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libavformat/matroskaenc.c

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00001 /*
00002  * Matroska muxer
00003  * Copyright (c) 2007 David Conrad
00004  *
00005  * This file is part of Libav.
00006  *
00007  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "avformat.h"
00023 #include "internal.h"
00024 #include "riff.h"
00025 #include "isom.h"
00026 #include "matroska.h"
00027 #include "avc.h"
00028 #include "flacenc.h"
00029 #include "avlanguage.h"
00030 #include "libavutil/samplefmt.h"
00031 #include "libavutil/intreadwrite.h"
00032 #include "libavutil/intfloat.h"
00033 #include "libavutil/mathematics.h"
00034 #include "libavutil/random_seed.h"
00035 #include "libavutil/lfg.h"
00036 #include "libavutil/dict.h"
00037 #include "libavutil/avstring.h"
00038 #include "libavcodec/xiph.h"
00039 #include "libavcodec/mpeg4audio.h"
00040 
00041 typedef struct ebml_master {
00042     int64_t         pos;                
00043     int             sizebytes;          
00044 } ebml_master;
00045 
00046 typedef struct mkv_seekhead_entry {
00047     unsigned int    elementid;
00048     uint64_t        segmentpos;
00049 } mkv_seekhead_entry;
00050 
00051 typedef struct mkv_seekhead {
00052     int64_t                 filepos;
00053     int64_t                 segment_offset;     
00054     int                     reserved_size;      
00055     int                     max_entries;
00056     mkv_seekhead_entry      *entries;
00057     int                     num_entries;
00058 } mkv_seekhead;
00059 
00060 typedef struct {
00061     uint64_t        pts;
00062     int             tracknum;
00063     int64_t         cluster_pos;        
00064 } mkv_cuepoint;
00065 
00066 typedef struct {
00067     int64_t         segment_offset;
00068     mkv_cuepoint    *entries;
00069     int             num_entries;
00070 } mkv_cues;
00071 
00072 typedef struct {
00073     int             write_dts;
00074 } mkv_track;
00075 
00076 #define MODE_MATROSKAv2 0x01
00077 #define MODE_WEBM       0x02
00078 
00079 typedef struct MatroskaMuxContext {
00080     int             mode;
00081     AVIOContext   *dyn_bc;
00082     ebml_master     segment;
00083     int64_t         segment_offset;
00084     ebml_master     cluster;
00085     int64_t         cluster_pos;        
00086     int64_t         cluster_pts;
00087     int64_t         duration_offset;
00088     int64_t         duration;
00089     mkv_seekhead    *main_seekhead;
00090     mkv_cues        *cues;
00091     mkv_track       *tracks;
00092 
00093     unsigned int    audio_buffer_size;
00094     AVPacket        cur_audio_pkt;
00095 
00096     int have_attachments;
00097 } MatroskaMuxContext;
00098 
00099 
00102 #define MAX_SEEKENTRY_SIZE 21
00103 
00106 #define MAX_CUETRACKPOS_SIZE 22
00107 
00109 #define MAX_CUEPOINT_SIZE(num_tracks) 12 + MAX_CUETRACKPOS_SIZE*num_tracks
00110 
00111 
00112 static int ebml_id_size(unsigned int id)
00113 {
00114     return (av_log2(id+1)-1)/7+1;
00115 }
00116 
00117 static void put_ebml_id(AVIOContext *pb, unsigned int id)
00118 {
00119     int i = ebml_id_size(id);
00120     while (i--)
00121         avio_w8(pb, id >> (i*8));
00122 }
00123 
00129 static void put_ebml_size_unknown(AVIOContext *pb, int bytes)
00130 {
00131     assert(bytes <= 8);
00132     avio_w8(pb, 0x1ff >> bytes);
00133     while (--bytes)
00134         avio_w8(pb, 0xff);
00135 }
00136 
00140 static int ebml_num_size(uint64_t num)
00141 {
00142     int bytes = 1;
00143     while ((num+1) >> bytes*7) bytes++;
00144     return bytes;
00145 }
00146 
00153 static void put_ebml_num(AVIOContext *pb, uint64_t num, int bytes)
00154 {
00155     int i, needed_bytes = ebml_num_size(num);
00156 
00157     // sizes larger than this are currently undefined in EBML
00158     assert(num < (1ULL<<56)-1);
00159 
00160     if (bytes == 0)
00161         // don't care how many bytes are used, so use the min
00162         bytes = needed_bytes;
00163     // the bytes needed to write the given size would exceed the bytes
00164     // that we need to use, so write unknown size. This shouldn't happen.
00165     assert(bytes >= needed_bytes);
00166 
00167     num |= 1ULL << bytes*7;
00168     for (i = bytes - 1; i >= 0; i--)
00169         avio_w8(pb, num >> i*8);
00170 }
00171 
00172 static void put_ebml_uint(AVIOContext *pb, unsigned int elementid, uint64_t val)
00173 {
00174     int i, bytes = 1;
00175     uint64_t tmp = val;
00176     while (tmp>>=8) bytes++;
00177 
00178     put_ebml_id(pb, elementid);
00179     put_ebml_num(pb, bytes, 0);
00180     for (i = bytes - 1; i >= 0; i--)
00181         avio_w8(pb, val >> i*8);
00182 }
00183 
00184 static void put_ebml_float(AVIOContext *pb, unsigned int elementid, double val)
00185 {
00186     put_ebml_id(pb, elementid);
00187     put_ebml_num(pb, 8, 0);
00188     avio_wb64(pb, av_double2int(val));
00189 }
00190 
00191 static void put_ebml_binary(AVIOContext *pb, unsigned int elementid,
00192                             const void *buf, int size)
00193 {
00194     put_ebml_id(pb, elementid);
00195     put_ebml_num(pb, size, 0);
00196     avio_write(pb, buf, size);
00197 }
00198 
00199 static void put_ebml_string(AVIOContext *pb, unsigned int elementid, const char *str)
00200 {
00201     put_ebml_binary(pb, elementid, str, strlen(str));
00202 }
00203 
00210 static void put_ebml_void(AVIOContext *pb, uint64_t size)
00211 {
00212     int64_t currentpos = avio_tell(pb);
00213 
00214     assert(size >= 2);
00215 
00216     put_ebml_id(pb, EBML_ID_VOID);
00217     // we need to subtract the length needed to store the size from the
00218     // size we need to reserve so 2 cases, we use 8 bytes to store the
00219     // size if possible, 1 byte otherwise
00220     if (size < 10)
00221         put_ebml_num(pb, size-1, 0);
00222     else
00223         put_ebml_num(pb, size-9, 8);
00224     while(avio_tell(pb) < currentpos + size)
00225         avio_w8(pb, 0);
00226 }
00227 
00228 static ebml_master start_ebml_master(AVIOContext *pb, unsigned int elementid, uint64_t expectedsize)
00229 {
00230     int bytes = expectedsize ? ebml_num_size(expectedsize) : 8;
00231     put_ebml_id(pb, elementid);
00232     put_ebml_size_unknown(pb, bytes);
00233     return (ebml_master){ avio_tell(pb), bytes };
00234 }
00235 
00236 static void end_ebml_master(AVIOContext *pb, ebml_master master)
00237 {
00238     int64_t pos = avio_tell(pb);
00239 
00240     if (avio_seek(pb, master.pos - master.sizebytes, SEEK_SET) < 0)
00241         return;
00242     put_ebml_num(pb, pos - master.pos, master.sizebytes);
00243     avio_seek(pb, pos, SEEK_SET);
00244 }
00245 
00246 static void put_xiph_size(AVIOContext *pb, int size)
00247 {
00248     int i;
00249     for (i = 0; i < size / 255; i++)
00250         avio_w8(pb, 255);
00251     avio_w8(pb, size % 255);
