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smoothstreamingenc.c
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1 /*
2  * Live smooth streaming fragmenter
3  * Copyright (c) 2012 Martin Storsjo
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 #include "config.h"
23 #include <float.h>
24 #if HAVE_UNISTD_H
25 #include <unistd.h>
26 #endif
27 
28 #include "avformat.h"
29 #include "internal.h"
30 #include "os_support.h"
31 #include "avc.h"
32 #include "url.h"
33 #include "isom.h"
34 
35 #include "libavutil/opt.h"
36 #include "libavutil/avstring.h"
37 #include "libavutil/mathematics.h"
38 #include "libavutil/intreadwrite.h"
39 
40 typedef struct {
41  char file[1024];
42  char infofile[1024];
43  int64_t start_time, duration;
44  int n;
45  int64_t start_pos, size;
46 } Fragment;
47 
48 typedef struct {
49  AVFormatContext *ctx;
50  int ctx_inited;
51  char dirname[1024];
52  uint8_t iobuf[32768];
53  URLContext *out; // Current output stream where all output is written
54  URLContext *out2; // Auxiliary output stream where all output is also written
55  URLContext *tail_out; // The actual main output stream, if we're currently seeked back to write elsewhere
56  int64_t tail_pos, cur_pos, cur_start_pos;
57  int packets_written;
58  const char *stream_type_tag;
59  int nb_fragments, fragments_size, fragment_index;
60  Fragment **fragments;
61 
62  const char *fourcc;
63  char *private_str;
64  int packet_size;
65  int audio_tag;
66 } OutputStream;
67 
68 typedef struct {
69  const AVClass *class; /* Class for private options. */
70  int window_size;
71  int extra_window_size;
72  int lookahead_count;
73  int min_frag_duration;
74  int remove_at_exit;
75  OutputStream *streams;
76  int has_video, has_audio;
77  int nb_fragments;
78 } SmoothStreamingContext;
79 
80 static int ism_write(void *opaque, uint8_t *buf, int buf_size)
81 {
82  OutputStream *os = opaque;
83  if (os->out)
84  ffurl_write(os->out, buf, buf_size);
85  if (os->out2)
86  ffurl_write(os->out2, buf, buf_size);
87  os->cur_pos += buf_size;
88  if (os->cur_pos >= os->tail_pos)
89  os->tail_pos = os->cur_pos;
90  return buf_size;
91 }
92 
93 static int64_t ism_seek(void *opaque, int64_t offset, int whence)
94 {
95  OutputStream *os = opaque;
96  int i;
97  if (whence != SEEK_SET)
98  return AVERROR(ENOSYS);
99  if (os->tail_out) {
100  if (os->out) {
101  ffurl_close(os->out);
102  }
103  if (os->out2) {
104  ffurl_close(os->out2);
105  }
106  os->out = os->tail_out;
107  os->out2 = NULL;
108  os->tail_out = NULL;
109  }
110  if (offset >= os->cur_start_pos) {
111  if (os->out)
112  ffurl_seek(os->out, offset - os->cur_start_pos, SEEK_SET);
113  os->cur_pos = offset;
114  return offset;
115  }
116  for (i = os->nb_fragments - 1; i >= 0; i--) {
117  Fragment *frag = os->fragments[i];
118  if (offset >= frag->start_pos && offset < frag->start_pos + frag->size) {
119  int ret;
120  AVDictionary *opts = NULL;
121  os->tail_out = os->out;
122  av_dict_set(&opts, "truncate", "0", 0);
123  ret = ffurl_open(&os->out, frag->file, AVIO_FLAG_READ_WRITE, &os->ctx->interrupt_callback, &opts);
124  av_dict_free(&opts);
125  if (ret < 0) {
126  os->out = os->tail_out;
127  os->tail_out = NULL;
128  return ret;
129  }
130  av_dict_set(&opts, "truncate", "0", 0);
131  ffurl_open(&os->out2, frag->infofile, AVIO_FLAG_READ_WRITE, &os->ctx->interrupt_callback, &opts);
132  av_dict_free(&opts);
133  ffurl_seek(os->out, offset - frag->start_pos, SEEK_SET);
134  if (os->out2)
135  ffurl_seek(os->out2, offset - frag->start_pos, SEEK_SET);
