1/* 2 * FFM (ffserver live feed) demuxer 3 * Copyright (c) 2001 Fabrice Bellard 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/intreadwrite.h" 23#include "avformat.h" 24#include "ffm.h" 25#if CONFIG_FFSERVER 26#include <unistd.h> 27 28int64_t ffm_read_write_index(int fd) 29{ 30 uint8_t buf[8]; 31 32 lseek(fd, 8, SEEK_SET); 33 if (read(fd, buf, 8) != 8) 34 return AVERROR(EIO); 35 return AV_RB64(buf); 36} 37 38int ffm_write_write_index(int fd, int64_t pos) 39{ 40 uint8_t buf[8]; 41 int i; 42 43 for(i=0;i<8;i++) 44 buf[i] = (pos >> (56 - i * 8)) & 0xff; 45 lseek(fd, 8, SEEK_SET); 46 if (write(fd, buf, 8) != 8) 47 return AVERROR(EIO); 48 return 8; 49} 50 51void ffm_set_write_index(AVFormatContext *s, int64_t pos, int64_t file_size) 52{ 53 FFMContext *ffm = s->priv_data; 54 ffm->write_index = pos; 55 ffm->file_size = file_size; 56} 57#endif // CONFIG_FFSERVER 58 59static int ffm_is_avail_data(AVFormatContext *s, int size) 60{ 61 FFMContext *ffm = s->priv_data; 62 int64_t pos, avail_size; 63 int len; 64 65 len = ffm->packet_end - ffm->packet_ptr; 66 if (size <= len) 67 return 1; 68 pos = url_ftell(s->pb); 69 if (!ffm->write_index) { 70 if (pos == ffm->file_size) 71 return AVERROR_EOF; 72 avail_size = ffm->file_size - pos; 73 } else { 74 if (pos == ffm->write_index) { 75 /* exactly at the end of stream */ 76 return AVERROR(EAGAIN); 77 } else if (pos < ffm->write_index) { 78 avail_size = ffm->write_index - pos; 79 } else { 80 avail_size = (ffm->file_size - pos) + (ffm->write_index - FFM_PACKET_SIZE); 81 } 82 } 83 avail_size = (avail_size / ffm->packet_size) * (ffm->packet_size - FFM_HEADER_SIZE) + len; 84 if (size <= avail_size) 85 return 1; 86 else 87 return AVERROR(EAGAIN); 88} 89 90static int ffm_resync(AVFormatContext *s, int state) 91{ 92 av_log(s, AV_LOG_ERROR, "resyncing\n"); 93 while (state != PACKET_ID) { 94 if (url_feof(s->pb)) { 95 av_log(s, AV_LOG_ERROR, "cannot find FFM syncword\n"); 96 return -1; 97 } 98 state = (state << 8) | get_byte(s->pb); 99 } 100 return 0; 101} 102 103/* first is true if we read the frame header */ 104static int ffm_read_data(AVFormatContext *s, 105 uint8_t *buf, int size, int header) 106{ 107 FFMContext *ffm = s->priv_data; 108 ByteIOContext *pb = s->pb; 109 int len, fill_size, size1, frame_offset, id; 110 111 size1 = size; 112 while (size > 0) { 113 redo: 114 len = ffm->packet_end - ffm->packet_ptr; 115 if (len < 0) 116 return -1; 117 if (len > size) 118 len = size; 119 if (len == 0) { 120 if (url_ftell(pb) == ffm->file_size) 121 url_fseek(pb, ffm->packet_size, SEEK_SET); 122 retry_read: 123 id = get_be16(pb); /* PACKET_ID */ 124 if (id != PACKET_ID) 125 if (ffm_resync(s, id) < 0) 126 return -1; 127 fill_size = get_be16(pb); 128 ffm->dts = get_be64(pb); 129 frame_offset = get_be16(pb); 130 get_buffer(pb, ffm->packet, ffm->packet_size - FFM_HEADER_SIZE); 131 ffm->packet_end = ffm->packet + (ffm->packet_size - FFM_HEADER_SIZE - fill_size); 132 if (ffm->packet_end < ffm->packet || frame_offset < 0) 133 return -1; 134 /* if first packet or resynchronization packet, we must 135 handle it specifically */ 136 if (ffm->first_packet || (frame_offset & 0x8000)) { 137 if (!frame_offset) { 138 /* This packet has no frame headers in it */ 139 if (url_ftell(pb) >= ffm->packet_size * 3) { 140 url_fseek(pb, -ffm->packet_size * 2, SEEK_CUR); 141 goto retry_read; 142 } 143 /* This is bad, we cannot find a valid frame header */ 144 return 0; 145 } 146 ffm->first_packet = 0; 147 if ((frame_offset & 0x7fff) < FFM_HEADER_SIZE) 148 return -1; 149 ffm->packet_ptr = ffm->packet + (frame_offset & 0x7fff) - FFM_HEADER_SIZE; 150 if (!header) 151 break; 152 } else { 153 ffm->packet_ptr = ffm->packet; 154 } 155 goto redo; 156 } 157 memcpy(buf, ffm->packet_ptr, len); 158 buf += len; 159 ffm->packet_ptr += len; 160 size -= len; 161 header = 0; 162 } 163 return size1 - size; 164} 165 166//#define DEBUG_SEEK 167 168/* ensure that acutal seeking happens between FFM_PACKET_SIZE 169 and file_size - FFM_PACKET_SIZE */ 170static void ffm_seek1(AVFormatContext *s, int64_t pos1) 171{ 172 FFMContext *ffm = s->priv_data; 173 ByteIOContext *pb = s->pb; 174 int64_t pos; 175 176 pos = FFMIN(pos1, ffm->file_size - FFM_PACKET_SIZE); 177 pos = FFMAX(pos, FFM_PACKET_SIZE); 178#ifdef DEBUG_SEEK 179 av_log(s, AV_LOG_DEBUG, "seek to %"PRIx64" -> %"PRIx64"\n", pos1, pos); 180#endif 181 url_fseek(pb, pos, SEEK_SET); 182} 183 184static int64_t get_dts(AVFormatContext *s, int64_t pos) 185{ 186 ByteIOContext *pb = s->pb; 187 int64_t dts; 188 189 ffm_seek1(s, pos); 190 url_fskip(pb, 4); 191 dts = get_be64(pb); 192#ifdef DEBUG_SEEK 193 av_log(s, AV_LOG_DEBUG, "dts=%0.6f\n", dts / 1000000.0); 194#endif 195 return dts; 196} 197 198static void adjust_write_index(AVFormatContext *s) 199{ 200 FFMContext *ffm = s->priv_data; 201 ByteIOContext *pb = s->pb; 202 int64_t pts; 203 //int64_t orig_write_index = ffm->write_index; 204 int64_t pos_min, pos_max; 205 int64_t pts_start; 206 int64_t ptr = url_ftell(pb); 207 208 209 pos_min = 0; 210 pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE; 211 212 pts_start = get_dts(s, pos_min); 213 214 pts = get_dts(s, pos_max); 215 216 if (pts - 100000 > pts_start) 217 goto end; 218 219 ffm->write_index = FFM_PACKET_SIZE; 220 221 pts_start = get_dts(s, pos_min); 222 223 pts = get_dts(s, pos_max); 224 225 if (pts - 100000 <= pts_start) { 226 while (1) { 227 int64_t newpos; 228 int64_t newpts; 229 230 newpos = ((pos_max + pos_min) / (2 * FFM_PACKET_SIZE)) * FFM_PACKET_SIZE; 231 232 if (newpos == pos_min) 233 break; 234 235 newpts = get_dts(s, newpos); 236 237 if (newpts - 100000 <= pts) { 238 pos_max = newpos; 239 pts = newpts; 240 } else { 241 pos_min = newpos; 242 } 243 } 244 ffm->write_index += pos_max; 245 } 246 247 //printf("Adjusted