yading@11: /*
yading@11:  * Ogg muxer
yading@11:  * Copyright (c) 2007 Baptiste Coudurier <baptiste dot coudurier at free dot fr>
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: #include "libavutil/crc.h"
yading@11: #include "libavutil/opt.h"
yading@11: #include "libavutil/mathematics.h"
yading@11: #include "libavutil/opt.h"
yading@11: #include "libavutil/random_seed.h"
yading@11: #include "libavcodec/xiph.h"
yading@11: #include "libavcodec/bytestream.h"
yading@11: #include "libavcodec/flac.h"
yading@11: #include "avformat.h"
yading@11: #include "avio_internal.h"
yading@11: #include "internal.h"
yading@11: #include "vorbiscomment.h"
yading@11: 
yading@11: #define MAX_PAGE_SIZE 65025
yading@11: 
yading@11: typedef struct {
yading@11:     int64_t start_granule;
yading@11:     int64_t granule;
yading@11:     int stream_index;
yading@11:     uint8_t flags;
yading@11:     uint8_t segments_count;
yading@11:     uint8_t segments[255];
yading@11:     uint8_t data[MAX_PAGE_SIZE];
yading@11:     uint16_t size;
yading@11: } OGGPage;
yading@11: 
yading@11: typedef struct {
yading@11:     unsigned page_counter;
yading@11:     uint8_t *header[3];
yading@11:     int header_len[3];
yading@11:     /** for theora granule */
yading@11:     int kfgshift;
yading@11:     int64_t last_kf_pts;
yading@11:     int vrev;
yading@11:     int eos;
yading@11:     unsigned page_count; ///< number of page buffered
yading@11:     OGGPage page; ///< current page
yading@11:     unsigned serial_num; ///< serial number
yading@11:     int64_t last_granule; ///< last packet granule
yading@11: } OGGStreamContext;
yading@11: 
yading@11: typedef struct OGGPageList {
yading@11:     OGGPage page;
yading@11:     struct OGGPageList *next;
yading@11: } OGGPageList;
yading@11: 
yading@11: typedef struct {
yading@11:     const AVClass *class;
yading@11:     OGGPageList *page_list;
yading@11:     int pref_size; ///< preferred page size (0 => fill all segments)
yading@11:     int64_t pref_duration;      ///< preferred page duration (0 => fill all segments)
yading@11: } OGGContext;
yading@11: 
yading@11: #define OFFSET(x) offsetof(OGGContext, x)
yading@11: #define PARAM AV_OPT_FLAG_ENCODING_PARAM
yading@11: 
yading@11: static const AVOption options[] = {
yading@11:     { "oggpagesize", "Set preferred Ogg page size.",
yading@11:       offsetof(OGGContext, pref_size), AV_OPT_TYPE_INT, {.i64 = 0}, 0, MAX_PAGE_SIZE, AV_OPT_FLAG_ENCODING_PARAM},
yading@11:     { "pagesize", "preferred page size in bytes (deprecated)",
yading@11:         OFFSET(pref_size), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, MAX_PAGE_SIZE, PARAM },
yading@11:     { "page_duration", "preferred page duration, in microseconds",
yading@11:         OFFSET(pref_duration), AV_OPT_TYPE_INT64, { .i64 = 1000000 }, 0, INT64_MAX, PARAM },
yading@11:     { NULL },
yading@11: };
yading@11: 
yading@11: static const AVClass ogg_muxer_class = {
yading@11:     .class_name = "Ogg muxer",
yading@11:     .item_name  = av_default_item_name,
yading@11:     .option     = options,
yading@11:     .version    = LIBAVUTIL_VERSION_INT,
yading@11: };
yading@11: 
yading@11: 
yading@11: static void ogg_update_checksum(AVFormatContext *s, AVIOContext *pb, int64_t crc_offset)
yading@11: {
yading@11:     int64_t pos = avio_tell(pb);
yading@11:     uint32_t checksum = ffio_get_checksum(pb);
yading@11:     avio_seek(pb, crc_offset, SEEK_SET);
yading@11:     avio_wb32(pb, checksum);
yading@11:     avio_seek(pb, pos, SEEK_SET);
yading@11: }
yading@11: 
yading@11: static int ogg_write_page(AVFormatContext *s, OGGPage *page, int extra_flags)
yading@11: {
yading@11:     OGGStreamContext *oggstream = s->streams[page->stream_index]->priv_data;
yading@11:     AVIOContext *pb;
yading@11:     int64_t crc_offset;
yading@11:     int ret, size;
yading@11:     uint8_t *buf;
yading@11: 
yading@11:     ret = avio_open_dyn_buf(&pb);
yading@11:     if (ret < 0)
yading@11:         return ret;
yading@11:     ffio_init_checksum(pb, ff_crc04C11DB7_update, 0);
yading@11:     ffio_wfourcc(pb, "OggS");
yading@11:     avio_w8(pb, 0);
yading@11:     avio_w8(pb, page->flags | extra_flags);