00252 }
00253 
00265 static mkv_seekhead * mkv_start_seekhead(AVIOContext *pb, int64_t segment_offset, int numelements)
00266 {
00267     mkv_seekhead *new_seekhead = av_mallocz(sizeof(mkv_seekhead));
00268     if (new_seekhead == NULL)
00269         return NULL;
00270 
00271     new_seekhead->segment_offset = segment_offset;
00272 
00273     if (numelements > 0) {
00274         new_seekhead->filepos = avio_tell(pb);
00275         // 21 bytes max for a seek entry, 10 bytes max for the SeekHead ID
00276         // and size, and 3 bytes to guarantee that an EBML void element
00277         // will fit afterwards
00278         new_seekhead->reserved_size = numelements * MAX_SEEKENTRY_SIZE + 13;
00279         new_seekhead->max_entries = numelements;
00280         put_ebml_void(pb, new_seekhead->reserved_size);
00281     }
00282     return new_seekhead;
00283 }
00284 
00285 static int mkv_add_seekhead_entry(mkv_seekhead *seekhead, unsigned int elementid, uint64_t filepos)
00286 {
00287     mkv_seekhead_entry *entries = seekhead->entries;
00288 
00289     // don't store more elements than we reserved space for
00290     if (seekhead->max_entries > 0 && seekhead->max_entries <= seekhead->num_entries)
00291         return -1;
00292 
00293     entries = av_realloc(entries, (seekhead->num_entries + 1) * sizeof(mkv_seekhead_entry));
00294     if (entries == NULL)
00295         return AVERROR(ENOMEM);
00296 
00297     entries[seekhead->num_entries  ].elementid = elementid;
00298     entries[seekhead->num_entries++].segmentpos = filepos - seekhead->segment_offset;
00299 
00300     seekhead->entries = entries;
00301     return 0;
00302 }
00303 
00313 static int64_t mkv_write_seekhead(AVIOContext *pb, mkv_seekhead *seekhead)
00314 {
00315     ebml_master metaseek, seekentry;
00316     int64_t currentpos;
00317     int i;
00318 
00319     currentpos = avio_tell(pb);
00320 
00321     if (seekhead->reserved_size > 0) {
00322         if (avio_seek(pb, seekhead->filepos, SEEK_SET) < 0) {
00323             currentpos = -1;
00324             goto fail;
00325         }
00326     }
00327 
00328     metaseek = start_ebml_master(pb, MATROSKA_ID_SEEKHEAD, seekhead->reserved_size);
00329     for (i = 0; i < seekhead->num_entries; i++) {
00330         mkv_seekhead_entry *entry = &seekhead->entries[i];
00331 
00332         seekentry = start_ebml_master(pb, MATROSKA_ID_SEEKENTRY, MAX_SEEKENTRY_SIZE);
00333 
00334         put_ebml_id(pb, MATROSKA_ID_SEEKID);
00335         put_ebml_num(pb, ebml_id_size(entry->elementid), 0);
00336         put_ebml_id(pb, entry->elementid);
00337 
00338         put_ebml_uint(pb, MATROSKA_ID_SEEKPOSITION, entry->segmentpos);
00339         end_ebml_master(pb, seekentry);
00340     }
00341     end_ebml_master(pb, metaseek);
00342 
00343     if (seekhead->reserved_size > 0) {
00344         uint64_t remaining = seekhead->filepos + seekhead->reserved_size - avio_tell(pb);
00345         put_ebml_void(pb, remaining);
00346         avio_seek(pb, currentpos, SEEK_SET);
00347 
00348         currentpos = seekhead->filepos;
00349     }
00350 fail:
00351     av_free(seekhead->entries);
00352     av_free(seekhead);
00353 
00354     return currentpos;
00355 }
00356 
00357 static mkv_cues * mkv_start_cues(int64_t segment_offset)
00358 {
00359     mkv_cues *cues = av_mallocz(sizeof(mkv_cues));
00360     if (cues == NULL)
00361         return NULL;
00362 
00363     cues->segment_offset = segment_offset;
00364     return cues;
00365 }
00366 
00367 static int mkv_add_cuepoint(mkv_cues *cues, int stream, int64_t ts, int64_t cluster_pos)
00368 {
00369     mkv_cuepoint *entries = cues->entries;
00370 
00371     entries = av_realloc(entries, (cues->num_entries + 1) * sizeof(mkv_cuepoint));
00372     if (entries == NULL)
00373         return AVERROR(ENOMEM);
00374 
00375     if (ts < 0)
00376         return 0;
00377 
00378     entries[cues->num_entries  ].pts = ts;
00379     entries[cues->num_entries  ].tracknum = stream + 1;
00380     entries[cues->num_entries++].cluster_pos = cluster_pos - cues->segment_offset;
00381 
00382     cues->entries = entries;
00383     return 0;
00384 }
00385 
00386 static int64_t mkv_write_cues(AVIOContext *pb, mkv_cues *cues, int num_tracks)
00387 {
00388     ebml_master cues_element;
00389     int64_t currentpos;
00390     int i, j;
00391 
00392     currentpos = avio_tell(pb);
00393     cues_element = start_ebml_master(pb, MATROSKA_ID_CUES, 0);
00394 
00395     for (i = 0; i < cues->num_entries; i++) {
00396         ebml_master cuepoint, track_positions;
00397         mkv_cuepoint *entry = &cues->entries[i];
00398         uint64_t pts = entry->pts;
00399 
00400         cuepoint = start_ebml_master(pb, MATROSKA_ID_POINTENTRY, MAX_CUEPOINT_SIZE(num_tracks));
00401         put_ebml_uint(pb, MATROSKA_ID_CUETIME, pts);
00402 
00403         // put all the entries from different tracks that have the exact same
00404         // timestamp into the same CuePoint
00405         for (j = 0; j < cues->num_entries - i && entry[j].pts == pts; j++) {
00406             track_positions = start_ebml_master(pb, MATROSKA_ID_CUETRACKPOSITION, MAX_CUETRACKPOS_SIZE);
00407             put_ebml_uint(pb, MATROSKA_ID_CUETRACK          , entry[j].tracknum   );
00408             put_ebml_uint(pb, MATROSKA_ID_CUECLUSTERPOSITION, entry[j].cluster_pos);
00409             end_ebml_master(pb, track_positions);
00410         }
00411         i += j - 1;
00412         end_ebml_master(pb, cuepoint);
00413     }
00414     end_ebml_master(pb, cues_element);
00415 
00416     return currentpos;
00417 }
00418 
00419 static int put_xiph_codecpriv(AVFormatContext *s, AVIOContext *pb, AVCodecContext *codec)
00420 {
00421     uint8_t *header_start[3];
00422     int header_len[3];
00423     int first_header_size;
00424     int j;
00425 
00426     if (codec->codec_id == CODEC_ID_VORBIS)
00427         first_header_size = 30;
00428     else
00429         first_header_size = 42;
00430 
00431     if (avpriv_split_xiph_headers(codec->extradata, codec->extradata_size,
00432                               first_header_size, header_start, header_len) < 0) {
00433         av_log(s, AV_LOG_ERROR, "Extradata corrupt.\n");
00434         return -1;
00435     }
00436 
00437     avio_w8(pb, 2);                    // number packets - 1
00438     for (j = 0; j < 2; j++) {
00439         put_xiph_size(pb, header_len[j]);
00440     }
00441     for (j = 0; j < 3; j++)
00442         avio_write(pb, header_start[j], header_len[j]);
00443 
00444     return 0;
00445 }
00446 
00447 static void get_aac_sample_rates(AVFormatContext *s, AVCodecContext *codec, int *sample_rate, int *output_sample_rate)
00448 {
00449     MPEG4AudioConfig mp4ac;
00450 
00451     if (avpriv_mpeg4audio_get_config(&mp4ac, codec->extradata,
00452                                      codec->extradata_size * 8, 1) < 0) {
