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             av_strcasecmp(t->key, "encoding_tool"))
00771             mkv_write_simpletag(s->pb, t);
00772 
00773     end_ebml_master(s->pb, tag);
00774     return 0;
00775 }
00776 
00777 static int mkv_write_tags(AVFormatContext *s)
00778 {
00779     ebml_master tags = {0};
00780     int i, ret;
00781 
00782     ff_metadata_conv_ctx(s, ff_mkv_metadata_conv, NULL);
00783 
00784     if (av_dict_get(s->metadata, "", NULL, AV_DICT_IGNORE_SUFFIX)) {
00785         ret = mkv_write_tag(s, s->metadata, 0, 0, &tags);
00786         if (ret < 0) return ret;
00787     }
00788 
00789     for (i = 0; i < s->nb_streams; i++) {
00790         AVStream *st = s->streams[i];
00791 
00792         if (!av_dict_get(st->metadata, "", 0, AV_DICT_IGNORE_SUFFIX))
00793             continue;
00794 
00795         ret = mkv_write_tag(s, st->metadata, MATROSKA_ID_TAGTARGETS_TRACKUID, i + 1, &tags);
00796         if (ret < 0) return ret;
00797     }
00798 
00799     for (i = 0; i < s->nb_chapters; i++) {
00800         AVChapter *ch = s->chapters[i];
00801 
00802         if (!av_dict_get(ch->metadata, "", NULL, AV_DICT_IGNORE_SUFFIX))
00803             continue;
00804 
00805         ret = mkv_write_tag(s, ch->metadata, MATROSKA_ID_TAGTARGETS_CHAPTERUID, ch->id, &tags);
00806         if (ret < 0) return ret;
00807     }
00808 
00809     if (tags.pos)
00810         end_ebml_master(s->pb, tags);
00811     return 0;
00812 }
00813 
00814 static int mkv_write_attachments(AVFormatContext *s)
00815 {
00816     MatroskaMuxContext *mkv = s->priv_data;
00817     AVIOContext *pb = s->pb;
00818     ebml_master attachments;
00819     AVLFG c;
00820     int i, ret;
00821 
00822     if (!mkv->have_attachments)
00823         return 0;
00824 
00825     av_lfg_init(&c, av_get_random_seed());
00826 
00827     ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_ATTACHMENTS, avio_tell(pb));
00828     if (ret < 0) return ret;
00829 
00830     attachments = start_ebml_master(pb, MATROSKA_ID_ATTACHMENTS, 0);
00831 
00832     for (i = 0; i < s->nb_streams; i++) {
00833         AVStream *st = s->streams[i];
00834         ebml_master attached_file;
00835         AVDictionaryEntry *t;
00836         const char *mimetype = NULL;
00837 
00838         if (st->codec->codec_type != AVMEDIA_TYPE_ATTACHMENT)
00839             continue;
00840 
00841         attached_file = start_ebml_master(pb, MATROSKA_ID_ATTACHEDFILE, 0);
00842 
00843         if (t = av_dict_get(st->metadata, "title", NULL, 0))
00844             put_ebml_string(pb, MATROSKA_ID_FILEDESC, t->value);
00845         if (!(t = av_dict_get(st->metadata, "filename", NULL, 0))) {
00846             av_log(s, AV_LOG_ERROR, "Attachment stream %d has no filename tag.\n", i);
00847             return AVERROR(EINVAL);
00848         }
00849         put_ebml_string(pb, MATROSKA_ID_FILENAME, t->value);
00850         if (t = av_dict_get(st->metadata, "mimetype", NULL, 0))
00851             mimetype = t->value;
00852         else if (st->codec->codec_id != CODEC_ID_NONE ) {
00853             int i;
00854             for (i = 0; ff_mkv_mime_tags[i].id != CODEC_ID_NONE; i++)
00855                 if (ff_mkv_mime_tags[i].id == st->codec->codec_id) {
00856                     mimetype = ff_mkv_mime_tags[i].str;
00857                     break;
00858                 }
00859         }
00860         if (!mimetype) {
