPacket *pkt, uint32_t *timestamp,
175  const uint8_t *buf, int len, uint16_t seq,
176  int flags)
177 {
178  int ret;
179 
180 
181  if (!buf) {
182  if (data->cur_au_index > data->nb_au_headers) {
183  av_log(ctx, AV_LOG_ERROR, "Invalid parser state\n");
184  return AVERROR_INVALIDDATA;
185  }
186  if (data->buf_size - data->buf_pos < data->au_headers[data->cur_au_index].size) {
187  av_log(ctx, AV_LOG_ERROR, "Invalid AU size\n");
188  return AVERROR_INVALIDDATA;
189  }
190  if ((ret = av_new_packet(pkt, data->au_headers[data->cur_au_index].size)) < 0) {
191  av_log(ctx, AV_LOG_ERROR, "Out of memory\n");
192  return ret;
193  }
194  memcpy(pkt->data, &data->buf[data->buf_pos], data->au_headers[data->cur_au_index].size);
195  data->buf_pos += data->au_headers[data->cur_au_index].size;
196  pkt->stream_index = st->index;
197  data->cur_au_index++;
198 
199  if (data->cur_au_index == data->nb_au_headers) {
200  data->buf_pos = 0;
201  return 0;
202  }
203 
204  return 1;
205  }
206 
207  if (rtp_parse_mp4_au(data, buf, len)) {
208  av_log(ctx, AV_LOG_ERROR, "Error parsing AU headers\n");
209  return -1;
210  }
211 
212  buf += data->au_headers_length_bytes + 2;
213  len -= data->au_headers_length_bytes + 2;
214  if (data->nb_au_headers == 1 && len < data->au_headers[0].size) {
215  /* Packet is fragmented */
216 
217  if (!data->buf_pos) {
218  if (data->au_headers[0].size > MAX_AAC_HBR_FRAME_SIZE) {
219  av_log(ctx, AV_LOG_ERROR, "Invalid AU size\n");
220  return AVERROR_INVALIDDATA;
221  }
222 
223  data->buf_size = data->au_headers[0].size;
224  data->timestamp = *timestamp;
225  }
226 
227  if (data->timestamp != *timestamp ||
228  data->au_headers[0].size != data->buf_size ||
229  data->buf_pos + len > MAX_AAC_HBR_FRAME_SIZE) {
230  data->buf_pos = 0;
231  data->buf_size = 0;
232  av_log(ctx, AV_LOG_ERROR, "Invalid packet received\n");
233  return AVERROR_INVALIDDATA;
234  }
235 
236  memcpy(&data->buf[data->buf_pos], buf, len);
237  data->buf_pos += len;
238 
239  if (!(flags & RTP_FLAG_MARKER))
240  return AVERROR(EAGAIN);
241 
242  if (data->buf_pos != data->buf_size) {
243  data->buf_pos = 0;
244  av_log(ctx, AV_LOG_ERROR, "Missed some packets, discarding frame\n");
245  return AVERROR_INVALIDDATA;
246  }
247 
248  data->buf_pos = 0;
249  ret = av_new_packet(pkt, data->buf_size);
250  if (ret < 0) {
251  av_log(ctx, AV_LOG_ERROR, "Out of memory\n");
252  return ret;
253  }
254  pkt->stream_index = st->index;
255 
256  memcpy(pkt->data, data->buf, data->buf_size);
257 
258  return 0;
259  }
260 
261  if (len < data->au_headers[0].size) {
262  av_log(ctx, AV_LOG_ERROR, "First AU larger than packet size\n");
263  return AVERROR_INVALIDDATA;
264  }
265  if ((ret = av_new_packet(pkt, data->au_headers[0].size)) < 0) {
266  av_log(ctx, AV_LOG_ERROR, "Out of memory\n");
267  return ret;
268  }
269  memcpy(pkt->data, buf, data->au_headers[0].size);
270  len -= data->au_headers[0].size;
271  buf += data->au_headers[0].size;
272  pkt->stream_index = st->index;
273 
274  if (len > 0 && data->nb_au_headers > 1) {
275  data->buf_size = FFMIN(len, sizeof(data->buf));
276  memcpy(data->buf, buf, data->buf_size);
277  data->cur_au_index = 1;
278  data->buf_pos = 0;
279  return 1;
280  }
281 
282  return 0;
283 }
284 
286  AVStream *stream, PayloadContext *data,
287  const char *attr, const char *value)
288 {
289  AVCodecParameters *par = stream->codecpar;
290  int res, i;
291 
292  if (!strcmp(attr, "config")) {
293  res = parse_fmtp_config(par, value);
294 
295  if (res < 0)
296  return res;
297  }
298 
299  if (par->codec_id == AV_CODEC_ID_AAC) {
300  /* Looking for a known attribute */
301  for (i = 0; attr_names[i].str; ++i) {
302  if (!av_strcasecmp(attr, attr_names[i].str)) {
303  if (attr_names[i].type == ATTR_NAME_TYPE_INT) {
304  char *end_ptr = NULL;
305  long long int val = strtoll(value, &end_ptr, 10);
306  if (end_ptr == value || end_ptr[0] != '\0') {
307  av_log(s, AV_LOG_ERROR,
308  "The %s field value is not a valid number: %s\n",
309  attr, value);
310  return AVERROR_INVALIDDATA;
311  }
312  if (val < attr_names[i].range.min ||
313  val > attr_names[i].range.max) {
314  av_log(s, AV_LOG_ERROR,
315  "fmtp field %s should be in range [%d,%d] (provided value: %lld)",
316  attr, attr_names[i].range.min, attr_names[i].range.max, val);
317  return AVERROR_INVALIDDATA;
318  }
319 
320  *(int *)((char *)data+
321  attr_names[i].offset) = (int) val;
322  } else if (attr_names[i].type == ATTR_NAME_TYPE_STR) {
323  char *val = av_strdup(value);
324  if (!val)
325  return AVERROR(ENOMEM);
326  *(char **)((char *)data+
327  attr_names[i].offset) = val;
328  }
329  }
330  }
331  }
332  return 0;
333 }
334 
335 static int parse_sdp_line(AVFormatContext *s, int st_index,