00453         av_log(s, AV_LOG_WARNING, "Error parsing AAC extradata, unable to determine samplerate.\n");
00454         return;
00455     }
00456 
00457     *sample_rate        = mp4ac.sample_rate;
00458     *output_sample_rate = mp4ac.ext_sample_rate;
00459 }
00460 
00461 static int mkv_write_codecprivate(AVFormatContext *s, AVIOContext *pb, AVCodecContext *codec, int native_id, int qt_id)
00462 {
00463     AVIOContext *dyn_cp;
00464     uint8_t *codecpriv;
00465     int ret, codecpriv_size;
00466 
00467     ret = avio_open_dyn_buf(&dyn_cp);
00468     if(ret < 0)
00469         return ret;
00470 
00471     if (native_id) {
00472         if (codec->codec_id == CODEC_ID_VORBIS || codec->codec_id == CODEC_ID_THEORA)
00473             ret = put_xiph_codecpriv(s, dyn_cp, codec);
00474         else if (codec->codec_id == CODEC_ID_FLAC)
00475             ret = ff_flac_write_header(dyn_cp, codec, 1);
00476         else if (codec->codec_id == CODEC_ID_H264)
00477             ret = ff_isom_write_avcc(dyn_cp, codec->extradata, codec->extradata_size);
00478         else if (codec->extradata_size)
00479             avio_write(dyn_cp, codec->extradata, codec->extradata_size);
00480     } else if (codec->codec_type == AVMEDIA_TYPE_VIDEO) {
00481         if (qt_id) {
00482             if (!codec->codec_tag)
00483                 codec->codec_tag = ff_codec_get_tag(codec_movvideo_tags, codec->codec_id);
00484             if (codec->extradata_size)
00485                 avio_write(dyn_cp, codec->extradata, codec->extradata_size);
00486         } else {
00487             if (!codec->codec_tag)
00488                 codec->codec_tag = ff_codec_get_tag(ff_codec_bmp_tags, codec->codec_id);
00489             if (!codec->codec_tag) {
00490                 av_log(s, AV_LOG_ERROR, "No bmp codec ID found.\n");
00491                 ret = -1;
00492             }
00493 
00494             ff_put_bmp_header(dyn_cp, codec, ff_codec_bmp_tags, 0);
00495         }
00496 
00497     } else if (codec->codec_type == AVMEDIA_TYPE_AUDIO) {
00498         unsigned int tag;
00499         tag = ff_codec_get_tag(ff_codec_wav_tags, codec->codec_id);
00500         if (!tag) {
00501             av_log(s, AV_LOG_ERROR, "No wav codec ID found.\n");
00502             ret = -1;
00503         }
00504         if (!codec->codec_tag)
00505             codec->codec_tag = tag;
00506 
00507         ff_put_wav_header(dyn_cp, codec);
00508     }
00509 
00510     codecpriv_size = avio_close_dyn_buf(dyn_cp, &codecpriv);
00511     if (codecpriv_size)
00512         put_ebml_binary(pb, MATROSKA_ID_CODECPRIVATE, codecpriv, codecpriv_size);
00513     av_free(codecpriv);
00514     return ret;
00515 }
00516 
00517 static int mkv_write_tracks(AVFormatContext *s)
00518 {
00519     MatroskaMuxContext *mkv = s->priv_data;
00520     AVIOContext *pb = s->pb;
00521     ebml_master tracks;
00522     int i, j, ret;
00523 
00524     ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_TRACKS, avio_tell(pb));
00525     if (ret < 0) return ret;
00526 
00527     tracks = start_ebml_master(pb, MATROSKA_ID_TRACKS, 0);
00528     for (i = 0; i < s->nb_streams; i++) {
00529         AVStream *st = s->streams[i];
00530         AVCodecContext *codec = st->codec;
00531         ebml_master subinfo, track;
00532         int native_id = 0;
00533         int qt_id = 0;
00534         int bit_depth = av_get_bits_per_sample(codec->codec_id);
00535         int sample_rate = codec->sample_rate;
00536         int output_sample_rate = 0;
00537         AVDictionaryEntry *tag;
00538 
00539         if (codec->codec_type == AVMEDIA_TYPE_ATTACHMENT) {
00540             mkv->have_attachments = 1;
00541             continue;
00542         }
00543 
00544         if (!bit_depth)
00545             bit_depth = av_get_bytes_per_sample(codec->sample_fmt) << 3;
00546 
00547         if (codec->codec_id == CODEC_ID_AAC)
00548             get_aac_sample_rates(s, codec, &sample_rate, &output_sample_rate);
00549 
00550         track = start_ebml_master(pb, MATROSKA_ID_TRACKENTRY, 0);
00551         put_ebml_uint (pb, MATROSKA_ID_TRACKNUMBER     , i + 1);
00552         put_ebml_uint (pb, MATROSKA_ID_TRACKUID        , i + 1);
00553         put_ebml_uint (pb, MATROSKA_ID_TRACKFLAGLACING , 0);    // no lacing (yet)
00554 
00555         if ((tag = av_dict_get(st->metadata, "title", NULL, 0)))
00556             put_ebml_string(pb, MATROSKA_ID_TRACKNAME, tag->value);
00557         tag = av_dict_get(st->metadata, "language", NULL, 0);
00558         put_ebml_string(pb, MATROSKA_ID_TRACKLANGUAGE, tag ? tag->value:"und");
00559 
00560         if (st->disposition)
00561             put_ebml_uint(pb, MATROSKA_ID_TRACKFLAGDEFAULT, !!(st->disposition & AV_DISPOSITION_DEFAULT));
00562 
00563         // look for a codec ID string specific to mkv to use,
00564         // if none are found, use AVI codes
00565         for (j = 0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++) {
00566             if (ff_mkv_codec_tags[j].id == codec->codec_id) {
00567                 put_ebml_string(pb, MATROSKA_ID_CODECID, ff_mkv_codec_tags[j].str);
00568                 native_id = 1;
00569                 break;
00570             }
00571         }
00572 
00573         if (mkv->mode == MODE_WEBM && !(codec->codec_id == CODEC_ID_VP8 ||
00574                                         codec->codec_id == CODEC_ID_VORBIS)) {
00575             av_log(s, AV_LOG_ERROR,
00576                    "Only VP8 video and Vorbis audio are supported for WebM.\n");
00577             return AVERROR(EINVAL);
00578         }
00579 
00580         switch (codec->codec_type) {
00581             case AVMEDIA_TYPE_VIDEO:
00582                 put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_VIDEO);
00583                 put_ebml_uint(pb, MATROSKA_ID_TRACKDEFAULTDURATION, av_q2d(codec->time_base)*1E9);
00584 
00585                 if (!native_id &&
00586                       ff_codec_get_tag(codec_movvideo_tags, codec->codec_id) &&
00587                     (!ff_codec_get_tag(ff_codec_bmp_tags,   codec->codec_id)
00588                      || codec->codec_id == CODEC_ID_SVQ1
00589                      || codec->codec_id == CODEC_ID_SVQ3
00590                      || codec->codec_id == CODEC_ID_CINEPAK))
00591                     qt_id = 1;
00592 
00593                 if (qt_id)
00594                     put_ebml_string(pb, MATROSKA_ID_CODECID, "V_QUICKTIME");
00595                 else if (!native_id) {
00596                     // if there is no mkv-specific codec ID, use VFW mode
00597                     put_ebml_string(pb, MATROSKA_ID_CODECID, "V_MS/VFW/FOURCC");
00598                     mkv->tracks[i].write_dts = 1;
00599                 }
00600 
00601                 subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKVIDEO, 0);
00602                 // XXX: interlace flag?