yading@11:     avio_wl64(pb, page->granule);
yading@11:     avio_wl32(pb, oggstream->serial_num);
yading@11:     avio_wl32(pb, oggstream->page_counter++);
yading@11:     crc_offset = avio_tell(pb);
yading@11:     avio_wl32(pb, 0); // crc
yading@11:     avio_w8(pb, page->segments_count);
yading@11:     avio_write(pb, page->segments, page->segments_count);
yading@11:     avio_write(pb, page->data, page->size);
yading@11: 
yading@11:     ogg_update_checksum(s, pb, crc_offset);
yading@11:     avio_flush(pb);
yading@11: 
yading@11:     size = avio_close_dyn_buf(pb, &buf);
yading@11:     if (size < 0)
yading@11:         return size;
yading@11: 
yading@11:     avio_write(s->pb, buf, size);
yading@11:     avio_flush(s->pb);
yading@11:     av_free(buf);
yading@11:     oggstream->page_count--;
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int ogg_key_granule(OGGStreamContext *oggstream, int64_t granule)
yading@11: {
yading@11:     return oggstream->kfgshift && !(granule & ((1<<oggstream->kfgshift)-1));
yading@11: }
yading@11: 
yading@11: static int64_t ogg_granule_to_timestamp(OGGStreamContext *oggstream, int64_t granule)
yading@11: {
yading@11:     if (oggstream->kfgshift)
yading@11:         return (granule>>oggstream->kfgshift) +
yading@11:             (granule & ((1<<oggstream->kfgshift)-1));
yading@11:     else
yading@11:         return granule;
yading@11: }
yading@11: 
yading@11: static int ogg_compare_granule(AVFormatContext *s, OGGPage *next, OGGPage *page)
yading@11: {
yading@11:     AVStream *st2 = s->streams[next->stream_index];
yading@11:     AVStream *st  = s->streams[page->stream_index];
yading@11:     int64_t next_granule, cur_granule;
yading@11: 
yading@11:     if (next->granule == -1 || page->granule == -1)
yading@11:         return 0;
yading@11: 
yading@11:     next_granule = av_rescale_q(ogg_granule_to_timestamp(st2->priv_data, next->granule),
yading@11:                                 st2->time_base, AV_TIME_BASE_Q);
yading@11:     cur_granule  = av_rescale_q(ogg_granule_to_timestamp(st->priv_data, page->granule),
yading@11:                                 st ->time_base, AV_TIME_BASE_Q);
yading@11:     return next_granule > cur_granule;
yading@11: }
yading@11: 
yading@11: static int ogg_reset_cur_page(OGGStreamContext *oggstream)
yading@11: {
yading@11:     oggstream->page.granule = -1;
yading@11:     oggstream->page.flags = 0;
yading@11:     oggstream->page.segments_count = 0;
yading@11:     oggstream->page.size = 0;
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int ogg_buffer_page(AVFormatContext *s, OGGStreamContext *oggstream)
yading@11: {
yading@11:     OGGContext *ogg = s->priv_data;
yading@11:     OGGPageList **p = &ogg->page_list;
yading@11:     OGGPageList *l = av_mallocz(sizeof(*l));
yading@11: 
yading@11:     if (!l)
yading@11:         return AVERROR(ENOMEM);
yading@11:     l->page = oggstream->page;
yading@11: 
yading@11:     oggstream->page.start_granule = oggstream->page.granule;
yading@11:     oggstream->page_count++;
yading@11:     ogg_reset_cur_page(oggstream);
yading@11: 
yading@11:     while (*p) {
yading@11:         if (ogg_compare_granule(s, &(*p)->page, &l->page))
yading@11:             break;
yading@11:         p = &(*p)->next;
yading@11:     }
yading@11:     l->next = *p;
yading@11:     *p = l;
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int ogg_buffer_data(AVFormatContext *s, AVStream *st,
yading@11:                            uint8_t *data, unsigned size, int64_t granule,
yading@11:                            int header)
yading@11: {
yading@11:     OGGStreamContext *oggstream = st->priv_data;
yading@11:     OGGContext *ogg = s->priv_data;
yading@11:     int total_segments = size / 255 + 1;
yading@11:     uint8_t *p = data;
yading@11:     int i, segments, len, flush = 0;
yading@11: 
yading@11:     // Handles VFR by flushing page because this frame needs to have a timestamp
yading@11:     // For theora, keyframes also need to have a timestamp to correctly mark
yading@11:     // them as such, otherwise seeking will not work correctly at the very
yading@11:     // least with old libogg versions.