136  os->cur_pos = offset;
137  return offset;
138  }
139  }
140  return AVERROR(EIO);
141 }
142 
143 static void get_private_data(OutputStream *os)
144 {
145  AVCodecContext *codec = os->ctx->streams[0]->codec;
146  uint8_t *ptr = codec->extradata;
147  int size = codec->extradata_size;
148  int i;
149  if (codec->codec_id == AV_CODEC_ID_H264) {
150  ff_avc_write_annexb_extradata(ptr, &ptr, &size);
151  if (!ptr)
152  ptr = codec->extradata;
153  }
154  if (!ptr)
155  return;
156  os->private_str = av_mallocz(2*size + 1);
157  if (!os->private_str)
158  goto fail;
159  for (i = 0; i < size; i++)
160  snprintf(&os->private_str[2*i], 3, "%02x", ptr[i]);
161 fail:
162  if (ptr != codec->extradata)
163  av_free(ptr);
164 }
165 
166 static void ism_free(AVFormatContext *s)
167 {
168  SmoothStreamingContext *c = s->priv_data;
169  int i, j;
170  if (!c->streams)
171  return;
172  for (i = 0; i < s->nb_streams; i++) {
173  OutputStream *os = &c->streams[i];
174  ffurl_close(os->out);
175  ffurl_close(os->out2);
176  ffurl_close(os->tail_out);
177  os->out = os->out2 = os->tail_out = NULL;
178  if (os->ctx && os->ctx_inited)
179  av_write_trailer(os->ctx);
180  if (os->ctx && os->ctx->pb)
181  av_free(os->ctx->pb);
182  if (os->ctx)
183  avformat_free_context(os->ctx);
184  av_free(os->private_str);
185  for (j = 0; j < os->nb_fragments; j++)
186  av_free(os->fragments[j]);
187  av_free(os->fragments);
188  }
189  av_freep(&c->streams);
190 }
191 
192 static void output_chunk_list(OutputStream *os, AVIOContext *out, int final, int skip, int window_size)
193 {
194  int removed = 0, i, start = 0;
195  if (os->nb_fragments <= 0)
196  return;
197  if (os->fragments[0]->n > 0)
198  removed = 1;
199  if (final)
200  skip = 0;
201  if (window_size)
202  start = FFMAX(os->nb_fragments - skip - window_size, 0);
203  for (i = start; i < os->nb_fragments - skip; i++) {
204  Fragment *frag = os->fragments[i];
205  if (!final || removed)
206  avio_printf(out, "<c t=\"%"PRIu64"\" d=\"%"PRIu64"\" />\n", frag->start_time, frag->duration);
207  else
208  avio_printf(out, "<c n=\"%d\" d=\"%"PRIu64"\" />\n", frag->n, frag->duration);
209  }
210 }
211 
212 static int write_manifest(AVFormatContext *s, int final)
213 {
214  SmoothStreamingContext *c = s->priv_data;
215  AVIOContext *out;
216  char filename[1024], temp_filename[1024];
217  int ret, i, video_chunks = 0, audio_chunks = 0, video_streams = 0, audio_streams = 0;
218  int64_t duration = 0;
219 
220  snprintf(filename, sizeof(filename), "%s/Manifest", s->filename);
221  snprintf(temp_filename, sizeof(temp_filename), "%s/Manifest.tmp", s->filename);
222  ret = avio_open2(&out, temp_filename, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL);
223  if (ret < 0) {
224  av_log(s, AV_LOG_ERROR, "Unable to open %s for writing\n", temp_filename);
225  return ret;
226  }
227  avio_printf(out, "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n");
228  for (i = 0; i < s->nb_streams; i++) {
229  OutputStream *os = &c->streams[i];
230  if (os->nb_fragments > 0) {
231  Fragment *last = os->fragments[os->nb_fragments - 1];
232  duration = last->start_time + last->duration;
233  }
234  if (s->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
235  video_chunks = os->nb_fragments;
236  video_streams++;
237  } else {
238  audio_chunks = os->nb_fragments;
239  audio_streams++;
240  }
241  }
242  if (!final) {
243  duration = 0;
244  video_chunks = audio_chunks = 0;
245  }
246  if (c->window_size) {
247  video_chunks = FFMIN(video_chunks, c->window_size);
