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FFmpeg/libavformat/oggenc.c

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  1. /*

  2.  * Ogg muxer

  3.  * Copyright (c) 2007 Baptiste Coudurier <baptiste dot coudurier at free dot fr>

  4.  *

  5.  * This file is part of Libav.

  6.  *

  7.  * Libav 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.  * Libav 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 Libav; if not, write to the Free Software

  19.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  20.  */

  21. 

  22. #include "libavutil/crc.h"

  23. #include "libavutil/mathematics.h"

  24. #include "libavutil/opt.h"

  25. #include "libavutil/random_seed.h"

  26. #include "libavcodec/xiph.h"

  27. #include "libavcodec/bytestream.h"

  28. #include "libavcodec/flac.h"

  29. #include "avformat.h"

  30. #include "avio_internal.h"

  31. #include "internal.h"

  32. #include "vorbiscomment.h"

  33. 

  34. #define MAX_PAGE_SIZE 65025

  35. 

  36. typedef struct {

  37.     int64_t start_granule;

  38.     int64_t granule;

  39.     int stream_index;

  40.     uint8_t flags;

  41.     uint8_t segments_count;

  42.     uint8_t segments[255];

  43.     uint8_t data[MAX_PAGE_SIZE];

  44.     uint16_t size;

  45. } OGGPage;

  46. 

  47. typedef struct {

  48.     unsigned page_counter;

  49.     uint8_t *header[3];

  50.     int header_len[3];

  51.     /** for theora granule */

  52.     int kfgshift;

  53.     int64_t last_kf_pts;

  54.     int vrev;

  55.     int eos;

  56.     unsigned page_count; ///< number of page buffered

  57.     OGGPage page; ///< current page

  58.     unsigned serial_num; ///< serial number

  59.     int64_t last_granule; ///< last packet granule

  60. } OGGStreamContext;

  61. 

  62. typedef struct OGGPageList {

  63.     OGGPage page;

  64.     struct OGGPageList *next;

  65. } OGGPageList;

  66. 

  67. typedef struct {

  68.     const AVClass *class;

  69.     OGGPageList *page_list;

  70.     int pref_size; ///< preferred page size (0 => fill all segments)

  71.     int64_t pref_duration;      ///< preferred page duration (0 => fill all segments)

  72. } OGGContext;

  73. 

  74. #define OFFSET(x) offsetof(OGGContext, x)

  75. #define PARAM AV_OPT_FLAG_ENCODING_PARAM

  76. 

  77. static const AVOption options[] = {

  78.     { "pagesize", "preferred page size in bytes (deprecated)",

  79.         OFFSET(pref_size), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, MAX_PAGE_SIZE, PARAM },

  80.     { "page_duration", "preferred page duration, in microseconds",

  81.         OFFSET(pref_duration), AV_OPT_TYPE_INT, { .i64 = 1000000 }, 0, INT64_MAX, PARAM },

  82.     { NULL },

  83. };

  84. 

  85. static const AVClass ogg_muxer_class = {

  86.     .class_name = "Ogg muxer",

  87.     .item_name  = av_default_item_name,

  88.     .option     = options,

  89.     .version    = LIBAVUTIL_VERSION_INT,

  90. };

  91. 

  92. 

  93. static void ogg_update_checksum(AVFormatContext *s, AVIOContext *pb, int64_t crc_offset)

  94. {

  95.     int64_t pos = avio_tell(pb);

  96.     uint32_t checksum = ffio_get_checksum(pb);

  97.     avio_seek(pb, crc_offset, SEEK_SET);

  98.     avio_wb32(pb, checksum);

  99.     avio_seek(pb, pos, SEEK_SET);

  100. }

  101. 

  102. static int ogg_write_page(AVFormatContext *s, OGGPage *page, int extra_flags)

  103. {

  104.     OGGStreamContext *oggstream = s->streams[page->stream_index]->priv_data;

  105.     AVIOContext *pb;

  106.     int64_t crc_offset;

  107.     int ret, size;

  108.     uint8_t *buf;

  109. 

