FFmpeg  4.0
prompeg.c
Go to the documentation of this file.
1 /*
2  * Pro-MPEG Code of Practice #3 Release 2 FEC
3  * Copyright (c) 2016 Mobibase, France (http://www.mobibase.com)
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
24  * Pro-MPEG Code of Practice #3 Release 2 FEC protocol
25  * @author Vlad Tarca <vlad.tarca@gmail.com>
26  */
27 
28 /*
29  * Reminder:
30 
31  [RFC 2733] FEC Packet Structure
32 
33  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
34  | RTP Header |
35  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
36  | FEC Header |
37  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
38  | FEC Payload |
39  | |
40  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
41 
42 
43  [RFC 3550] RTP header
44 
45  0 1 2 3
46  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
47  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
48  |V=2|P|X| CC |M| PT | sequence number |
49  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
50  | timestamp |
51  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
52  | synchronization source (SSRC) identifier |
53  +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
54  | contributing source (CSRC) identifiers |
55  | .... |
56  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
57 
58  [RFC 3550] RTP header extension (after CSRC)
59 
60  0 1 2 3
61  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
62  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
63  | defined by profile | length |
64  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
65  | header extension |
66  | .... |
67  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
68 
69  [Pro-MPEG COP3] FEC Header
70 
71  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
72  | SNBase low bits | length recovery |
73  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
74  |E| PT recovery | mask |
75  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
76  | TS recovery |
77  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
78  |X|D|type |index| offset | NA |SNBase ext bits|
79  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
80 
81  */
82 
83 #include "libavutil/avstring.h"
84 #include "libavutil/intreadwrite.h"
85 #include "libavutil/opt.h"
86 #include "libavutil/parseutils.h"
87 #include "libavutil/random_seed.h"
88 #include "avformat.h"
89 #include "config.h"
90 #include "url.h"
91 
92 #define PROMPEG_RTP_PT 0x60
93 #define PROMPEG_FEC_COL 0x0
94 #define PROMPEG_FEC_ROW 0x1
95 
96 typedef struct PrompegFec {
97  uint16_t sn;
98  uint32_t ts;
100 } PrompegFec;
101 
102 typedef struct PrompegContext {
103  const AVClass *class;
104  URLContext *fec_col_hd, *fec_row_hd;
105  PrompegFec **fec_arr, **fec_col_tmp, **fec_col, *fec_row;
106  int ttl;
107  uint8_t l, d;
109  uint16_t rtp_col_sn, rtp_row_sn;
110  uint16_t length_recovery;
112  int packet_idx, packet_idx_max;
116  int init;
117  int first;
119 
120 #define OFFSET(x) offsetof(PrompegContext, x)
121 #define E AV_OPT_FLAG_ENCODING_PARAM
122 
123 static const AVOption options[] = {
124  { "ttl", "Time to live (in milliseconds, multicast only)", OFFSET(ttl), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = E },
125  { "l", "FEC L", OFFSET(l), AV_OPT_TYPE_INT, { .i64 = 5 }, 4, 20, .flags = E },
126  { "d", "FEC D", OFFSET(d), AV_OPT_TYPE_INT, { .i64 = 5 }, 4, 20, .flags = E },
127  { NULL }
128 };
129 
130 static const AVClass prompeg_class = {
131  .class_name = "prompeg",
132  .item_name = av_default_item_name,