248  audio_chunks = FFMIN(audio_chunks, c->window_size);
249  }
250  avio_printf(out, "<SmoothStreamingMedia MajorVersion=\"2\" MinorVersion=\"0\" Duration=\"%"PRIu64"\"", duration);
251  if (!final)
252  avio_printf(out, " IsLive=\"true\" LookAheadFragmentCount=\"%d\" DVRWindowLength=\"0\"", c->lookahead_count);
253  avio_printf(out, ">\n");
254  if (c->has_video) {
255  int last = -1, index = 0;
256  avio_printf(out, "<StreamIndex Type=\"video\" QualityLevels=\"%d\" Chunks=\"%d\" Url=\"QualityLevels({bitrate})/Fragments(video={start time})\">\n", video_streams, video_chunks);
257  for (i = 0; i < s->nb_streams; i++) {
258  OutputStream *os = &c->streams[i];
259  if (s->streams[i]->codec->codec_type != AVMEDIA_TYPE_VIDEO)
260  continue;
261  last = i;
262  avio_printf(out, "<QualityLevel Index=\"%d\" Bitrate=\"%d\" FourCC=\"%s\" MaxWidth=\"%d\" MaxHeight=\"%d\" CodecPrivateData=\"%s\" />\n", index, s->streams[i]->codec->bit_rate, os->fourcc, s->streams[i]->codec->width, s->streams[i]->codec->height, os->private_str);
263  index++;
264  }
265  output_chunk_list(&c->streams[last], out, final, c->lookahead_count, c->window_size);
266  avio_printf(out, "</StreamIndex>\n");
267  }
268  if (c->has_audio) {
269  int last = -1, index = 0;
270  avio_printf(out, "<StreamIndex Type=\"audio\" QualityLevels=\"%d\" Chunks=\"%d\" Url=\"QualityLevels({bitrate})/Fragments(audio={start time})\">\n", audio_streams, audio_chunks);
271  for (i = 0; i < s->nb_streams; i++) {
272  OutputStream *os = &c->streams[i];
273  if (s->streams[i]->codec->codec_type != AVMEDIA_TYPE_AUDIO)
274  continue;
275  last = i;
276  avio_printf(out, "<QualityLevel Index=\"%d\" Bitrate=\"%d\" FourCC=\"%s\" SamplingRate=\"%d\" Channels=\"%d\" BitsPerSample=\"16\" PacketSize=\"%d\" AudioTag=\"%d\" CodecPrivateData=\"%s\" />\n", index, s->streams[i]->codec->bit_rate, os->fourcc, s->streams[i]->codec->sample_rate, s->streams[i]->codec->channels, os->packet_size, os->audio_tag, os->private_str);
277  index++;
278  }
279  output_chunk_list(&c->streams[last], out, final, c->lookahead_count, c->window_size);
280  avio_printf(out, "</StreamIndex>\n");
281  }
282  avio_printf(out, "</SmoothStreamingMedia>\n");
283  avio_flush(out);
284  avio_close(out);
285  rename(temp_filename, filename);
286  return 0;
287 }
288 
289 static int ism_write_header(AVFormatContext *s)
290 {
291  SmoothStreamingContext *c = s->priv_data;
292  int ret = 0, i;
293  AVOutputFormat *oformat;
294 
295  if (mkdir(s->filename, 0777) < 0) {
296  av_log(s, AV_LOG_ERROR, "mkdir failed\n");
297  ret = AVERROR(errno);
298  goto fail;
299  }
300 
301  oformat = av_guess_format("ismv", NULL, NULL);
302  if (!oformat) {
303  ret = AVERROR_MUXER_NOT_FOUND;
304  goto fail;
305  }
306 
307  c->streams = av_mallocz_array(s->nb_streams, sizeof(*c->streams));
308  if (!c->streams) {
309  ret = AVERROR(ENOMEM);
310  goto fail;
311  }
312 
313  for (i = 0; i < s->nb_streams; i++) {
314  OutputStream *os = &c->streams[i];
315  AVFormatContext *ctx;
316  AVStream *st;
317  AVDictionary *opts = NULL;
318  char buf[10];
319 
320  if (!s->streams[i]->codec->bit_rate) {
321  av_log(s, AV_LOG_ERROR, "No bit rate set for stream %d\n", i);
322  ret = AVERROR(EINVAL);
323  goto fail;
324  }
325  snprintf(os->dirname, sizeof(os->dirname), "%s/QualityLevels(%d)", s->filename, s->streams[i]->codec->bit_rate);
326  if (mkdir(os->dirname, 0777) < 0) {
327  ret = AVERROR(errno);
328  av_log(s, AV_LOG_ERROR, "mkdir failed\n");
329  goto fail;
330  }
331 
332  ctx = avformat_alloc_context();
