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637 lines
21 KiB
637 lines
21 KiB
/* |
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* FFM (ffserver live feed) demuxer |
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* Copyright (c) 2001 Fabrice Bellard |
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* |
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* This file is part of FFmpeg. |
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* |
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* FFmpeg is free software; you can redistribute it and/or |
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* modify it under the terms of the GNU Lesser General Public |
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* License as published by the Free Software Foundation; either |
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* version 2.1 of the License, or (at your option) any later version. |
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* |
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* FFmpeg is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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* Lesser General Public License for more details. |
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* |
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* You should have received a copy of the GNU Lesser General Public |
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* License along with FFmpeg; if not, write to the Free Software |
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
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*/ |
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|
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#include <stdint.h> |
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|
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#include "libavutil/intreadwrite.h" |
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#include "libavutil/intfloat.h" |
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#include "avformat.h" |
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#include "internal.h" |
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#include "ffm.h" |
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#include "avio_internal.h" |
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static int ffm_is_avail_data(AVFormatContext *s, int size) |
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{ |
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FFMContext *ffm = s->priv_data; |
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int64_t pos, avail_size; |
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int len; |
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len = ffm->packet_end - ffm->packet_ptr; |
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if (size <= len) |
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return 1; |
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pos = avio_tell(s->pb); |
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if (!ffm->write_index) { |
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if (pos == ffm->file_size) |
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return AVERROR_EOF; |
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avail_size = ffm->file_size - pos; |
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} else { |
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if (pos == ffm->write_index) { |
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/* exactly at the end of stream */ |
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return AVERROR(EAGAIN); |
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} else if (pos < ffm->write_index) { |
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avail_size = ffm->write_index - pos; |
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} else { |
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avail_size = (ffm->file_size - pos) + (ffm->write_index - FFM_PACKET_SIZE); |
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} |
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} |
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avail_size = (avail_size / ffm->packet_size) * (ffm->packet_size - FFM_HEADER_SIZE) + len; |
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if (size <= avail_size) |
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return 1; |
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else |
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return AVERROR(EAGAIN); |
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} |
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static int ffm_resync(AVFormatContext *s, int state) |
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{ |
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av_log(s, AV_LOG_ERROR, "resyncing\n"); |
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while (state != PACKET_ID) { |
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if (url_feof(s->pb)) { |
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av_log(s, AV_LOG_ERROR, "cannot find FFM syncword\n"); |
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return -1; |
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} |
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state = (state << 8) | avio_r8(s->pb); |
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} |
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return 0; |
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} |
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|
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/* first is true if we read the frame header */ |
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static int ffm_read_data(AVFormatContext *s, |
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uint8_t *buf, int size, int header) |
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{ |
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FFMContext *ffm = s->priv_data; |
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AVIOContext *pb = s->pb; |
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int len, fill_size, size1, frame_offset, id; |
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size1 = size; |
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while (size > 0) { |
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redo: |
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len = ffm->packet_end - ffm->packet_ptr; |
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if (len < 0) |
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return -1; |
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if (len > size) |
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len = size; |
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if (len == 0) { |
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if (avio_tell(pb) == ffm->file_size) |
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avio_seek(pb, ffm->packet_size, SEEK_SET); |
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retry_read: |
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if (pb->buffer_size != ffm->packet_size) { |
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int64_t tell = avio_tell(pb); |
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ffio_set_buf_size(pb, ffm->packet_size); |
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avio_seek(pb, tell, SEEK_SET); |
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} |
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id = avio_rb16(pb); /* PACKET_ID */ |
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if (id != PACKET_ID) |
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if (ffm_resync(s, id) < 0) |
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return -1; |
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fill_size = avio_rb16(pb); |
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ffm->dts = avio_rb64(pb); |
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frame_offset = avio_rb16(pb); |
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avio_read(pb, ffm->packet, ffm->packet_size - FFM_HEADER_SIZE); |