yading@11:     // Do not try to flush header packets though, that will create broken files.
yading@11:     if (st->codec->codec_id == AV_CODEC_ID_THEORA && !header &&
yading@11:         (ogg_granule_to_timestamp(oggstream, granule) >
yading@11:          ogg_granule_to_timestamp(oggstream, oggstream->last_granule) + 1 ||
yading@11:          ogg_key_granule(oggstream, granule))) {
yading@11:         if (oggstream->page.granule != -1)
yading@11:             ogg_buffer_page(s, oggstream);
yading@11:         flush = 1;
yading@11:     }
yading@11: 
yading@11:     // avoid a continued page
yading@11:     if (!header && oggstream->page.size > 0 &&
yading@11:         MAX_PAGE_SIZE - oggstream->page.size < size) {
yading@11:         ogg_buffer_page(s, oggstream);
yading@11:     }
yading@11: 
yading@11:     for (i = 0; i < total_segments; ) {
yading@11:         OGGPage *page = &oggstream->page;
yading@11: 
yading@11:         segments = FFMIN(total_segments - i, 255 - page->segments_count);
yading@11: 
yading@11:         if (i && !page->segments_count)
yading@11:             page->flags |= 1; // continued packet
yading@11: 
yading@11:         memset(page->segments+page->segments_count, 255, segments - 1);
yading@11:         page->segments_count += segments - 1;
yading@11: 
yading@11:         len = FFMIN(size, segments*255);
yading@11:         page->segments[page->segments_count++] = len - (segments-1)*255;
yading@11:         memcpy(page->data+page->size, p, len);
yading@11:         p += len;
yading@11:         size -= len;
yading@11:         i += segments;
yading@11:         page->size += len;
yading@11: 
yading@11:         if (i == total_segments)
yading@11:             page->granule = granule;
yading@11: 
yading@11:         if (!header) {
yading@11:             AVStream *st = s->streams[page->stream_index];
yading@11: 
yading@11:             int64_t start = av_rescale_q(page->start_granule, st->time_base,
yading@11:                                          AV_TIME_BASE_Q);
yading@11:             int64_t next  = av_rescale_q(page->granule, st->time_base,
yading@11:                                          AV_TIME_BASE_Q);
yading@11: 
yading@11:             if (page->segments_count == 255 ||
yading@11:                 (ogg->pref_size     > 0 && page->size   >= ogg->pref_size) ||
yading@11:                 (ogg->pref_duration > 0 && next - start >= ogg->pref_duration)) {
yading@11:                 ogg_buffer_page(s, oggstream);
yading@11:             }
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     if (flush && oggstream->page.granule != -1)
yading@11:         ogg_buffer_page(s, oggstream);
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static uint8_t *ogg_write_vorbiscomment(int offset, int bitexact,
yading@11:                                         int *header_len, AVDictionary **m, int framing_bit)
yading@11: {
yading@11:     const char *vendor = bitexact ? "ffmpeg" : LIBAVFORMAT_IDENT;
yading@11:     int size;
yading@11:     uint8_t *p, *p0;
yading@11:     unsigned int count;
yading@11: 
yading@11:     ff_metadata_conv(m, ff_vorbiscomment_metadata_conv, NULL);
yading@11: 
yading@11:     size = offset + ff_vorbiscomment_length(*m, vendor, &count) + framing_bit;
yading@11:     p = av_mallocz(size);
yading@11:     if (!p)
yading@11:         return NULL;
yading@11:     p0 = p;
yading@11: 
yading@11:     p += offset;
yading@11:     ff_vorbiscomment_write(&p, m, vendor, count);
yading@11:     if (framing_bit)
yading@11:         bytestream_put_byte(&p, 1);
yading@11: 
yading@11:     *header_len = size;
yading@11:     return p0;
yading@11: }
yading@11: 
yading@11: static int ogg_build_flac_headers(AVCodecContext *avctx,
yading@11:                                   OGGStreamContext *oggstream, int bitexact,
yading@11:                                   AVDictionary **m)