133  .option = options,
134  .version = LIBAVUTIL_VERSION_INT,
135 };
136 
137 static void xor_fast(const uint8_t *in1, const uint8_t *in2, uint8_t *out, int size) {
138  int i, n, s;
139 
140 #if HAVE_FAST_64BIT
141  uint64_t v1, v2;
142 
143  n = size / sizeof (uint64_t);
144  s = n * sizeof (uint64_t);
145 
146  for (i = 0; i < n; i++) {
147  v1 = AV_RN64A(in1);
148  v2 = AV_RN64A(in2);
149  AV_WN64A(out, v1 ^ v2);
150  in1 += 8;
151  in2 += 8;
152  out += 8;
153  }
154 #else
155  uint32_t v1, v2;
156 
157  n = size / sizeof (uint32_t);
158  s = n * sizeof (uint32_t);
159 
160  for (i = 0; i < n; i++) {
161  v1 = AV_RN32A(in1);
162  v2 = AV_RN32A(in2);
163  AV_WN32A(out, v1 ^ v2);
164  in1 += 4;
165  in2 += 4;
166  out += 4;
167  }
168 #endif
169 
170  n = size - s;
171 
172  for (i = 0; i < n; i++) {
173  out[i] = in1[i] ^ in2[i];
174  }
175 }
176 
178  uint8_t **bitstring) {
179  PrompegContext *s = h->priv_data;
180  uint8_t *b;
181 
182  if (size < 12 || (buf[0] & 0xc0) != 0x80 || (buf[1] & 0x7f) != 0x21) {
183  av_log(h, AV_LOG_ERROR, "Unsupported stream format (expected MPEG-TS over RTP)\n");
184  return AVERROR(EINVAL);
185  }
186  if (size != s->packet_size) {
187  av_log(h, AV_LOG_ERROR, "The RTP packet size must be constant (set pkt_size)\n");
188  return AVERROR(EINVAL);
189  }
190 
191  *bitstring = av_malloc(s->bitstring_size);
192  if (!*bitstring) {
193  av_log(h, AV_LOG_ERROR, "Failed to allocate the bitstring buffer\n");
194  return AVERROR(ENOMEM);
195  }
196  b = *bitstring;
197 
198  // P, X, CC
199  b[0] = buf[0] & 0x3f;
200  // M, PT
201  b[1] = buf[1];
202  // Timestamp
203  b[2] = buf[4];
204  b[3] = buf[5];
205  b[4] = buf[6];
206  b[5] = buf[7];
207  /*
208  * length_recovery: the unsigned network-ordered sum of lengths of CSRC,
209  * padding, extension and media payload
210  */
211  AV_WB16(b + 6, s->length_recovery);
212  // Payload
213  memcpy(b + 8, buf + 12, s->length_recovery);
214 
215  return 0;
216 }
217 
219  PrompegContext *s = h->priv_data;
220  URLContext *hd;
221  uint8_t *buf = s->rtp_buf; // zero-filled
222  uint8_t *b = fec->bitstring;
223  uint16_t sn;
224  int ret;
225 
226  sn = type == PROMPEG_FEC_COL ? ++s->rtp_col_sn : ++s->rtp_row_sn;
227 
228  // V, P, X, CC
229  buf[0] = 0x80 | (b[0] & 0x3f);
230  // M, PT
231  buf[1] = (b[1] & 0x80) | PROMPEG_RTP_PT;
232  // SN
233  AV_WB16(buf + 2, sn);
234  // TS
235  AV_WB32(buf + 4, fec->ts);
236  // CSRC=0
237  //AV_WB32(buf + 8, 0);
238  // SNBase low bits
239  AV_WB16(buf + 12, fec->sn);
240  // Length recovery
241  buf[14] = b[6];
242  buf[15] = b[7];
243  // E=1, PT recovery
244  buf[16] = 0x80 | b[1];
245  // Mask=0
246  //buf[17] = 0x0;
247  //buf[18] = 0x0;
248  //buf[19] = 0x0;
249  // TS recovery
250  buf[20] = b[2];
251  buf[21] = b[3];
252  buf[22] = b[4];
253  buf[23] = b[5];
254  // X=0, D, type=0, index=0
255  buf[24] = type == PROMPEG_FEC_COL ? 0x0 : 0x40;
256  // offset
257  buf[25] = type == PROMPEG_FEC_COL ? s->l : 0x1;
258  // NA
259  buf[26] = type == PROMPEG_FEC_COL ? s->d : s->l;
260  // SNBase ext bits=0
261  //buf[27] = 0x0;
262  // Payload
263  memcpy(buf + 28, b + 8, s->length_recovery);
264 
265  hd = type == PROMPEG_FEC_COL ? s->fec_col_hd : s->fec_row_hd;
266  ret = ffurl_write(hd, buf, s->rtp_buf_size);
267  return ret;
268 }
269 
270 static int prompeg_open(URLContext *h, const char *uri, int flags) {
271  PrompegContext *s = h->priv_data;
272  AVDictionary *udp_opts = NULL;
273  int rtp_port;