336  PayloadContext *data, const char *line)
337 {
338  const char *p;
339 
340  if (st_index < 0)
341  return 0;
342 
343  if (av_strstart(line, "fmtp:", &p))
344  return ff_parse_fmtp(s, s->streams[st_index], data, p, parse_fmtp);
345 
346  return 0;
347 }
348 
350  .enc_name = "MP4V-ES",
351  .codec_type = AVMEDIA_TYPE_VIDEO,
352  .codec_id = AV_CODEC_ID_MPEG4,
353  .need_parsing = AVSTREAM_PARSE_FULL,
354  .priv_data_size = sizeof(PayloadContext),
355  .parse_sdp_a_line = parse_sdp_line,
356 };
357 
359  .enc_name = "mpeg4-generic",
360  .codec_type = AVMEDIA_TYPE_AUDIO,
361  .codec_id = AV_CODEC_ID_AAC,
362  .priv_data_size = sizeof(PayloadContext),
363  .parse_sdp_a_line = parse_sdp_line,
364  .close = close_context,
366 };
AVPacket pkt
Definition: rtpdec_qt.c:37
const RTPDynamicProtocolHandler ff_mp4v_es_dynamic_handler
Definition: rtpdec_mpeg4.c:349
uint32_t offset
Definition: rtpdec_mpeg4.c:72
#define NULL
Definition: coverity.c:32
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define RTP_MAX_PACKET_LENGTH
Definition: rtpdec.h:36
static int parse_packet(AVFormatContext *s, AVPacket *pkt, int stream_index, int flush)
Parse a packet, add all split parts to parse_queue.
Definition: utils.c:1449
RTP/JPEG specific private data.
Definition: rdt.c:83
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int index
stream index in AVFormatContext
Definition: avformat.h:877
static void close_context(PayloadContext *data)
Definition: rtpdec_mpeg4.c:106
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
Macro definitions for various function/variable attributes.
Format I/O context.
Definition: avformat.h:1351
uint8_t
struct AttrNameMap::Range range
#define av_malloc(s)
static int parse_fmtp(AVFormatContext *s, AVStream *stream, PayloadContext *data, const char *attr, const char *value)
Definition: rtpdec_mpeg4.c:285
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1419
mpeg 4 AU headers
Definition: rtpdec_mpeg4.c:49
uint8_t * data
Definition: packet.h:355
bitstream reader API header.
#define av_log(a,...)
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:88
uint32_t timestamp
current frame timestamp
Definition: rtpdec_ac3.c:31
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#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:94
int au_headers_allocated
Definition: rtpdec_mpeg4.c:59
uint16_t type
Definition: rtpdec_mpeg4.c:71
int ff_alloc_extradata(AVCodecParameters *par, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0...
Definition: utils.c:3328
#define FFMIN(a, b)
Definition: common.h:96
int av_strcasecmp(const char *a, const char *b)
Locale-independent case-insensitive compare.
Definition: avstring.c:213
static int parse_fmtp_config(AVCodecParameters *par, const char *value)
Definition: rtpdec_mpeg4.c:112
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:173
AVFormatContext * ctx
Definition: movenc.c:48
#define ATTR_NAME_TYPE_INT
Definition: rtpdec_mpeg4.c:82
#define s(width, name)
Definition: cbs_vp9.c:257
const char * str
Definition: rtpdec_mpeg4.c:70
Stream structure.
Definition: avformat.h:876
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:253
AVIOContext * data
Definition: rtpdec_vp8.c:36
#define MAX_AAC_HBR_FRAME_SIZE
Definition: rtpdec_mpeg4.c:36
double value
Definition: eval.c:98
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:659
cl_device_type type
uint8_t * buf
the temporary storage buffer
Definition: rtpdec_asf.c:183
#define ATTR_NAME_TYPE_STR
Definition: rtpdec_mpeg4.c:83
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:887
static int rtp_parse_mp4_au(PayloadContext *data, const uint8_t *buf, int len)
Definition: rtpdec_mpeg4.c:123
int ff_hex_to_data(uint8_t *data, const char *p)
Parse a string of hexadecimal strings.
Definition: utils.c:4920
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition: get_bits.h:546
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:335
const RTPDynamicProtocolHandler ff_mpeg4_generic_dynamic_handler
Definition: rtpdec_mpeg4.c:358
#define flags(name, subs,...)
Definition: cbs_av1.c:576
static const AttrNameMap attr_names[]
Definition: rtpdec_mpeg4.c:84
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:34
full parsing and repack
Definition: avformat.h:795
Range for integer values.
Definition: rtpdec_mpeg4.c:75
#define av_free(p)
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
#define av_freep(p)
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1023
int au_headers_length_bytes
Definition: rtpdec_mpeg4.c:61
int stream_index
Definition: packet.h:357
static double val(void *priv, double ch)
Definition: aeval.c:76
This structure stores compressed data.
Definition: packet.h:332
mode
Use these values in ebur128_init (or&#39;ed).
Definition: ebur128.h:83