333  if (!ctx) {
334  ret = AVERROR(ENOMEM);
335  goto fail;
336  }
337  os->ctx = ctx;
338  ctx->oformat = oformat;
339  ctx->interrupt_callback = s->interrupt_callback;
340 
341  if (!(st = avformat_new_stream(ctx, NULL))) {
342  ret = AVERROR(ENOMEM);
343  goto fail;
344  }
345  avcodec_copy_context(st->codec, s->streams[i]->codec);
346  st->sample_aspect_ratio = s->streams[i]->sample_aspect_ratio;
347 
348  ctx->pb = avio_alloc_context(os->iobuf, sizeof(os->iobuf), AVIO_FLAG_WRITE, os, NULL, ism_write, ism_seek);
349  if (!ctx->pb) {
350  ret = AVERROR(ENOMEM);
351  goto fail;
352  }
353 
354  snprintf(buf, sizeof(buf), "%d", c->lookahead_count);
355  av_dict_set(&opts, "ism_lookahead", buf, 0);
356  av_dict_set(&opts, "movflags", "frag_custom", 0);
357  if ((ret = avformat_write_header(ctx, &opts)) < 0) {
358  goto fail;
359  }
360  os->ctx_inited = 1;
361  avio_flush(ctx->pb);
362  av_dict_free(&opts);
363  s->streams[i]->time_base = st->time_base;
364  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
365  c->has_video = 1;
366  os->stream_type_tag = "video";
367  if (st->codec->codec_id == AV_CODEC_ID_H264) {
368  os->fourcc = "H264";
369  } else if (st->codec->codec_id == AV_CODEC_ID_VC1) {
370  os->fourcc = "WVC1";
371  } else {
372  av_log(s, AV_LOG_ERROR, "Unsupported video codec\n");
373  ret = AVERROR(EINVAL);
374  goto fail;
375  }
376  } else {
377  c->has_audio = 1;
378  os->stream_type_tag = "audio";
379  if (st->codec->codec_id == AV_CODEC_ID_AAC) {
380  os->fourcc = "AACL";
381  os->audio_tag = 0xff;
382  } else if (st->codec->codec_id == AV_CODEC_ID_WMAPRO) {
383  os->fourcc = "WMAP";
384  os->audio_tag = 0x0162;
385  } else {
386  av_log(s, AV_LOG_ERROR, "Unsupported audio codec\n");
387  ret = AVERROR(EINVAL);
388  goto fail;
389  }
390  os->packet_size = st->codec->block_align ? st->codec->block_align : 4;
391  }
392  get_private_data(os);
393  }
394 
395  if (!c->has_video && c->min_frag_duration <= 0) {
396  av_log(s, AV_LOG_WARNING, "no video stream and no min frag duration set\n");
397  ret = AVERROR(EINVAL);
398  }
399  ret = write_manifest(s, 0);
400 
401 fail:
402  if (ret)
403  ism_free(s);
404  return ret;
405 }
406 
407 static int parse_fragment(AVFormatContext *s, const char *filename, int64_t *start_ts, int64_t *duration, int64_t *moof_size, int64_t size)
408 {
409  AVIOContext *in;
410  int ret;
411  uint32_t len;
412  if ((ret = avio_open2(&in, filename, AVIO_FLAG_READ, &s->interrupt_callback, NULL)) < 0)
413  return ret;
414  ret = AVERROR(EIO);
415  *moof_size = avio_rb32(in);
416  if (*moof_size < 8 || *moof_size > size)
417  goto fail;
418  if (avio_rl32(in) != MKTAG('m','o','o','f'))
419  goto fail;
420  len = avio_rb32(in);
421  if (len > *moof_size)
422  goto fail;
423  if (avio_rl32(in) != MKTAG('m','f','h','d'))
424  goto fail;
425  avio_seek(in, len - 8, SEEK_CUR);
426  avio_rb32(in); /* traf size */
427  if (avio_rl32(in) != MKTAG('t','r','a','f'))
428  goto fail;
429  while (avio_tell(in) < *moof_size) {
430  uint32_t len = avio_rb32(in);
431  uint32_t tag = avio_rl32(in);
432  int64_t end = avio_tell(in) + len - 8;
433  if (len < 8 || len >= *moof_size)
434  goto fail;
435  if (tag == MKTAG('u','u','i','d')) {
436  static const uint8_t tfxd[] = {
437  0x6d, 0x1d, 0x9b, 0x05, 0x42, 0xd5, 0x44, 0xe6,
438  0x80, 0xe2, 0x14, 0x1d, 0xaf, 0xf7, 0x57, 0xb2
439  };
440  uint8_t uuid[16];
441  avio_read(in, uuid, 16);
442  if (!memcmp(uuid, tfxd, 16) && len >= 8 + 16 + 4 + 16) {
443  avio_seek(in, 4, SEEK_CUR);