274  char hostname[256];
275  char buf[1024];
276 
277  s->fec_col_hd = NULL;
278  s->fec_row_hd = NULL;
279 
280  if (s->l * s->d > 100) {
281  av_log(h, AV_LOG_ERROR, "L * D must be <= 100\n");
282  return AVERROR(EINVAL);
283  }
284 
285  av_url_split(NULL, 0, NULL, 0, hostname, sizeof (hostname), &rtp_port,
286  NULL, 0, uri);
287 
288  if (rtp_port < 1 || rtp_port > UINT16_MAX - 4) {
289  av_log(h, AV_LOG_ERROR, "Invalid RTP base port %d\n", rtp_port);
290  return AVERROR(EINVAL);
291  }
292 
293  if (s->ttl > 0) {
294  snprintf(buf, sizeof (buf), "%d", s->ttl);
295  av_dict_set(&udp_opts, "ttl", buf, 0);
296  }
297 
298  ff_url_join(buf, sizeof (buf), "udp", NULL, hostname, rtp_port + 2, NULL);
299  if (ffurl_open_whitelist(&s->fec_col_hd, buf, flags, &h->interrupt_callback,
300  &udp_opts, h->protocol_whitelist, h->protocol_blacklist, h) < 0)
301  goto fail;
302  ff_url_join(buf, sizeof (buf), "udp", NULL, hostname, rtp_port + 4, NULL);
303  if (ffurl_open_whitelist(&s->fec_row_hd, buf, flags, &h->interrupt_callback,
304  &udp_opts, h->protocol_whitelist, h->protocol_blacklist, h) < 0)
305  goto fail;
306 
308  s->init = 1;
309 
310  av_dict_free(&udp_opts);
311  av_log(h, AV_LOG_INFO, "ProMPEG CoP#3-R2 FEC L=%d D=%d\n", s->l, s->d);
312  return 0;
313 
314 fail:
317  av_dict_free(&udp_opts);
318  return AVERROR(EIO);
319 }
320 
321 static int prompeg_init(URLContext *h, const uint8_t *buf, int size) {
322  PrompegContext *s = h->priv_data;
323  uint32_t seed;
324  int i;
325 
326  s->fec_arr = NULL;
327  s->rtp_buf = NULL;
328 
329  if (size < 12 || size > UINT16_MAX + 12) {
330  av_log(h, AV_LOG_ERROR, "Invalid RTP packet size\n");
331  return AVERROR_INVALIDDATA;
332  }
333 
334  s->packet_idx = 0;
335  s->packet_idx_max = s->l * s->d;
336  s->packet_size = size;
337  s->length_recovery = size - 12;
338  s->rtp_buf_size = 28 + s->length_recovery; // 12 + 16: RTP + FEC headers
339  s->bitstring_size = 8 + s->length_recovery; // 8: P, X, CC, M, PT, SN, TS
340  s->fec_arr_len = 1 + 2 * s->l; // row + column tmp + column out
341 
342  if (h->flags & AVFMT_FLAG_BITEXACT) {
343  s->rtp_col_sn = 0;
344  s->rtp_row_sn = 0;
345  } else {
346  seed = av_get_random_seed();
347  s->rtp_col_sn = seed & 0x0fff;
348  s->rtp_row_sn = (seed >> 16) & 0x0fff;
349  }
350 
351  s->fec_arr = av_malloc_array(s->fec_arr_len, sizeof (PrompegFec*));
352  if (!s->fec_arr) {
353  goto fail;
354  }
355  for (i = 0; i < s->fec_arr_len; i++) {
356  s->fec_arr[i] = av_malloc(sizeof (PrompegFec));
357  if (!s->fec_arr[i]) {
358  goto fail;
359  }
360  s->fec_arr[i]->bitstring = av_malloc_array(s->bitstring_size, sizeof (uint8_t));
361  if (!s->fec_arr[i]->bitstring) {
362  av_freep(&s->fec_arr[i]);
363  goto fail;
364  }
365  }
366  s->fec_row = *s->fec_arr;
367  s->fec_col = s->fec_arr + 1;
368  s->fec_col_tmp = s->fec_arr + 1 + s->l;
369 
370  s->rtp_buf = av_malloc_array(s->rtp_buf_size, sizeof (uint8_t));
371  if (!s->rtp_buf) {
372  goto fail;
373  }
374  memset(s->rtp_buf, 0, s->rtp_buf_size);
375 
376  s->init = 0;
377  s->first = 1;
378 
379  return 0;
380 
381 fail:
382  av_log(h, AV_LOG_ERROR, "Failed to allocate the FEC buffer\n");
383  return AVERROR(ENOMEM);
384 }
385 
386 static int prompeg_write(URLContext *h, const uint8_t *buf, int size) {
387  PrompegContext *s = h->priv_data;
388  PrompegFec *fec_tmp;
390  int col_idx, col_out_idx, row_idx;
391  int ret, written = 0;
392 
393  if (s->init && ((ret = prompeg_init(h, buf, size)) < 0))