yading@11: {
yading@11:     enum FLACExtradataFormat format;
yading@11:     uint8_t *streaminfo;
yading@11:     uint8_t *p;
yading@11: 
yading@11:     if (!avpriv_flac_is_extradata_valid(avctx, &format, &streaminfo))
yading@11:         return -1;
yading@11: 
yading@11:     // first packet: STREAMINFO
yading@11:     oggstream->header_len[0] = 51;
yading@11:     oggstream->header[0] = av_mallocz(51); // per ogg flac specs
yading@11:     p = oggstream->header[0];
yading@11:     if (!p)
yading@11:         return AVERROR(ENOMEM);
yading@11:     bytestream_put_byte(&p, 0x7F);
yading@11:     bytestream_put_buffer(&p, "FLAC", 4);
yading@11:     bytestream_put_byte(&p, 1); // major version
yading@11:     bytestream_put_byte(&p, 0); // minor version
yading@11:     bytestream_put_be16(&p, 1); // headers packets without this one
yading@11:     bytestream_put_buffer(&p, "fLaC", 4);
yading@11:     bytestream_put_byte(&p, 0x00); // streaminfo
yading@11:     bytestream_put_be24(&p, 34);
yading@11:     bytestream_put_buffer(&p, streaminfo, FLAC_STREAMINFO_SIZE);
yading@11: 
yading@11:     // second packet: VorbisComment
yading@11:     p = ogg_write_vorbiscomment(4, bitexact, &oggstream->header_len[1], m, 0);
yading@11:     if (!p)
yading@11:         return AVERROR(ENOMEM);
yading@11:     oggstream->header[1] = p;
yading@11:     bytestream_put_byte(&p, 0x84); // last metadata block and vorbis comment
yading@11:     bytestream_put_be24(&p, oggstream->header_len[1] - 4);
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: #define SPEEX_HEADER_SIZE 80
yading@11: 
yading@11: static int ogg_build_speex_headers(AVCodecContext *avctx,
yading@11:                                    OGGStreamContext *oggstream, int bitexact,
yading@11:                                    AVDictionary **m)
yading@11: {
yading@11:     uint8_t *p;
yading@11: 
yading@11:     if (avctx->extradata_size < SPEEX_HEADER_SIZE)
yading@11:         return -1;
yading@11: 
yading@11:     // first packet: Speex header
yading@11:     p = av_mallocz(SPEEX_HEADER_SIZE);
yading@11:     if (!p)
yading@11:         return AVERROR(ENOMEM);
yading@11:     oggstream->header[0] = p;
yading@11:     oggstream->header_len[0] = SPEEX_HEADER_SIZE;
yading@11:     bytestream_put_buffer(&p, avctx->extradata, SPEEX_HEADER_SIZE);
yading@11:     AV_WL32(&oggstream->header[0][68], 0);  // set extra_headers to 0
yading@11: 
yading@11:     // second packet: VorbisComment
yading@11:     p = ogg_write_vorbiscomment(0, bitexact, &oggstream->header_len[1], m, 0);
yading@11:     if (!p)
yading@11:         return AVERROR(ENOMEM);
yading@11:     oggstream->header[1] = p;
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: #define OPUS_HEADER_SIZE 19
yading@11: 
yading@11: static int ogg_build_opus_headers(AVCodecContext *avctx,
yading@11:                                   OGGStreamContext *oggstream, int bitexact,
yading@11:                                   AVDictionary **m)
yading@11: {
yading@11:     uint8_t *p;
yading@11: 
yading@11:     if (avctx->extradata_size < OPUS_HEADER_SIZE)
yading@11:         return -1;
yading@11: 
yading@11:     /* first packet: Opus header */
yading@11:     p = av_mallocz(avctx->extradata_size);
yading@11:     if (!p)
yading@11:         return AVERROR(ENOMEM);
yading@11:     oggstream->header[0] = p;
yading@11:     oggstream->header_len[0] = avctx->extradata_size;
yading@11:     bytestream_put_buffer(&p, avctx->extradata, avctx->extradata_size);
yading@11: 
yading@11:     /* second packet: VorbisComment */
yading@11:     p = ogg_write_vorbiscomment(8, bitexact, &oggstream->header_len[1], m, 0);
yading@11:     if (!p)
yading@11:         return AVERROR(ENOMEM);
yading@11:     oggstream->header[1] = p;
yading@11:     bytestream_put_buffer(&p, "OpusTags", 8);
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int ogg_write_header(AVFormatContext *s)
