libavformat/oggenc.c
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00001 /*
00002  * Ogg muxer
00003  * Copyright (c) 2007 Baptiste Coudurier <baptiste dot coudurier at free dot fr>
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "libavutil/crc.h"
00023 #include "libavutil/opt.h"
00024 #include "libavutil/mathematics.h"
00025 #include "libavutil/random_seed.h"
00026 #include "libavcodec/xiph.h"
00027 #include "libavcodec/bytestream.h"
00028 #include "libavcodec/flac.h"
00029 #include "avformat.h"
00030 #include "avio_internal.h"
00031 #include "internal.h"
00032 #include "vorbiscomment.h"
00033 
00034 #define MAX_PAGE_SIZE 65025
00035 
00036 typedef struct {
00037     int64_t granule;
00038     int stream_index;
00039     uint8_t flags;
00040     uint8_t segments_count;
00041     uint8_t segments[255];
00042     uint8_t data[MAX_PAGE_SIZE];
00043     uint16_t size;
00044 } OGGPage;
00045 
00046 typedef struct {
00047     unsigned page_counter;
00048     uint8_t *header[3];
00049     int header_len[3];
00051     int kfgshift;
00052     int64_t last_kf_pts;
00053     int vrev;
00054     int eos;
00055     unsigned page_count; 
00056     OGGPage page; 
00057     unsigned serial_num; 
00058     int64_t last_granule; 
00059 } OGGStreamContext;
00060 
00061 typedef struct OGGPageList {
00062     OGGPage page;
00063     struct OGGPageList *next;
00064 } OGGPageList;
00065 
00066 typedef struct {
00067     const AVClass *class;
00068     OGGPageList *page_list;
00069     int pref_size; 
00070 } OGGContext;
00071 
00072 
00073 static const AVOption options[] = {
00074     { "oggpagesize", "Set preferred Ogg page size.",
00075       offsetof(OGGContext, pref_size), AV_OPT_TYPE_INT, {.dbl = 0}, 0, MAX_PAGE_SIZE, AV_OPT_FLAG_ENCODING_PARAM},
00076     { NULL },
00077 };
00078 
00079 static const AVClass ogg_muxer_class = {
00080     "Ogg muxer",
00081     av_default_item_name,
00082     options,
00083     LIBAVUTIL_VERSION_INT,
00084 };
00085 
00086 
00087 static void ogg_update_checksum(AVFormatContext *s, AVIOContext *pb, int64_t crc_offset)
00088 {
00089     int64_t pos = avio_tell(pb);
00090     uint32_t checksum = ffio_get_checksum(pb);
00091     avio_seek(pb, crc_offset, SEEK_SET);
00092     avio_wb32(pb, checksum);
00093     avio_seek(pb, pos, SEEK_SET);
00094 }
00095 
00096 static int ogg_write_page(AVFormatContext *s, OGGPage *page, int extra_flags)
00097 {
00098     OGGStreamContext *oggstream = s->streams[page->stream_index]->priv_data;
00099     AVIOContext *pb;
00100     int64_t crc_offset;
00101     int ret, size;
00102     uint8_t *buf;
00103 
00104     ret = avio_open_dyn_buf(&pb);
00105     if (ret < 0)
00106         return ret;
00107     ffio_init_checksum(pb, ff_crc04C11DB7_update, 0);
00108     ffio_wfourcc(pb, "OggS");
00109     avio_w8(pb, 0);
00110     avio_w8(pb, page->flags | extra_flags);
00111     avio_wl64(pb, page->granule);
00112     avio_wl32(pb, oggstream->serial_num);
00113     avio_wl32(pb, oggstream->page_counter++);
00114     crc_offset = avio_tell(pb);
00115     avio_wl32(pb, 0); // crc
00116     avio_w8(pb, page->segments_count);
00117     avio_write(pb, page->segments, page->segments_count);
00118     avio_write(pb, page->data, page->size);
00119 
00120     ogg_update_checksum(s, pb, crc_offset);
00121     avio_flush(pb);
00122 
00123     size = avio_close_dyn_buf(pb, &buf);
00124     if (size < 0)
00125         return size;
00126 
00127     avio_write(s->pb, buf, size);
00128     avio_flush(s->pb);
00129     av_free(buf);
00130     oggstream->page_count--;
00131     return 0;
00132 }
00133 
00134 static int64_t ogg_granule_to_timestamp(OGGStreamContext *oggstream, int64_t granule)
00135 {
00136     if (oggstream->kfgshift)
00137         return (granule>>oggstream->kfgshift) +
00138             (granule & ((1<<oggstream->kfgshift)-1));
00139     else
00140         return granule;
00141 }
00142 