444  *start_ts = avio_rb64(in);
445  *duration = avio_rb64(in);
446  ret = 0;
447  break;
448  }
449  }
450  avio_seek(in, end, SEEK_SET);
451  }
452 fail:
453  avio_close(in);
454  return ret;
455 }
456 
457 static int add_fragment(OutputStream *os, const char *file, const char *infofile, int64_t start_time, int64_t duration, int64_t start_pos, int64_t size)
458 {
459  int err;
460  Fragment *frag;
461  if (os->nb_fragments >= os->fragments_size) {
462  os->fragments_size = (os->fragments_size + 1) * 2;
463  if ((err = av_reallocp(&os->fragments, sizeof(*os->fragments) *
464  os->fragments_size)) < 0) {
465  os->fragments_size = 0;
466  os->nb_fragments = 0;
467  return err;
468  }
469  }
470  frag = av_mallocz(sizeof(*frag));
471  if (!frag)
472  return AVERROR(ENOMEM);
473  av_strlcpy(frag->file, file, sizeof(frag->file));
474  av_strlcpy(frag->infofile, infofile, sizeof(frag->infofile));
475  frag->start_time = start_time;
476  frag->duration = duration;
477  frag->start_pos = start_pos;
478  frag->size = size;
479  frag->n = os->fragment_index;
480  os->fragments[os->nb_fragments++] = frag;
481  os->fragment_index++;
482  return 0;
483 }
484 
485 static int copy_moof(AVFormatContext *s, const char* infile, const char *outfile, int64_t size)
486 {
487  AVIOContext *in, *out;
488  int ret = 0;
489  if ((ret = avio_open2(&in, infile, AVIO_FLAG_READ, &s->interrupt_callback, NULL)) < 0)
490  return ret;
491  if ((ret = avio_open2(&out, outfile, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL)) < 0) {
492  avio_close(in);
493  return ret;
494  }
495  while (size > 0) {
496  uint8_t buf[8192];
497  int n = FFMIN(size, sizeof(buf));
498  n = avio_read(in, buf, n);
499  if (n <= 0) {
500  ret = AVERROR(EIO);
501  break;
502  }
503  avio_write(out, buf, n);
504  size -= n;
505  }
506  avio_flush(out);
507  avio_close(out);
508  avio_close(in);
509  return ret;
510 }
511 
512 static int ism_flush(AVFormatContext *s, int final)
513 {
514  SmoothStreamingContext *c = s->priv_data;
515  int i, ret = 0;
516 
517  for (i = 0; i < s->nb_streams; i++) {
518  OutputStream *os = &c->streams[i];
519  char filename[1024], target_filename[1024], header_filename[1024];
520  int64_t start_pos = os->tail_pos, size;
521  int64_t start_ts, duration, moof_size;
522  if (!os->packets_written)
523  continue;
524 
525  snprintf(filename, sizeof(filename), "%s/temp", os->dirname);
526  ret = ffurl_open(&os->out, filename, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL);
527  if (ret < 0)
528  break;
529  os->cur_start_pos = os->tail_pos;
530  av_write_frame(os->ctx, NULL);
531  avio_flush(os->ctx->pb);
532  os->packets_written = 0;
533  if (!os->out || os->tail_out)
534  return AVERROR(EIO);
535 
536  ffurl_close(os->out);
537  os->out = NULL;
538  size = os->tail_pos - start_pos;
539  if ((ret = parse_fragment(s, filename, &start_ts, &duration, &moof_size, size)) < 0)
540  break;
541  snprintf(header_filename, sizeof(header_filename), "%s/FragmentInfo(%s=%"PRIu64")", os->dirname, os->stream_type_tag, start_ts);
542  snprintf(target_filename, sizeof(target_filename), "%s/Fragments(%s=%"PRIu64")", os->dirname, os->stream_type_tag, start_ts);
543  copy_moof(s, filename, header_filename, moof_size);
544  rename(filename, target_filename);
545  add_fragment(os, target_filename, header_filename, start_ts, duration, start_pos, size);
546  }
547 
548  if (c->window_size || (final && c->remove_at_exit)) {
549  for (i = 0; i < s->nb_streams; i++) {
550  OutputStream *os = &c->streams[i];
551  int j;