00861             av_log(s, AV_LOG_ERROR, "Attachment stream %d has no mimetype tag and "
00862                                     "it cannot be deduced from the codec id.\n", i);
00863             return AVERROR(EINVAL);
00864         }
00865 
00866         put_ebml_string(pb, MATROSKA_ID_FILEMIMETYPE, mimetype);
00867         put_ebml_binary(pb, MATROSKA_ID_FILEDATA, st->codec->extradata, st->codec->extradata_size);
00868         put_ebml_uint(pb, MATROSKA_ID_FILEUID, av_lfg_get(&c));
00869         end_ebml_master(pb, attached_file);
00870     }
00871     end_ebml_master(pb, attachments);
00872 
00873     return 0;
00874 }
00875 
00876 static int mkv_write_header(AVFormatContext *s)
00877 {
00878     MatroskaMuxContext *mkv = s->priv_data;
00879     AVIOContext *pb = s->pb;
00880     ebml_master ebml_header, segment_info;
00881     AVDictionaryEntry *tag;
00882     int ret, i;
00883 
00884     if (!strcmp(s->oformat->name, "webm")) mkv->mode = MODE_WEBM;
00885     else                                   mkv->mode = MODE_MATROSKAv2;
00886 
00887     mkv->tracks = av_mallocz(s->nb_streams * sizeof(*mkv->tracks));
00888     if (!mkv->tracks)
00889         return AVERROR(ENOMEM);
00890 
00891     ebml_header = start_ebml_master(pb, EBML_ID_HEADER, 0);
00892     put_ebml_uint   (pb, EBML_ID_EBMLVERSION        ,           1);
00893     put_ebml_uint   (pb, EBML_ID_EBMLREADVERSION    ,           1);
00894     put_ebml_uint   (pb, EBML_ID_EBMLMAXIDLENGTH    ,           4);
00895     put_ebml_uint   (pb, EBML_ID_EBMLMAXSIZELENGTH  ,           8);
00896     put_ebml_string (pb, EBML_ID_DOCTYPE            , s->oformat->name);
00897     put_ebml_uint   (pb, EBML_ID_DOCTYPEVERSION     ,           2);
00898     put_ebml_uint   (pb, EBML_ID_DOCTYPEREADVERSION ,           2);
00899     end_ebml_master(pb, ebml_header);
00900 
00901     mkv->segment = start_ebml_master(pb, MATROSKA_ID_SEGMENT, 0);
00902     mkv->segment_offset = avio_tell(pb);
00903 
00904     // we write 2 seek heads - one at the end of the file to point to each
00905     // cluster, and one at the beginning to point to all other level one
00906     // elements (including the seek head at the end of the file), which
00907     // isn't more than 10 elements if we only write one of each other
00908     // currently defined level 1 element
00909     mkv->main_seekhead    = mkv_start_seekhead(pb, mkv->segment_offset, 10);
00910     if (!mkv->main_seekhead)
00911         return AVERROR(ENOMEM);
00912 
00913     ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_INFO, avio_tell(pb));
00914     if (ret < 0) return ret;
00915 
00916     segment_info = start_ebml_master(pb, MATROSKA_ID_INFO, 0);
00917     put_ebml_uint(pb, MATROSKA_ID_TIMECODESCALE, 1000000);
00918     if ((tag = av_dict_get(s->metadata, "title", NULL, 0)))
00919         put_ebml_string(pb, MATROSKA_ID_TITLE, tag->value);
00920     if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) {
00921         uint32_t segment_uid[4];
00922         AVLFG lfg;
00923 
00924         av_lfg_init(&lfg, av_get_random_seed());
00925 
00926         for (i = 0; i < 4; i++)
00927             segment_uid[i] = av_lfg_get(&lfg);
00928 
00929         put_ebml_string(pb, MATROSKA_ID_MUXINGAPP , LIBAVFORMAT_IDENT);
00930         if ((tag = av_dict_get(s->metadata, "encoding_tool", NULL, 0)))
00931             put_ebml_string(pb, MATROSKA_ID_WRITINGAPP, tag->value);
00932         else