yading@11: {
yading@11:     OGGContext *ogg = s->priv_data;
yading@11:     OGGStreamContext *oggstream = NULL;
yading@11:     int i, j;
yading@11: 
yading@11:     if (ogg->pref_size)
yading@11:         av_log(s, AV_LOG_WARNING, "The pagesize option is deprecated\n");
yading@11: 
yading@11:     for (i = 0; i < s->nb_streams; i++) {
yading@11:         AVStream *st = s->streams[i];
yading@11:         unsigned serial_num = i;
yading@11: 
yading@11:         if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
yading@11:             if (st->codec->codec_id == AV_CODEC_ID_OPUS)
yading@11:                 /* Opus requires a fixed 48kHz clock */
yading@11:                 avpriv_set_pts_info(st, 64, 1, 48000);
yading@11:             else
yading@11:                 avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
yading@11:         } else if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO)
yading@11:             avpriv_set_pts_info(st, 64, st->codec->time_base.num, st->codec->time_base.den);
yading@11:         if (st->codec->codec_id != AV_CODEC_ID_VORBIS &&
yading@11:             st->codec->codec_id != AV_CODEC_ID_THEORA &&
yading@11:             st->codec->codec_id != AV_CODEC_ID_SPEEX  &&
yading@11:             st->codec->codec_id != AV_CODEC_ID_FLAC   &&
yading@11:             st->codec->codec_id != AV_CODEC_ID_OPUS) {
yading@11:             av_log(s, AV_LOG_ERROR, "Unsupported codec id in stream %d\n", i);
yading@11:             return -1;
yading@11:         }
yading@11: 
yading@11:         if (!st->codec->extradata || !st->codec->extradata_size) {
yading@11:             av_log(s, AV_LOG_ERROR, "No extradata present\n");
yading@11:             return -1;
yading@11:         }
yading@11:         oggstream = av_mallocz(sizeof(*oggstream));
yading@11:         oggstream->page.stream_index = i;
yading@11: 
yading@11:         if (!(st->codec->flags & CODEC_FLAG_BITEXACT))
yading@11:             do {
yading@11:                 serial_num = av_get_random_seed();
yading@11:                 for (j = 0; j < i; j++) {
yading@11:                     OGGStreamContext *sc = s->streams[j]->priv_data;
yading@11:                     if (serial_num == sc->serial_num)
yading@11:                         break;
yading@11:                 }
yading@11:             } while (j < i);
yading@11:         oggstream->serial_num = serial_num;
yading@11: 
yading@11:         st->priv_data = oggstream;
yading@11:         if (st->codec->codec_id == AV_CODEC_ID_FLAC) {
yading@11:             int err = ogg_build_flac_headers(st->codec, oggstream,
yading@11:                                              st->codec->flags & CODEC_FLAG_BITEXACT,
yading@11:                                              &s->metadata);
yading@11:             if (err) {
yading@11:                 av_log(s, AV_LOG_ERROR, "Error writing FLAC headers\n");
yading@11:                 av_freep(&st->priv_data);
yading@11:                 return err;
yading@11:             }
yading@11:         } else if (st->codec->codec_id == AV_CODEC_ID_SPEEX) {
yading@11:             int err = ogg_build_speex_headers(st->codec, oggstream,
yading@11:                                               st->codec->flags & CODEC_FLAG_BITEXACT,
yading@11:                                               &s->metadata);
yading@11:             if (err) {
yading@11:                 av_log(s, AV_LOG_ERROR, "Error writing Speex headers\n");
yading@11:                 av_freep(&st->priv_data);
yading@11:                 return err;
yading@11:             }
yading@11:         } else if (st->codec->codec_id == AV_CODEC_ID_OPUS) {
yading@11:             int err = ogg_build_opus_headers(st->codec, oggstream,
yading@11:                                              st->codec->flags & CODEC_FLAG_BITEXACT,