552  int remove = os->nb_fragments - c->window_size - c->extra_window_size - c->lookahead_count;
553  if (final && c->remove_at_exit)
554  remove = os->nb_fragments;
555  if (remove > 0) {
556  for (j = 0; j < remove; j++) {
557  unlink(os->fragments[j]->file);
558  unlink(os->fragments[j]->infofile);
559  av_free(os->fragments[j]);
560  }
561  os->nb_fragments -= remove;
562  memmove(os->fragments, os->fragments + remove, os->nb_fragments * sizeof(*os->fragments));
563  }
564  if (final && c->remove_at_exit)
565  rmdir(os->dirname);
566  }
567  }
568 
569  if (ret >= 0)
570  ret = write_manifest(s, final);
571  return ret;
572 }
573 
574 static int ism_write_packet(AVFormatContext *s, AVPacket *pkt)
575 {
576  SmoothStreamingContext *c = s->priv_data;
577  AVStream *st = s->streams[pkt->stream_index];
578  OutputStream *os = &c->streams[pkt->stream_index];
579  int64_t end_dts = (c->nb_fragments + 1LL) * c->min_frag_duration;
580  int ret;
581 
582  if (st->first_dts == AV_NOPTS_VALUE)
583  st->first_dts = pkt->dts;
584 
585  if ((!c->has_video || st->codec->codec_type == AVMEDIA_TYPE_VIDEO) &&
586  av_compare_ts(pkt->dts - st->first_dts, st->time_base,
587  end_dts, AV_TIME_BASE_Q) >= 0 &&
588  pkt->flags & AV_PKT_FLAG_KEY && os->packets_written) {
589 
590  if ((ret = ism_flush(s, 0)) < 0)
591  return ret;
592  c->nb_fragments++;
593  }
594 
595  os->packets_written++;
596  return ff_write_chained(os->ctx, 0, pkt, s, 0);
597 }
598 
599 static int ism_write_trailer(AVFormatContext *s)
600 {
601  SmoothStreamingContext *c = s->priv_data;
602  ism_flush(s, 1);
603 
604  if (c->remove_at_exit) {
605  char filename[1024];
606  snprintf(filename, sizeof(filename), "%s/Manifest", s->filename);
607  unlink(filename);
608  rmdir(s->filename);
609  }
610 
611  ism_free(s);
612  return 0;
613 }
614 
615 #define OFFSET(x) offsetof(SmoothStreamingContext, x)
616 #define E AV_OPT_FLAG_ENCODING_PARAM
617 static const AVOption options[] = {
618  { "window_size", "number of fragments kept in the manifest", OFFSET(window_size), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, E },
619  { "extra_window_size", "number of fragments kept outside of the manifest before removing from disk", OFFSET(extra_window_size), AV_OPT_TYPE_INT, { .i64 = 5 }, 0, INT_MAX, E },
620  { "lookahead_count", "number of lookahead fragments", OFFSET(lookahead_count), AV_OPT_TYPE_INT, { .i64 = 2 }, 0, INT_MAX, E },
621  { "min_frag_duration", "minimum fragment duration (in microseconds)", OFFSET(min_frag_duration), AV_OPT_TYPE_INT64, { .i64 = 5000000 }, 0, INT_MAX, E },
622  { "remove_at_exit", "remove all fragments when finished", OFFSET(remove_at_exit), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, E },
623  { NULL },
624 };
625 
626 static const AVClass ism_class = {
627  .class_name = "smooth streaming muxer",
628  .item_name = av_default_item_name,
629  .option = options,
630  .version = LIBAVUTIL_VERSION_INT,
631 };
632 
633 
634 AVOutputFormat ff_smoothstreaming_muxer = {
635  .name = "smoothstreaming",
636  .long_name = NULL_IF_CONFIG_SMALL("Smooth Streaming Muxer"),
637  .priv_data_size = sizeof(SmoothStreamingContext),
638  .audio_codec = AV_CODEC_ID_AAC,
639  .video_codec = AV_CODEC_ID_H264,
640  .flags = AVFMT_GLOBALHEADER | AVFMT_NOFILE,
641  .write_header = ism_write_header,
642  .write_packet = ism_write_packet,
643  .write_trailer = ism_write_trailer,
644  .codec_tag = (const AVCodecTag* const []){ ff_mp4_obj_type, 0 },
645  .priv_class = &ism_class,
646 };
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