00933             put_ebml_string(pb, MATROSKA_ID_WRITINGAPP, LIBAVFORMAT_IDENT);
00934         put_ebml_binary(pb, MATROSKA_ID_SEGMENTUID, segment_uid, 16);
00935     }
00936 
00937     // reserve space for the duration
00938     mkv->duration = 0;
00939     mkv->duration_offset = avio_tell(pb);
00940     put_ebml_void(pb, 11);                  // assumes double-precision float to be written
00941     end_ebml_master(pb, segment_info);
00942 
00943     ret = mkv_write_tracks(s);
00944     if (ret < 0) return ret;
00945 
00946     if (mkv->mode != MODE_WEBM) {
00947         ret = mkv_write_chapters(s);
00948         if (ret < 0) return ret;
00949 
00950         ret = mkv_write_tags(s);
00951         if (ret < 0) return ret;
00952 
00953         ret = mkv_write_attachments(s);
00954         if (ret < 0) return ret;
00955     }
00956 
00957     if (!s->pb->seekable)
00958         mkv_write_seekhead(pb, mkv->main_seekhead);
00959 
00960     mkv->cues = mkv_start_cues(mkv->segment_offset);
00961     if (mkv->cues == NULL)
00962         return AVERROR(ENOMEM);
00963 
00964     av_init_packet(&mkv->cur_audio_pkt);
00965     mkv->cur_audio_pkt.size = 0;
00966     mkv->audio_buffer_size  = 0;
00967 
00968     avio_flush(pb);
00969     return 0;
00970 }
00971 
00972 static int mkv_blockgroup_size(int pkt_size)
00973 {
00974     int size = pkt_size + 4;
00975     size += ebml_num_size(size);
00976     size += 2;              // EBML ID for block and block duration
00977     size += 8;              // max size of block duration
00978     size += ebml_num_size(size);
00979     size += 1;              // blockgroup EBML ID
00980     return size;
00981 }
00982 
00983 static int ass_get_duration(const uint8_t *p)
00984 {
00985     int sh, sm, ss, sc, eh, em, es, ec;
00986     uint64_t start, end;
00987 
00988     if (sscanf(p, "%*[^,],%d:%d:%d%*c%d,%d:%d:%d%*c%d",
00989                &sh, &sm, &ss, &sc, &eh, &em, &es, &ec) != 8)
00990         return 0;
00991     start = 3600000*sh + 60000*sm + 1000*ss + 10*sc;
00992     end   = 3600000*eh + 60000*em + 1000*es + 10*ec;
00993     return end - start;
00994 }
00995 
00996 static int mkv_write_ass_blocks(AVFormatContext *s, AVIOContext *pb, AVPacket *pkt)
00997 {
00998     MatroskaMuxContext *mkv = s->priv_data;
00999     int i, layer = 0, max_duration = 0, size, line_size, data_size = pkt->size;
01000     uint8_t *start, *end, *data = pkt->data;
01001     ebml_master blockgroup;
01002     char buffer[2048];
01003 
01004     while (data_size) {
01005         int duration = ass_get_duration(data);
01006         max_duration = FFMAX(duration, max_duration);
01007         end = memchr(data, '\n', data_size);
01008         size = line_size = end ? end-data+1 : data_size;
01009         size -= end ? (end[-1]=='\r')+1 : 0;
01010         start = data;
01011         for (i=0; i<3; i++, start++)
01012             if (!(start = memchr(start, ',', size-(start-data))))
01013                 return max_duration;
01014         size -= start - data;
01015         sscanf(data, "Dialogue: %d,", &layer);
01016         i = snprintf(buffer, sizeof(buffer), "%"PRId64",%d,",
01017                      s->streams[pkt->stream_index]->nb_frames, layer);
01018         size = FFMIN(i+size, sizeof(buffer));
01019         memcpy(buffer+i, start, size-i);
01020 
01021         av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, "
