diff options
Diffstat (limited to 'contrib/ffmpeg/libavformat/matroskaenc.c')
| -rw-r--r-- | contrib/ffmpeg/libavformat/matroskaenc.c | 845 |
1 files changed, 845 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavformat/matroskaenc.c b/contrib/ffmpeg/libavformat/matroskaenc.c new file mode 100644 index 000000000..d096f7204 --- /dev/null +++ b/contrib/ffmpeg/libavformat/matroskaenc.c @@ -0,0 +1,845 @@ +/* + * Matroska muxer + * Copyright (c) 2007 David Conrad + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include "avformat.h" +#include "md5.h" +#include "riff.h" +#include "xiph.h" +#include "matroska.h" +#include "avc.h" + +typedef struct ebml_master { + offset_t pos; ///< absolute offset in the file where the master's elements start + int sizebytes; ///< how many bytes were reserved for the size +} ebml_master; + +typedef struct mkv_seekhead_entry { + unsigned int elementid; + uint64_t segmentpos; +} mkv_seekhead_entry; + +typedef struct mkv_seekhead { + offset_t filepos; + offset_t segment_offset; ///< the file offset to the beginning of the segment + int reserved_size; ///< -1 if appending to file + int max_entries; + mkv_seekhead_entry *entries; + int num_entries; +} mkv_seekhead; + +typedef struct { + uint64_t pts; + int tracknum; + offset_t cluster_pos; ///< file offset of the cluster containing the block +} mkv_cuepoint; + +typedef struct { + offset_t segment_offset; + mkv_cuepoint *entries; + int num_entries; +} mkv_cues; + +typedef struct MatroskaMuxContext { + ebml_master segment; + offset_t segment_offset; + offset_t segment_uid; + ebml_master cluster; + offset_t cluster_pos; ///< file offset of the current cluster + uint64_t cluster_pts; + offset_t duration_offset; + uint64_t duration; + mkv_seekhead *main_seekhead; + mkv_seekhead *cluster_seekhead; + mkv_cues *cues; + + struct AVMD5 *md5_ctx; +} MatroskaMuxContext; + + +/** 2 bytes * 3 for EBML IDs, 3 1-byte EBML lengths, 8 bytes for 64 bit + * offset, 4 bytes for target EBML ID */ +#define MAX_SEEKENTRY_SIZE 21 + +/** per-cuepoint-track - 3 1-byte EBML IDs, 3 1-byte EBML sizes, 2 + * 8-byte uint max */ +#define MAX_CUETRACKPOS_SIZE 22 + +/** per-cuepoint - 2 1-byte EBML IDs, 2 1-byte EBML sizes, 8-byte uint max */ +#define MAX_CUEPOINT_SIZE(num_tracks) 12 + MAX_CUETRACKPOS_SIZE*num_tracks + + +static int ebml_id_size(unsigned int id) +{ + return (av_log2(id+1)-1)/7+1; +} + +static void put_ebml_id(ByteIOContext *pb, unsigned int id) +{ + int i = ebml_id_size(id); + while (i--) + put_byte(pb, id >> (i*8)); +} + +/** + * Write an EBML size meaning "unknown size". + * + * @param bytes The number of bytes the size should occupy (maximum: 8). + */ +static void put_ebml_size_unknown(ByteIOContext *pb, int bytes) +{ + assert(bytes <= 8); + put_byte(pb, 0x1ff >> bytes); + while (--bytes) + put_byte(pb, 0xff); +} + +/** + * Calculate how many bytes are needed to represent a given number in EBML. + */ +static int ebml_num_size(uint64_t num) +{ + int bytes = 1; + while ((num+1) >> bytes*7) bytes++; + return bytes; +} + +/** + * Write a number in EBML variable length format. + * + * @param bytes The number of bytes that need to be used to write the number. + * If zero, any number of bytes can be used. + */ +static void put_ebml_num(ByteIOContext *pb, uint64_t num, int bytes) +{ + int i, needed_bytes = ebml_num_size(num); + + // sizes larger than this are currently undefined in EBML + assert(num < (1ULL<<56)-1); + + if (bytes == 0) + // don't care how many bytes are used, so use the min + bytes = needed_bytes; + // the bytes needed to write the given size would exceed the bytes + // that we need to use, so write unknown size. This shouldn't happen. + assert(bytes >= needed_bytes); + + num |= 1ULL << bytes*7; + for (i = bytes - 1; i >= 0; i--) + put_byte(pb, num >> i*8); +} + +static void put_ebml_uint(ByteIOContext *pb, unsigned int elementid, uint64_t val) +{ + int i, bytes = 1; + uint64_t tmp = val; + while (tmp>>=8) bytes++; + + put_ebml_id(pb, elementid); + put_ebml_num(pb, bytes, 0); + for (i = bytes - 1; i >= 0; i--) + put_byte(pb, val >> i*8); +} + +static void put_ebml_float(ByteIOContext *pb, unsigned int elementid, double val) +{ + put_ebml_id(pb, elementid); + put_ebml_num(pb, 8, 0); + put_be64(pb, av_dbl2int(val)); +} + +static void put_ebml_binary(ByteIOContext *pb, unsigned int elementid, + const uint8_t *buf, int size) +{ + put_ebml_id(pb, elementid); + put_ebml_num(pb, size, 0); + put_buffer(pb, buf, size); +} + +static void put_ebml_string(ByteIOContext *pb, unsigned int elementid, const char *str) +{ + put_ebml_binary(pb, elementid, str, strlen(str)); +} + +/** + * Writes a void element of a given size. Useful for reserving space in + * the file to be written to later. + * + * @param size The number of bytes to reserve, which must be at least 2. + */ +static void put_ebml_void(ByteIOContext *pb, uint64_t size) +{ + offset_t currentpos = url_ftell(pb); + + assert(size >= 2); + + put_ebml_id(pb, EBML_ID_VOID); + // we need to subtract the length needed to store the size from the + // size we need to reserve so 2 cases, we use 8 bytes to store the + // size if possible, 1 byte otherwise + if (size < 10) + put_ebml_num(pb, size-1, 0); + else + put_ebml_num(pb, size-9, 8); + while(url_ftell(pb) < currentpos + size) + put_byte(pb, 0); +} + +static ebml_master start_ebml_master(ByteIOContext *pb, unsigned int elementid, uint64_t expectedsize) +{ + int bytes = expectedsize ? ebml_num_size(expectedsize) : 8; + put_ebml_id(pb, elementid); + put_ebml_size_unknown(pb, bytes); + return (ebml_master){ url_ftell(pb), bytes }; +} + +static void end_ebml_master(ByteIOContext *pb, ebml_master master) +{ + offset_t pos = url_ftell(pb); + + // leave the unknown size for masters when streaming + if (url_is_streamed(pb)) + return; + + url_fseek(pb, master.pos - master.sizebytes, SEEK_SET); + put_ebml_num(pb, pos - master.pos, master.sizebytes); + url_fseek(pb, pos, SEEK_SET); +} + +static void put_xiph_size(ByteIOContext *pb, int size) +{ + int i; + for (i = 0; i < size / 255; i++) + put_byte(pb, 255); + put_byte(pb, size % 255); +} + +/** + * Initialize a mkv_seekhead element to be ready to index level 1 Matroska + * elements. If a maximum number of elements is specified, enough space + * will be reserved at the current file location to write a seek head of + * that size. + * + * @param segment_offset The absolute offset to the position in the file + * where the segment begins. + * @param numelements The maximum number of elements that will be indexed + * by this seek head, 0 if unlimited. + */ +static mkv_seekhead * mkv_start_seekhead(ByteIOContext *pb, offset_t segment_offset, int numelements) +{ + mkv_seekhead *new_seekhead = av_mallocz(sizeof(mkv_seekhead)); + if (new_seekhead == NULL) + return NULL; + + new_seekhead->segment_offset = segment_offset; + + if (numelements > 0) { + new_seekhead->filepos = url_ftell(pb); + // 21 bytes max for a seek entry, 10 bytes max for the SeekHead ID + // and size, and 3 bytes to guarantee that an EBML void element + // will fit afterwards + new_seekhead->reserved_size = numelements * MAX_SEEKENTRY_SIZE + 13; + new_seekhead->max_entries = numelements; + put_ebml_void(pb, new_seekhead->reserved_size); + } + return new_seekhead; +} + +static int mkv_add_seekhead_entry(mkv_seekhead *seekhead, unsigned int elementid, uint64_t filepos) +{ + mkv_seekhead_entry *entries = seekhead->entries; + + // don't store more elements than we reserved space for + if (seekhead->max_entries > 0 && seekhead->max_entries <= seekhead->num_entries) + return -1; + + entries = av_realloc(entries, (seekhead->num_entries + 1) * sizeof(mkv_seekhead_entry)); + if (entries == NULL) + return AVERROR(ENOMEM); + + entries[seekhead->num_entries ].elementid = elementid; + entries[seekhead->num_entries++].segmentpos = filepos - seekhead->segment_offset; + + seekhead->entries = entries; + return 0; +} + +/** + * Write the seek head to the file and free it. If a maximum number of + * elements was specified to mkv_start_seekhead(), the seek head will + * be written at the location reserved for it. Otherwise, it is written + * at the current location in the file. + * + * @return The file offset where the seekhead was written. + */ +static offset_t mkv_write_seekhead(ByteIOContext *pb, mkv_seekhead *seekhead) +{ + ebml_master metaseek, seekentry; + offset_t currentpos; + int i; + + currentpos = url_ftell(pb); + + if (seekhead->reserved_size > 0) + url_fseek(pb, seekhead->filepos, SEEK_SET); + + metaseek = start_ebml_master(pb, MATROSKA_ID_SEEKHEAD, seekhead->reserved_size); + for (i = 0; i < seekhead->num_entries; i++) { + mkv_seekhead_entry *entry = &seekhead->entries[i]; + + seekentry = start_ebml_master(pb, MATROSKA_ID_SEEKENTRY, MAX_SEEKENTRY_SIZE); + + put_ebml_id(pb, MATROSKA_ID_SEEKID); + put_ebml_num(pb, ebml_id_size(entry->elementid), 0); + put_ebml_id(pb, entry->elementid); + + put_ebml_uint(pb, MATROSKA_ID_SEEKPOSITION, entry->segmentpos); + end_ebml_master(pb, seekentry); + } + end_ebml_master(pb, metaseek); + + if (seekhead->reserved_size > 0) { + uint64_t remaining = seekhead->filepos + seekhead->reserved_size - url_ftell(pb); + put_ebml_void(pb, remaining); + url_fseek(pb, currentpos, SEEK_SET); + + currentpos = seekhead->filepos; + } + av_free(seekhead->entries); + av_free(seekhead); + + return currentpos; +} + +static mkv_cues * mkv_start_cues(offset_t segment_offset) +{ + mkv_cues *cues = av_mallocz(sizeof(mkv_cues)); + if (cues == NULL) + return NULL; + + cues->segment_offset = segment_offset; + return cues; +} + +static int mkv_add_cuepoint(mkv_cues *cues, AVPacket *pkt, offset_t cluster_pos) +{ + mkv_cuepoint *entries = cues->entries; + + entries = av_realloc(entries, (cues->num_entries + 1) * sizeof(mkv_cuepoint)); + if (entries == NULL) + return AVERROR(ENOMEM); + + entries[cues->num_entries ].pts = pkt->pts; + entries[cues->num_entries ].tracknum = pkt->stream_index + 1; + entries[cues->num_entries++].cluster_pos = cluster_pos - cues->segment_offset; + + cues->entries = entries; + return 0; +} + +static offset_t mkv_write_cues(ByteIOContext *pb, mkv_cues *cues, int num_tracks) +{ + ebml_master cues_element; + offset_t currentpos; + int i, j; + + currentpos = url_ftell(pb); + cues_element = start_ebml_master(pb, MATROSKA_ID_CUES, 0); + + for (i = 0; i < cues->num_entries; i++) { + ebml_master cuepoint, track_positions; + mkv_cuepoint *entry = &cues->entries[i]; + uint64_t pts = entry->pts; + + cuepoint = start_ebml_master(pb, MATROSKA_ID_POINTENTRY, MAX_CUEPOINT_SIZE(num_tracks)); + put_ebml_uint(pb, MATROSKA_ID_CUETIME, pts); + + // put all the entries from different tracks that have the exact same + // timestamp into the same CuePoint + for (j = 0; j < cues->num_entries - i && entry[j].pts == pts; j++) { + track_positions = start_ebml_master(pb, MATROSKA_ID_CUETRACKPOSITION, MAX_CUETRACKPOS_SIZE); + put_ebml_uint(pb, MATROSKA_ID_CUETRACK , entry[j].tracknum ); + put_ebml_uint(pb, MATROSKA_ID_CUECLUSTERPOSITION, entry[j].cluster_pos); + end_ebml_master(pb, track_positions); + } + i += j - 1; + end_ebml_master(pb, cuepoint); + } + end_ebml_master(pb, cues_element); + + av_free(cues->entries); + av_free(cues); + return currentpos; +} + +static int put_xiph_codecpriv(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec) +{ + uint8_t *header_start[3]; + int header_len[3]; + int first_header_size; + int j; + + if (codec->codec_id == CODEC_ID_VORBIS) + first_header_size = 30; + else + first_header_size = 42; + + if (ff_split_xiph_headers(codec->extradata, codec->extradata_size, + first_header_size, header_start, header_len) < 0) { + av_log(s, AV_LOG_ERROR, "Extradata corrupt.\n"); + return -1; + } + + put_byte(pb, 2); // number packets - 1 + for (j = 0; j < 2; j++) { + put_xiph_size(pb, header_len[j]); + } + for (j = 0; j < 3; j++) + put_buffer(pb, header_start[j], header_len[j]); + + return 0; +} + +#define FLAC_STREAMINFO_SIZE 34 + +static int put_flac_codecpriv(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec) +{ + // if the extradata_size is greater than FLAC_STREAMINFO_SIZE, + // assume that it's in Matroska's format already + if (codec->extradata_size < FLAC_STREAMINFO_SIZE) { + av_log(s, AV_LOG_ERROR, "Invalid FLAC extradata\n"); + return -1; + } else if (codec->extradata_size == FLAC_STREAMINFO_SIZE) { + // only the streaminfo packet + put_byte(pb, 0); + put_xiph_size(pb, codec->extradata_size); + av_log(s, AV_LOG_ERROR, "Only one packet\n"); + } + put_buffer(pb, codec->extradata, codec->extradata_size); + return 0; +} + +static void get_aac_sample_rates(AVFormatContext *s, AVCodecContext *codec, int *sample_rate, int *output_sample_rate) +{ + static const int aac_sample_rates[] = { + 96000, 88200, 64000, 48000, 44100, 32000, + 24000, 22050, 16000, 12000, 11025, 8000, + }; + int sri; + + if (codec->extradata_size < 2) { + av_log(s, AV_LOG_WARNING, "No AAC extradata, unable to determine samplerate.