00603                 put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELWIDTH , codec->width);
00604                 put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELHEIGHT, codec->height);
00605                 if ((tag = av_dict_get(s->metadata, "stereo_mode", NULL, 0))) {
00606                     uint8_t stereo_fmt = atoi(tag->value);
00607                     int valid_fmt = 0;
00608 
00609                     switch (mkv->mode) {
00610                     case MODE_WEBM:
00611                         if (stereo_fmt <= MATROSKA_VIDEO_STEREOMODE_TYPE_TOP_BOTTOM
00612                             || stereo_fmt == MATROSKA_VIDEO_STEREOMODE_TYPE_RIGHT_LEFT)
00613                             valid_fmt = 1;
00614                         break;
00615                     case MODE_MATROSKAv2:
00616                         if (stereo_fmt <= MATROSKA_VIDEO_STEREOMODE_TYPE_BOTH_EYES_BLOCK_RL)
00617                             valid_fmt = 1;
00618                         break;
00619                     }
00620 
00621                     if (valid_fmt)
00622                         put_ebml_uint (pb, MATROSKA_ID_VIDEOSTEREOMODE, stereo_fmt);
00623                 }
00624                 if (st->sample_aspect_ratio.num) {
00625                     int d_width = codec->width*av_q2d(st->sample_aspect_ratio);
00626                     put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYWIDTH , d_width);
00627                     put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYHEIGHT, codec->height);
00628                     put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYUNIT, 3);
00629                 }
00630                 end_ebml_master(pb, subinfo);
00631                 break;
00632 
00633             case AVMEDIA_TYPE_AUDIO:
00634                 put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_AUDIO);
00635 
00636                 if (!native_id)
00637                     // no mkv-specific ID, use ACM mode
00638                     put_ebml_string(pb, MATROSKA_ID_CODECID, "A_MS/ACM");
00639 
00640                 subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKAUDIO, 0);
00641                 put_ebml_uint  (pb, MATROSKA_ID_AUDIOCHANNELS    , codec->channels);
00642                 put_ebml_float (pb, MATROSKA_ID_AUDIOSAMPLINGFREQ, sample_rate);
00643                 if (output_sample_rate)
00644                     put_ebml_float(pb, MATROSKA_ID_AUDIOOUTSAMPLINGFREQ, output_sample_rate);
00645                 if (bit_depth)
00646                     put_ebml_uint(pb, MATROSKA_ID_AUDIOBITDEPTH, bit_depth);
00647                 end_ebml_master(pb, subinfo);
00648                 break;
00649 
00650             case AVMEDIA_TYPE_SUBTITLE:
00651                 put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_SUBTITLE);
00652                 if (!native_id) {
00653                     av_log(s, AV_LOG_ERROR, "Subtitle codec %d is not supported.\n", codec->codec_id);
00654                     return AVERROR(ENOSYS);
00655                 }
00656                 break;
00657             default:
00658                 av_log(s, AV_LOG_ERROR, "Only audio, video, and subtitles are supported for Matroska.\n");
00659                 break;
00660         }
00661         ret = mkv_write_codecprivate(s, pb, codec, native_id, qt_id);
00662         if (ret < 0) return ret;
00663 
00664         end_ebml_master(pb, track);
00665 
00666         // ms precision is the de-facto standard timescale for mkv files
00667         avpriv_set_pts_info(st, 64, 1, 1000);
00668     }
00669     end_ebml_master(pb, tracks);
00670     return 0;
00671 }
00672 
00673 static int mkv_write_chapters(AVFormatContext *s)
00674 {
00675     MatroskaMuxContext *mkv = s->priv_data;
00676     AVIOContext *pb = s->pb;
00677     ebml_master chapters, editionentry;
00678     AVRational scale = {1, 1E9};
00679     int i, ret;
00680 
00681     if (!s->nb_chapters)
00682         return 0;
00683 
00684     ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CHAPTERS, avio_tell(pb));
00685     if (ret < 0) return ret;
00686 
00687     chapters     = start_ebml_master(pb, MATROSKA_ID_CHAPTERS    , 0);
00688     editionentry = start_ebml_master(pb, MATROSKA_ID_EDITIONENTRY, 0);
00689     put_ebml_uint(pb, MATROSKA_ID_EDITIONFLAGDEFAULT, 1);
00690     put_ebml_uint(pb, MATROSKA_ID_EDITIONFLAGHIDDEN , 0);
00691     for (i = 0; i < s->nb_chapters; i++) {
00692         ebml_master chapteratom, chapterdisplay;
00693         AVChapter *c     = s->chapters[i];
00694         AVDictionaryEntry *t = NULL;
00695 
00696         chapteratom = start_ebml_master(pb, MATROSKA_ID_CHAPTERATOM, 0);
00697         put_ebml_uint(pb, MATROSKA_ID_CHAPTERUID, c->id);
00698         put_ebml_uint(pb, MATROSKA_ID_CHAPTERTIMESTART,
00699                       av_rescale_q(c->start, c->time_base, scale));
00700         put_ebml_uint(pb, MATROSKA_ID_CHAPTERTIMEEND,
00701                       av_rescale_q(c->end,   c->time_base, scale));
00702         put_ebml_uint(pb, MATROSKA_ID_CHAPTERFLAGHIDDEN , 0);
00703         put_ebml_uint(pb, MATROSKA_ID_CHAPTERFLAGENABLED, 1);
00704         if ((t = av_dict_get(c->metadata, "title", NULL, 0))) {
00705             chapterdisplay = start_ebml_master(pb, MATROSKA_ID_CHAPTERDISPLAY, 0);
00706             put_ebml_string(pb, MATROSKA_ID_CHAPSTRING, t->value);
00707             put_ebml_string(pb, MATROSKA_ID_CHAPLANG  , "und");
00708             end_ebml_master(pb, chapterdisplay);
00709         }
00710         end_ebml_master(pb, chapteratom);
00711     }
00712     end_ebml_master(pb, editionentry);
00713     end_ebml_master(pb, chapters);
00714     return 0;
00715 }
00716 
00717 static void mkv_write_simpletag(AVIOContext *pb, AVDictionaryEntry *t)
00718 {
00719     uint8_t *key = av_strdup(t->key);
00720     uint8_t *p   = key;
00721     const uint8_t *lang = NULL;
00722     ebml_master tag;
00723 
00724     if ((p = strrchr(p, '-')) &&
00725         (lang = av_convert_lang_to(p + 1, AV_LANG_ISO639_2_BIBL)))
00726         *p = 0;
00727 
00728     p = key;
00729     while (*p) {
00730         if (*p == ' ')
00731             *p = '_';
00732         else if (*p >= 'a' && *p <= 'z')
00733             *p -= 'a' - 'A';
00734         p++;