write index from %"PRId64" to %"PRId64": pts=%0.6f\n", orig_write_index, ffm->write_index, pts / 1000000.); 248 //printf("pts range %0.6f - %0.6f\n", get_dts(s, 0) / 1000000. , get_dts(s, ffm->file_size - 2 * FFM_PACKET_SIZE) / 1000000. ); 249 250 end: 251 url_fseek(pb, ptr, SEEK_SET); 252} 253 254 255static int ffm_read_header(AVFormatContext *s, AVFormatParameters *ap) 256{ 257 FFMContext *ffm = s->priv_data; 258 AVStream *st; 259 ByteIOContext *pb = s->pb; 260 AVCodecContext *codec; 261 int i, nb_streams; 262 uint32_t tag; 263 264 /* header */ 265 tag = get_le32(pb); 266 if (tag != MKTAG('F', 'F', 'M', '1')) 267 goto fail; 268 ffm->packet_size = get_be32(pb); 269 if (ffm->packet_size != FFM_PACKET_SIZE) 270 goto fail; 271 ffm->write_index = get_be64(pb); 272 /* get also filesize */ 273 if (!url_is_streamed(pb)) { 274 ffm->file_size = url_fsize(pb); 275 if (ffm->write_index) 276 adjust_write_index(s); 277 } else { 278 ffm->file_size = (UINT64_C(1) << 63) - 1; 279 } 280 281 nb_streams = get_be32(pb); 282 get_be32(pb); /* total bitrate */ 283 /* read each stream */ 284 for(i=0;i<nb_streams;i++) { 285 char rc_eq_buf[128]; 286 287 st = av_new_stream(s, 0); 288 if (!st) 289 goto fail; 290 291 av_set_pts_info(st, 64, 1, 1000000); 292 293 codec = st->codec; 294 /* generic info */ 295 codec->codec_id = get_be32(pb); 296 codec->codec_type = get_byte(pb); /* codec_type */ 297 codec->bit_rate = get_be32(pb); 298 st->quality = get_be32(pb); 299 codec->flags = get_be32(pb); 300 codec->flags2 = get_be32(pb); 301 codec->debug = get_be32(pb); 302 /* specific info */ 303 switch(codec->codec_type) { 304 case AVMEDIA_TYPE_VIDEO: 305 codec->time_base.num = get_be32(pb); 306 codec->time_base.den = get_be32(pb); 307 codec->width = get_be16(pb); 308 codec->height = get_be16(pb); 309 codec->gop_size = get_be16(pb); 310 codec->pix_fmt = get_be32(pb); 311 codec->qmin = get_byte(pb); 312 codec->qmax = get_byte(pb); 313 codec->max_qdiff = get_byte(pb); 314 codec->qcompress = get_be16(pb) / 10000.0; 315 codec->qblur = get_be16(pb) / 10000.0; 316 codec->bit_rate_tolerance = get_be32(pb); 317 codec->rc_eq = av_strdup(get_strz(pb, rc_eq_buf, sizeof(rc_eq_buf))); 318 codec->rc_max_rate = get_be32(pb); 319 codec->rc_min_rate = get_be32(pb); 320 codec->rc_buffer_size = get_be32(pb); 321 codec->i_quant_factor = av_int2dbl(get_be64(pb)); 322 codec->b_quant_factor = av_int2dbl(get_be64(pb)); 323 codec->i_quant_offset = av_int2dbl(get_be64(pb)); 324 codec->b_quant_offset = av_int2dbl(get_be64(pb)); 325 codec->dct_algo = get_be32(pb); 326 codec->strict_std_compliance = get_be32(pb); 327 codec->max_b_frames = get_be32(pb); 328 codec->luma_elim_threshold = get_be32(pb); 329 codec->chroma_elim_threshold = get_be32(pb); 330 codec->mpeg_quant = get_be32(pb); 331 codec->intra_dc_precision = get_be32(pb); 332 codec->me_method = get_be32(pb); 333 codec->mb_decision = get_be32(pb); 334 codec->nsse_weight = get_be32(pb); 335 codec->frame_skip_cmp = get_be32(pb); 336 codec->rc_buffer_aggressivity = av_int2dbl(get_be64(pb)); 337 codec->codec_tag = get_be32(pb); 338 codec->thread_count = get_byte(pb); 339 codec->coder_type = get_be32(pb); 340 codec->me_cmp = get_be32(pb); 341 codec->partitions = get_be32(pb); 342 codec->me_subpel_quality = get_be32(pb); 343 codec->me_range = get_be32(pb); 344 codec->keyint_min = get_be32(pb); 345 codec->scenechange_threshold = get_be32(pb); 346 codec->b_frame_strategy = get_be32(pb); 347 codec->qcompress = av_int2dbl(get_be64(pb)); 348 codec->qblur = av_int2dbl(get_be64(pb)); 349 codec->max_qdiff = get_be32(pb); 350 codec->refs = get_be32(pb); 351 codec->directpred = get_be32(pb); 352 break; 353 case AVMEDIA_TYPE_AUDIO: 354 codec->sample_rate = get_be32(pb); 355 codec->channels = get_le16(pb); 356 codec->frame_size = get_le16(pb); 357 codec->sample_fmt = (int16_t) get_le16(pb); 358 break; 359 default: 360 goto fail; 361 } 362 if (codec->flags & CODEC_FLAG_GLOBAL_HEADER) { 363 codec->extradata_size = get_be32(pb); 364 codec->extradata = av_malloc(codec->extradata_size); 365 if (!codec->extradata) 366 return AVERROR(ENOMEM); 367 get_buffer(pb, codec->extradata, codec->extradata_size); 368 } 369 } 370 371 /* get until end of block reached */ 372 while ((url_ftell(pb) % ffm->packet_size) != 0) 373 get_byte(pb); 374 375 /* init packet demux */ 376 ffm->packet_ptr = ffm->packet; 377 ffm->packet_end = ffm->packet; 378 ffm->frame_offset = 0; 379 ffm->dts = 0; 380 ffm->read_state = READ_HEADER; 381 ffm->first_packet = 1; 382 return 0; 383 fail: 384 for(i=0;i<s->nb_streams;i++) { 385 st = s->streams[i]; 386 if (st) { 387 av_free(st); 388 } 389 } 390 return -1; 391} 392 393/* return < 0 if eof */ 394static int ffm_read_packet(AVFormatContext *s, AVPacket *pkt) 395{ 396 int size; 397 FFMContext *ffm = s->priv_data; 398 int duration, ret; 399 400 switch(ffm->read_state) { 401 case READ_HEADER: 402 if ((ret = ffm_is_avail_data(s, FRAME_HEADER_SIZE+4)) < 0) 403 return ret; 404 405 dprintf(s, "pos=%08"PRIx64" spos=%"PRIx64", write_index=%"PRIx64" size=%"PRIx64"\n", 406 url_ftell(s->pb), s->pb->pos, ffm->write_index, ffm->file_size); 407 if (ffm_read_data(s, ffm->header, FRAME_HEADER_SIZE, 1) != 408 FRAME_HEADER_SIZE) 409 return -1; 410 if (ffm->header[1] & FLAG_DTS) 411 if (ffm_read_data(s, ffm->header+16, 4, 1) != 4) 412 return -1; 413#if 0 414 av_hexdump_log(s, AV_LOG_DEBUG, ffm->header, FRAME_HEADER_SIZE); 415#endif 416 ffm->read_state = READ_DATA; 417 /* fall thru */ 418 case READ_DATA: 419 size = AV_RB24(ffm->header + 2); 420 if ((ret = ffm_is_avail_data(s, size)) < 0) 421 return ret; 422 423 duration = AV_RB24(ffm->header + 5); 424 425 av_new_packet(pkt, size); 426 pkt->stream_index = ffm->header[0]; 427 if ((unsigned)pkt->stream_index >= s->nb_streams) { 428 