\n"); + return; + } + + sri = ((codec->extradata[0] << 1) & 0xE) | (codec->extradata[1] >> 7); + if (sri > 12) { + av_log(s, AV_LOG_WARNING, "AAC samplerate index out of bounds\n"); + return; + } + *sample_rate = aac_sample_rates[sri]; + + // if sbr, get output sample rate as well + if (codec->extradata_size == 5) { + sri = (codec->extradata[4] >> 3) & 0xF; + if (sri > 12) { + av_log(s, AV_LOG_WARNING, "AAC output samplerate index out of bounds\n"); + return; + } + *output_sample_rate = aac_sample_rates[sri]; + } +} + +static int mkv_write_codecprivate(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec, int native_id) +{ + ByteIOContext *dyn_cp; + uint8_t *codecpriv; + int ret, codecpriv_size; + + ret = url_open_dyn_buf(&dyn_cp); + if(ret < 0) + return ret; + + if (native_id) { + if (codec->codec_id == CODEC_ID_VORBIS || codec->codec_id == CODEC_ID_THEORA) + ret = put_xiph_codecpriv(s, dyn_cp, codec); + else if (codec->codec_id == CODEC_ID_FLAC) + ret = put_flac_codecpriv(s, dyn_cp, codec); + else if (codec->codec_id == CODEC_ID_H264) + ret = ff_isom_write_avcc(dyn_cp, codec->extradata, codec->extradata_size); + else if (codec->extradata_size) + put_buffer(dyn_cp, codec->extradata, codec->extradata_size); + } else if (codec->codec_type == CODEC_TYPE_VIDEO) { + if (!codec->codec_tag) + codec->codec_tag = codec_get_tag(codec_bmp_tags, codec->codec_id); + if (!codec->codec_tag) { + av_log(s, AV_LOG_ERROR, "No bmp codec ID found."); + ret = -1; + } + + put_bmp_header(dyn_cp, codec, codec_bmp_tags, 0); + + } else if (codec->codec_type == CODEC_TYPE_AUDIO) { + if (!codec->codec_tag) + codec->codec_tag = codec_get_tag(codec_wav_tags, codec->codec_id); + if (!codec->codec_tag) { + av_log(s, AV_LOG_ERROR, "No wav codec ID found."); + ret = -1; + } + + put_wav_header(dyn_cp, codec); + } + + codecpriv_size = url_close_dyn_buf(dyn_cp, &codecpriv); + if (codecpriv_size) + put_ebml_binary(pb, MATROSKA_ID_CODECPRIVATE, codecpriv, codecpriv_size); + av_free(codecpriv); + return ret; +} + +static int mkv_write_tracks(AVFormatContext *s) +{ + MatroskaMuxContext *mkv = s->priv_data; + ByteIOContext *pb = s->pb; + ebml_master tracks; + int i, j, ret; + + ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_TRACKS, url_ftell(pb)); + if (ret < 0) return ret; + + tracks = start_ebml_master(pb, MATROSKA_ID_TRACKS, 0); + for (i = 0; i < s->nb_streams; i++) { + AVStream *st = s->streams[i]; + AVCodecContext *codec = st->codec; + ebml_master subinfo, track; + int native_id = 0; + int bit_depth = av_get_bits_per_sample(codec->codec_id); + int sample_rate = codec->sample_rate; + int output_sample_rate = 0; + + if (!bit_depth) + bit_depth = av_get_bits_per_sample_format(codec->sample_fmt); + + if (codec->codec_id == CODEC_ID_AAC) + get_aac_sample_rates(s, codec, &sample_rate, &output_sample_rate); + + track = start_ebml_master(pb, MATROSKA_ID_TRACKENTRY, 0); + put_ebml_uint (pb, MATROSKA_ID_TRACKNUMBER , i + 1); + put_ebml_uint (pb, MATROSKA_ID_TRACKUID , i + 1); + put_ebml_uint (pb, MATROSKA_ID_TRACKFLAGLACING , 0); // no lacing (yet) + + if (st->language[0]) + put_ebml_string(pb, MATROSKA_ID_TRACKLANGUAGE, st->language); + else + put_ebml_string(pb, MATROSKA_ID_TRACKLANGUAGE, "und"); + + // look for a codec ID string specific to mkv to use, + // if none are found, use AVI codes + for (j = 0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++) { + if (ff_mkv_codec_tags[j].id == codec->codec_id) { + put_ebml_string(pb, MATROSKA_ID_CODECID, ff_mkv_codec_tags[j].str); + native_id = 1; + break; + } + } + + switch (codec->codec_type) { + case CODEC_TYPE_VIDEO: + put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_VIDEO); + + if (!native_id) + // if there is no mkv-specific codec ID, use VFW mode + put_ebml_string(pb, MATROSKA_ID_CODECID, MATROSKA_CODEC_ID_VIDEO_VFW_FOURCC); + + subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKVIDEO, 0); + // XXX: interlace flag? + put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELWIDTH , codec->width); + put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELHEIGHT, codec->height); + if (codec->sample_aspect_ratio.num) { + AVRational dar = av_mul_q(codec->sample_aspect_ratio, + (AVRational){codec->width, codec->height}); + put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYWIDTH , dar.num); + put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYHEIGHT, dar.den); + } + end_ebml_master(pb, subinfo); + break; + + case CODEC_TYPE_AUDIO: + put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_AUDIO); + + if (!native_id) + // no mkv-specific ID, use ACM mode + put_ebml_string(pb, MATROSKA_ID_CODECID, MATROSKA_CODEC_ID_AUDIO_ACM); + + subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKAUDIO, 0); + put_ebml_uint (pb, MATROSKA_ID_AUDIOCHANNELS , codec->channels); + put_ebml_float (pb, MATROSKA_ID_AUDIOSAMPLINGFREQ, sample_rate); + if (output_sample_rate) + put_ebml_float(pb, MATROSKA_ID_AUDIOOUTSAMPLINGFREQ, output_sample_rate); + if (bit_depth) + put_ebml_uint(pb, MATROSKA_ID_AUDIOBITDEPTH, bit_depth); + end_ebml_master(pb, subinfo); + break; + + case CODEC_TYPE_SUBTITLE: + put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_SUBTITLE); + break; + default: + av_log(s, AV_LOG_ERROR, "Only audio, video, and subtitles are supported for Matroska."); + break; + } + ret = mkv_write_codecprivate(s, pb, codec, native_id); + if (ret < 0) return ret; + + end_ebml_master(pb, track); + + // ms precision is the de-facto standard timescale for mkv files + av_set_pts_info(st, 64, 1, 1000); + } + end_ebml_master(pb, tracks); + return 0; +} + +static int mkv_write_header(AVFormatContext *s) +{ + MatroskaMuxContext *mkv = s->priv_data; + ByteIOContext *pb = s->pb; + ebml_master ebml_header, segment_info; + int ret; + + mkv->md5_ctx = av_mallocz(av_md5_size); + av_md5_init(mkv->md5_ctx); + + ebml_header = start_ebml_master(pb, EBML_ID_HEADER, 0); + put_ebml_uint (pb, EBML_ID_EBMLVERSION , 1); + put_ebml_uint (pb, EBML_ID_EBMLREADVERSION , 1); + put_ebml_uint (pb, EBML_ID_EBMLMAXIDLENGTH , 4); + put_ebml_uint (pb, EBML_ID_EBMLMAXSIZELENGTH , 8); + put_ebml_string (pb, EBML_ID_DOCTYPE , "matroska"); + put_ebml_uint (pb, EBML_ID_DOCTYPEVERSION , 2); + put_ebml_uint (pb, EBML_ID_DOCTYPEREADVERSION , 2); + end_ebml_master(pb, ebml_header); + + mkv->segment = start_ebml_master(pb, MATROSKA_ID_SEGMENT, 0); + mkv->segment_offset = url_ftell(pb); + + // we write 2 seek heads - one at the end of the file to point to each + // cluster, and one at the beginning to point to all other level one + // elements (including the seek head at the end of the file), which + // isn't more than 10 elements if we only write one of