File: hdsenc.c

package info (click to toggle)
ffmpeg 7%3A3.2.5-1~bpo8%2B1
  • links: PTS, VCS
  • area: main
  • in suites: jessie-backports
  • size: 72,224 kB
  • sloc: ansic: 927,948; asm: 77,498; sh: 7,731; makefile: 3,652; cpp: 1,504; objc: 1,069; perl: 986; python: 49
file content (594 lines) | stat: -rw-r--r-- 19,887 bytes parent folder | download | duplicates (5)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
/*
 * Live HDS fragmenter
 * Copyright (c) 2013 Martin Storsjo
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "config.h"
#include <float.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif

#include "avformat.h"
#include "avio_internal.h"
#include "internal.h"
#include "os_support.h"

#include "libavutil/avstring.h"
#include "libavutil/base64.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/mathematics.h"
#include "libavutil/opt.h"

typedef struct Fragment {
    char file[1024];
    int64_t start_time, duration;
    int n;
} Fragment;

typedef struct OutputStream {
    int bitrate;
    int first_stream;
    AVFormatContext *ctx;
    int ctx_inited;
    uint8_t iobuf[32768];
    char temp_filename[1024];
    int64_t frag_start_ts, last_ts;
    AVIOContext *out;
    int packets_written;
    int nb_fragments, fragments_size, fragment_index;
    Fragment **fragments;

    int has_audio, has_video;

    uint8_t *metadata;
    int metadata_size;

    uint8_t *extra_packets[2];
    int extra_packet_sizes[2];
    int nb_extra_packets;
} OutputStream;

typedef struct HDSContext {
    const AVClass *class;  /* Class for private options. */
    int window_size;
    int extra_window_size;
    int min_frag_duration;
    int remove_at_exit;

    OutputStream *streams;
    int nb_streams;
} HDSContext;

static int parse_header(OutputStream *os, const uint8_t *buf, int buf_size)
{
    if (buf_size < 13)
        return AVERROR_INVALIDDATA;
    if (memcmp(buf, "FLV", 3))
        return AVERROR_INVALIDDATA;
    buf      += 13;
    buf_size -= 13;
    while (buf_size >= 11 + 4) {
        int type = buf[0];
        int size = AV_RB24(&buf[1]) + 11 + 4;
        if (size > buf_size)
            return AVERROR_INVALIDDATA;
        if (type == 8 || type == 9) {
            if (os->nb_extra_packets >= FF_ARRAY_ELEMS(os->extra_packets))
                return AVERROR_INVALIDDATA;
            os->extra_packet_sizes[os->nb_extra_packets] = size;
            os->extra_packets[os->nb_extra_packets] = av_malloc(size);
            if (!os->extra_packets[os->nb_extra_packets])
                return AVERROR(ENOMEM);
            memcpy(os->extra_packets[os->nb_extra_packets], buf, size);
            os->nb_extra_packets++;
        } else if (type == 0x12) {
            if (os->metadata)
                return AVERROR_INVALIDDATA;
            os->metadata_size = size - 11 - 4;
            os->metadata      = av_malloc(os->metadata_size);
            if (!os->metadata)
                return AVERROR(ENOMEM);
            memcpy(os->metadata, buf + 11, os->metadata_size);
        }
        buf      += size;
        buf_size -= size;
    }
    if (!os->metadata)
        return AVERROR_INVALIDDATA;
    return 0;
}

static int hds_write(void *opaque, uint8_t *buf, int buf_size)
{
    OutputStream *os = opaque;
    if (os->out) {
        avio_write(os->out, buf, buf_size);
    } else {
        if (!os->metadata_size) {
            int ret;
            // Assuming the IO buffer is large enough to fit the
            // FLV header and all metadata and extradata packets
            if ((ret = parse_header(os, buf, buf_size)) < 0)
                return ret;
        }
    }
    return buf_size;
}

static void hds_free(AVFormatContext *s)
{
    HDSContext *c = s->priv_data;
    int i, j;
    if (!c->streams)
        return;
    for (i = 0; i < s->nb_streams; i++) {
        OutputStream *os = &c->streams[i];
        if (os->out)
            ff_format_io_close(s, &os->out);
        if (os->ctx && os->ctx_inited)
            av_write_trailer(os->ctx);
        if (os->ctx)
            av_freep(&os->ctx->pb);
        if (os->ctx)
            avformat_free_context(os->ctx);
        av_freep(&os->metadata);
        for (j = 0; j < os->nb_extra_packets; j++)
            av_freep(&os->extra_packets[j]);
        for (j = 0; j < os->nb_fragments; j++)
            av_freep(&os->fragments[j]);
        av_freep(&os->fragments);
    }
    av_freep(&c->streams);
}