  110.     ret = avio_open_dyn_buf(&pb);

  111.     if (ret < 0)

  112.         return ret;

  113.     ffio_init_checksum(pb, ff_crc04C11DB7_update, 0);

  114.     ffio_wfourcc(pb, "OggS");

  115.     avio_w8(pb, 0);

  116.     avio_w8(pb, page->flags | extra_flags);

  117.     avio_wl64(pb, page->granule);

  118.     avio_wl32(pb, oggstream->serial_num);

  119.     avio_wl32(pb, oggstream->page_counter++);

  120.     crc_offset = avio_tell(pb);

  121.     avio_wl32(pb, 0); // crc

  122.     avio_w8(pb, page->segments_count);

  123.     avio_write(pb, page->segments, page->segments_count);

  124.     avio_write(pb, page->data, page->size);

  125. 

  126.     ogg_update_checksum(s, pb, crc_offset);

  127.     avio_flush(pb);

  128. 

  129.     size = avio_close_dyn_buf(pb, &buf);

  130.     if (size < 0)

  131.         return size;

  132. 

  133.     avio_write(s->pb, buf, size);

  134.     avio_flush(s->pb);

  135.     av_free(buf);

  136.     oggstream->page_count--;

  137.     return 0;

  138. }

  139. 

  140. static int64_t ogg_granule_to_timestamp(OGGStreamContext *oggstream, int64_t granule)

  141. {

  142.     if (oggstream->kfgshift)

  143.         return (granule>>oggstream->kfgshift) +

  144.             (granule & ((1<<oggstream->kfgshift)-1));

  145.     else

  146.         return granule;

  147. }

  148. 

  149. static int ogg_compare_granule(AVFormatContext *s, OGGPage *next, OGGPage *page)

  150. {

  151.     AVStream *st2 = s->streams[next->stream_index];

  152.     AVStream *st  = s->streams[page->stream_index];

  153.     int64_t next_granule, cur_granule;

  154. 

  155.     if (next->granule == -1 || page->granule == -1)

  156.         return 0;

  157. 

  158.     next_granule = av_rescale_q(ogg_granule_to_timestamp(st2->priv_data, next->granule),

  159.                                 st2->time_base, AV_TIME_BASE_Q);

  160.     cur_granule  = av_rescale_q(ogg_granule_to_timestamp(st->priv_data, page->granule),

  161.                                 st ->time_base, AV_TIME_BASE_Q);

  162.     return next_granule > cur_granule;

  163. }

  164. 

  165. static int ogg_reset_cur_page(OGGStreamContext *oggstream)

  166. {

  167.     oggstream->page.granule = -1;

  168.     oggstream->page.flags = 0;

  169.     oggstream->page.segments_count = 0;

  170.     oggstream->page.size = 0;

  171.     return 0;

  172. }

  173. 

  174. static int ogg_buffer_page(AVFormatContext *s, OGGStreamContext *oggstream)

  175. {

  176.     OGGContext *ogg = s->priv_data;

  177.     OGGPageList **p = &ogg->page_list;

  178.     OGGPageList *l = av_mallocz(sizeof(*l));

  179. 

  180.     if (!l)

  181.         return AVERROR(ENOMEM);

  182.     l->page = oggstream->page;

  183. 

  184.     oggstream->page.start_granule = oggstream->page.granule;

  185.     oggstream->page_count++;

  186.     ogg_reset_cur_page(oggstream);

  187. 

  188.     while (*p) {

  189.         if (ogg_compare_granule(s, &(*p)->page, &l->page))

  190.             break;

  191.         p = &(*p)->next;

  192.     }

  193.     l->next = *p;

  194.     *p = l;

  195. 

  196.     return 0;

  197. }

  198. 