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ffm->packet_end = ffm->packet + (ffm->packet_size - FFM_HEADER_SIZE - fill_size); |
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if (ffm->packet_end < ffm->packet || frame_offset < 0) |
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return -1; |
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/* if first packet or resynchronization packet, we must |
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handle it specifically */ |
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if (ffm->first_packet || (frame_offset & 0x8000)) { |
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if (!frame_offset) { |
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/* This packet has no frame headers in it */ |
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if (avio_tell(pb) >= ffm->packet_size * 3LL) { |
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avio_seek(pb, -ffm->packet_size * 2LL, SEEK_CUR); |
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goto retry_read; |
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} |
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/* This is bad, we cannot find a valid frame header */ |
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return 0; |
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} |
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ffm->first_packet = 0; |
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if ((frame_offset & 0x7fff) < FFM_HEADER_SIZE) |
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return -1; |
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ffm->packet_ptr = ffm->packet + (frame_offset & 0x7fff) - FFM_HEADER_SIZE; |
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if (!header) |
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break; |
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} else { |
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ffm->packet_ptr = ffm->packet; |
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} |
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goto redo; |
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} |
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memcpy(buf, ffm->packet_ptr, len); |
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buf += len; |
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ffm->packet_ptr += len; |
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size -= len; |
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header = 0; |
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} |
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return size1 - size; |
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} |
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/* ensure that acutal seeking happens between FFM_PACKET_SIZE |
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and file_size - FFM_PACKET_SIZE */ |
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static int64_t ffm_seek1(AVFormatContext *s, int64_t pos1) |
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{ |
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FFMContext *ffm = s->priv_data; |
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AVIOContext *pb = s->pb; |
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int64_t pos; |
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pos = FFMIN(pos1, ffm->file_size - FFM_PACKET_SIZE); |
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pos = FFMAX(pos, FFM_PACKET_SIZE); |
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av_dlog(s, "seek to %"PRIx64" -> %"PRIx64"\n", pos1, pos); |
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return avio_seek(pb, pos, SEEK_SET); |
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} |
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static int64_t get_dts(AVFormatContext *s, int64_t pos) |
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{ |
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AVIOContext *pb = s->pb; |
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int64_t dts; |
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ffm_seek1(s, pos); |
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avio_skip(pb, 4); |
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dts = avio_rb64(pb); |
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av_dlog(s, "dts=%0.6f\n", dts / 1000000.0); |
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return dts; |
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} |
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static void adjust_write_index(AVFormatContext *s) |
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{ |
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FFMContext *ffm = s->priv_data; |
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AVIOContext *pb = s->pb; |
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int64_t pts; |
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//int64_t orig_write_index = ffm->write_index; |
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int64_t pos_min, pos_max; |
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int64_t pts_start; |
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int64_t ptr = avio_tell(pb); |
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pos_min = 0; |
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pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE; |
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pts_start = get_dts(s, pos_min); |
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pts = get_dts(s, pos_max); |
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if (pts - 100000 > pts_start) |
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goto end; |
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ffm->write_index = FFM_PACKET_SIZE; |
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pts_start = get_dts(s, pos_min); |
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pts = get_dts(s, pos_max); |
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if (pts - 100000 <= pts_start) { |
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while (1) { |
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int64_t newpos; |
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int64_t newpts; |
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newpos = ((pos_max + pos_min) / (2 * FFM_PACKET_SIZE)) * FFM_PACKET_SIZE; |
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if (newpos == pos_min) |
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break; |
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newpts = get_dts(s, newpos); |
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if (newpts - 100000 <= pts) { |
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pos_max = newpos; |
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pts = newpts; |
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} else { |
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pos_min = newpos; |
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} |
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} |
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ffm->write_index += pos_max; |
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} |
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end: |
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avio_seek(pb, ptr, SEEK_SET); |
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} |
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static int ffm_close(AVFormatContext *s) |
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{ |
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int i; |
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for (i = 0; i < s->nb_streams; i++) |
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av_freep(&s->streams[i]->codec->rc_eq); |
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return 0; |
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} |
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static int ffm2_read_header(AVFormatContext *s) |
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{ |