00735     }
00736 
00737     tag = start_ebml_master(pb, MATROSKA_ID_SIMPLETAG, 0);
00738     put_ebml_string(pb, MATROSKA_ID_TAGNAME, key);
00739     if (lang)
00740         put_ebml_string(pb, MATROSKA_ID_TAGLANG, lang);
00741     put_ebml_string(pb, MATROSKA_ID_TAGSTRING, t->value);
00742     end_ebml_master(pb, tag);
00743 
00744     av_freep(&key);
00745 }
00746 
00747 static int mkv_write_tag(AVFormatContext *s, AVDictionary *m, unsigned int elementid,
00748                          unsigned int uid, ebml_master *tags)
00749 {
00750     MatroskaMuxContext *mkv = s->priv_data;
00751     ebml_master tag, targets;
00752     AVDictionaryEntry *t = NULL;
00753     int ret;
00754 
00755     if (!tags->pos) {
00756         ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_TAGS, avio_tell(s->pb));
00757         if (ret < 0) return ret;
00758 
00759         *tags = start_ebml_master(s->pb, MATROSKA_ID_TAGS, 0);
00760     }
00761 
00762     tag     = start_ebml_master(s->pb, MATROSKA_ID_TAG,        0);
00763     targets = start_ebml_master(s->pb, MATROSKA_ID_TAGTARGETS, 0);
00764     if (elementid)
00765         put_ebml_uint(s->pb, elementid, uid);
00766     end_ebml_master(s->pb, targets);
00767 
00768     while ((t = av_dict_get(m, "", t, AV_DICT_IGNORE_SUFFIX)))
00769         if (av_strcasecmp(t->key, "title"))
00770             mkv_write_simpletag(s->pb, t);
00771 
00772     end_ebml_master(s->pb, tag);
00773     return 0;
00774 }
00775 
00776 static int mkv_write_tags(AVFormatContext *s)
00777 {
00778     ebml_master tags = {0};
00779     int i, ret;
00780 
00781     ff_metadata_conv_ctx(s, ff_mkv_metadata_conv, NULL);
00782 
00783     if (av_dict_get(s->metadata, "", NULL, AV_DICT_IGNORE_SUFFIX)) {
00784         ret = mkv_write_tag(s, s->metadata, 0, 0, &tags);
00785         if (ret < 0) return ret;
00786     }
00787 
00788     for (i = 0; i < s->nb_streams; i++) {
00789         AVStream *st = s->streams[i];
00790 
00791         if (!av_dict_get(st->metadata, "", 0, AV_DICT_IGNORE_SUFFIX))
00792             continue;
00793 
00794         ret = mkv_write_tag(s, st->metadata, MATROSKA_ID_TAGTARGETS_TRACKUID, i + 1, &tags);
00795         if (ret < 0) return ret;
00796     }
00797 
00798     for (i = 0; i < s->nb_chapters; i++) {
00799         AVChapter *ch = s->chapters[i];
00800 
00801         if (!av_dict_get(ch->metadata, "", NULL, AV_DICT_IGNORE_SUFFIX))
00802             continue;
00803 
00804         ret = mkv_write_tag(s, ch->metadata, MATROSKA_ID_TAGTARGETS_CHAPTERUID, ch->id, &tags);
00805         if (ret < 0) return ret;
00806     }
00807 
00808     if (tags.pos)
00809         end_ebml_master(s->pb, tags);
00810     return 0;
00811 }
00812 
00813 static int mkv_write_attachments(AVFormatContext *s)
00814 {
00815     MatroskaMuxContext *mkv = s->priv_data;
00816     AVIOContext *pb = s->pb;
00817     ebml_master attachments;
00818     AVLFG c;
00819     int i, ret;
00820 
00821     if (!mkv->have_attachments)
00822         return 0;
00823 
00824     av_lfg_init(&c, av_get_random_seed());
00825 
00826     ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_ATTACHMENTS, avio_tell(pb));
00827     if (ret < 0) return ret;
00828 
00829     attachments = start_ebml_master(pb, MATROSKA_ID_ATTACHMENTS, 0);
00830 
00831     for (i = 0; i < s->nb_streams; i++) {
00832         AVStream *st = s->streams[i];
00833         ebml_master attached_file;
00834         AVDictionaryEntry *t;
00835         const char *mimetype = NULL;
00836 
00837         if (st->codec->codec_type != AVMEDIA_TYPE_ATTACHMENT)
00838             continue;
00839 
00840         attached_file = start_ebml_master(pb, MATROSKA_ID_ATTACHEDFILE, 0);
00841 
00842         if (t = av_dict_get(st->metadata, "title", NULL, 0))
00843             put_ebml_string(pb, MATROSKA_ID_FILEDESC, t->value);
00844         if (!(t = av_dict_get(st->metadata, "filename", NULL, 0))) {
00845             av_log(s, AV_LOG_ERROR, "Attachment stream %d has no filename tag.\n", i);
00846             return AVERROR(EINVAL);
00847         }
00848         put_ebml_string(pb, MATROSKA_ID_FILENAME, t->value);
00849         if (t = av_dict_get(st->metadata, "mimetype", NULL, 0))
00850             mimetype = t->value;
00851         else if (st->codec->codec_id != CODEC_ID_NONE ) {
00852             int i;
00853             for (i = 0; ff_mkv_mime_tags[i].id != CODEC_ID_NONE; i++)
00854                 if (ff_mkv_mime_tags[i].id == st->codec->codec_id) {
00855                     mimetype = ff_mkv_mime_tags[i].str;
00856                     break;
00857                 }
00858         }
00859         if (!mimetype) {
00860             av_log(s, AV_LOG_ERROR, "Attachment stream %d has no mimetype tag and "
00861                                     "it cannot be deduced from the codec id.\n", i);
00862             return AVERROR(EINVAL);
00863         }
00864 
00865         put_ebml_string(pb, MATROSKA_ID_FILEMIMETYPE, mimetype);
00866         put_ebml_binary(pb, MATROSKA_ID_FILEDATA, st->codec->extradata, st->codec->extradata_size);
00867         put_ebml_uint(pb, MATROSKA_ID_FILEUID, av_lfg_get(&c));
00868         end_ebml_master(pb, attached_file);
00869     }
00870     end_ebml_master(pb, attachments);
00871 
00872     return 0;
00873 }
00874 
00875 static int mkv_write_header(AVFormatContext *s)
00876 {
00877     MatroskaMuxContext *mkv = s->priv_data;
00878     AVIOContext *pb = s->pb;
00879     ebml_master ebml_header, segment_info;
00880     AVDictionaryEntry *tag;
00881     int ret, i;
00882 
00883     if (!strcmp(s->oformat->name, "webm")) mkv->mode = MODE_WEBM;
00884     else                                   mkv->mode = MODE_MATROSKAv2;
00885 
00886     mkv->tracks = av_mallocz(s->nb_streams * sizeof(*mkv->tracks));
00887     if (!mkv->tracks)
00888         return AVERROR(ENOMEM);
00889 
00890     ebml_header = start_ebml_master(pb, EBML_ID_HEADER, 0);
00891     put_ebml_uint   (pb, EBML_ID_EBMLVERSION        ,           1);
00892     put_ebml_uint   (pb, EBML_ID_EBMLREADVERSION    ,           1);
00893     put_ebml_uint   (pb, EBML_ID_EBMLMAXIDLENGTH    ,           4);
00894     put_ebml_uint   (pb, EBML_ID_EBMLMAXSIZELENGTH  ,           8);
00895     put_ebml_string (pb, EBML_ID_DOCTYPE            , s->oformat->name);