00143 static int ogg_compare_granule(AVFormatContext *s, OGGPage *next, OGGPage *page)
00144 {
00145     AVStream *st2 = s->streams[next->stream_index];
00146     AVStream *st  = s->streams[page->stream_index];
00147     int64_t next_granule, cur_granule;
00148 
00149     if (next->granule == -1 || page->granule == -1)
00150         return 0;
00151 
00152     next_granule = av_rescale_q(ogg_granule_to_timestamp(st2->priv_data, next->granule),
00153                                 st2->time_base, AV_TIME_BASE_Q);
00154     cur_granule  = av_rescale_q(ogg_granule_to_timestamp(st->priv_data, page->granule),
00155                                 st ->time_base, AV_TIME_BASE_Q);
00156     return next_granule > cur_granule;
00157 }
00158 
00159 static int ogg_reset_cur_page(OGGStreamContext *oggstream)
00160 {
00161     oggstream->page.granule = -1;
00162     oggstream->page.flags = 0;
00163     oggstream->page.segments_count = 0;
00164     oggstream->page.size = 0;
00165     return 0;
00166 }
00167 
00168 static int ogg_buffer_page(AVFormatContext *s, OGGStreamContext *oggstream)
00169 {
00170     OGGContext *ogg = s->priv_data;
00171     OGGPageList **p = &ogg->page_list;
00172     OGGPageList *l = av_mallocz(sizeof(*l));
00173 
00174     if (!l)
00175         return AVERROR(ENOMEM);
00176     l->page = oggstream->page;
00177 
00178     oggstream->page_count++;
00179     ogg_reset_cur_page(oggstream);
00180 
00181     while (*p) {
00182         if (ogg_compare_granule(s, &(*p)->page, &l->page))
00183             break;
00184         p = &(*p)->next;
00185     }
00186     l->next = *p;
00187     *p = l;
00188 
00189     return 0;
00190 }
00191 
00192 static int ogg_buffer_data(AVFormatContext *s, AVStream *st,
00193                            uint8_t *data, unsigned size, int64_t granule)
00194 {
00195     OGGStreamContext *oggstream = st->priv_data;
00196     OGGContext *ogg = s->priv_data;
00197     int total_segments = size / 255 + 1;
00198     uint8_t *p = data;
00199     int i, segments, len, flush = 0;
00200 
00201     // Handles VFR by flushing page because this frame needs to have a timestamp
00202     if (st->codec->codec_id == CODEC_ID_THEORA &&
00203         ogg_granule_to_timestamp(oggstream, granule) >
00204         ogg_granule_to_timestamp(oggstream, oggstream->last_granule) + 1) {
00205         if (oggstream->page.granule != -1)
00206             ogg_buffer_page(s, oggstream);
00207         flush = 1;
00208     }
00209 
00210     for (i = 0; i < total_segments; ) {
00211         OGGPage *page = &oggstream->page;
00212 
00213         segments = FFMIN(total_segments - i, 255 - page->segments_count);
00214 
00215         if (i && !page->segments_count)
00216             page->flags |= 1; // continued packet
00217 
00218         memset(page->segments+page->segments_count, 255, segments - 1);
00219         page->segments_count += segments - 1;
00220 
00221         len = FFMIN(size, segments*255);
00222         page->segments[page->segments_count++] = len - (segments-1)*255;
00223         memcpy(page->data+page->size, p, len);
00224         p += len;
00225         size -= len;
00226         i += segments;
00227         page->size += len;
00228 
00229         if (i == total_segments)
00230             page->granule = granule;
00231 
00232         if(page->segments_count == 255 ||
00233            (ogg->pref_size > 0 && page->size >= ogg->pref_size)) {
00234            ogg_buffer_page(s, oggstream);
00235         }
00236     }
00237 
00238     if (flush && oggstream->page.granule != -1)
00239         ogg_buffer_page(s, oggstream);
00240 
00241     return 0;
00242 }
00243 
00244 static uint8_t *ogg_write_vorbiscomment(int offset, int bitexact,
00245                                         int *header_len, AVDictionary **m, int framing_bit)
00246 {
00247     const char *vendor = bitexact ? "ffmpeg" : LIBAVFORMAT_IDENT;
00248     int size;
00249     uint8_t *p, *p0;
