1/* 2 * FFM (avserver live feed) demuxer 3 * Copyright (c) 2001 Fabrice Bellard 4 * 5 * This file is part of Libav. 6 * 7 * Libav 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 * Libav 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 Libav; 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 "libavutil/intfloat.h" 24#include "avformat.h" 25#include "internal.h" 26#include "ffm.h" 27#if CONFIG_AVSERVER 28#include <unistd.h> 29 30int64_t ffm_read_write_index(int fd) 31{ 32 uint8_t buf[8]; 33 34 lseek(fd, 8, SEEK_SET); 35 if (read(fd, buf, 8) != 8) 36 return AVERROR(EIO); 37 return AV_RB64(buf); 38} 39 40int ffm_write_write_index(int fd, int64_t pos) 41{ 42 uint8_t buf[8]; 43 int i; 44 45 for(i=0;i<8;i++) 46 buf[i] = (pos >> (56 - i * 8)) & 0xff; 47 lseek(fd, 8, SEEK_SET); 48 if (write(fd, buf, 8) != 8) 49 return AVERROR(EIO); 50 return 8; 51} 52 53void ffm_set_write_index(AVFormatContext *s, int64_t pos, int64_t file_size) 54{ 55 FFMContext *ffm = s->priv_data; 56 ffm->write_index = pos; 57 ffm->file_size = file_size; 58} 59#endif // CONFIG_AVSERVER 60 61static int ffm_is_avail_data(AVFormatContext *s, int size) 62{ 63 FFMContext *ffm = s->priv_data; 64 int64_t pos, avail_size; 65 int len; 66 67 len = ffm->packet_end - ffm->packet_ptr; 68 if (size <= len) 69 return 1; 70 pos = avio_tell(s->pb); 71 if (!ffm->write_index) { 72 if (pos == ffm->file_size) 73 return AVERROR_EOF; 74 avail_size = ffm->file_size - pos; 75 } else { 76 if (pos == ffm->write_index) { 77 /* exactly at the end of stream */ 78 return AVERROR(EAGAIN); 79 } else if (pos < ffm->write_index) { 80 avail_size = ffm->write_index - pos; 81 } else { 82 avail_size = (ffm->file_size - pos) + (ffm->write_index - FFM_PACKET_SIZE); 83 } 84 } 85 avail_size = (avail_size / ffm->packet_size) * (ffm->packet_size - FFM_HEADER_SIZE) + len; 86 if (size <= avail_size) 87 return 1; 88 else 89 return AVERROR(EAGAIN); 90} 91 92static int ffm_resync(AVFormatContext *s, int state) 93{ 94 av_log(s, AV_LOG_ERROR, "resyncing\n"); 95 while (state != PACKET_ID) { 96 if (s->pb->eof_reached) { 97 av_log(s, AV_LOG_ERROR, "cannot find FFM syncword\n"); 98 return -1; 99 } 100 state = (state << 8) | avio_r8(s->pb); 101 } 102 return 0; 103} 104 105/* first is true if we read the frame header */ 106static int ffm_read_data(AVFormatContext *s, 107 uint8_t *buf, int size, int header) 108{ 109 FFMContext *ffm = s->priv_data; 110 AVIOContext *pb = s->pb; 111 int len, fill_size, size1, frame_offset, id; 112 113 size1 = size; 114 while (size > 0) { 115 redo: 116 len = ffm->packet_end - ffm->packet_ptr; 117 if (len < 0) 118 return -1; 119 if (len > size) 120 len = size; 121 if (len == 0) { 122 if (avio_tell(pb) == ffm->file_size) 123 avio_seek(pb, ffm->packet_size, SEEK_SET); 124 retry_read: 125 id = avio_rb16(pb); /* PACKET_ID */ 126 if (id != PACKET_ID) 127 if (ffm_resync(s, id) < 0) 128 return -1; 129 fill_size = avio_rb16(pb); 130 ffm->dts = avio_rb64(pb); 131 frame_offset = avio_rb16(pb); 132 avio_read(pb, ffm->packet, ffm->packet_size - FFM_HEADER_SIZE); 133 ffm->packet_end = ffm->packet + (ffm->packet_size - FFM_HEADER_SIZE - fill_size); 134 if (ffm->packet_end < ffm->packet || frame_offset < 0) 135 return -1; 136 /* if first packet or resynchronization packet, we must 137 handle it specifically */ 138 if (ffm->first_packet || (frame_offset & 0x8000)) { 139 if (!frame_offset) { 140 /* This packet has no