static int write_manifest(AVFormatContext *s, int final)
{
    HDSContext *c = s->priv_data;
    AVIOContext *out;
    char filename[1024], temp_filename[1024];
    int ret, i;
    double duration = 0;

    if (c->nb_streams > 0)
        duration = c->streams[0].last_ts * av_q2d(s->streams[0]->time_base);

    snprintf(filename, sizeof(filename), "%s/index.f4m", s->filename);
    snprintf(temp_filename, sizeof(temp_filename), "%s/index.f4m.tmp", s->filename);
    ret = s->io_open(s, &out, temp_filename, AVIO_FLAG_WRITE, NULL);
    if (ret < 0) {
        av_log(s, AV_LOG_ERROR, "Unable to open %s for writing\n", temp_filename);
        return ret;
    }
    avio_printf(out, "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n");
    avio_printf(out, "<manifest xmlns=\"http://ns.adobe.com/f4m/1.0\">\n");
    avio_printf(out, "\t<id>%s</id>\n", av_basename(s->filename));
    avio_printf(out, "\t<streamType>%s</streamType>\n",
                     final ? "recorded" : "live");
    avio_printf(out, "\t<deliveryType>streaming</deliveryType>\n");
    if (final)
        avio_printf(out, "\t<duration>%f</duration>\n", duration);
    for (i = 0; i < c->nb_streams; i++) {
        OutputStream *os = &c->streams[i];
        int b64_size = AV_BASE64_SIZE(os->metadata_size);
        char *base64 = av_malloc(b64_size);
        if (!base64) {
            ff_format_io_close(s, &out);
            return AVERROR(ENOMEM);
        }
        av_base64_encode(base64, b64_size, os->metadata, os->metadata_size);

        avio_printf(out, "\t<bootstrapInfo profile=\"named\" url=\"stream%d.abst\" id=\"bootstrap%d\" />\n", i, i);
        avio_printf(out, "\t<media bitrate=\"%d\" url=\"stream%d\" bootstrapInfoId=\"bootstrap%d\">\n", os->bitrate/1000, i, i);
        avio_printf(out, "\t\t<metadata>%s</metadata>\n", base64);
        avio_printf(out, "\t</media>\n");
        av_free(base64);
    }
    avio_printf(out, "</manifest>\n");
    avio_flush(out);
    ff_format_io_close(s, &out);
    return ff_rename(temp_filename, filename, s);
}

static void update_size(AVIOContext *out, int64_t pos)
{
    int64_t end = avio_tell(out);
    avio_seek(out, pos, SEEK_SET);
    avio_wb32(out, end - pos);
    avio_seek(out, end, SEEK_SET);
}

/* Note, the .abst files need to be served with the "binary/octet"
 * mime type, otherwise at least the OSMF player can easily fail
 * with "stream not found" when polling for the next fragment. */
static int write_abst(AVFormatContext *s, OutputStream *os, int final)
{
    HDSContext *c = s->priv_data;
    AVIOContext *out;
    char filename[1024], temp_filename[1024];
    int i, ret;
    int64_t asrt_pos, afrt_pos;
    int start = 0, fragments;
    int index = s->streams[os->first_stream]->id;
    int64_t cur_media_time = 0;
    if (c->window_size)
        start = FFMAX(os->nb_fragments - c->window_size, 0);
    fragments = os->nb_fragments - start;
    if (final)
        cur_media_time = os->last_ts;
    else if (os->nb_fragments)
        cur_media_time = os->fragments[os->nb_fragments - 1]->start_time;