yading@11:                                              &s->metadata);
yading@11:             if (err) {
yading@11:                 av_log(s, AV_LOG_ERROR, "Error writing Opus headers\n");
yading@11:                 av_freep(&st->priv_data);
yading@11:                 return err;
yading@11:             }
yading@11:         } else {
yading@11:             uint8_t *p;
yading@11:             const char *cstr = st->codec->codec_id == AV_CODEC_ID_VORBIS ? "vorbis" : "theora";
yading@11:             int header_type = st->codec->codec_id == AV_CODEC_ID_VORBIS ? 3 : 0x81;
yading@11:             int framing_bit = st->codec->codec_id == AV_CODEC_ID_VORBIS ? 1 : 0;
yading@11: 
yading@11:             if (avpriv_split_xiph_headers(st->codec->extradata, st->codec->extradata_size,
yading@11:                                       st->codec->codec_id == AV_CODEC_ID_VORBIS ? 30 : 42,
yading@11:                                       oggstream->header, oggstream->header_len) < 0) {
yading@11:                 av_log(s, AV_LOG_ERROR, "Extradata corrupted\n");
yading@11:                 av_freep(&st->priv_data);
yading@11:                 return -1;
yading@11:             }
yading@11: 
yading@11:             p = ogg_write_vorbiscomment(7, st->codec->flags & CODEC_FLAG_BITEXACT,
yading@11:                                         &oggstream->header_len[1], &s->metadata,
yading@11:                                         framing_bit);
yading@11:             oggstream->header[1] = p;
yading@11:             if (!p)
yading@11:                 return AVERROR(ENOMEM);
yading@11: 
yading@11:             bytestream_put_byte(&p, header_type);
yading@11:             bytestream_put_buffer(&p, cstr, 6);
yading@11: 
yading@11:             if (st->codec->codec_id == AV_CODEC_ID_THEORA) {
yading@11:                 /** KFGSHIFT is the width of the less significant section of the granule position
yading@11:                     The less significant section is the frame count since the last keyframe */
yading@11:                 oggstream->kfgshift = ((oggstream->header[0][40]&3)<<3)|(oggstream->header[0][41]>>5);
yading@11:                 oggstream->vrev = oggstream->header[0][9];
yading@11:                 av_log(s, AV_LOG_DEBUG, "theora kfgshift %d, vrev %d\n",
yading@11:                        oggstream->kfgshift, oggstream->vrev);
yading@11:             }
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     for (j = 0; j < s->nb_streams; j++) {
yading@11:         OGGStreamContext *oggstream = s->streams[j]->priv_data;
yading@11:         ogg_buffer_data(s, s->streams[j], oggstream->header[0],
yading@11:                         oggstream->header_len[0], 0, 1);
yading@11:         oggstream->page.flags |= 2; // bos
yading@11:         ogg_buffer_page(s, oggstream);
yading@11:     }
yading@11:     for (j = 0; j < s->nb_streams; j++) {
yading@11:         AVStream *st = s->streams[j];
yading@11:         OGGStreamContext *oggstream = st->priv_data;
yading@11:         for (i = 1; i < 3; i++) {
yading@11:             if (oggstream->header_len[i])
yading@11:                 ogg_buffer_data(s, st, oggstream->header[i],
yading@11:                                 oggstream->header_len[i], 0, 1);
yading@11:         }
yading@11:         ogg_buffer_page(s, oggstream);
yading@11:     }
yading@11: 
yading@11:     oggstream->page.start_granule = AV_NOPTS_VALUE;
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static void ogg_write_pages(AVFormatContext *s, int flush)
yading@11: {
yading@11:     OGGContext *ogg = s->priv_data;
yading@11:     OGGPageList *next, *p;
yading@11: 
yading@11:     if (!ogg->page_list)
yading@11:         return;
yading@11: 
yading@11:     for (p = ogg->page_list; p; ) {
yading@11:         OGGStreamContext *oggstream =
yading@11:             s->streams[p->page.stream_index]->priv_data;
yading@11:         if (oggstream->page_count < 2 && !flush)