each other + // currently defined level 1 element + mkv->main_seekhead = mkv_start_seekhead(pb, mkv->segment_offset, 10); + mkv->cluster_seekhead = mkv_start_seekhead(pb, mkv->segment_offset, 0); + if (mkv->main_seekhead == NULL || mkv->cluster_seekhead == NULL) + return AVERROR(ENOMEM); + + ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_INFO, url_ftell(pb)); + if (ret < 0) return ret; + + segment_info = start_ebml_master(pb, MATROSKA_ID_INFO, 0); + put_ebml_uint(pb, MATROSKA_ID_TIMECODESCALE, 1000000); + if (strlen(s->title)) + put_ebml_string(pb, MATROSKA_ID_TITLE, s->title); + if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) { + put_ebml_string(pb, MATROSKA_ID_MUXINGAPP , LIBAVFORMAT_IDENT); + put_ebml_string(pb, MATROSKA_ID_WRITINGAPP, LIBAVFORMAT_IDENT); + + // reserve space to write the segment UID later + mkv->segment_uid = url_ftell(pb); + put_ebml_void(pb, 19); + } + + // reserve space for the duration + mkv->duration = 0; + mkv->duration_offset = url_ftell(pb); + put_ebml_void(pb, 11); // assumes double-precision float to be written + end_ebml_master(pb, segment_info); + + ret = mkv_write_tracks(s); + if (ret < 0) return ret; + + ret = mkv_add_seekhead_entry(mkv->cluster_seekhead, MATROSKA_ID_CLUSTER, url_ftell(pb)); + if (ret < 0) return ret; + + mkv->cluster_pos = url_ftell(pb); + mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER, 0); + put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, 0); + mkv->cluster_pts = 0; + + mkv->cues = mkv_start_cues(mkv->segment_offset); + if (mkv->cues == NULL) + return AVERROR(ENOMEM); + + return 0; +} + +static int mkv_block_size(AVPacket *pkt) +{ + int size = 4; // track num + timecode + flags + return size + pkt->size; +} + +static int mkv_blockgroup_size(AVPacket *pkt) +{ + int size = mkv_block_size(pkt); + size += ebml_num_size(size); + size += 2; // EBML ID for block and block duration + size += 8; // max size of block duration + size += ebml_num_size(size); + size += 1; // blockgroup EBML ID + return size; +} + +static void mkv_write_block(AVFormatContext *s, unsigned int blockid, AVPacket *pkt, int flags) +{ + MatroskaMuxContext *mkv = s->priv_data; + ByteIOContext *pb = s->pb; + + av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, " + "pts %" PRId64 ", dts %" PRId64 ", duration %d, flags %d\n", + url_ftell(pb), pkt->size, pkt->pts, pkt->dts, pkt->duration, flags); + put_ebml_id(pb, blockid); + put_ebml_num(pb, mkv_block_size(pkt), 0); + put_byte(pb, 0x80 | (pkt->stream_index + 1)); // this assumes stream_index is less than 126 + put_be16(pb, pkt->pts - mkv->cluster_pts); + put_byte(pb, flags); + put_buffer(pb, pkt->data, pkt->size); +} + +static int mkv_write_packet(AVFormatContext *s, AVPacket *pkt) +{ + MatroskaMuxContext *mkv = s->priv_data; + ByteIOContext *pb = s->pb; + AVCodecContext *codec = s->streams[pkt->stream_index]->codec; + int keyframe = !!