    snprintf(filename, sizeof(filename),
             "%s/stream%d.abst", s->filename, index);
    snprintf(temp_filename, sizeof(temp_filename),
             "%s/stream%d.abst.tmp", s->filename, index);
    ret = s->io_open(s, &out, temp_filename, AVIO_FLAG_WRITE, NULL);
    if (ret < 0) {
        av_log(s, AV_LOG_ERROR, "Unable to open %s for writing\n", temp_filename);
        return ret;
    }
    avio_wb32(out, 0); // abst size
    avio_wl32(out, MKTAG('a','b','s','t'));
    avio_wb32(out, 0); // version + flags
    avio_wb32(out, os->fragment_index - 1); // BootstrapinfoVersion
    avio_w8(out, final ? 0 : 0x20); // profile, live, update
    avio_wb32(out, 1000); // timescale
    avio_wb64(out, cur_media_time);
    avio_wb64(out, 0); // SmpteTimeCodeOffset
    avio_w8(out, 0); // MovieIdentifer (null string)
    avio_w8(out, 0); // ServerEntryCount
    avio_w8(out, 0); // QualityEntryCount
    avio_w8(out, 0); // DrmData (null string)
    avio_w8(out, 0); // MetaData (null string)
    avio_w8(out, 1); // SegmentRunTableCount
    asrt_pos = avio_tell(out);
    avio_wb32(out, 0); // asrt size
    avio_wl32(out, MKTAG('a','s','r','t'));
    avio_wb32(out, 0); // version + flags
    avio_w8(out, 0); // QualityEntryCount
    avio_wb32(out, 1); // SegmentRunEntryCount
    avio_wb32(out, 1); // FirstSegment
    avio_wb32(out, final ? (os->fragment_index - 1) : 0xffffffff); // FragmentsPerSegment
    update_size(out, asrt_pos);
    avio_w8(out, 1); // FragmentRunTableCount
    afrt_pos = avio_tell(out);
    avio_wb32(out, 0); // afrt size
    avio_wl32(out, MKTAG('a','f','r','t'));
    avio_wb32(out, 0); // version + flags
    avio_wb32(out, 1000); // timescale
    avio_w8(out, 0); // QualityEntryCount
    avio_wb32(out, fragments); // FragmentRunEntryCount
    for (i = start; i < os->nb_fragments; i++) {
        avio_wb32(out, os->fragments[i]->n);
        avio_wb64(out, os->fragments[i]->start_time);
        avio_wb32(out, os->fragments[i]->duration);
    }
    update_size(out, afrt_pos);
    update_size(out, 0);
    ff_format_io_close(s, &out);
    return ff_rename(temp_filename, filename, s);
}

static int init_file(AVFormatContext *s, OutputStream *os, int64_t start_ts)
{
    int ret, i;
    ret = s->io_open(s, &os->out, os->temp_filename, AVIO_FLAG_WRITE, NULL);
    if (ret < 0)
        return ret;
    avio_wb32(os->out, 0);
    avio_wl32(os->out, MKTAG('m','d','a','t'));
    for (i = 0; i < os->nb_extra_packets; i++) {
        AV_WB24(os->extra_packets[i] + 4, start_ts);
        os->extra_packets[i][7] = (start_ts >> 24) & 0x7f;
        avio_write(os->out, os->extra_packets[i], os->extra_packet_sizes[i]);
    }
    return 0;
}

static void close_file(AVFormatContext *s, OutputStream *os)
{
    int64_t pos = avio_tell(os->out);
    avio_seek(os->out, 0, SEEK_SET);
    avio_wb32(os->out, pos);
    avio_flush(os->out);
    ff_format_io_close(s, &os->out);
}

static int hds_write_header(AVFormatContext *s)
{
    HDSContext *c = s->priv_data;
    int ret = 0, i;
    AVOutputFormat *oformat;

    if (mkdir(s->filename, 0777) == -1 && errno != EEXIST) {
        ret = AVERROR(errno);
        av_log(s, AV_LOG_ERROR , "Failed to create directory %s\n", s->filename);
        goto fail;
    }

    oformat = av_guess_format("flv", NULL, NULL);
    if (!oformat) {
        ret = AVERROR_MUXER_NOT_FOUND;
        goto fail;
    }

    c->streams = av_mallocz_array(s->nb_streams, sizeof(*c->streams));
    if (!c->streams) {
        ret = AVERROR(ENOMEM);
        goto fail;
    }

    for (i = 0; i < s->nb_streams; i++) {
        OutputStream *os = &c->streams[c->nb_streams];
        AVFormatContext *ctx;
        AVStream *st = s->streams[i];