01022                "pts %" PRId64 ", duration %d\n",
01023                avio_tell(pb), size, pkt->pts, duration);
01024         blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(size));
01025         put_ebml_id(pb, MATROSKA_ID_BLOCK);
01026         put_ebml_num(pb, size+4, 0);
01027         avio_w8(pb, 0x80 | (pkt->stream_index + 1));     // this assumes stream_index is less than 126
01028         avio_wb16(pb, pkt->pts - mkv->cluster_pts);
01029         avio_w8(pb, 0);
01030         avio_write(pb, buffer, size);
01031         put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
01032         end_ebml_master(pb, blockgroup);
01033 
01034         data += line_size;
01035         data_size -= line_size;
01036     }
01037 
01038     return max_duration;
01039 }
01040 
01041 static void mkv_write_block(AVFormatContext *s, AVIOContext *pb,
01042                             unsigned int blockid, AVPacket *pkt, int flags)
01043 {
01044     MatroskaMuxContext *mkv = s->priv_data;
01045     AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
01046     uint8_t *data = NULL;
01047     int size = pkt->size;
01048     int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts;
01049 
01050     av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, "
01051            "pts %" PRId64 ", dts %" PRId64 ", duration %d, flags %d\n",
01052            avio_tell(pb), pkt->size, pkt->pts, pkt->dts, pkt->duration, flags);
01053     if (codec->codec_id == CODEC_ID_H264 && codec->extradata_size > 0 &&
01054         (AV_RB24(codec->extradata) == 1 || AV_RB32(codec->extradata) == 1))
01055         ff_avc_parse_nal_units_buf(pkt->data, &data, &size);
01056     else
01057         data = pkt->data;
01058     put_ebml_id(pb, blockid);
01059     put_ebml_num(pb, size+4, 0);
01060     avio_w8(pb, 0x80 | (pkt->stream_index + 1));     // this assumes stream_index is less than 126
01061     avio_wb16(pb, ts - mkv->cluster_pts);
01062     avio_w8(pb, flags);
01063     avio_write(pb, data, size);
01064     if (data != pkt->data)
01065         av_free(data);
01066 }
01067 
01068 static int srt_get_duration(uint8_t **buf)
01069 {
01070     int i, duration = 0;
01071 
01072     for (i=0; i<2 && !duration; i++) {
01073         int s_hour, s_min, s_sec, s_hsec, e_hour, e_min, e_sec, e_hsec;
01074         if (sscanf(*buf, "%d:%2d:%2d%*1[,.]%3d --> %d:%2d:%2d%*1[,.]%3d",
01075                    &s_hour, &s_min, &s_sec, &s_hsec,
01076                    &e_hour, &e_min, &e_sec, &e_hsec) == 8) {
01077             s_min  +=   60*s_hour;      e_min  +=   60*e_hour;
01078             s_sec  +=   60*s_min;       e_sec  +=   60*e_min;
01079             s_hsec += 1000*s_sec;       e_hsec += 1000*e_sec;
01080             duration = e_hsec - s_hsec;
01081         }
01082         *buf += strcspn(*buf, "\n") + 1;
01083     }
01084     return duration;
01085 }
01086 
01087 static int mkv_write_srt_blocks(AVFormatContext *s, AVIOContext *pb, AVPacket *pkt)
01088 {
01089     ebml_master blockgroup;
01090     AVPacket pkt2 = *pkt;
01091     int64_t duration = srt_get_duration(&pkt2.data);
01092     pkt2.size -= pkt2.data - pkt->data;
01093 
01094     blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP,
01095                                    mkv_blockgroup_size(pkt2.size));
01096     mkv_write_block(s, pb, MATROSKA_ID_BLOCK, &pkt2, 0);
01097     put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
