1/* 2 * Ogg muxer 3 * Copyright (c) 2007 Baptiste Coudurier <baptiste dot coudurier at free dot fr> 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22#include "libavutil/crc.h" 23#include "libavcodec/xiph.h" 24#include "libavcodec/bytestream.h" 25#include "libavcodec/flac.h" 26#include "avformat.h" 27#include "internal.h" 28 29typedef struct { 30 int64_t duration; 31 unsigned page_counter; 32 uint8_t *header[3]; 33 int header_len[3]; 34 /** for theora granule */ 35 int kfgshift; 36 int64_t last_kf_pts; 37 int vrev; 38 int eos; 39} OGGStreamContext; 40 41static void ogg_update_checksum(AVFormatContext *s, int64_t crc_offset) 42{ 43 int64_t pos = url_ftell(s->pb); 44 uint32_t checksum = get_checksum(s->pb); 45 url_fseek(s->pb, crc_offset, SEEK_SET); 46 put_be32(s->pb, checksum); 47 url_fseek(s->pb, pos, SEEK_SET); 48} 49 50static int ogg_write_page(AVFormatContext *s, const uint8_t *data, int size, 51 int64_t granule, int stream_index, int flags) 52{ 53 OGGStreamContext *oggstream = s->streams[stream_index]->priv_data; 54 int64_t crc_offset; 55 int page_segments, i; 56 57 if (size >= 255*255) { 58 granule = -1; 59 size = 255*255; 60 } else if (oggstream->eos) 61 flags |= 4; 62 63 page_segments = FFMIN((size/255)+!!size, 255); 64 65 init_checksum(s->pb, ff_crc04C11DB7_update, 0); 66 put_tag(s->pb, "OggS"); 67 put_byte(s->pb, 0); 68 put_byte(s->pb, flags); 69 put_le64(s->pb, granule); 70 put_le32(s->pb, stream_index); 71 put_le32(s->pb, oggstream->page_counter++); 72 crc_offset = url_ftell(s->pb); 73 put_le32(s->pb, 0); // crc 74 put_byte(s->pb, page_segments); 75 for (i = 0; i < page_segments-1; i++) 76 put_byte(s->pb, 255); 77 if (size) { 78 put_byte(s->pb, size - (page_segments-1)*255); 79 put_buffer(s->pb, data, size); 80 } 81 ogg_update_checksum(s, crc_offset); 82 put_flush_packet(s->pb); 83 return size; 84} 85 86static int ogg_build_flac_headers(AVCodecContext *avctx, 87 OGGStreamContext *oggstream, int bitexact) 88{ 89 const char *vendor = bitexact ? "ffmpeg" : LIBAVFORMAT_IDENT; 90 enum FLACExtradataFormat format; 91 uint8_t *streaminfo; 92 uint8_t *p; 93 if (!ff_flac_is_extradata_valid(avctx, &format, &streaminfo)) 94 return -1; 95 oggstream->header_len[0] = 51; 96 oggstream->header[0] = av_mallocz(51); // per ogg flac specs 97 p = oggstream->header[0]; 98 bytestream_put_byte(&p, 0x7F); 99 bytestream_put_buffer(&p, "FLAC", 4); 100 bytestream_put_byte(&p, 1); // major version 101 bytestream_put_byte(&p, 0); // minor version 102 bytestream_put_be16(&p, 1); // headers packets without this one 103 bytestream_put_buffer(&p, "fLaC", 4); 104 bytestream_put_byte(&p, 0x00); // streaminfo 105 bytestream_put_be24(&p, 34); 106 bytestream_put_buffer(&p, streaminfo, FLAC_STREAMINFO_SIZE); 107 oggstream->header_len[1] = 1+3+4+strlen(vendor)+4; 108 oggstream->header[1] = av_mallocz(oggstream->header_len[1]); 109 p = oggstream->header[1]; 110 bytestream_put_byte(&p, 0x84); // last metadata block and vorbis comment 111 bytestream_put_be24(&p, oggstream->header_len[1] - 4); 112 bytestream_put_le32(&p, strlen(vendor)); 113 bytestream_put_buffer(&p, vendor, strlen(vendor)); 114 bytestream_put_le32(&p, 0); // user comment list length 115 return 0; 116} 117 118static int ogg_write_header(AVFormatContext *s) 119{ 120 OGGStreamContext *oggstream; 121 int i, j; 122 for (i = 0; i < s->nb_streams; i++) { 123 AVStream *st = s->streams[i]; 124 if (st->codec->codec_type == CODEC_TYPE_AUDIO) 125 av_set_pts_info(st, 64, 1, st->codec->sample_rate); 126 else if (st->codec->codec_type == CODEC_TYPE_VIDEO) 127 av_set_pts_info(st, 64, st->codec->time_base.num, st->codec->time_base.den); 128 if (st->codec->codec_id != CODEC_ID_VORBIS && 129 st->codec->codec_id != CODEC_ID_THEORA && 130 st->codec->codec_id != CODEC_ID_FLAC) { 131 av_log(s, AV_LOG_ERROR, "Unsupported codec id in stream %d\n", i); 132 return -1; 133 } 134 135 if (!st->codec->extradata || !st->codec->extradata_size) { 136 av_log(s, AV_LOG_ERROR, "No extradata present\n"); 137 return -1; 138 } 139 oggstream = av_mallocz(sizeof(*oggstream)); 140 st->priv_data = oggstream; 141 if (st->codec->codec_id == CODEC_ID_FLAC) { 142 if (ogg_build_flac_headers(st->codec, 143 oggstream, st->codec->flags & CODEC_FLAG_BITEXACT) < 0) { 144 av_log(s, AV_LOG_ERROR, "Extradata corrupted\n"); 145 av_freep(&st->priv_data); 146 } 147 } else { 148 if (ff_split_xiph_headers(st->codec->extradata, st->codec->extradata_size, 149 st->codec->codec_id == CODEC_ID_VORBIS ? 