  199. static int ogg_buffer_data(AVFormatContext *s, AVStream *st,

  200.                            uint8_t *data, unsigned size, int64_t granule,

  201.                            int header)

  202. {

  203.     OGGStreamContext *oggstream = st->priv_data;

  204.     OGGContext *ogg = s->priv_data;

  205.     int total_segments = size / 255 + 1;

  206.     uint8_t *p = data;

  207.     int i, segments, len, flush = 0;

  208. 

  209.     // Handles VFR by flushing page because this frame needs to have a timestamp

  210.     if (st->codec->codec_id == AV_CODEC_ID_THEORA && !header &&

  211.         ogg_granule_to_timestamp(oggstream, granule) >

  212.         ogg_granule_to_timestamp(oggstream, oggstream->last_granule) + 1) {

  213.         if (oggstream->page.granule != -1)

  214.             ogg_buffer_page(s, oggstream);

  215.         flush = 1;

  216.     }

  217. 

  218.     // avoid a continued page

  219.     if (!header && oggstream->page.size > 0 &&

  220.         MAX_PAGE_SIZE - oggstream->page.size < size) {

  221.         ogg_buffer_page(s, oggstream);

  222.     }

  223. 

  224.     for (i = 0; i < total_segments; ) {

  225.         OGGPage *page = &oggstream->page;

  226. 

  227.         segments = FFMIN(total_segments - i, 255 - page->segments_count);

  228. 

  229.         if (i && !page->segments_count)

  230.             page->flags |= 1; // continued packet

  231. 

  232.         memset(page->segments+page->segments_count, 255, segments - 1);

  233.         page->segments_count += segments - 1;

  234. 

  235.         len = FFMIN(size, segments*255);

  236.         page->segments[page->segments_count++] = len - (segments-1)*255;

  237.         memcpy(page->data+page->size, p, len);

  238.         p += len;

  239.         size -= len;

  240.         i += segments;

  241.         page->size += len;

  242. 

  243.         if (i == total_segments)

  244.             page->granule = granule;

  245. 

  246.         if (!header) {

  247.             AVStream *st = s->streams[page->stream_index];

  248. 

  249.             int64_t start = av_rescale_q(page->start_granule, st->time_base,

  250.                                          AV_TIME_BASE_Q);

  251.             int64_t next  = av_rescale_q(page->granule, st->time_base,

  252.                                          AV_TIME_BASE_Q);

  253. 

  254.             if (page->segments_count == 255 ||

  255.                 (ogg->pref_size     > 0 && page->size   >= ogg->pref_size) ||

  256.                 (ogg->pref_duration > 0 && next - start >= ogg->pref_duration)) {

  257.                 ogg_buffer_page(s, oggstream);

  258.             }

  259.         }

  260.     }

  261. 

  262.     if (flush && oggstream->page.granule != -1)

  263.         ogg_buffer_page(s, oggstream);

  264. 

  265.     return 0;

  266. }

  267. 

  268. static uint8_t *ogg_write_vorbiscomment(int offset, int bitexact,

  269.                                         int *header_len, AVDictionary **m, int framing_bit)

  270. {

  271.     const char *vendor = bitexact ? "Libav" : LIBAVFORMAT_IDENT;

  272.     int size;

  273.     uint8_t *p, *p0;

  274.     unsigned int count;

  275. 

  276.     ff_metadata_conv(m, ff_vorbiscomment_metadata_conv, NULL);

  277. 

  278.     size = offset + ff_vorbiscomment_length(*m, vendor, &count) + framing_bit;

  279.     p = av_mallocz(size);

  280.     if (!p)

  281.         return NULL;

  282.     p0 = p;

  283. 

  284.     p += offset;

  285.     ff_vorbiscomment_write(&p, m, vendor, count);

  286.     if (framing_bit)

  287.         bytestream_put_byte(&p, 1);

  288. 

  289.     *header_len = size;

  290.     return p0;

  291. }

  292. 