01098     end_ebml_master(pb, blockgroup);
01099 
01100     return duration;
01101 }
01102 
01103 static void mkv_flush_dynbuf(AVFormatContext *s)
01104 {
01105     MatroskaMuxContext *mkv = s->priv_data;
01106     int bufsize;
01107     uint8_t *dyn_buf;
01108 
01109     if (!mkv->dyn_bc)
01110         return;
01111 
01112     bufsize = avio_close_dyn_buf(mkv->dyn_bc, &dyn_buf);
01113     avio_write(s->pb, dyn_buf, bufsize);
01114     av_free(dyn_buf);
01115     mkv->dyn_bc = NULL;
01116 }
01117 
01118 static int mkv_write_packet_internal(AVFormatContext *s, AVPacket *pkt)
01119 {
01120     MatroskaMuxContext *mkv = s->priv_data;
01121     AVIOContext *pb = s->pb;
01122     AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
01123     int keyframe = !!(pkt->flags & AV_PKT_FLAG_KEY);
01124     int duration = pkt->duration;
01125     int ret;
01126     int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts;
01127 
01128     if (ts == AV_NOPTS_VALUE) {
01129         av_log(s, AV_LOG_ERROR, "Can't write packet with unknown timestamp\n");
01130         return AVERROR(EINVAL);
01131     }
01132 
01133     if (!s->pb->seekable) {
01134         if (!mkv->dyn_bc)
01135             avio_open_dyn_buf(&mkv->dyn_bc);
01136         pb = mkv->dyn_bc;
01137     }
01138 
01139     if (!mkv->cluster_pos) {
01140         mkv->cluster_pos = avio_tell(s->pb);
01141         mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER, 0);
01142         put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, FFMAX(0, ts));
01143         mkv->cluster_pts = FFMAX(0, ts);
01144     }
01145 
01146     if (codec->codec_type != AVMEDIA_TYPE_SUBTITLE) {
01147         mkv_write_block(s, pb, MATROSKA_ID_SIMPLEBLOCK, pkt, keyframe << 7);
01148     } else if (codec->codec_id == CODEC_ID_SSA) {
01149         duration = mkv_write_ass_blocks(s, pb, pkt);
01150     } else if (codec->codec_id == CODEC_ID_SRT) {
01151         duration = mkv_write_srt_blocks(s, pb, pkt);
01152     } else {
01153         ebml_master blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(pkt->size));
01154         duration = pkt->convergence_duration;
01155         mkv_write_block(s, pb, MATROSKA_ID_BLOCK, pkt, 0);
01156         put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
01157         end_ebml_master(pb, blockgroup);
01158     }
01159 
01160     if (codec->codec_type == AVMEDIA_TYPE_VIDEO && keyframe) {
01161         ret = mkv_add_cuepoint(mkv->cues, pkt->stream_index, ts, mkv->cluster_pos);
01162         if (ret < 0) return ret;
01163     }
01164 
01165     mkv->duration = FFMAX(mkv->duration, ts + duration);
01166     return 0;
01167 }
01168 
01169 static int mkv_copy_packet(MatroskaMuxContext *mkv, const AVPacket *pkt)
01170 {
01171     uint8_t *data           = mkv->cur_audio_pkt.data;
01172     mkv->cur_audio_pkt      = *pkt;
01173     mkv->cur_audio_pkt.data = av_fast_realloc(data, &mkv->audio_buffer_size, pkt->size);
01174     if (!mkv->cur_audio_pkt.data)
01175         return AVERROR(ENOMEM);
01176 
01177     memcpy(mkv->cur_audio_pkt.data, pkt->data, pkt->size);
01178     mkv->cur_audio_pkt.size = pkt->size;
01179     return 0;
01180 }
01181 
01182 static int mkv_write_packet(AVFormatContext *s, AVPacket *pkt)
01183 {
01184     MatroskaMuxContext *mkv = s->priv_data;
01185     AVIOContext *pb = s->pb->seekable ? s->pb : mkv->dyn_bc;
01186     AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