frame headers in it */ 141 if (avio_tell(pb) >= ffm->packet_size * 3) { 142 avio_seek(pb, -ffm->packet_size * 2, SEEK_CUR); 143 goto retry_read; 144 } 145 /* This is bad, we cannot find a valid frame header */ 146 return 0; 147 } 148 ffm->first_packet = 0; 149 if ((frame_offset & 0x7fff) < FFM_HEADER_SIZE) 150 return -1; 151 ffm->packet_ptr = ffm->packet + (frame_offset & 0x7fff) - FFM_HEADER_SIZE; 152 if (!header) 153 break; 154 } else { 155 ffm->packet_ptr = ffm->packet; 156 } 157 goto redo; 158 } 159 memcpy(buf, ffm->packet_ptr, len); 160 buf += len; 161 ffm->packet_ptr += len; 162 size -= len; 163 header = 0; 164 } 165 return size1 - size; 166} 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 AVIOContext *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 av_dlog(s, "seek to %"PRIx64" -> %"PRIx64"\n", pos1, pos); 179 avio_seek(pb, pos, SEEK_SET); 180} 181 182static int64_t get_dts(AVFormatContext *s, int64_t pos) 183{ 184 AVIOContext *pb = s->pb; 185 int64_t dts; 186 187 ffm_seek1(s, pos); 188 avio_skip(pb, 4); 189 dts = avio_rb64(pb); 190 av_dlog(s, "dts=%0.6f\n", dts / 1000000.0); 191 return dts; 192} 193 194static void adjust_write_index(AVFormatContext *s) 195{ 196 FFMContext *ffm = s->priv_data; 197 AVIOContext *pb = s->pb; 198 int64_t pts; 199 //int64_t orig_write_index = ffm->write_index; 200 int64_t pos_min, pos_max; 201 int64_t pts_start; 202 int64_t ptr = avio_tell(pb); 203 204 205 pos_min = 0; 206 pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE; 207 208 pts_start = get_dts(s, pos_min); 209 210 pts = get_dts(s, pos_max); 211 212 if (pts - 100000 > pts_start) 213 goto end; 214 215 ffm->write_index = FFM_PACKET_SIZE; 216 217 pts_start = get_dts(s, pos_min); 218 219 pts = get_dts(s, pos_max); 220 221 if (pts - 100000 <= pts_start) { 222 while (1) { 223 int64_t newpos; 224 int64_t newpts; 225 226 newpos = ((pos_max + pos_min) / (2 * FFM_PACKET_SIZE)) * FFM_PACKET_SIZE; 227 228 if (newpos == pos_min) 229 break; 230 231 newpts = get_dts(s, newpos); 232 233 if (newpts - 100000 <= pts) { 234 pos_max = newpos; 235 pts = newpts; 236 } else { 237 pos_min = newpos; 238 } 239 } 240 ffm->write_index += pos_max; 241 } 242 243 //printf("Adjusted write index from %"PRId64" to %"PRId64": pts=%0.6f\n", orig_write_index, ffm->write_index, pts / 1000000.); 244 //printf("pts range %0.6f - %0.6f\n", get_dts(s, 0) / 1000000. , get_dts(s, ffm->file_size - 2 * FFM_PACKET_SIZE) / 1000000. ); 245 246 end: 247 avio_seek(pb, ptr, SEEK_SET); 248} 249 250 251static int ffm_close(AVFormatContext *s) 252{ 253 int i; 254 255 for (i = 0; i < s->nb_streams; i++) 256 av_freep(&s->streams[i]->codec->rc_eq); 257 258 return 0; 259} 260 261 262static int ffm_read_header(AVFormatContext *s, AVFormatParameters *ap) 263{ 264 FFMContext *ffm = s->priv_data; 265 AVStream *st; 266 AVIOContext *pb = s->pb; 267 AVCodecContext *codec; 268 int i, nb_streams; 269 uint32_t tag; 270 271 /* header */ 272 tag = avio_rl32(pb); 273 if (tag != MKTAG('F', 'F', 'M', '1')) 274 goto fail; 275 ffm->packet_size = avio_rb32(pb); 276 if (ffm->packet_size != FFM_PACKET_SIZE) 277 goto fail; 278 ffm->write_index = avio_rb64(pb); 279 /* get also filesize */ 280 if (pb->seekable) { 281 ffm->file_size = avio_size(pb); 282 if (ffm->write_index) 283 adjust_write_index(s); 284 } else { 285 ffm->file_size = (UINT64_C(1) << 63) - 1; 286 } 287 288 nb_streams = avio_rb32(pb); 289 avio_rb32(pb); /* total