  293. static int ogg_build_flac_headers(AVCodecContext *avctx,

  294.                                   OGGStreamContext *oggstream, int bitexact,

  295.                                   AVDictionary **m)

  296. {

  297.     enum FLACExtradataFormat format;

  298.     uint8_t *streaminfo;

  299.     uint8_t *p;

  300. 

  301.     if (!avpriv_flac_is_extradata_valid(avctx, &format, &streaminfo))

  302.         return -1;

  303. 

  304.     // first packet: STREAMINFO

  305.     oggstream->header_len[0] = 51;

  306.     oggstream->header[0] = av_mallocz(51); // per ogg flac specs

  307.     p = oggstream->header[0];

  308.     if (!p)

  309.         return AVERROR(ENOMEM);

  310.     bytestream_put_byte(&p, 0x7F);

  311.     bytestream_put_buffer(&p, "FLAC", 4);

  312.     bytestream_put_byte(&p, 1); // major version

  313.     bytestream_put_byte(&p, 0); // minor version

  314.     bytestream_put_be16(&p, 1); // headers packets without this one

  315.     bytestream_put_buffer(&p, "fLaC", 4);

  316.     bytestream_put_byte(&p, 0x00); // streaminfo

  317.     bytestream_put_be24(&p, 34);

  318.     bytestream_put_buffer(&p, streaminfo, FLAC_STREAMINFO_SIZE);

  319. 

  320.     // second packet: VorbisComment

  321.     p = ogg_write_vorbiscomment(4, bitexact, &oggstream->header_len[1], m, 0);

  322.     if (!p)

  323.         return AVERROR(ENOMEM);

  324.     oggstream->header[1] = p;

  325.     bytestream_put_byte(&p, 0x84); // last metadata block and vorbis comment

  326.     bytestream_put_be24(&p, oggstream->header_len[1] - 4);

  327. 

  328.     return 0;

  329. }

  330. 

  331. #define SPEEX_HEADER_SIZE 80

  332. 

  333. static int ogg_build_speex_headers(AVCodecContext *avctx,

  334.                                    OGGStreamContext *oggstream, int bitexact,

  335.                                    AVDictionary **m)

  336. {

  337.     uint8_t *p;

  338. 

  339.     if (avctx->extradata_size < SPEEX_HEADER_SIZE)

  340.         return -1;

  341. 

  342.     // first packet: Speex header

  343.     p = av_mallocz(SPEEX_HEADER_SIZE);

  344.     if (!p)

  345.         return AVERROR(ENOMEM);

  346.     oggstream->header[0] = p;

  347.     oggstream->header_len[0] = SPEEX_HEADER_SIZE;

  348.     bytestream_put_buffer(&p, avctx->extradata, SPEEX_HEADER_SIZE);

  349.     AV_WL32(&oggstream->header[0][68], 0);  // set extra_headers to 0

  350. 

  351.     // second packet: VorbisComment

  352.     p = ogg_write_vorbiscomment(0, bitexact, &oggstream->header_len[1], m, 0);

  353.     if (!p)

  354.         return AVERROR(ENOMEM);

  355.     oggstream->header[1] = p;

  356. 

  357.     return 0;

  358. }

  359. 

  360. #define OPUS_HEADER_SIZE 19

  361. 

  362. static int ogg_build_opus_headers(AVCodecContext *avctx,

  363.                                   OGGStreamContext *oggstream, int bitexact,

  364.                                   AVDictionary **m)

  365. {

  366.     uint8_t *p;

  367. 

  368.     if (avctx->extradata_size < OPUS_HEADER_SIZE)

  369.         return -1;

  370. 

  371.     /* first packet: Opus header */

  372.     p = av_mallocz(avctx->extradata_size);

  373.     if (!p)

  374.         return AVERROR(ENOMEM);

  375.     oggstream->header[0] = p;

  376.     oggstream->header_len[0] = avctx->extradata_size;

  377.     bytestream_put_buffer(&p, avctx->extradata, avctx->extradata_size);

  378. 