00250     unsigned int count;
00251 
00252     ff_metadata_conv(m, ff_vorbiscomment_metadata_conv, NULL);
00253 
00254     size = offset + ff_vorbiscomment_length(*m, vendor, &count) + framing_bit;
00255     p = av_mallocz(size);
00256     if (!p)
00257         return NULL;
00258     p0 = p;
00259 
00260     p += offset;
00261     ff_vorbiscomment_write(&p, m, vendor, count);
00262     if (framing_bit)
00263         bytestream_put_byte(&p, 1);
00264 
00265     *header_len = size;
00266     return p0;
00267 }
00268 
00269 static int ogg_build_flac_headers(AVCodecContext *avctx,
00270                                   OGGStreamContext *oggstream, int bitexact,
00271                                   AVDictionary **m)
00272 {
00273     enum FLACExtradataFormat format;
00274     uint8_t *streaminfo;
00275     uint8_t *p;
00276 
00277     if (!avpriv_flac_is_extradata_valid(avctx, &format, &streaminfo))
00278         return -1;
00279 
00280     // first packet: STREAMINFO
00281     oggstream->header_len[0] = 51;
00282     oggstream->header[0] = av_mallocz(51); // per ogg flac specs
00283     p = oggstream->header[0];
00284     if (!p)
00285         return AVERROR(ENOMEM);
00286     bytestream_put_byte(&p, 0x7F);
00287     bytestream_put_buffer(&p, "FLAC", 4);
00288     bytestream_put_byte(&p, 1); // major version
00289     bytestream_put_byte(&p, 0); // minor version
00290     bytestream_put_be16(&p, 1); // headers packets without this one
00291     bytestream_put_buffer(&p, "fLaC", 4);
00292     bytestream_put_byte(&p, 0x00); // streaminfo
00293     bytestream_put_be24(&p, 34);
00294     bytestream_put_buffer(&p, streaminfo, FLAC_STREAMINFO_SIZE);
00295 
00296     // second packet: VorbisComment
00297     p = ogg_write_vorbiscomment(4, bitexact, &oggstream->header_len[1], m, 0);
00298     if (!p)
00299         return AVERROR(ENOMEM);
00300     oggstream->header[1] = p;
00301     bytestream_put_byte(&p, 0x84); // last metadata block and vorbis comment
00302     bytestream_put_be24(&p, oggstream->header_len[1] - 4);
00303 
00304     return 0;
00305 }
00306 
00307 #define SPEEX_HEADER_SIZE 80
00308 
00309 static int ogg_build_speex_headers(AVCodecContext *avctx,
00310                                    OGGStreamContext *oggstream, int bitexact,
00311                                    AVDictionary **m)
00312 {
00313     uint8_t *p;
00314 
00315     if (avctx->extradata_size < SPEEX_HEADER_SIZE)
00316         return -1;
00317 
00318     // first packet: Speex header
00319     p = av_mallocz(SPEEX_HEADER_SIZE);
00320     if (!p)
00321         return AVERROR(ENOMEM);
00322     oggstream->header[0] = p;
00323     oggstream->header_len[0] = SPEEX_HEADER_SIZE;
00324     bytestream_put_buffer(&p, avctx->extradata, SPEEX_HEADER_SIZE);
00325     AV_WL32(&oggstream->header[0][68], 0);  // set extra_headers to 0
00326 
00327     // second packet: VorbisComment
00328     p = ogg_write_vorbiscomment(0, bitexact, &oggstream->header_len[1], m, 0);
00329     if (!p)
00330         return AVERROR(ENOMEM);
00331     oggstream->header[1] = p;
00332 
00333     return 0;
00334 }
00335 
00336 static int ogg_write_header(AVFormatContext *s)
00337 {
00338     OGGStreamContext *oggstream;
00339     int i, j;
00340 
00341     for (i = 0; i < s->nb_streams; i++) {
00342         AVStream *st = s->streams[i];
00343         unsigned serial_num = i;
00344 
00345         if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO)
00346             avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
00347         else if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO)
00348             avpriv_set_pts_info(st, 64, st->codec->time_base.num, st->codec->time_base.den);
00349         if (st->codec->codec_id != CODEC_ID_VORBIS &&
00350             st->codec->codec_id != CODEC_ID_THEORA &&
00351             st->codec->codec_id != CODEC_ID_SPEEX  &&
00352             st->codec->codec_id != CODEC_ID_FLAC) {