30 : 42, 150 oggstream->header, oggstream->header_len) < 0) { 151 av_log(s, AV_LOG_ERROR, "Extradata corrupted\n"); 152 av_freep(&st->priv_data); 153 return -1; 154 } 155 if (st->codec->codec_id == CODEC_ID_THEORA) { 156 /** KFGSHIFT is the width of the less significant section of the granule position 157 The less significant section is the frame count since the last keyframe */ 158 oggstream->kfgshift = ((oggstream->header[0][40]&3)<<3)|(oggstream->header[0][41]>>5); 159 oggstream->vrev = oggstream->header[0][9]; 160 av_log(s, AV_LOG_DEBUG, "theora kfgshift %d, vrev %d\n", 161 oggstream->kfgshift, oggstream->vrev); 162 } 163 } 164 } 165 for (i = 0; i < 3; i++) { 166 for (j = 0; j < s->nb_streams; j++) { 167 AVStream *st = s->streams[j]; 168 OGGStreamContext *oggstream = st->priv_data; 169 if (oggstream && oggstream->header_len[i]) { 170 ogg_write_page(s, oggstream->header[i], oggstream->header_len[i], 171 0, st->index, i ? 0 : 2); // bos 172 } 173 } 174 } 175 return 0; 176} 177 178static int ogg_write_packet(AVFormatContext *s, AVPacket *pkt) 179{ 180 AVStream *st = s->streams[pkt->stream_index]; 181 OGGStreamContext *oggstream = st->priv_data; 182 uint8_t *ptr = pkt->data; 183 int ret, size = pkt->size; 184 int64_t granule; 185 186 if (st->codec->codec_id == CODEC_ID_THEORA) { 187 int64_t pts = oggstream->vrev < 1 ? pkt->pts : pkt->pts + pkt->duration; 188 int pframe_count; 189 if (pkt->flags & PKT_FLAG_KEY) 190 oggstream->last_kf_pts = pts; 191 pframe_count = pts - oggstream->last_kf_pts; 192 // prevent frame count from overflow if key frame flag is not set 193 if (pframe_count >= (1<<oggstream->kfgshift)) { 194 oggstream->last_kf_pts += pframe_count; 195 pframe_count = 0; 196 } 197 granule = (oggstream->last_kf_pts<<oggstream->kfgshift) | pframe_count; 198 } else 199 granule = pkt->pts + pkt->duration; 200 oggstream->duration = granule; 201 do { 202 ret = ogg_write_page(s, ptr, size, granule, pkt->stream_index, ptr != pkt->data); 203 ptr += ret; size -= ret; 204 } while (size > 0 || ret == 255*255); // need to output a last nil page 205 206 return 0; 207} 208 209static int ogg_compare_granule(AVFormatContext *s, AVPacket *next, AVPacket *pkt) 210{ 211 AVStream *st2 = s->streams[next->stream_index]; 212 AVStream *st = s->streams[pkt ->stream_index]; 213 214 int64_t next_granule = av_rescale_q(next->pts + next->duration, 215 st2->time_base, AV_TIME_BASE_Q); 216 int64_t cur_granule = av_rescale_q(pkt ->pts + pkt ->duration, 217 st ->time_base, AV_TIME_BASE_Q); 218 return next_granule > cur_granule; 219} 220 221static int ogg_interleave_per_granule(AVFormatContext *s, AVPacket *out, AVPacket *pkt, int flush) 222{ 223 AVPacketList *pktl; 224 int stream_count = 0; 225 int streams[MAX_STREAMS] = {0}; 226 int interleaved = 0; 227 228 if (pkt) { 229 ff_interleave_add_packet(s, pkt, ogg_compare_granule); 230 } 231 232 pktl = s->packet_buffer; 233 while (pktl) { 234 if (streams[pktl->pkt.stream_index] == 0) 235 stream_count++; 236 streams[pktl->pkt.stream_index]++; 237 // need to buffer at least one packet to set eos flag 238 if (streams[pktl->pkt.stream_index] == 2) 239 interleaved++; 240 pktl = pktl->next; 241 } 242 243 if ((s->nb_streams == stream_count && interleaved == stream_count) || 244 (flush && stream_count)) { 245 pktl= s->packet_buffer; 246 *out= pktl->pkt; 247 s->packet_buffer = pktl->next; 248 if (flush && streams[out->stream_index] == 1) { 249 OGGStreamContext *ogg = s->streams[out->stream_index]->priv_data; 250 ogg->eos = 1; 251 } 252 av_freep(&pktl); 253 return 1; 254 } else { 255 av_init_packet(out); 256 return 0; 257 } 258} 259 260static int ogg_write_trailer(AVFormatContext *s) 261{ 262 int i; 263 for (i = 0; i < s->nb_streams; i++) { 264 AVStream *st = s->streams[i]; 265 OGGStreamContext *oggstream = st->priv_data; 266 if (st->codec->codec_id == CODEC_ID_FLAC) { 267 av_free(oggstream->header[0]); 268 av_free(oggstream->header[1]); 269 } 270 av_freep(&st->priv_data); 271 } 272 return 0; 273} 274 275AVOutputFormat ogg_muxer = { 276 "ogg", 277 NULL_IF_CONFIG_SMALL("Ogg"), 278 "application/ogg", 279 "ogg,ogv", 280 0, 281 CODEC_ID_FLAC, 282 CODEC_ID_THEORA, 283 ogg_write_header, 284 ogg_write_packet, 285 ogg_write_trailer, 286 .interleave_packet = ogg_interleave_per_granule, 287}; 288