394  goto end;
395 
396  if ((ret = prompeg_create_bitstring(h, buf, size, &bitstring)) < 0)
397  goto end;
398 
399  col_idx = s->packet_idx % s->l;
400  row_idx = s->packet_idx / s->l % s->d;
401 
402  // FEC' (row) send block-aligned, xor
403  if (col_idx == 0) {
404  if (!s->first || s->packet_idx > 0) {
405  if ((ret = prompeg_write_fec(h, s->fec_row, PROMPEG_FEC_ROW)) < 0)
406  goto end;
407  written += ret;
408  }
409  memcpy(s->fec_row->bitstring, bitstring, s->bitstring_size);
410  s->fec_row->sn = AV_RB16(buf + 2);
411  s->fec_row->ts = AV_RB32(buf + 4);
412  } else {
413  xor_fast(s->fec_row->bitstring, bitstring, s->fec_row->bitstring,
414  s->bitstring_size);
415  }
416 
417  // FEC (column) xor
418  if (row_idx == 0) {
419  if (!s->first) {
420  // swap fec_col and fec_col_tmp
421  fec_tmp = s->fec_col[col_idx];
422  s->fec_col[col_idx] = s->fec_col_tmp[col_idx];
423  s->fec_col_tmp[col_idx] = fec_tmp;
424  }
425  memcpy(s->fec_col_tmp[col_idx]->bitstring, bitstring, s->bitstring_size);
426  s->fec_col_tmp[col_idx]->sn = AV_RB16(buf + 2);
427  s->fec_col_tmp[col_idx]->ts = AV_RB32(buf + 4);
428  } else {
429  xor_fast(s->fec_col_tmp[col_idx]->bitstring, bitstring,
430  s->fec_col_tmp[col_idx]->bitstring, s->bitstring_size);
431  }
432 
433  // FEC (column) send block-aligned
434  if (!s->first && s->packet_idx % s->d == 0) {
435  col_out_idx = s->packet_idx / s->d;
436  if ((ret = prompeg_write_fec(h, s->fec_col[col_out_idx], PROMPEG_FEC_COL)) < 0)
437  goto end;
438  written += ret;
439  }
440 
441  if (++s->packet_idx >= s->packet_idx_max) {
442  s->packet_idx = 0;
443  if (s->first)
444  s->first = 0;
445  }
446 
447  ret = written;
448 
449 end:
450  av_free(bitstring);
451  return ret;
452 }
453 
454 static int prompeg_close(URLContext *h) {
455  PrompegContext *s = h->priv_data;
456  int i;
457 
460 
461  if (s->fec_arr) {
462  for (i = 0; i < s->fec_arr_len; i++) {
463  av_free(s->fec_arr[i]->bitstring);
464  av_freep(&s->fec_arr[i]);
465  }
466  av_freep(&s->fec_arr);
467  }
468  av_freep(&s->rtp_buf);
469 
470  return 0;
471 }
472 
474  .name = "prompeg",
475  .url_open = prompeg_open,
476  .url_write = prompeg_write,
477  .url_close = prompeg_close,
478  .priv_data_size = sizeof(PrompegContext),
480  .priv_data_class = &prompeg_class,
481 };
void av_url_split(char *proto, int proto_size, char *authorization, int authorization_size, char *hostname, int hostname_size, int *port_ptr, char *path, int path_size, const char *url)
Split a URL string into components.
Definition: utils.c:4691
#define NULL
Definition: coverity.c:32
uint8_t * bitstring
Definition: prompeg.c:99
const char * s
Definition: avisynth_c.h:768
uint32_t ts
Definition: prompeg.c:98
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int size
int ffurl_open_whitelist(URLContext **puc, const char *filename, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options, const char *whitelist, const char *blacklist, URLContext *parent)
Create an URLContext for accessing to the resource indicated by url, and open it. ...
Definition: avio.c:307
#define URL_PROTOCOL_FLAG_NETWORK
Definition: url.h:34
URLContext * fec_col_hd
Definition: prompeg.c:104
AVOption.
Definition: opt.h:246
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
uint8_t d
Definition: prompeg.c:107
URLContext * fec_row_hd
Definition: prompeg.c:104
int ffurl_write(URLContext *h, const unsigned char *buf, int size)
Write size bytes from buf to the resource accessed by h.