00896     put_ebml_uint   (pb, EBML_ID_DOCTYPEVERSION     ,           2);
00897     put_ebml_uint   (pb, EBML_ID_DOCTYPEREADVERSION ,           2);
00898     end_ebml_master(pb, ebml_header);
00899 
00900     mkv->segment = start_ebml_master(pb, MATROSKA_ID_SEGMENT, 0);
00901     mkv->segment_offset = avio_tell(pb);
00902 
00903     // we write 2 seek heads - one at the end of the file to point to each
00904     // cluster, and one at the beginning to point to all other level one
00905     // elements (including the seek head at the end of the file), which
00906     // isn't more than 10 elements if we only write one of each other
00907     // currently defined level 1 element
00908     mkv->main_seekhead    = mkv_start_seekhead(pb, mkv->segment_offset, 10);
00909     if (!mkv->main_seekhead)
00910         return AVERROR(ENOMEM);
00911 
00912     ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_INFO, avio_tell(pb));
00913     if (ret < 0) return ret;
00914 
00915     segment_info = start_ebml_master(pb, MATROSKA_ID_INFO, 0);
00916     put_ebml_uint(pb, MATROSKA_ID_TIMECODESCALE, 1000000);
00917     if ((tag = av_dict_get(s->metadata, "title", NULL, 0)))
00918         put_ebml_string(pb, MATROSKA_ID_TITLE, tag->value);
00919     if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) {
00920         uint32_t segment_uid[4];
00921         AVLFG lfg;
00922 
00923         av_lfg_init(&lfg, av_get_random_seed());
00924 
00925         for (i = 0; i < 4; i++)
00926             segment_uid[i] = av_lfg_get(&lfg);
00927 
00928         put_ebml_string(pb, MATROSKA_ID_MUXINGAPP , LIBAVFORMAT_IDENT);
00929         put_ebml_string(pb, MATROSKA_ID_WRITINGAPP, LIBAVFORMAT_IDENT);
00930         put_ebml_binary(pb, MATROSKA_ID_SEGMENTUID, segment_uid, 16);
00931     }
00932 
00933     // reserve space for the duration
00934     mkv->duration = 0;
00935     mkv->duration_offset = avio_tell(pb);
00936     put_ebml_void(pb, 11);                  // assumes double-precision float to be written
00937     end_ebml_master(pb, segment_info);
00938 
00939     ret = mkv_write_tracks(s);
00940     if (ret < 0) return ret;
00941 
00942     if (mkv->mode != MODE_WEBM) {
00943         ret = mkv_write_chapters(s);
00944         if (ret < 0) return ret;
00945 
00946         ret = mkv_write_tags(s);
00947         if (ret < 0) return ret;
00948 
00949         ret = mkv_write_attachments(s);
00950         if (ret < 0) return ret;
00951     }
00952 
00953     if (!s->pb->seekable)
00954         mkv_write_seekhead(pb, mkv->main_seekhead);
00955 
00956     mkv->cues = mkv_start_cues(mkv->segment_offset);
00957     if (mkv->cues == NULL)
00958         return AVERROR(ENOMEM);
00959 
00960     av_init_packet(&mkv->cur_audio_pkt);
00961     mkv->cur_audio_pkt.size = 0;
00962     mkv->audio_buffer_size  = 0;
00963 
00964     avio_flush(pb);
00965     return 0;
00966 }
00967 
00968 static int mkv_blockgroup_size(int pkt_size)
00969 {
00970     int size = pkt_size + 4;
00971     size += ebml_num_size(size);
00972     size += 2;              // EBML ID for block and block duration
00973     size += 8;              // max size of block duration
00974     size += ebml_num_size(size);
00975     size += 1;              // blockgroup EBML ID
00976     return size;
00977 }
00978 
00979 static int ass_get_duration(const uint8_t *p)
00980 {
00981     int sh, sm, ss, sc, eh, em, es, ec;
00982     uint64_t start, end;
00983 
00984     if (sscanf(p, "%*[^,],%d:%d:%d%*c%d,%d:%d:%d%*c%d",
00985                &sh, &sm, &ss, &sc, &eh, &em, &es, &ec) != 8)
00986         return 0;
00987     start = 3600000*sh + 60000*sm + 1000*ss + 10*sc;
00988     end   = 3600000*eh + 60000*em + 1000*es + 10*ec;
00989     return end - start;
00990 }
00991 
00992 static int mkv_write_ass_blocks(AVFormatContext *s, AVIOContext *pb, AVPacket *pkt)
00993 {
00994     MatroskaMuxContext *mkv = s->priv_data;
00995     int i, layer = 0, max_duration = 0, size, line_size, data_size = pkt->size;
00996     uint8_t *start, *end, *data = pkt->data;
00997     ebml_master blockgroup;
00998     char buffer[2048];
00999 
01000     while (data_size) {
01001         int duration = ass_get_duration(data);
01002         max_duration = FFMAX(duration, max_duration);
01003         end = memchr(data, '\n', data_size);
01004         size = line_size = end ? end-data+1 : data_size;
01005         size -= end ? (end[-1]=='\r')+1 : 0;
01006         start = data;
01007         for (i=0; i<3; i++, start++)
01008             if (!(start = memchr(start, ',', size-(start-data))))
01009                 return max_duration;
01010         size -= start - data;
01011         sscanf(data, "Dialogue: %d,", &layer);
01012         i = snprintf(buffer, sizeof(buffer), "%"PRId64",%d,",
01013                      s->streams[pkt->stream_index]->nb_frames, layer);
01014         size = FFMIN(i+size, sizeof(buffer));
01015         memcpy(buffer+i, start, size-i);
01016 
01017         av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, "
01018                "pts %" PRId64 ", duration %d\n",
01019                avio_tell(pb), size, pkt->pts, duration);
01020         blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(size));
01021         put_ebml_id(pb, MATROSKA_ID_BLOCK);
01022         put_ebml_num(pb, size+4, 0);
01023         avio_w8(pb, 0x80 | (pkt->stream_index + 1));     // this assumes stream_index is less than 126
01024         avio_wb16(pb, pkt->pts - mkv->cluster_pts);
01025         avio_w8(pb, 0);
01026         avio_write(pb, buffer, size);
01027         put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
01028         end_ebml_master(pb, blockgroup);
01029 
01030         data += line_size;
01031         data_size -= line_size;
01032     }
01033 
01034     return max_duration;
01035 }
01036 
01037 static void mkv_write_block(AVFormatContext *s, AVIOContext *pb,
01038                             unsigned int blockid, AVPacket *pkt, int flags)
01039 {
01040     MatroskaMuxContext *mkv = s->priv_data;
01041     AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
01042     uint8_t *data = NULL;
01043     int size = pkt->size;
01044     int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts;
01045 