        if (!st->codecpar->bit_rate) {
            av_log(s, AV_LOG_ERROR, "No bit rate set for stream %d\n", i);
            ret = AVERROR(EINVAL);
            goto fail;
        }
        if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
            if (os->has_video) {
                c->nb_streams++;
                os++;
            }
            os->has_video = 1;
        } else if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
            if (os->has_audio) {
                c->nb_streams++;
                os++;
            }
            os->has_audio = 1;
        } else {
            av_log(s, AV_LOG_ERROR, "Unsupported stream type in stream %d\n", i);
            ret = AVERROR(EINVAL);
            goto fail;
        }
        os->bitrate += s->streams[i]->codecpar->bit_rate;

        if (!os->ctx) {
            os->first_stream = i;
            ctx = avformat_alloc_context();
            if (!ctx) {
                ret = AVERROR(ENOMEM);
                goto fail;
            }
            os->ctx = ctx;
            ctx->oformat = oformat;
            ctx->interrupt_callback = s->interrupt_callback;
            ctx->flags = s->flags;

            ctx->pb = avio_alloc_context(os->iobuf, sizeof(os->iobuf),
                                         AVIO_FLAG_WRITE, os,
                                         NULL, hds_write, NULL);
            if (!ctx->pb) {
                ret = AVERROR(ENOMEM);
                goto fail;
            }
        } else {
            ctx = os->ctx;
        }
        s->streams[i]->id = c->nb_streams;

        if (!(st = avformat_new_stream(ctx, NULL))) {
            ret = AVERROR(ENOMEM);
            goto fail;
        }
        avcodec_parameters_copy(st->codecpar, s->streams[i]->codecpar);
        st->codecpar->codec_tag = 0;
        st->sample_aspect_ratio = s->streams[i]->sample_aspect_ratio;
        st->time_base = s->streams[i]->time_base;
    }
    if (c->streams[c->nb_streams].ctx)
        c->nb_streams++;

    for (i = 0; i < c->nb_streams; i++) {
        OutputStream *os = &c->streams[i];
        int j;
        if ((ret = avformat_write_header(os->ctx, NULL)) < 0) {
             goto fail;
        }
        os->ctx_inited = 1;
        avio_flush(os->ctx->pb);
        for (j = 0; j < os->ctx->nb_streams; j++)
            s->streams[os->first_stream + j]->time_base = os->ctx->streams[j]->time_base;

        snprintf(os->temp_filename, sizeof(os->temp_filename),
                 "%s/stream%d_temp", s->filename, i);
        ret = init_file(s, os, 0);
        if (ret < 0)
            goto fail;

        if (!os->has_video && c->min_frag_duration <= 0) {
            av_log(s, AV_LOG_WARNING,
                   "No video stream in output stream %d and no min frag duration set\n", i);
            ret = AVERROR(EINVAL);
        }
        os->fragment_index = 1;
        write_abst(s, os, 0);
    }
    ret = write_manifest(s, 0);

fail:
    if (ret)
        hds_free(s);
    return ret;
}

static int add_fragment(OutputStream *os, const char *file,
                        int64_t start_time, int64_t duration)
{
    Fragment *frag;
    if (duration == 0)
        duration = 1;
    if (os->nb_fragments >= os->fragments_size) {
        int ret;
        os->fragments_size = (os->fragments_size + 1) * 2;
        if ((ret = av_reallocp_array(&os->fragments, os->fragments_size,
                                     sizeof(*os->fragments))) < 0) {
            os->fragments_size = 0;
            os->nb_fragments   = 0;
            return ret;
        }
    }
    frag = av_mallocz(sizeof(*frag));
    if (!frag)
        return AVERROR(ENOMEM);
    av_strlcpy(frag->file, file, sizeof(frag->file));
    frag->start_time = start_time;
    frag->duration   = duration;
    frag->n          = os->fragment_index;
    os->fragments[os->nb_fragments++] = frag;
    os->fragment_index++;
    return 0;
}

static int hds_flush(AVFormatContext *s, OutputStream *os, int final,
                     int64_t end_ts)
{
    HDSContext *c = s->priv_data;
    int i, ret = 0;
    char target_filename[1024];
    int index = s->streams[os->first_stream]->id;

    if (!os->packets_written)
        return 0;

    avio_flush(os->ctx->pb);
    os->packets_written = 0;
    close_file(s, os);