av_log(s, AV_LOG_ERROR, "invalid stream index %d\n", pkt->stream_index); 429 av_free_packet(pkt); 430 ffm->read_state = READ_HEADER; 431 return -1; 432 } 433 pkt->pos = url_ftell(s->pb); 434 if (ffm->header[1] & FLAG_KEY_FRAME) 435 pkt->flags |= AV_PKT_FLAG_KEY; 436 437 ffm->read_state = READ_HEADER; 438 if (ffm_read_data(s, pkt->data, size, 0) != size) { 439 /* bad case: desynchronized packet. we cancel all the packet loading */ 440 av_free_packet(pkt); 441 return -1; 442 } 443 pkt->pts = AV_RB64(ffm->header+8); 444 if (ffm->header[1] & FLAG_DTS) 445 pkt->dts = pkt->pts - AV_RB32(ffm->header+16); 446 else 447 pkt->dts = pkt->pts; 448 pkt->duration = duration; 449 break; 450 } 451 return 0; 452} 453 454/* seek to a given time in the file. The file read pointer is 455 positioned at or before pts. XXX: the following code is quite 456 approximative */ 457static int ffm_seek(AVFormatContext *s, int stream_index, int64_t wanted_pts, int flags) 458{ 459 FFMContext *ffm = s->priv_data; 460 int64_t pos_min, pos_max, pos; 461 int64_t pts_min, pts_max, pts; 462 double pos1; 463 464#ifdef DEBUG_SEEK 465 av_log(s, AV_LOG_DEBUG, "wanted_pts=%0.6f\n", wanted_pts / 1000000.0); 466#endif 467 /* find the position using linear interpolation (better than 468 dichotomy in typical cases) */ 469 pos_min = FFM_PACKET_SIZE; 470 pos_max = ffm->file_size - FFM_PACKET_SIZE; 471 while (pos_min <= pos_max) { 472 pts_min = get_dts(s, pos_min); 473 pts_max = get_dts(s, pos_max); 474 /* linear interpolation */ 475 pos1 = (double)(pos_max - pos_min) * (double)(wanted_pts - pts_min) / 476 (double)(pts_max - pts_min); 477 pos = (((int64_t)pos1) / FFM_PACKET_SIZE) * FFM_PACKET_SIZE; 478 if (pos <= pos_min) 479 pos = pos_min; 480 else if (pos >= pos_max) 481 pos = pos_max; 482 pts = get_dts(s, pos); 483 /* check if we are lucky */ 484 if (pts == wanted_pts) { 485 goto found; 486 } else if (pts > wanted_pts) { 487 pos_max = pos - FFM_PACKET_SIZE; 488 } else { 489 pos_min = pos + FFM_PACKET_SIZE; 490 } 491 } 492 pos = (flags & AVSEEK_FLAG_BACKWARD) ? pos_min : pos_max; 493 494 found: 495 ffm_seek1(s, pos); 496 497 /* reset read state */ 498 ffm->read_state = READ_HEADER; 499 ffm->packet_ptr = ffm->packet; 500 ffm->packet_end = ffm->packet; 501 ffm->first_packet = 1; 502 503 return 0; 504} 505 506static int ffm_probe(AVProbeData *p) 507{ 508 if ( 509 p->buf[0] == 'F' && p->buf[1] == 'F' && p->buf[2] == 'M' && 510 p->buf[3] == '1') 511 return AVPROBE_SCORE_MAX + 1; 512 return 0; 513} 514 515static int ffm_close(AVFormatContext *s) 516{ 517 int i; 518 519 for (i = 0; i < s->nb_streams; i++) 520 av_freep(&s->streams[i]->codec->rc_eq); 521 522 return 0; 523} 524 525AVInputFormat ffm_demuxer = { 526 "ffm", 527 NULL_IF_CONFIG_SMALL("FFM (FFserver live feed) format"), 528 sizeof(FFMContext), 529 ffm_probe, 530 ffm_read_header, 531 ffm_read_packet, 532 ffm_close, 533 ffm_seek, 534}; 535