01187     int ret, keyframe = !!(pkt->flags & AV_PKT_FLAG_KEY);
01188     int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts;
01189     int cluster_size = avio_tell(pb) - (s->pb->seekable ? mkv->cluster_pos : 0);
01190 
01191     // start a new cluster every 5 MB or 5 sec, or 32k / 1 sec for streaming or
01192     // after 4k and on a keyframe
01193     if (mkv->cluster_pos &&
01194         ((!s->pb->seekable && (cluster_size > 32*1024 || ts > mkv->cluster_pts + 1000))
01195          ||                      cluster_size > 5*1024*1024 || ts > mkv->cluster_pts + 5000
01196          || (codec->codec_type == AVMEDIA_TYPE_VIDEO && keyframe && cluster_size > 4*1024))) {
01197         av_log(s, AV_LOG_DEBUG, "Starting new cluster at offset %" PRIu64
01198                " bytes, pts %" PRIu64 "\n", avio_tell(pb), ts);
01199         end_ebml_master(pb, mkv->cluster);
01200         mkv->cluster_pos = 0;
01201         if (mkv->dyn_bc)
01202             mkv_flush_dynbuf(s);
01203     }
01204 
01205     // check if we have an audio packet cached
01206     if (mkv->cur_audio_pkt.size > 0) {
01207         ret = mkv_write_packet_internal(s, &mkv->cur_audio_pkt);
01208         mkv->cur_audio_pkt.size = 0;
01209         if (ret < 0) {
01210             av_log(s, AV_LOG_ERROR, "Could not write cached audio packet ret:%d\n", ret);
01211             return ret;
01212         }
01213     }
01214 
01215     // buffer an audio packet to ensure the packet containing the video
01216     // keyframe's timecode is contained in the same cluster for WebM
01217     if (codec->codec_type == AVMEDIA_TYPE_AUDIO)
01218         ret = mkv_copy_packet(mkv, pkt);
01219     else
01220         ret = mkv_write_packet_internal(s, pkt);
01221     return ret;
01222 }
01223 
01224 static int mkv_write_trailer(AVFormatContext *s)
01225 {
01226     MatroskaMuxContext *mkv = s->priv_data;
01227     AVIOContext *pb = s->pb;
01228     int64_t currentpos, cuespos;
01229     int ret;
01230 
01231     // check if we have an audio packet cached
01232     if (mkv->cur_audio_pkt.size > 0) {
01233         ret = mkv_write_packet_internal(s, &mkv->cur_audio_pkt);
01234         mkv->cur_audio_pkt.size = 0;
01235         if (ret < 0) {
01236             av_log(s, AV_LOG_ERROR, "Could not write cached audio packet ret:%d\n", ret);
01237             return ret;
01238         }
01239     }
01240 
01241     if (mkv->dyn_bc) {
01242         end_ebml_master(mkv->dyn_bc, mkv->cluster);
01243         mkv_flush_dynbuf(s);
01244     } else if (mkv->cluster_pos) {
01245         end_ebml_master(pb, mkv->cluster);
01246     }
01247 
01248     if (pb->seekable) {
01249         if (mkv->cues->num_entries) {
01250             cuespos = mkv_write_cues(pb, mkv->cues, s->nb_streams);
01251 
01252             ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CUES, cuespos);
01253             if (ret < 0) return ret;
01254         }
01255 
01256         mkv_write_seekhead(pb, mkv->main_seekhead);
01257 
01258         // update the duration
01259         av_log(s, AV_LOG_DEBUG, "end duration = %" PRIu64 "\n", mkv->duration);
01260         currentpos = avio_tell(pb);
01261         avio_seek(pb, mkv->duration_offset, SEEK_SET);
01262         put_ebml_float(pb, MATROSKA_ID_DURATION, mkv->duration);
01263 
01264         avio_seek(pb, currentpos, SEEK_SET);
01265     }
01266 
01267     end_ebml_master(pb, mkv->segment);
01268     av_free(mkv->tracks);