(pkt->flags & PKT_FLAG_KEY); + int ret; + + // start a new cluster every 5 MB or 5 sec + if (url_ftell(pb) > mkv->cluster_pos + 5*1024*1024 || pkt->pts > mkv->cluster_pts + 5000) { + av_log(s, AV_LOG_DEBUG, "Starting new cluster at offset %" PRIu64 + " bytes, pts %" PRIu64 "\n", url_ftell(pb), pkt->pts); + end_ebml_master(pb, mkv->cluster); + + ret = mkv_add_seekhead_entry(mkv->cluster_seekhead, MATROSKA_ID_CLUSTER, url_ftell(pb)); + if (ret < 0) return ret; + + mkv->cluster_pos = url_ftell(pb); + mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER, 0); + put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, pkt->pts); + mkv->cluster_pts = pkt->pts; + av_md5_update(mkv->md5_ctx, pkt->data, FFMIN(200, pkt->size)); + } + + if (codec->codec_id == CODEC_ID_H264 && + codec->extradata_size > 0 && AV_RB32(codec->extradata) == 0x00000001) { + /* from x264 or from bytestream h264 */ + /* nal reformating needed */ + int ret = ff_avc_parse_nal_units(pkt->data, &pkt->data, &pkt->size); + if (ret < 0) + return ret; + assert(pkt->size); + } + + if (codec->codec_type != CODEC_TYPE_SUBTITLE) { + mkv_write_block(s, MATROSKA_ID_SIMPLEBLOCK, pkt, keyframe << 7); + } else { + ebml_master blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(pkt)); + mkv_write_block(s, MATROSKA_ID_BLOCK, pkt, 0); + put_ebml_uint(pb, MATROSKA_ID_DURATION, pkt->duration); + end_ebml_master(pb, blockgroup); + } + + if (codec->codec_type == CODEC_TYPE_VIDEO && keyframe) { + ret = mkv_add_cuepoint(mkv->cues, pkt, mkv->cluster_pos); + if (ret < 0) return ret; + } + + mkv->duration = FFMAX(mkv->duration, pkt->pts + pkt->duration); + return 0; +} + +static int mkv_write_trailer(AVFormatContext *s) +{ + MatroskaMuxContext *mkv = s->priv_data; + ByteIOContext *pb = s->pb; + offset_t currentpos, second_seekhead, cuespos; + int ret; + + end_ebml_master(pb, mkv->cluster); + + if (!url_is_streamed(pb)) { + cuespos = mkv_write_cues(pb, mkv->cues, s->nb_streams); + second_seekhead = mkv_write_seekhead(pb, mkv->cluster_seekhead); + + ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CUES , cuespos); + if (ret < 0) return ret; + ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_SEEKHEAD, second_seekhead); + if (ret < 0) return ret; + mkv_write_seekhead(pb, mkv->main_seekhead); + + // update the duration + av_log(s, AV_LOG_DEBUG, "end duration = %" PRIu64 "\n", mkv->duration); + currentpos = url_ftell(pb); + url_fseek(pb, mkv->duration_offset, SEEK_SET); + put_ebml_float(pb, MATROSKA_ID_DURATION, mkv->duration); + + // write the md5sum of some frames as the segment UID + if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) { + uint8_t segment_uid[16]; + av_md5_final(mkv->md5_ctx, segment_uid); + url_fseek(pb, mkv->segment_uid, SEEK_SET); + put_ebml_binary(pb, MATROSKA_ID_SEGMENTUID, segment_uid, 16); + } + url_fseek(pb, currentpos, SEEK_SET); + } + + end_ebml_master(pb, mkv->segment); + av_free(mkv->md5_ctx); + return 0; +} + +AVOutputFormat matroska_muxer = { + "matroska", + "Matroska File Format", + "video/x-matroska", + "mkv", + sizeof(MatroskaMuxContext), + CODEC_ID_MP2, + CODEC_ID_MPEG4, + mkv_write_header, + mkv_write_packet, + mkv_write_trailer, + .codec_tag = (const AVCodecTag*[]){codec_bmp_tags, codec_wav_tags, 0}, + .subtitle_codec = CODEC_ID_TEXT, +}; + +AVOutputFormat matroska_audio_muxer = { + "matroska", + "Matroska File Format", + "audio/x-matroska", + "mka", + sizeof(MatroskaMuxContext), + CODEC_ID_MP2, + CODEC_ID_NONE, + mkv_write_header, + mkv_write_packet, + mkv_write_trailer, + .codec_tag = (const AVCodecTag*[]){codec_wav_tags, 0}, +}; 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