yading@11:             break;
yading@11:         ogg_write_page(s, &p->page,
yading@11:                        flush && oggstream->page_count == 1 ? 4 : 0); // eos
yading@11:         next = p->next;
yading@11:         av_freep(&p);
yading@11:         p = next;
yading@11:     }
yading@11:     ogg->page_list = p;
yading@11: }
yading@11: 
yading@11: static int ogg_write_packet(AVFormatContext *s, AVPacket *pkt)
yading@11: {
yading@11:     AVStream *st = s->streams[pkt->stream_index];
yading@11:     OGGStreamContext *oggstream = st->priv_data;
yading@11:     int ret;
yading@11:     int64_t granule;
yading@11: 
yading@11:     if (st->codec->codec_id == AV_CODEC_ID_THEORA) {
yading@11:         int64_t pts = oggstream->vrev < 1 ? pkt->pts : pkt->pts + pkt->duration;
yading@11:         int pframe_count;
yading@11:         if (pkt->flags & AV_PKT_FLAG_KEY)
yading@11:             oggstream->last_kf_pts = pts;
yading@11:         pframe_count = pts - oggstream->last_kf_pts;
yading@11:         // prevent frame count from overflow if key frame flag is not set
yading@11:         if (pframe_count >= (1<<oggstream->kfgshift)) {
yading@11:             oggstream->last_kf_pts += pframe_count;
yading@11:             pframe_count = 0;
yading@11:         }
yading@11:         granule = (oggstream->last_kf_pts<<oggstream->kfgshift) | pframe_count;
yading@11:     } else if (st->codec->codec_id == AV_CODEC_ID_OPUS)
yading@11:         granule = pkt->pts + pkt->duration + av_rescale_q(st->codec->delay, (AVRational){ 1, st->codec->sample_rate }, st->time_base);
yading@11:     else
yading@11:         granule = pkt->pts + pkt->duration;
yading@11: 
yading@11:     if (oggstream->page.start_granule == AV_NOPTS_VALUE)
yading@11:         oggstream->page.start_granule = pkt->pts;
yading@11: 
yading@11:     ret = ogg_buffer_data(s, st, pkt->data, pkt->size, granule, 0);
yading@11:     if (ret < 0)
yading@11:         return ret;
yading@11: 
yading@11:     ogg_write_pages(s, 0);
yading@11: 
yading@11:     oggstream->last_granule = granule;
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int ogg_write_trailer(AVFormatContext *s)
yading@11: {
yading@11:     int i;
yading@11: 
yading@11:     /* flush current page if needed */
yading@11:     for (i = 0; i < s->nb_streams; i++) {
yading@11:         OGGStreamContext *oggstream = s->streams[i]->priv_data;
yading@11: 
yading@11:         if (oggstream->page.size > 0)
yading@11:             ogg_buffer_page(s, oggstream);
yading@11:     }
yading@11: 
yading@11:     ogg_write_pages(s, 1);
yading@11: 
yading@11:     for (i = 0; i < s->nb_streams; i++) {
yading@11:         AVStream *st = s->streams[i];
yading@11:         OGGStreamContext *oggstream = st->priv_data;
yading@11:         if (st->codec->codec_id == AV_CODEC_ID_FLAC ||
yading@11:             st->codec->codec_id == AV_CODEC_ID_SPEEX ||
yading@11:             st->codec->codec_id == AV_CODEC_ID_OPUS) {
yading@11:             av_freep(&oggstream->header[0]);
yading@11:         }
yading@11:         av_freep(&oggstream->header[1]);
yading@11:         av_freep(&st->priv_data);
yading@11:     }
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: AVOutputFormat ff_ogg_muxer = {
yading@11:     .name              = "ogg",
yading@11:     .long_name         = NULL_IF_CONFIG_SMALL("Ogg"),
yading@11:     .mime_type         = "application/ogg",
yading@11:     .extensions        = "ogg,ogv,spx,opus",
yading@11:     .priv_data_size    = sizeof(OGGContext),
yading@11:     .audio_codec       = AV_CODEC_ID_FLAC,
yading@11:     .video_codec       = AV_CODEC_ID_THEORA,
yading@11:     .write_header      = ogg_write_header,
yading@11:     .write_packet      = ogg_write_packet,
yading@11:     .write_trailer     = ogg_write_trailer,
yading@11:     .priv_class        = &ogg_muxer_class,
yading@11: };