/* * FFM (ffserver live feed) demuxer * Copyright (c) 2001 Fabrice Bellard. * * 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 "ffm.h" #ifdef CONFIG_FFSERVER #include <unistd.h> offset_t ffm_read_write_index(int fd) { uint8_t buf[8]; lseek(fd, 8, SEEK_SET); read(fd, buf, 8); return AV_RB64(buf); } void ffm_write_write_index(int fd, offset_t pos) { uint8_t buf[8]; int i; for(i=0;i<8;i++) buf[i] = (pos >> (56 - i * 8)) & 0xff; lseek(fd, 8, SEEK_SET); write(fd, buf, 8); } void ffm_set_write_index(AVFormatContext *s, offset_t pos, offset_t file_size) { FFMContext *ffm = s->priv_data; ffm->write_index = pos; ffm->file_size = file_size; } #endif // CONFIG_FFSERVER static int ffm_is_avail_data(AVFormatContext *s, int size) { FFMContext *ffm = s->priv_data; offset_t pos, avail_size; int len; len = ffm->packet_end - ffm->packet_ptr; if (size <= len) return 1; pos = url_ftell(s->pb); if (pos == ffm->write_index) { /* exactly at the end of stream */ return 0; } else if (pos < ffm->write_index) { avail_size = ffm->write_index - pos; } else { avail_size = (ffm->file_size - pos) + (ffm->write_index - FFM_PACKET_SIZE); } avail_size = (avail_size / ffm->packet_size) * (ffm->packet_size - FFM_HEADER_SIZE) + len; if (size <= avail_size) return 1; else return 0; } /* first is true if we read the frame header */ static int ffm_read_data(AVFormatContext *s, uint8_t *buf, int size, int first) { FFMContext *ffm = s->priv_data; ByteIOContext *pb = s->pb; int len, fill_size, size1, frame_offset; size1 = size; while (size > 0) { redo: len = ffm->packet_end - ffm->packet_ptr; if (len < 0) return -1; if (len > size) len = size; if (len == 0) { if (url_ftell(pb) == ffm->file_size) url_fseek(pb, ffm->packet_size, SEEK_SET); retry_read: get_be16(pb); /* PACKET_ID */ fill_size = get_be16(pb); ffm->pts = get_be64(pb); ffm->first_frame_in_packet = 1; frame_offset = get_be16(pb); get_buffer(pb, ffm->packet, ffm->packet_size - FFM_HEADER_SIZE); ffm->packet_end = ffm->packet + (ffm->packet_size - FFM_HEADER_SIZE - fill_size); if (ffm->packet_end < ffm->packet || frame_offset < 0) return -1; /* if first packet or resynchronization packet, we must handle it specifically */ if (ffm->first_packet || (frame_offset & 0x8000)) { if (!frame_offset) { /* This packet has no frame headers in it */ if (url_ftell(pb) >= ffm->packet_size * 3) { url_fseek(pb, -ffm->packet_size * 2, SEEK_CUR); goto retry_read; } /* This is bad, we cannot find a valid frame header */ return 0; } ffm->first_packet = 0; if ((frame_offset & 0x7fff) < FFM_HEADER_SIZE) return -1; ffm->packet_ptr = ffm->packet + (frame_offset & 0x7fff) - FFM_HEADER_SIZE; if (!first) break; } else { ffm->packet_ptr = ffm->packet; } goto redo; } memcpy(buf, ffm->packet_ptr, len); buf += len; ffm->packet_ptr += len; size -= len; first = 0; } return size1 - size; } //#define DEBUG_SEEK /* pos is between 0 and file_size - FFM_PACKET_SIZE. It is translated by the write position inside this function */ static void ffm_seek1(AVFormatContext *s, offset_t pos1) { FFMContext *ffm = s->priv_data; ByteIOContext *pb = s->pb; offset_t pos; pos = pos1 + ffm->write_index; if (pos >= ffm->file_size) pos -= (ffm->file_size - FFM_PACKET_SIZE); #ifdef DEBUG_SEEK av_log(s, AV_LOG_DEBUG, "seek to %"PRIx64" -> %"PRIx64"\n", pos1, pos); #endif url_fseek(pb, pos, SEEK_SET); } static int64_t get_pts(AVFormatContext *s, offset_t pos) { ByteIOContext *pb = s->pb; int64_t pts; ffm_seek1(s, pos); url_fskip(pb, 4); pts = get_be64(pb); #ifdef DEBUG_SEEK av_log(s, AV_LOG_DEBUG, "pts=%0.6f\n", pts / 1000000.0); #endif return pts; } static void adjust_write_index(AVFormatContext *s) { FFMContext *ffm = s->priv_data; ByteIOContext *pb = s->pb; int64_t pts; //offset_t orig_write_index = ffm->write_index; offset_t pos_min, pos_max; int64_t pts_start; offset_t ptr = url_ftell(pb); pos_min = 0; pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE; pts_start = get_pts(s, pos_min); pts = get_pts(s, pos_max); if (pts - 100000 > pts_start) goto end; ffm->write_index = FFM_PACKET_SIZE; pts_start = get_pts(s, pos_min); pts = get_pts(s, pos_max); if (pts - 100000 <= pts_start) { while (1) { offset_t newpos; int64_t newpts; newpos = ((pos_max + pos_min) / (2 * FFM_PACKET_SIZE)) * FFM_PACKET_SIZE; if (newpos == pos_min) break; newpts = get_pts(s, newpos); if (newpts - 100000 <= pts) { pos_max = newpos; pts = newpts; } else { pos_min = newpos; } } ffm->write_index += pos_max; } //printf("Adjusted write index from %"PRId64" to %"PRId64": pts=%0.6f\n", orig_write_index, ffm->write_index, pts / 1000000.); //printf("pts range %0.6f - %0.6f\n", get_pts(s, 0) / 1000000. , get_pts(s, ffm->file_size - 2 * FFM_PACKET_SIZE) / 1000000. ); end: url_fseek(pb, ptr, SEEK_SET); } static int ffm_read_header(AVFormatContext *s, AVFormatParameters *ap) { FFMContext *ffm = s->priv_data; AVStream *st; FFMStream *fst; ByteIOContext *pb = s->pb; AVCodecContext *codec; int i, nb_streams; uint32_t tag; /* header */ tag = get_le32(pb); if (tag != MKTAG('F', 'F', 'M', '1')) goto fail; ffm->packet_size = get_be32(pb); if (ffm->packet_size != FFM_PACKET_SIZE) goto fail; ffm->write_index = get_be64(pb); /* get also filesize */ if (!url_is_streamed(pb)) { ffm->file_size = url_fsize(pb); adjust_write_index(s); } else { ffm->file_size = (UINT64_C(1) << 63) - 1; } nb_streams = get_be32(pb); get_be32(pb); /* total bitrate */ /* read each stream */ for(i=0;i<nb_streams;i++) { char rc_eq_buf[128]; st = av_new_stream(s, 0); if (!st) goto fail; fst = av_mallocz(sizeof(FFMStream)); if (!fst) goto fail; s->streams[i] = st; av_set_pts_info(st, 64, 1, 1000000); st->priv_data = fst; codec = st->codec; /* generic info */ codec->codec_id = get_be32(pb); codec->codec_type = get_byte(pb); /* codec_type */ codec->bit_rate = get_be32(pb); st->quality = get_be32(pb); codec->flags = get_be32(pb); codec->flags2 = get_be32(pb); codec->debug = get_be32(pb); /* specific info */ switch(codec->codec_type) { case CODEC_TYPE_VIDEO: codec->time_base.num = get_be32(pb); codec->time_base.den = get_be32(pb); codec->width = get_be16(pb); codec->height = get_be16(pb); codec->gop_size = get_be16(pb); codec->pix_fmt = get_be32(pb); codec->qmin = get_byte(pb); codec->qmax = get_byte(pb); codec->max_qdiff = get_byte(pb); codec->qcompress = get_be16(pb) / 10000.0; codec->qblur = get_be16(pb) / 10000.0; codec->bit_rate_tolerance = get_be32(pb); codec->rc_eq = av_strdup(get_strz(pb, rc_eq_buf, sizeof(rc_eq_buf))); codec->rc_max_rate = get_be32(pb); codec->rc_min_rate = get_be32(pb); codec->rc_buffer_size = get_be32(pb); codec->i_quant_factor = av_int2dbl(get_be64(pb)); codec->b_quant_factor = av_int2dbl(get_be64(pb)); codec->i_quant_offset = av_int2dbl(get_be64(pb)); codec->b_quant_offset = av_int2dbl(get_be64(pb)); codec->dct_algo = get_be32(pb); codec->strict_std_compliance = get_be32(pb); codec->max_b_frames = get_be32(pb); codec->luma_elim_threshold = get_be32(pb); codec->chroma_elim_threshold = get_be32(pb); codec->mpeg_quant = get_be32(pb); codec->intra_dc_precision = get_be32(pb); codec->me_method = get_be32(pb); codec->mb_decision = get_be32(pb); codec->nsse_weight = get_be32(pb); codec->frame_skip_cmp = get_be32(pb); codec->rc_buffer_aggressivity = av_int2dbl(get_be64(pb)); codec->codec_tag = get_be32(pb); break; case CODEC_TYPE_AUDIO: codec->sample_rate = get_be32(pb); codec->channels = get_le16(pb); codec->frame_size = get_le16(pb); break; default: goto fail; } } /* get until end of block reached */ while ((url_ftell(pb) % ffm->packet_size) != 0) get_byte(pb); /* init packet demux */ ffm->packet_ptr = ffm->packet; ffm->packet_end = ffm->packet; ffm->frame_offset = 0; ffm->pts = 0; ffm->read_state = READ_HEADER; ffm->first_packet = 1; return 0; fail: for(i=0;i<s->nb_streams;i++) { st = s->streams[i]; if (st) { av_freep(&st->priv_data); av_free(st); } } return -1; } /* return < 0 if eof */ static int ffm_read_packet(AVFormatContext *s, AVPacket *pkt) { int size; FFMContext *ffm = s->priv_data; int duration; switch(ffm->read_state) { case READ_HEADER: if (!ffm_is_avail_data(s, FRAME_HEADER_SIZE)) { return AVERROR(EAGAIN); } dprintf(s, "pos=%08"PRIx64" spos=%"PRIx64", write_index=%"PRIx64" size=%"PRIx64"\n", url_ftell(s->pb), s->pb.pos, ffm->write_index, ffm->file_size); if (ffm_read_data(s, ffm->header, FRAME_HEADER_SIZE, 1) != FRAME_HEADER_SIZE) return AVERROR(EAGAIN); #if 0 av_hexdump_log(s, AV_LOG_DEBUG, ffm->header, FRAME_HEADER_SIZE); #endif ffm->read_state = READ_DATA; /* fall thru */ case READ_DATA: size = AV_RB24(ffm->header + 2); if (!ffm_is_avail_data(s, size)) { return AVERROR(EAGAIN); } duration = AV_RB24(ffm->header + 5); av_new_packet(pkt, size); pkt->stream_index = ffm->header[0]; if ((unsigned)pkt->stream_index >= s->nb_streams) { av_log(s, AV_LOG_ERROR, "invalid stream index %d\n", pkt->stream_index); av_free_packet(pkt); ffm->read_state = READ_HEADER; return AVERROR(EAGAIN); } pkt->pos = url_ftell(s->pb); if (ffm->header[1] & FLAG_KEY_FRAME) pkt->flags |= PKT_FLAG_KEY; ffm->read_state = READ_HEADER; if (ffm_read_data(s, pkt->data, size, 0) != size) { /* bad case: desynchronized packet. we cancel all the packet loading */ av_free_packet(pkt); return AVERROR(EAGAIN); } if (ffm->first_frame_in_packet) { pkt->pts = ffm->pts; ffm->first_frame_in_packet = 0; } pkt->duration = duration; break; } return 0; } /* seek to a given time in the file. The file read pointer is positioned at or before pts. XXX: the following code is quite approximative */ static int ffm_seek(AVFormatContext *s, int stream_index, int64_t wanted_pts, int flags) { FFMContext *ffm = s->priv_data; offset_t pos_min, pos_max, pos; int64_t pts_min, pts_max, pts; double pos1; #ifdef DEBUG_SEEK av_log(s, AV_LOG_DEBUG, "wanted_pts=%0.6f\n", wanted_pts / 1000000.0); #endif /* find the position using linear interpolation (better than dichotomy in typical cases) */ pos_min = 0; pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE; while (pos_min <= pos_max) { pts_min = get_pts(s, pos_min); pts_max = get_pts(s, pos_max); /* linear interpolation */ pos1 = (double)(pos_max - pos_min) * (double)(wanted_pts - pts_min) / (double)(pts_max - pts_min); pos = (((int64_t)pos1) / FFM_PACKET_SIZE) * FFM_PACKET_SIZE; if (pos <= pos_min) pos = pos_min; else if (pos >= pos_max) pos = pos_max; pts = get_pts(s, pos); /* check if we are lucky */ if (pts == wanted_pts) { goto found; } else if (pts > wanted_pts) { pos_max = pos - FFM_PACKET_SIZE; } else { pos_min = pos + FFM_PACKET_SIZE; } } pos = (flags & AVSEEK_FLAG_BACKWARD) ? pos_min : pos_max; if (pos > 0) pos -= FFM_PACKET_SIZE; found: ffm_seek1(s, pos); return 0; } static int ffm_read_close(AVFormatContext *s) { AVStream *st; int i; for(i=0;i<s->nb_streams;i++) { st = s->streams[i]; av_freep(&st->priv_data); } return 0; } static int ffm_probe(AVProbeData *p) { if ( p->buf[0] == 'F' && p->buf[1] == 'F' && p->buf[2] == 'M' && p->buf[3] == '1') return AVPROBE_SCORE_MAX + 1; return 0; } AVInputFormat ffm_demuxer = { "ffm", "ffm format", sizeof(FFMContext), ffm_probe, ffm_read_header, ffm_read_packet, ffm_read_close, ffm_seek, };