  379.     /* second packet: VorbisComment */

  380.     p = ogg_write_vorbiscomment(8, bitexact, &oggstream->header_len[1], m, 0);

  381.     if (!p)

  382.         return AVERROR(ENOMEM);

  383.     oggstream->header[1] = p;

  384.     bytestream_put_buffer(&p, "OpusTags", 8);

  385. 

  386.     return 0;

  387. }

  388. 

  389. static int ogg_write_header(AVFormatContext *s)

  390. {

  391.     OGGContext *ogg = s->priv_data;

  392.     OGGStreamContext *oggstream;

  393.     int i, j;

  394. 

  395.     if (ogg->pref_size)

  396.         av_log(s, AV_LOG_WARNING, "The pagesize option is deprecated\n");

  397. 

  398.     for (i = 0; i < s->nb_streams; i++) {

  399.         AVStream *st = s->streams[i];

  400.         unsigned serial_num = i;

  401. 

  402.         if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO)

  403.             if (st->codec->codec_id == AV_CODEC_ID_OPUS)

  404.                 /* Opus requires a fixed 48kHz clock */

  405.                 avpriv_set_pts_info(st, 64, 1, 48000);

  406.             else

  407.                 avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);

  408.         else if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO)

  409.             avpriv_set_pts_info(st, 64, st->codec->time_base.num, st->codec->time_base.den);

  410.         if (st->codec->codec_id != AV_CODEC_ID_VORBIS &&

  411.             st->codec->codec_id != AV_CODEC_ID_THEORA &&

  412.             st->codec->codec_id != AV_CODEC_ID_SPEEX  &&

  413.             st->codec->codec_id != AV_CODEC_ID_FLAC   &&

  414.             st->codec->codec_id != AV_CODEC_ID_OPUS) {

  415.             av_log(s, AV_LOG_ERROR, "Unsupported codec id in stream %d\n", i);

  416.             return -1;

  417.         }

  418. 

  419.         if (!st->codec->extradata || !st->codec->extradata_size) {

  420.             av_log(s, AV_LOG_ERROR, "No extradata present\n");

  421.             return -1;

  422.         }

  423.         oggstream = av_mallocz(sizeof(*oggstream));

  424.         oggstream->page.stream_index = i;

  425. 

  426.         if (!(st->codec->flags & CODEC_FLAG_BITEXACT))

  427.             do {

  428.                 serial_num = av_get_random_seed();

  429.                 for (j = 0; j < i; j++) {

  430.                     OGGStreamContext *sc = s->streams[j]->priv_data;

  431.                     if (serial_num == sc->serial_num)

  432.                         break;

  433.                 }

  434.             } while (j < i);

  435.         oggstream->serial_num = serial_num;

  436. 

  437.         st->priv_data = oggstream;

  438.         if (st->codec->codec_id == AV_CODEC_ID_FLAC) {

  439.             int err = ogg_build_flac_headers(st->codec, oggstream,

  440.                                              st->codec->flags & CODEC_FLAG_BITEXACT,

  441.                                              &s->metadata);

  442.             if (err) {

  443.                 av_log(s, AV_LOG_ERROR, "Error writing FLAC headers\n");

  444.                 av_freep(&st->priv_data);

  445.                 return err;

  446.             }

  447.         } else if (st->codec->codec_id == AV_CODEC_ID_SPEEX) {

  448.             int err = ogg_build_speex_headers(st->codec, oggstream,

  449.                                               st->codec->flags & CODEC_FLAG_BITEXACT,

  450.                                               &s->metadata);

  451.             if (err) {

  452.                 av_log(s, AV_LOG_ERROR, "Error writing Speex headers\n");

  453.                 av_freep(&st->priv_data);

  454.                 return err;

  455.             }

  456.         } else if (st->codec->codec_id == AV_CODEC_ID_OPUS) {

  457.             int err = ogg_build_opus_headers(st->codec, oggstream,

  458.                                              st->codec->flags & CODEC_FLAG_BITEXACT,

  459.                                              &s->metadata);