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FFMContext *ffm = s->priv_data; |
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AVStream *st; |
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AVIOContext *pb = s->pb; |
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AVCodecContext *codec; |
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ffm->packet_size = avio_rb32(pb); |
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if (ffm->packet_size != FFM_PACKET_SIZE) |
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goto fail; |
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ffm->write_index = avio_rb64(pb); |
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/* get also filesize */ |
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if (pb->seekable) { |
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ffm->file_size = avio_size(pb); |
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if (ffm->write_index && 0) |
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adjust_write_index(s); |
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} else { |
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ffm->file_size = (UINT64_C(1) << 63) - 1; |
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} |
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while(!url_feof(pb)) { |
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unsigned id = avio_rb32(pb); |
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unsigned size = avio_rb32(pb); |
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int64_t next = avio_tell(pb) + size; |
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char rc_eq_buf[128]; |
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if(!id) |
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break; |
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switch(id) { |
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case MKBETAG('M', 'A', 'I', 'N'): |
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avio_rb32(pb); /* nb_streams */ |
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avio_rb32(pb); /* total bitrate */ |
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break; |
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case MKBETAG('C', 'O', 'M', 'M'): |
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st = avformat_new_stream(s, NULL); |
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if (!st) |
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goto fail; |
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avpriv_set_pts_info(st, 64, 1, 1000000); |
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codec = st->codec; |
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/* generic info */ |
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codec->codec_id = avio_rb32(pb); |
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codec->codec_type = avio_r8(pb); |
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codec->bit_rate = avio_rb32(pb); |
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codec->flags = avio_rb32(pb); |
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codec->flags2 = avio_rb32(pb); |
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codec->debug = avio_rb32(pb); |
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if (codec->flags & CODEC_FLAG_GLOBAL_HEADER) { |
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if (ff_alloc_extradata(codec, avio_rb32(pb))) |
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return AVERROR(ENOMEM); |
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avio_read(pb, codec->extradata, codec->extradata_size); |
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} |
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avio_seek(pb, next, SEEK_SET); |
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id = avio_rb32(pb); |
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size = avio_rb32(pb); |
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next = avio_tell(pb) + size; |
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switch(id) { |
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case MKBETAG('S', 'T', 'V', 'I'): |
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codec->time_base.num = avio_rb32(pb); |
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codec->time_base.den = avio_rb32(pb); |
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codec->width = avio_rb16(pb); |
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codec->height = avio_rb16(pb); |
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codec->gop_size = avio_rb16(pb); |
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codec->pix_fmt = avio_rb32(pb); |
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codec->qmin = avio_r8(pb); |
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codec->qmax = avio_r8(pb); |
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codec->max_qdiff = avio_r8(pb); |
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codec->qcompress = avio_rb16(pb) / 10000.0; |
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codec->qblur = avio_rb16(pb) / 10000.0; |
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codec->bit_rate_tolerance = avio_rb32(pb); |
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avio_get_str(pb, INT_MAX, rc_eq_buf, sizeof(rc_eq_buf)); |
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codec->rc_eq = av_strdup(rc_eq_buf); |
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codec->rc_max_rate = avio_rb32(pb); |
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codec->rc_min_rate = avio_rb32(pb); |
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codec->rc_buffer_size = avio_rb32(pb); |
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codec->i_quant_factor = av_int2double(avio_rb64(pb)); |
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codec->b_quant_factor = av_int2double(avio_rb64(pb)); |
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codec->i_quant_offset = av_int2double(avio_rb64(pb)); |
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codec->b_quant_offset = av_int2double(avio_rb64(pb)); |
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codec->dct_algo = avio_rb32(pb); |
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codec->strict_std_compliance = avio_rb32(pb); |
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codec->max_b_frames = avio_rb32(pb); |
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codec->mpeg_quant = avio_rb32(pb); |
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codec->intra_dc_precision = avio_rb32(pb); |
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codec->me_method = avio_rb32(pb); |
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codec->mb_decision = avio_rb32(pb); |
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codec->nsse_weight = avio_rb32(pb); |
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codec->frame_skip_cmp = avio_rb32(pb); |
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codec->rc_buffer_aggressivity = av_int2double(avio_rb64(pb)); |
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codec->codec_tag = avio_rb32(pb); |
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codec->thread_count = avio_r8(pb); |
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codec->coder_type = avio_rb32(pb); |
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codec->me_cmp = avio_rb32(pb); |
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codec->me_subpel_quality = avio_rb32(pb); |
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codec->me_range = avio_rb32(pb); |
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codec->keyint_min = avio_rb32(pb); |
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codec->scenechange_threshold = avio_rb32(pb); |
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codec->b_frame_strategy = avio_rb32(pb); |
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codec->qcompress = av_int2double(avio_rb64(pb)); |
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codec->qblur = av_int2double(avio_rb64(pb)); |
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codec->max_qdiff = avio_rb32(pb); |