00353             av_log(s, AV_LOG_ERROR, "Unsupported codec id in stream %d\n", i);
00354             return -1;
00355         }
00356 
00357         if (!st->codec->extradata || !st->codec->extradata_size) {
00358             av_log(s, AV_LOG_ERROR, "No extradata present\n");
00359             return -1;
00360         }
00361         oggstream = av_mallocz(sizeof(*oggstream));
00362         oggstream->page.stream_index = i;
00363 
00364         if (!(st->codec->flags & CODEC_FLAG_BITEXACT))
00365             do {
00366                 serial_num = av_get_random_seed();
00367                 for (j = 0; j < i; j++) {
00368                     OGGStreamContext *sc = s->streams[j]->priv_data;
00369                     if (serial_num == sc->serial_num)
00370                         break;
00371                 }
00372             } while (j < i);
00373         oggstream->serial_num = serial_num;
00374 
00375         st->priv_data = oggstream;
00376         if (st->codec->codec_id == CODEC_ID_FLAC) {
00377             int err = ogg_build_flac_headers(st->codec, oggstream,
00378                                              st->codec->flags & CODEC_FLAG_BITEXACT,
00379                                              &s->metadata);
00380             if (err) {
00381                 av_log(s, AV_LOG_ERROR, "Error writing FLAC headers\n");
00382                 av_freep(&st->priv_data);
00383                 return err;
00384             }
00385         } else if (st->codec->codec_id == CODEC_ID_SPEEX) {
00386             int err = ogg_build_speex_headers(st->codec, oggstream,
00387                                               st->codec->flags & CODEC_FLAG_BITEXACT,
00388                                               &s->metadata);
00389             if (err) {
00390                 av_log(s, AV_LOG_ERROR, "Error writing Speex headers\n");
00391                 av_freep(&st->priv_data);
00392                 return err;
00393             }
00394         } else {
00395             uint8_t *p;
00396             const char *cstr = st->codec->codec_id == CODEC_ID_VORBIS ? "vorbis" : "theora";
00397             int header_type = st->codec->codec_id == CODEC_ID_VORBIS ? 3 : 0x81;
00398             int framing_bit = st->codec->codec_id == CODEC_ID_VORBIS ? 1 : 0;
00399 
00400             if (avpriv_split_xiph_headers(st->codec->extradata, st->codec->extradata_size,
00401                                       st->codec->codec_id == CODEC_ID_VORBIS ? 30 : 42,
00402                                       oggstream->header, oggstream->header_len) < 0) {
00403                 av_log(s, AV_LOG_ERROR, "Extradata corrupted\n");
00404                 av_freep(&st->priv_data);
00405                 return -1;
00406             }
00407 
00408             p = ogg_write_vorbiscomment(7, st->codec->flags & CODEC_FLAG_BITEXACT,
00409                                         &oggstream->header_len[1], &s->metadata,
00410                                         framing_bit);
00411             if (!p)
00412                 return AVERROR(ENOMEM);
00413 
00414             oggstream->header[1] = p;
00415             bytestream_put_byte(&p, header_type);
00416             bytestream_put_buffer(&p, cstr, 6);
00417 
00418             if (st->codec->codec_id == CODEC_ID_THEORA) {
00421                 oggstream->kfgshift = ((oggstream->header[0][40]&3)<<3)|(oggstream->header[0][41]>>5);
00422                 oggstream->vrev = oggstream->header[0][9];
00423                 av_log(s, AV_LOG_DEBUG, "theora kfgshift %d, vrev %d\n",
00424                        oggstream->kfgshift, oggstream->vrev);
00425             }
00426         }
00427     }
00428 
00429     for (j = 0; j < s->nb_streams; j++) {
00430         OGGStreamContext *oggstream = s->streams[j]->priv_data;
00431         ogg_buffer_data(s, s->streams[j], oggstream->header[0],
00432                         oggstream->header_len[0], 0);