Definition: avio.c:421
AVIOInterruptCB interrupt_callback
Definition: url.h:47
const char * b
Definition: vf_curves.c:113
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
#define PROMPEG_FEC_ROW
Definition: prompeg.c:94
static int prompeg_open(URLContext *h, const char *uri, int flags)
Definition: prompeg.c:270
int packet_idx
Definition: prompeg.c:112
int bitstring_size
Definition: prompeg.c:114
int flags
Definition: url.h:43
int rtp_buf_size
Definition: prompeg.c:115
static const AVClass prompeg_class
Definition: prompeg.c:130
#define AV_WN32A(p, v)
Definition: intreadwrite.h:538
uint16_t rtp_col_sn
Definition: prompeg.c:109
#define AV_RN32A(p)
Definition: intreadwrite.h:526
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
static const AVOption options[]
Definition: prompeg.c:123
uint8_t
#define av_malloc(s)
AVOptions.
#define PROMPEG_FEC_COL
Definition: prompeg.c:93
#define AV_RB32
Definition: intreadwrite.h:130
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
static int flags
Definition: log.c:55
uint8_t * rtp_buf
Definition: prompeg.c:108
#define AVFMT_FLAG_BITEXACT
When muxing, try to avoid writing any random/volatile data to the output.
Definition: avformat.h:1490
#define AV_WB16(p, v)
Definition: intreadwrite.h:405
static int prompeg_init(URLContext *h, const uint8_t *buf, int size)
Definition: prompeg.c:321
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
const char * protocol_whitelist
Definition: url.h:49
#define AV_RB16
Definition: intreadwrite.h:53
#define AVERROR(e)
Definition: error.h:43
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values. ...
Definition: dict.c:203
int packet_size
Definition: prompeg.c:111
const URLProtocol ff_prompeg_protocol
Definition: prompeg.c:473
#define OFFSET(x)
Definition: prompeg.c:120
int fec_arr_len
Definition: prompeg.c:113
#define fail()
Definition: checkasm.h:116
int packet_idx_max
Definition: prompeg.c:112
uint16_t rtp_row_sn
Definition: prompeg.c:109
PrompegFec ** fec_arr
Definition: prompeg.c:105
int n
Definition: avisynth_c.h:684
#define AV_WN64A(p, v)
Definition: intreadwrite.h:542
int ffurl_closep(URLContext **hh)
Close the resource accessed by the URLContext h, and free the memory used by it.
Definition: avio.c:444
int ff_url_join(char *str, int size, const char *proto, const char *authorization, const char *hostname, int port, const char *fmt,...)
Definition: url.c:36
#define AV_LOG_INFO
Standard information.
Definition: log.h:187
const char * protocol_blacklist
Definition: url.h:50
PrompegFec ** fec_col_tmp
Definition: prompeg.c:105
PrompegFec * fec_row
Definition: prompeg.c:105
static unsigned int seed
Definition: videogen.c:78
static int prompeg_write_fec(URLContext *h, PrompegFec *fec, uint8_t type)
Definition: prompeg.c:218
void * buf
Definition: avisynth_c.h:690
Definition: url.h:38
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
Describe the class of an AVClass context structure.
Definition: log.h:67
#define AV_WB32(p, v)
Definition: intreadwrite.h:419
void * priv_data
Definition: url.h:41
cl_device_type type
#define snprintf
Definition: snprintf.h:34
static int prompeg_close(URLContext *h)
Definition: prompeg.c:454
misc parsing utilities
const char * name
Definition: url.h:55
PrompegFec ** fec_col
Definition: prompeg.c:105
static int prompeg_create_bitstring(URLContext *h, const uint8_t *buf, int size, uint8_t **bitstring)
Definition: prompeg.c:177
uint16_t length_recovery
Definition: prompeg.c:110
Main libavformat public API header.
static int prompeg_write(URLContext *h, const uint8_t *buf, int size)
Definition: prompeg.c:386
#define PROMPEG_RTP_PT
Definition: prompeg.c:92
#define av_free(p)
uint16_t sn
Definition: prompeg.c:97
#define E
Definition: prompeg.c:121
int max_packet_size
if non zero, the stream is packetized with this max packet size
Definition: url.h:44
FILE * out
Definition: movenc.c:54
#define av_freep(p)
unbuffered private I/O API
uint32_t av_get_random_seed(void)
Get a seed to use in conjunction with random functions.
Definition: random_seed.c:120
#define av_malloc_array(a, b)
static void xor_fast(const uint8_t *in1, const uint8_t *in2, uint8_t *out, int size)
Definition: prompeg.c:137
#define AV_RN64A(p)
Definition: intreadwrite.h:530
uint8_t l
Definition: prompeg.c:107