bitrate */ 290 /* read each stream */ 291 for(i=0;i<nb_streams;i++) { 292 char rc_eq_buf[128]; 293 294 st = avformat_new_stream(s, NULL); 295 if (!st) 296 goto fail; 297 298 avpriv_set_pts_info(st, 64, 1, 1000000); 299 300 codec = st->codec; 301 /* generic info */ 302 codec->codec_id = avio_rb32(pb); 303 codec->codec_type = avio_r8(pb); /* codec_type */ 304 codec->bit_rate = avio_rb32(pb); 305 codec->flags = avio_rb32(pb); 306 codec->flags2 = avio_rb32(pb); 307 codec->debug = avio_rb32(pb); 308 /* specific info */ 309 switch(codec->codec_type) { 310 case AVMEDIA_TYPE_VIDEO: 311 codec->time_base.num = avio_rb32(pb); 312 codec->time_base.den = avio_rb32(pb); 313 codec->width = avio_rb16(pb); 314 codec->height = avio_rb16(pb); 315 codec->gop_size = avio_rb16(pb); 316 codec->pix_fmt = avio_rb32(pb); 317 codec->qmin = avio_r8(pb); 318 codec->qmax = avio_r8(pb); 319 codec->max_qdiff = avio_r8(pb); 320 codec->qcompress = avio_rb16(pb) / 10000.0; 321 codec->qblur = avio_rb16(pb) / 10000.0; 322 codec->bit_rate_tolerance = avio_rb32(pb); 323 avio_get_str(pb, INT_MAX, rc_eq_buf, sizeof(rc_eq_buf)); 324 codec->rc_eq = av_strdup(rc_eq_buf); 325 codec->rc_max_rate = avio_rb32(pb); 326 codec->rc_min_rate = avio_rb32(pb); 327 codec->rc_buffer_size = avio_rb32(pb); 328 codec->i_quant_factor = av_int2double(avio_rb64(pb)); 329 codec->b_quant_factor = av_int2double(avio_rb64(pb)); 330 codec->i_quant_offset = av_int2double(avio_rb64(pb)); 331 codec->b_quant_offset = av_int2double(avio_rb64(pb)); 332 codec->dct_algo = avio_rb32(pb); 333 codec->strict_std_compliance = avio_rb32(pb); 334 codec->max_b_frames = avio_rb32(pb); 335 codec->luma_elim_threshold = avio_rb32(pb); 336 codec->chroma_elim_threshold = avio_rb32(pb); 337 codec->mpeg_quant = avio_rb32(pb); 338 codec->intra_dc_precision = avio_rb32(pb); 339 codec->me_method = avio_rb32(pb); 340 codec->mb_decision = avio_rb32(pb); 341 codec->nsse_weight = avio_rb32(pb); 342 codec->frame_skip_cmp = avio_rb32(pb); 343 codec->rc_buffer_aggressivity = av_int2double(avio_rb64(pb)); 344 codec->codec_tag = avio_rb32(pb); 345 codec->thread_count = avio_r8(pb); 346 codec->coder_type = avio_rb32(pb); 347 codec->me_cmp = avio_rb32(pb); 348 codec->me_subpel_quality = avio_rb32(pb); 349 codec->me_range = avio_rb32(pb); 350 codec->keyint_min = avio_rb32(pb); 351 codec->scenechange_threshold = avio_rb32(pb); 352 codec->b_frame_strategy = avio_rb32(pb); 353 codec->qcompress = av_int2double(avio_rb64(pb)); 354 codec->qblur = av_int2double(avio_rb64(pb)); 355 codec->max_qdiff = avio_rb32(pb); 356 codec->refs = avio_rb32(pb); 357 break; 358 case AVMEDIA_TYPE_AUDIO: 359 codec->sample_rate = avio_rb32(pb); 360 codec->channels = avio_rl16(pb); 361 codec->frame_size = avio_rl16(pb); 362 codec->sample_fmt = (int16_t) avio_rl16(pb); 363 break; 364 default: 365 goto fail; 366 } 367 if (codec->flags & CODEC_FLAG_GLOBAL_HEADER) { 368 codec->extradata_size = avio_rb32(pb); 369 codec->extradata = av_malloc(codec->extradata_size); 370 if (!codec->extradata) 371 return AVERROR(ENOMEM); 372 avio_read(pb, codec->extradata, codec->extradata_size); 373 } 374 } 375 376 /* get until end of block reached */ 377 while ((avio_tell(pb) % ffm->packet_size) != 0) 378 avio_r8(pb); 379 380 /* init packet demux */ 381 ffm->packet_ptr = ffm->packet; 382 ffm->packet_end = ffm->packet; 383 ffm->frame_offset = 0; 384 ffm->dts = 0; 385 ffm->read_state = READ_HEADER; 