00433         oggstream->page.flags |= 2; // bos
00434         ogg_buffer_page(s, oggstream);
00435     }
00436     for (j = 0; j < s->nb_streams; j++) {
00437         AVStream *st = s->streams[j];
00438         OGGStreamContext *oggstream = st->priv_data;
00439         for (i = 1; i < 3; i++) {
00440             if (oggstream && oggstream->header_len[i])
00441                 ogg_buffer_data(s, st, oggstream->header[i],
00442                                 oggstream->header_len[i], 0);
00443         }
00444         ogg_buffer_page(s, oggstream);
00445     }
00446     return 0;
00447 }
00448 
00449 static void ogg_write_pages(AVFormatContext *s, int flush)
00450 {
00451     OGGContext *ogg = s->priv_data;
00452     OGGPageList *next, *p;
00453 
00454     if (!ogg->page_list)
00455         return;
00456 
00457     for (p = ogg->page_list; p; ) {
00458         OGGStreamContext *oggstream =
00459             s->streams[p->page.stream_index]->priv_data;
00460         if (oggstream->page_count < 2 && !flush)
00461             break;
00462         ogg_write_page(s, &p->page,
00463                        flush && oggstream->page_count == 1 ? 4 : 0); // eos
00464         next = p->next;
00465         av_freep(&p);
00466         p = next;
00467     }
00468     ogg->page_list = p;
00469 }
00470 
00471 static int ogg_write_packet(AVFormatContext *s, AVPacket *pkt)
00472 {
00473     AVStream *st = s->streams[pkt->stream_index];
00474     OGGStreamContext *oggstream = st->priv_data;
00475     int ret;
00476     int64_t granule;
00477 
00478     if (st->codec->codec_id == CODEC_ID_THEORA) {
00479         int64_t pts = oggstream->vrev < 1 ? pkt->pts : pkt->pts + pkt->duration;
00480         int pframe_count;
00481         if (pkt->flags & AV_PKT_FLAG_KEY)
00482             oggstream->last_kf_pts = pts;
00483         pframe_count = pts - oggstream->last_kf_pts;
00484         // prevent frame count from overflow if key frame flag is not set
00485         if (pframe_count >= (1<<oggstream->kfgshift)) {
00486             oggstream->last_kf_pts += pframe_count;
00487             pframe_count = 0;
00488         }
00489         granule = (oggstream->last_kf_pts<<oggstream->kfgshift) | pframe_count;
00490     } else
00491         granule = pkt->pts + pkt->duration;
00492 
00493     ret = ogg_buffer_data(s, st, pkt->data, pkt->size, granule);
00494     if (ret < 0)
00495         return ret;
00496 
00497     ogg_write_pages(s, 0);
00498 
00499     oggstream->last_granule = granule;
00500 
00501     return 0;
00502 }
00503 
00504 static int ogg_write_trailer(AVFormatContext *s)
00505 {
00506     int i;
00507 
00508     /* flush current page */
00509     for (i = 0; i < s->nb_streams; i++)
00510         ogg_buffer_page(s, s->streams[i]->priv_data);
00511 
00512     ogg_write_pages(s, 1);
00513 
00514     for (i = 0; i < s->nb_streams; i++) {
00515         AVStream *st = s->streams[i];
00516         OGGStreamContext *oggstream = st->priv_data;
00517         if (st->codec->codec_id == CODEC_ID_FLAC ||
00518             st->codec->codec_id == CODEC_ID_SPEEX) {
00519             av_freep(&oggstream->header[0]);
00520             av_freep(&oggstream->header[1]);
00521         }
00522         else
00523             av_freep(&oggstream->header[1]);
00524         av_freep(&st->priv_data);
00525     }
00526     return 0;
00527 }
00528 
00529 AVOutputFormat ff_ogg_muxer = {
00530     .name              = "ogg",
00531     .long_name         = NULL_IF_CONFIG_SMALL("Ogg"),
00532     .mime_type         = "application/ogg",
00533     .extensions        = "ogg,ogv,spx",
00534     .priv_data_size    = sizeof(OGGContext),
00535     .audio_codec       = CODEC_ID_FLAC,
00536     .video_codec       = CODEC_ID_THEORA,
00537     .write_header      = ogg_write_header,
00538     .write_packet      = ogg_write_packet,
00539     .write_trailer     = ogg_write_trailer,
00540     .priv_class = &ogg_muxer_class,
00541 };