    snprintf(target_filename, sizeof(target_filename),
             "%s/stream%dSeg1-Frag%d", s->filename, index, os->fragment_index);
    ret = ff_rename(os->temp_filename, target_filename, s);
    if (ret < 0)
        return ret;
    add_fragment(os, target_filename, os->frag_start_ts, end_ts - os->frag_start_ts);

    if (!final) {
        ret = init_file(s, os, end_ts);
        if (ret < 0)
            return ret;
    }

    if (c->window_size || (final && c->remove_at_exit)) {
        int remove = os->nb_fragments - c->window_size - c->extra_window_size;
        if (final && c->remove_at_exit)
            remove = os->nb_fragments;
        if (remove > 0) {
            for (i = 0; i < remove; i++) {
                unlink(os->fragments[i]->file);
                av_freep(&os->fragments[i]);
            }
            os->nb_fragments -= remove;
            memmove(os->fragments, os->fragments + remove,
                    os->nb_fragments * sizeof(*os->fragments));
        }
    }

    if (ret >= 0)
        ret = write_abst(s, os, final);
    return ret;
}

static int hds_write_packet(AVFormatContext *s, AVPacket *pkt)
{
    HDSContext *c = s->priv_data;
    AVStream *st = s->streams[pkt->stream_index];
    OutputStream *os = &c->streams[s->streams[pkt->stream_index]->id];
    int64_t end_dts = os->fragment_index * (int64_t)c->min_frag_duration;
    int ret;

    if (st->first_dts == AV_NOPTS_VALUE)
        st->first_dts = pkt->dts;

    if ((!os->has_video || st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) &&
        av_compare_ts(pkt->dts - st->first_dts, st->time_base,
                      end_dts, AV_TIME_BASE_Q) >= 0 &&
        pkt->flags & AV_PKT_FLAG_KEY && os->packets_written) {

        if ((ret = hds_flush(s, os, 0, pkt->dts)) < 0)
            return ret;
    }

    // Note, these fragment start timestamps, that represent a whole
    // OutputStream, assume all streams in it have the same time base.
    if (!os->packets_written)
        os->frag_start_ts = pkt->dts;
    os->last_ts = pkt->dts;

    os->packets_written++;
    return ff_write_chained(os->ctx, pkt->stream_index - os->first_stream, pkt, s, 0);
}

static int hds_write_trailer(AVFormatContext *s)
{
    HDSContext *c = s->priv_data;
    int i;

    for (i = 0; i < c->nb_streams; i++)
        hds_flush(s, &c->streams[i], 1, c->streams[i].last_ts);
    write_manifest(s, 1);

    if (c->remove_at_exit) {
        char filename[1024];
        snprintf(filename, sizeof(filename), "%s/index.f4m", s->filename);
        unlink(filename);
        for (i = 0; i < c->nb_streams; i++) {
            snprintf(filename, sizeof(filename), "%s/stream%d.abst", s->filename, i);
            unlink(filename);
        }
        rmdir(s->filename);
    }

    hds_free(s);
    return 0;
}

#define OFFSET(x) offsetof(HDSContext, x)
#define E AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
    { "window_size", "number of fragments kept in the manifest", OFFSET(window_size), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, E },
    { "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 },
    { "min_frag_duration", "minimum fragment duration (in microseconds)", OFFSET(min_frag_duration), AV_OPT_TYPE_INT64, { .i64 = 10000000 }, 0, INT_MAX, E },
    { "remove_at_exit", "remove all fragments when finished", OFFSET(remove_at_exit), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, E },
    { NULL },
};

static const AVClass hds_class = {
    .class_name = "HDS muxer",
    .item_name  = av_default_item_name,
    .option     = options,
    .version    = LIBAVUTIL_VERSION_INT,
};

AVOutputFormat ff_hds_muxer = {
    .name           = "hds",
    .long_name      = NULL_IF_CONFIG_SMALL("HDS Muxer"),
    .priv_data_size = sizeof(HDSContext),
    .audio_codec    = AV_CODEC_ID_AAC,
    .video_codec    = AV_CODEC_ID_H264,
    .flags          = AVFMT_GLOBALHEADER | AVFMT_NOFILE,
    .write_header   = hds_write_header,
    .write_packet   = hds_write_packet,
    .write_trailer  = hds_write_trailer,
    .priv_class     = &hds_class,
};