  460.             if (err) {

  461.                 av_log(s, AV_LOG_ERROR, "Error writing Opus headers\n");

  462.                 av_freep(&st->priv_data);

  463.                 return err;

  464.             }

  465.         } else {

  466.             uint8_t *p;

  467.             const char *cstr = st->codec->codec_id == AV_CODEC_ID_VORBIS ? "vorbis" : "theora";

  468.             int header_type = st->codec->codec_id == AV_CODEC_ID_VORBIS ? 3 : 0x81;

  469.             int framing_bit = st->codec->codec_id == AV_CODEC_ID_VORBIS ? 1 : 0;

  470. 

  471.             if (avpriv_split_xiph_headers(st->codec->extradata, st->codec->extradata_size,

  472.                                       st->codec->codec_id == AV_CODEC_ID_VORBIS ? 30 : 42,

  473.                                       oggstream->header, oggstream->header_len) < 0) {

  474.                 av_log(s, AV_LOG_ERROR, "Extradata corrupted\n");

  475.                 av_freep(&st->priv_data);

  476.                 return -1;

  477.             }

  478. 

  479.             p = ogg_write_vorbiscomment(7, st->codec->flags & CODEC_FLAG_BITEXACT,

  480.                                         &oggstream->header_len[1], &s->metadata,

  481.                                         framing_bit);

  482.             oggstream->header[1] = p;

  483.             if (!p)

  484.                 return AVERROR(ENOMEM);

  485. 

  486.             bytestream_put_byte(&p, header_type);

  487.             bytestream_put_buffer(&p, cstr, 6);

  488. 

  489.             if (st->codec->codec_id == AV_CODEC_ID_THEORA) {

  490.                 /** KFGSHIFT is the width of the less significant section of the granule position

  491.                     The less significant section is the frame count since the last keyframe */

  492.                 oggstream->kfgshift = ((oggstream->header[0][40]&3)<<3)|(oggstream->header[0][41]>>5);

  493.                 oggstream->vrev = oggstream->header[0][9];

  494.                 av_log(s, AV_LOG_DEBUG, "theora kfgshift %d, vrev %d\n",

  495.                        oggstream->kfgshift, oggstream->vrev);

  496.             }

  497.         }

  498.     }

  499. 

  500.     for (j = 0; j < s->nb_streams; j++) {

  501.         OGGStreamContext *oggstream = s->streams[j]->priv_data;

  502.         ogg_buffer_data(s, s->streams[j], oggstream->header[0],

  503.                         oggstream->header_len[0], 0, 1);

  504.         oggstream->page.flags |= 2; // bos

  505.         ogg_buffer_page(s, oggstream);

  506.     }

  507.     for (j = 0; j < s->nb_streams; j++) {

  508.         AVStream *st = s->streams[j];

  509.         OGGStreamContext *oggstream = st->priv_data;

  510.         for (i = 1; i < 3; i++) {

  511.             if (oggstream && oggstream->header_len[i])

  512.                 ogg_buffer_data(s, st, oggstream->header[i],

  513.                                 oggstream->header_len[i], 0, 1);

  514.         }

  515.         ogg_buffer_page(s, oggstream);

  516.     }

  517. 

  518.     oggstream->page.start_granule = AV_NOPTS_VALUE;

  519. 

  520.     return 0;

  521. }

  522. 

  523. static void ogg_write_pages(AVFormatContext *s, int flush)

  524. {

  525.     OGGContext *ogg = s->priv_data;

  526.     OGGPageList *next, *p;

  527. 

  528.     if (!ogg->page_list)

  529.         return;

  530. 

  531.     for (p = ogg->page_list; p; ) {

  532.         OGGStreamContext *oggstream =

  533.             s->streams[p->page.stream_index]->priv_data;

  534.         if (oggstream->page_count < 2 && !flush)

  535.             break;

  536.         ogg_write_page(s, &p->page,

  537.                        flush && oggstream->page_count == 1 ? 4 : 0); // eos

  538.         next = p->next;

  539.         av_freep(&p);

  540.         p = next;

  541.     }

  542.     ogg->page_list = p;

  543. }

  544. 