01046     av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, "
01047            "pts %" PRId64 ", dts %" PRId64 ", duration %d, flags %d\n",
01048            avio_tell(pb), pkt->size, pkt->pts, pkt->dts, pkt->duration, flags);
01049     if (codec->codec_id == CODEC_ID_H264 && codec->extradata_size > 0 &&
01050         (AV_RB24(codec->extradata) == 1 || AV_RB32(codec->extradata) == 1))
01051         ff_avc_parse_nal_units_buf(pkt->data, &data, &size);
01052     else
01053         data = pkt->data;
01054     put_ebml_id(pb, blockid);
01055     put_ebml_num(pb, size+4, 0);
01056     avio_w8(pb, 0x80 | (pkt->stream_index + 1));     // this assumes stream_index is less than 126
01057     avio_wb16(pb, ts - mkv->cluster_pts);
01058     avio_w8(pb, flags);
01059     avio_write(pb, data, size);
01060     if (data != pkt->data)
01061         av_free(data);
01062 }
01063 
01064 static int srt_get_duration(uint8_t **buf)
01065 {
01066     int i, duration = 0;
01067 
01068     for (i=0; i<2 && !duration; i++) {
01069         int s_hour, s_min, s_sec, s_hsec, e_hour, e_min, e_sec, e_hsec;
01070         if (sscanf(*buf, "%d:%2d:%2d%*1[,.]%3d --> %d:%2d:%2d%*1[,.]%3d",
01071                    &s_hour, &s_min, &s_sec, &s_hsec,
01072                    &e_hour, &e_min, &e_sec, &e_hsec) == 8) {
01073             s_min  +=   60*s_hour;      e_min  +=   60*e_hour;
01074             s_sec  +=   60*s_min;       e_sec  +=   60*e_min;
01075             s_hsec += 1000*s_sec;       e_hsec += 1000*e_sec;
01076             duration = e_hsec - s_hsec;
01077         }
01078         *buf += strcspn(*buf, "\n") + 1;
01079     }
01080     return duration;
01081 }
01082 
01083 static int mkv_write_srt_blocks(AVFormatContext *s, AVIOContext *pb, AVPacket *pkt)
01084 {
01085     ebml_master blockgroup;
01086     AVPacket pkt2 = *pkt;
01087     int64_t duration = srt_get_duration(&pkt2.data);
01088     pkt2.size -= pkt2.data - pkt->data;
01089 
01090     blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP,
01091                                    mkv_blockgroup_size(pkt2.size));
01092     mkv_write_block(s, pb, MATROSKA_ID_BLOCK, &pkt2, 0);
01093     put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
01094     end_ebml_master(pb, blockgroup);
01095 
01096     return duration;
01097 }
01098 
01099 static void mkv_flush_dynbuf(AVFormatContext *s)
01100 {
01101     MatroskaMuxContext *mkv = s->priv_data;
01102     int bufsize;
01103     uint8_t *dyn_buf;
01104 
01105     if (!mkv->dyn_bc)
01106         return;
01107 
01108     bufsize = avio_close_dyn_buf(mkv->dyn_bc, &dyn_buf);
01109     avio_write(s->pb, dyn_buf, bufsize);
01110     av_free(dyn_buf);
01111     mkv->dyn_bc = NULL;
01112 }
01113 
01114 static int mkv_write_packet_internal(AVFormatContext *s, AVPacket *pkt)
01115 {
01116     MatroskaMuxContext *mkv = s->priv_data;
01117     AVIOContext *pb = s->pb;
01118     AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
01119     int keyframe = !!(pkt->flags & AV_PKT_FLAG_KEY);
01120     int duration = pkt->duration;
01121     int ret;
01122     int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts;
01123 
01124     if (ts == AV_NOPTS_VALUE) {
01125         av_log(s, AV_LOG_ERROR, "Can't write packet with unknown timestamp\n");
01126         return AVERROR(EINVAL);
01127     }
01128 
01129     if (!s->pb->seekable) {
01130         if (!mkv->dyn_bc)
01131             avio_open_dyn_buf(&mkv->dyn_bc);
01132         pb = mkv->dyn_bc;
01133     }
01134 
01135     if (!mkv->cluster_pos) {
01136         mkv->cluster_pos = avio_tell(s->pb);
01137         mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER, 0);
01138         put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, FFMAX(0, ts));
01139         mkv->cluster_pts = FFMAX(0, ts);
01140     }
01141 
01142     if (codec->codec_type != AVMEDIA_TYPE_SUBTITLE) {
01143         mkv_write_block(s, pb, MATROSKA_ID_SIMPLEBLOCK, pkt, keyframe << 7);
01144     } else if (codec->codec_id == CODEC_ID_SSA) {
01145         duration = mkv_write_ass_blocks(s, pb, pkt);
01146     } else if (codec->codec_id == CODEC_ID_SRT) {
01147         duration = mkv_write_srt_blocks(s, pb, pkt);
01148     } else {
01149         ebml_master blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(pkt->size));
01150         duration = pkt->convergence_duration;
01151         mkv_write_block(s, pb, MATROSKA_ID_BLOCK, pkt, 0);
01152         put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
01153         end_ebml_master(pb, blockgroup);
01154     }
01155 
01156     if (codec->codec_type == AVMEDIA_TYPE_VIDEO && keyframe) {
01157         ret = mkv_add_cuepoint(mkv->cues, pkt->stream_index, ts, mkv->cluster_pos);
01158         if (ret < 0) return ret;
01159     }
01160 
01161     mkv->duration = FFMAX(mkv->duration, ts + duration);
01162     return 0;
01163 }
01164 
01165 static int mkv_copy_packet(MatroskaMuxContext *mkv, const AVPacket *pkt)
01166 {
01167     uint8_t *data           = mkv->cur_audio_pkt.data;
01168     mkv->cur_audio_pkt      = *pkt;
01169     mkv->cur_audio_pkt.data = av_fast_realloc(data, &mkv->audio_buffer_size, pkt->size);
01170     if (!mkv->cur_audio_pkt.data)
01171         return AVERROR(ENOMEM);
01172 
01173     memcpy(mkv->cur_audio_pkt.data, pkt->data, pkt->size);
01174     mkv->cur_audio_pkt.size = pkt->size;
01175     return 0;
01176 }
01177 
01178 static int mkv_write_packet(AVFormatContext *s, AVPacket *pkt)
01179 {
01180     MatroskaMuxContext *mkv = s->priv_data;
01181     AVIOContext *pb = s->pb->seekable ? s->pb : mkv->dyn_bc;
01182     AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
01183     int ret, keyframe = !!(pkt->flags & AV_PKT_FLAG_KEY);
01184     int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts;
01185     int cluster_size = avio_tell(pb) - (s->pb->seekable ? mkv->cluster_pos : 0);
01186 
01187     // start a new cluster every 5 MB or 5 sec, or 32k / 1 sec for streaming or
01188     // after 4k and on a keyframe
01189     if (mkv->cluster_pos &&
01190         ((!s->pb->seekable && (cluster_size > 32*1024 || ts > mkv->cluster_pts + 1000))
01191          ||                      cluster_size > 5*1024*1024 || ts > mkv->cluster_pts + 5000
01192          || (codec->codec_type == AVMEDIA_TYPE_VIDEO && keyframe && cluster_size > 4*1024))) {