01269     av_freep(&mkv->cues->entries);
01270     av_freep(&mkv->cues);
01271     av_destruct_packet(&mkv->cur_audio_pkt);
01272     avio_flush(pb);
01273     return 0;
01274 }
01275 
01276 static int mkv_query_codec(enum CodecID codec_id, int std_compliance)
01277 {
01278     int i;
01279     for (i = 0; ff_mkv_codec_tags[i].id != CODEC_ID_NONE; i++)
01280         if (ff_mkv_codec_tags[i].id == codec_id)
01281             return 1;
01282 
01283     if (std_compliance < FF_COMPLIANCE_NORMAL) {                // mkv theoretically supports any
01284         enum AVMediaType type = avcodec_get_type(codec_id);     // video/audio through VFW/ACM
01285         if (type == AVMEDIA_TYPE_VIDEO || type == AVMEDIA_TYPE_AUDIO)
01286             return 1;
01287     }
01288 
01289     return 0;
01290 }
01291 
01292 #if CONFIG_MATROSKA_MUXER
01293 AVOutputFormat ff_matroska_muxer = {
01294     .name              = "matroska",
01295     .long_name         = NULL_IF_CONFIG_SMALL("Matroska file format"),
01296     .mime_type         = "video/x-matroska",
01297     .extensions        = "mkv",
01298     .priv_data_size    = sizeof(MatroskaMuxContext),
01299 #if CONFIG_LIBVORBIS_ENCODER
01300     .audio_codec       = CODEC_ID_VORBIS,
01301 #else
01302     .audio_codec       = CODEC_ID_AC3,
01303 #endif
01304 #if CONFIG_LIBX264_ENCODER
01305     .video_codec       = CODEC_ID_H264,
01306 #else
01307     .video_codec       = CODEC_ID_MPEG4,
01308 #endif
01309     .write_header      = mkv_write_header,
01310     .write_packet      = mkv_write_packet,
01311     .write_trailer     = mkv_write_trailer,
01312     .flags             = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS,
01313     .codec_tag         = (const AVCodecTag* const []){ff_codec_bmp_tags, ff_codec_wav_tags, 0},
01314     .subtitle_codec    = CODEC_ID_SSA,
01315     .query_codec       = mkv_query_codec,
01316 };
01317 #endif
01318 
01319 #if CONFIG_WEBM_MUXER
01320 AVOutputFormat ff_webm_muxer = {
01321     .name              = "webm",
01322     .long_name         = NULL_IF_CONFIG_SMALL("WebM file format"),
01323     .mime_type         = "video/webm",
01324     .extensions        = "webm",
01325     .priv_data_size    = sizeof(MatroskaMuxContext),
01326     .audio_codec       = CODEC_ID_VORBIS,
01327     .video_codec       = CODEC_ID_VP8,
01328     .write_header      = mkv_write_header,
01329     .write_packet      = mkv_write_packet,
01330     .write_trailer     = mkv_write_trailer,
01331     .flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS,
01332 };
01333 #endif
01334 
01335 #if CONFIG_MATROSKA_AUDIO_MUXER
01336 AVOutputFormat ff_matroska_audio_muxer = {
01337     .name              = "matroska",
01338     .long_name         = NULL_IF_CONFIG_SMALL("Matroska file format"),
01339     .mime_type         = "audio/x-matroska",
01340     .extensions        = "mka",
01341     .priv_data_size    = sizeof(MatroskaMuxContext),
01342 #if CONFIG_LIBVORBIS_ENCODER
01343     .audio_codec       = CODEC_ID_VORBIS,
01344 #else
01345     .audio_codec       = CODEC_ID_AC3,
01346 #endif
01347     .video_codec       = CODEC_ID_NONE,
01348     .write_header      = mkv_write_header,
01349     .write_packet      = mkv_write_packet,
01350     .write_trailer     = mkv_write_trailer,
01351     .flags = AVFMT_GLOBALHEADER,
01352     .codec_tag = (const AVCodecTag* const []){ff_codec_wav_tags, 0},
01353 };
01354 #endif