  545. static int ogg_write_packet(AVFormatContext *s, AVPacket *pkt)

  546. {

  547.     AVStream *st = s->streams[pkt->stream_index];

  548.     OGGStreamContext *oggstream = st->priv_data;

  549.     int ret;

  550.     int64_t granule;

  551. 

  552.     if (st->codec->codec_id == AV_CODEC_ID_THEORA) {

  553.         int64_t pts = oggstream->vrev < 1 ? pkt->pts : pkt->pts + pkt->duration;

  554.         int pframe_count;

  555.         if (pkt->flags & AV_PKT_FLAG_KEY)

  556.             oggstream->last_kf_pts = pts;

  557.         pframe_count = pts - oggstream->last_kf_pts;

  558.         // prevent frame count from overflow if key frame flag is not set

  559.         if (pframe_count >= (1<<oggstream->kfgshift)) {

  560.             oggstream->last_kf_pts += pframe_count;

  561.             pframe_count = 0;

  562.         }

  563.         granule = (oggstream->last_kf_pts<<oggstream->kfgshift) | pframe_count;

  564.     } else if (st->codec->codec_id == AV_CODEC_ID_OPUS)

  565.         granule = pkt->pts + pkt->duration + av_rescale_q(st->codec->delay, (AVRational){ 1, st->codec->sample_rate }, st->time_base);

  566.     else

  567.         granule = pkt->pts + pkt->duration;

  568. 

  569.     if (oggstream->page.start_granule == AV_NOPTS_VALUE)

  570.         oggstream->page.start_granule = pkt->pts;

  571. 

  572.     ret = ogg_buffer_data(s, st, pkt->data, pkt->size, granule, 0);

  573.     if (ret < 0)

  574.         return ret;

  575. 

  576.     ogg_write_pages(s, 0);

  577. 

  578.     oggstream->last_granule = granule;

  579. 

  580.     return 0;

  581. }

  582. 

  583. static int ogg_write_trailer(AVFormatContext *s)

  584. {

  585.     int i;

  586. 

  587.     /* flush current page if needed */

  588.     for (i = 0; i < s->nb_streams; i++) {

  589.         OGGStreamContext *oggstream = s->streams[i]->priv_data;

  590. 

  591.         if (oggstream->page.size > 0)

  592.             ogg_buffer_page(s, oggstream);

  593.     }

  594. 

  595.     ogg_write_pages(s, 1);

  596. 

  597.     for (i = 0; i < s->nb_streams; i++) {

  598.         AVStream *st = s->streams[i];

  599.         OGGStreamContext *oggstream = st->priv_data;

  600.         if (st->codec->codec_id == AV_CODEC_ID_FLAC ||

  601.             st->codec->codec_id == AV_CODEC_ID_SPEEX ||

  602.             st->codec->codec_id == AV_CODEC_ID_OPUS) {

  603.             av_free(oggstream->header[0]);

  604.         }

  605.         av_freep(&oggstream->header[1]);

  606.         av_freep(&st->priv_data);

  607.     }

  608.     return 0;

  609. }

  610. 

  611. AVOutputFormat ff_ogg_muxer = {

  612.     .name              = "ogg",

  613.     .long_name         = NULL_IF_CONFIG_SMALL("Ogg"),

  614.     .mime_type         = "application/ogg",

  615.     .extensions        = "ogg,ogv,spx,opus",

  616.     .priv_data_size    = sizeof(OGGContext),

  617.     .audio_codec       = AV_CODEC_ID_FLAC,

  618.     .video_codec       = AV_CODEC_ID_THEORA,

  619.     .write_header      = ogg_write_header,

  620.     .write_packet      = ogg_write_packet,

  621.     .write_trailer     = ogg_write_trailer,

  622.     .priv_class        = &ogg_muxer_class,

  623. };