01193         av_log(s, AV_LOG_DEBUG, "Starting new cluster at offset %" PRIu64
01194                " bytes, pts %" PRIu64 "\n", avio_tell(pb), ts);
01195         end_ebml_master(pb, mkv->cluster);
01196         mkv->cluster_pos = 0;
01197         if (mkv->dyn_bc)
01198             mkv_flush_dynbuf(s);
01199     }
01200 
01201     // check if we have an audio packet cached
01202     if (mkv->cur_audio_pkt.size > 0) {
01203         ret = mkv_write_packet_internal(s, &mkv->cur_audio_pkt);
01204         mkv->cur_audio_pkt.size = 0;
01205         if (ret < 0) {
01206             av_log(s, AV_LOG_ERROR, "Could not write cached audio packet ret:%d\n", ret);
01207             return ret;
01208         }
01209     }
01210 
01211     // buffer an audio packet to ensure the packet containing the video
01212     // keyframe's timecode is contained in the same cluster for WebM
01213     if (codec->codec_type == AVMEDIA_TYPE_AUDIO)
01214         ret = mkv_copy_packet(mkv, pkt);
01215     else
01216         ret = mkv_write_packet_internal(s, pkt);
01217     return ret;
01218 }
01219 
01220 static int mkv_write_trailer(AVFormatContext *s)
01221 {
01222     MatroskaMuxContext *mkv = s->priv_data;
01223     AVIOContext *pb = s->pb;
01224     int64_t currentpos, cuespos;
01225     int ret;
01226 
01227     // check if we have an audio packet cached
01228     if (mkv->cur_audio_pkt.size > 0) {
01229         ret = mkv_write_packet_internal(s, &mkv->cur_audio_pkt);
01230         mkv->cur_audio_pkt.size = 0;
01231         if (ret < 0) {
01232             av_log(s, AV_LOG_ERROR, "Could not write cached audio packet ret:%d\n", ret);
01233             return ret;
01234         }
01235     }
01236 
01237     if (mkv->dyn_bc) {
01238         end_ebml_master(mkv->dyn_bc, mkv->cluster);
01239         mkv_flush_dynbuf(s);
01240     } else if (mkv->cluster_pos) {
01241         end_ebml_master(pb, mkv->cluster);
01242     }
01243 
01244     if (pb->seekable) {
01245         if (mkv->cues->num_entries) {
01246             cuespos = mkv_write_cues(pb, mkv->cues, s->nb_streams);
01247 
01248             ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CUES, cuespos);
01249             if (ret < 0) return ret;
01250         }
01251 
01252         mkv_write_seekhead(pb, mkv->main_seekhead);
01253 
01254         // update the duration
01255         av_log(s, AV_LOG_DEBUG, "end duration = %" PRIu64 "\n", mkv->duration);
01256         currentpos = avio_tell(pb);
01257         avio_seek(pb, mkv->duration_offset, SEEK_SET);
01258         put_ebml_float(pb, MATROSKA_ID_DURATION, mkv->duration);
01259 
01260         avio_seek(pb, currentpos, SEEK_SET);
01261     }
01262 
01263     end_ebml_master(pb, mkv->segment);
01264     av_free(mkv->tracks);
01265     av_freep(&mkv->cues->entries);
01266     av_freep(&mkv->cues);
01267     av_destruct_packet(&mkv->cur_audio_pkt);
01268     avio_flush(pb);
01269     return 0;
01270 }
01271 
01272 static int mkv_query_codec(enum CodecID codec_id, int std_compliance)
01273 {
01274     int i;
01275     for (i = 0; ff_mkv_codec_tags[i].id != CODEC_ID_NONE; i++)
01276         if (ff_mkv_codec_tags[i].id == codec_id)
01277             return 1;
01278 
01279     if (std_compliance < FF_COMPLIANCE_NORMAL) {                // mkv theoretically supports any
01280         enum AVMediaType type = avcodec_get_type(codec_id);     // video/audio through VFW/ACM
01281         if (type == AVMEDIA_TYPE_VIDEO || type == AVMEDIA_TYPE_AUDIO)
01282             return 1;
01283     }
01284 
01285     return 0;
01286 }
01287 
01288 #if CONFIG_MATROSKA_MUXER
01289 AVOutputFormat ff_matroska_muxer = {
01290     .name              = "matroska",
01291     .long_name         = NULL_IF_CONFIG_SMALL("Matroska file format"),
01292     .mime_type         = "video/x-matroska",
01293     .extensions        = "mkv",
01294     .priv_data_size    = sizeof(MatroskaMuxContext),
01295 #if CONFIG_LIBVORBIS_ENCODER
01296     .audio_codec       = CODEC_ID_VORBIS,
01297 #else
01298     .audio_codec       = CODEC_ID_AC3,
01299 #endif
01300 #if CONFIG_LIBX264_ENCODER
01301     .video_codec       = CODEC_ID_H264,
01302 #else
01303     .video_codec       = CODEC_ID_MPEG4,
01304 #endif
01305     .write_header      = mkv_write_header,
01306     .write_packet      = mkv_write_packet,
01307     .write_trailer     = mkv_write_trailer,
01308     .flags             = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS,
01309     .codec_tag         = (const AVCodecTag* const []){ff_codec_bmp_tags, ff_codec_wav_tags, 0},
01310     .subtitle_codec    = CODEC_ID_SSA,
01311     .query_codec       = mkv_query_codec,
01312 };
01313 #endif
01314 
01315 #if CONFIG_WEBM_MUXER
01316 AVOutputFormat ff_webm_muxer = {
01317     .name              = "webm",
01318     .long_name         = NULL_IF_CONFIG_SMALL("WebM file format"),
01319     .mime_type         = "video/webm",
01320     .extensions        = "webm",
01321     .priv_data_size    = sizeof(MatroskaMuxContext),
01322     .audio_codec       = CODEC_ID_VORBIS,
01323     .video_codec       = CODEC_ID_VP8,
01324     .write_header      = mkv_write_header,
01325     .write_packet      = mkv_write_packet,
01326     .write_trailer     = mkv_write_trailer,
01327     .flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS,
01328 };
01329 #endif
01330 
01331 #if CONFIG_MATROSKA_AUDIO_MUXER
01332 AVOutputFormat ff_matroska_audio_muxer = {
01333     .name              = "matroska",
01334     .long_name         = NULL_IF_CONFIG_SMALL("Matroska file format"),
01335     .mime_type         = "audio/x-matroska",
01336     .extensions        = "mka",
01337     .priv_data_size    = sizeof(MatroskaMuxContext),
01338 #if CONFIG_LIBVORBIS_ENCODER
01339     .audio_codec       = CODEC_ID_VORBIS,
01340 #else
01341     .audio_codec       = CODEC_ID_AC3,
01342 #endif
01343     .video_codec       = CODEC_ID_NONE,
01344     .write_header      = mkv_write_header,
01345     .write_packet      = mkv_write_packet,
01346     .write_trailer     = mkv_write_trailer,
01347     .flags = AVFMT_GLOBALHEADER,
01348     .codec_tag = (const AVCodecTag* const []){ff_codec_wav_tags, 0},
01349 };
01350 #endif
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