386 ffm->first_packet = 1; 387 return 0; 388 fail: 389 ffm_close(s); 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 av_dlog(s, "pos=%08"PRIx64" spos=%"PRIx64", write_index=%"PRIx64" size=%"PRIx64"\n", 406 avio_tell(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 ffm->read_state = READ_DATA; 414 /* fall thru */ 415 case READ_DATA: 416 size = AV_RB24(ffm->header + 2); 417 if ((ret = ffm_is_avail_data(s, size)) < 0) 418 return ret; 419 420 duration = AV_RB24(ffm->header + 5); 421 422 av_new_packet(pkt, size); 423 pkt->stream_index = ffm->header[0]; 424 if ((unsigned)pkt->stream_index >= s->nb_streams) { 425 av_log(s, AV_LOG_ERROR, "invalid stream index %d\n", pkt->stream_index); 426 av_free_packet(pkt); 427 ffm->read_state = READ_HEADER; 428 return -1; 429 } 430 pkt->pos = avio_tell(s->pb); 431 if (ffm->header[1] & FLAG_KEY_FRAME) 432 pkt->flags |= AV_PKT_FLAG_KEY; 433 434 ffm->read_state = READ_HEADER; 435 if (ffm_read_data(s, pkt->data, size, 0) != size) { 436 /* bad case: desynchronized packet. we cancel all the packet loading */ 437 av_free_packet(pkt); 438 return -1; 439 } 440 pkt->pts = AV_RB64(ffm->header+8); 441 if (ffm->header[1] & FLAG_DTS) 442 pkt->dts = pkt->pts - AV_RB32(ffm->header+16); 443 else 444 pkt->dts = pkt->pts; 445 pkt->duration = duration; 446 break; 447 } 448 return 0; 449} 450 451/* seek to a given time in the file. The file read pointer is 452 positioned at or before pts. XXX: the following code is quite 453 approximative */ 454static int ffm_seek(AVFormatContext *s, int stream_index, int64_t wanted_pts, int flags) 455{ 456 FFMContext *ffm = s->priv_data; 457 int64_t pos_min, pos_max, pos; 458 int64_t pts_min, pts_max, pts; 459 double pos1; 460 461 av_dlog(s, "wanted_pts=%0.6f\n", wanted_pts / 1000000.0); 462 /* find the position using linear interpolation (better than 463 dichotomy in typical cases) */ 464 pos_min = FFM_PACKET_SIZE; 465 pos_max = ffm->file_size - FFM_PACKET_SIZE; 466 while (pos_min <= pos_max) { 467 pts_min = get_dts(s, pos_min); 468 pts_max = get_dts(s, pos_max); 469 /* linear interpolation */ 470 pos1 = (double)(pos_max - pos_min) * (double)(wanted_pts - pts_min) / 471 (double)(pts_max - pts_min); 472 pos = (((int64_t)pos1) / FFM_PACKET_SIZE) * FFM_PACKET_SIZE; 473 if (pos <= pos_min) 474 pos = pos_min; 475 else if (pos >= pos_max) 476 pos = pos_max; 477 pts = get_dts(s, pos); 478 /* check if we are lucky */ 479 if (pts == wanted_pts) { 480 goto found; 481 } else if (pts > wanted_pts) { 482 pos_max = pos - FFM_PACKET_SIZE; 483 } else { 484 pos_min = pos + FFM_PACKET_SIZE; 485 } 486 } 487 pos = (flags & AVSEEK_FLAG_BACKWARD) ? pos_min : pos_max; 488 489 found: 490 ffm_seek1(s, pos); 491 492 /* reset read state */ 493 ffm->read_state = READ_HEADER; 494 ffm->packet_ptr = ffm->packet; 495 ffm->packet_end = ffm->packet; 496 ffm->first_packet = 1; 497 498 return 0; 499} 500 501static int ffm_probe(AVProbeData *p) 502{ 503 if ( 504 p->buf[0] == 'F' && p->buf[1] == 'F' && p->buf[2] == 'M' && 505 p->buf[3] == '1') 506 return AVPROBE_SCORE_MAX + 1; 507 return 0; 508} 509 510AVInputFormat ff_ffm_demuxer = { 511 .name = "ffm", 512 .long_name = NULL_IF_CONFIG_SMALL("FFM (AVserver live feed) format"), 513 .priv_data_size = sizeof(FFMContext), 514 .read_probe = ffm_probe, 515 .read_header = ffm_read_header, 516 .read_packet = ffm_read_packet, 517 .read_close = ffm_close, 518 .read_seek = ffm_seek, 519}; 520