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codec->refs = avio_rb32(pb); |
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break; |
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case MKBETAG('S', 'T', 'A', 'U'): |
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codec->sample_rate = avio_rb32(pb); |
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codec->channels = avio_rl16(pb); |
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codec->frame_size = avio_rl16(pb); |
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break; |
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} |
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break; |
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} |
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avio_seek(pb, next, SEEK_SET); |
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} |
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|
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/* get until end of block reached */ |
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while ((avio_tell(pb) % ffm->packet_size) != 0) |
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avio_r8(pb); |
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|
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/* init packet demux */ |
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ffm->packet_ptr = ffm->packet; |
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ffm->packet_end = ffm->packet; |
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ffm->frame_offset = 0; |
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ffm->dts = 0; |
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ffm->read_state = READ_HEADER; |
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ffm->first_packet = 1; |
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return 0; |
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fail: |
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ffm_close(s); |
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return -1; |
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} |
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static int ffm_read_header(AVFormatContext *s) |
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{ |
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FFMContext *ffm = s->priv_data; |
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AVStream *st; |
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AVIOContext *pb = s->pb; |
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AVCodecContext *codec; |
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int i, nb_streams; |
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uint32_t tag; |
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|
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/* header */ |
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tag = avio_rl32(pb); |
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if (tag == MKTAG('F', 'F', 'M', '2')) |
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return ffm2_read_header(s); |
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if (tag != MKTAG('F', 'F', 'M', '1')) |
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goto fail; |
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ffm->packet_size = avio_rb32(pb); |
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if (ffm->packet_size != FFM_PACKET_SIZE) |
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goto fail; |
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ffm->write_index = avio_rb64(pb); |
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/* get also filesize */ |
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if (pb->seekable) { |
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ffm->file_size = avio_size(pb); |
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if (ffm->write_index && 0) |
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adjust_write_index(s); |
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} else { |
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ffm->file_size = (UINT64_C(1) << 63) - 1; |
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} |
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nb_streams = avio_rb32(pb); |
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avio_rb32(pb); /* total bitrate */ |
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/* read each stream */ |
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for(i=0;i<nb_streams;i++) { |
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char rc_eq_buf[128]; |
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st = avformat_new_stream(s, NULL); |
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if (!st) |
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goto fail; |
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avpriv_set_pts_info(st, 64, 1, 1000000); |
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codec = st->codec; |
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/* generic info */ |
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codec->codec_id = avio_rb32(pb); |
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codec->codec_type = avio_r8(pb); /* codec_type */ |
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codec->bit_rate = avio_rb32(pb); |
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codec->flags = avio_rb32(pb); |
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codec->flags2 = avio_rb32(pb); |
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codec->debug = avio_rb32(pb); |
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/* specific info */ |
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switch(codec->codec_type) { |
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case AVMEDIA_TYPE_VIDEO: |
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codec->time_base.num = avio_rb32(pb); |
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codec->time_base.den = avio_rb32(pb); |
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codec->width = avio_rb16(pb); |
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codec->height = avio_rb16(pb); |
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codec->gop_size = avio_rb16(pb); |
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codec->pix_fmt = avio_rb32(pb); |
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codec->qmin = avio_r8(pb); |
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codec->qmax = avio_r8(pb); |
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codec->max_qdiff = avio_r8(pb); |
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codec->qcompress = avio_rb16(pb) / 10000.0; |
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codec->qblur = avio_rb16(pb) / 10000.0; |
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codec->bit_rate_tolerance = avio_rb32(pb); |
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avio_get_str(pb, INT_MAX, rc_eq_buf, sizeof(rc_eq_buf)); |
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codec->rc_eq = av_strdup(rc_eq_buf); |
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codec->rc_max_rate = avio_rb32(pb); |
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codec->rc_min_rate = avio_rb32(pb); |
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codec->rc_buffer_size = avio_rb32(pb); |
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codec->i_quant_factor = av_int2double(avio_rb64(pb)); |
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codec->b_quant_factor = av_int2double(avio_rb64(pb)); |
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codec->i_quant_offset = av_int2double(avio_rb64(pb)); |
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codec->b_quant_offset = av_int2double(avio_rb64(pb)); |
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codec->dct_algo = avio_rb32(pb); |
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codec->strict_std_compliance = avio_rb32(pb); |
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codec->max_b_frames = avio_rb32(pb); |
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codec->mpeg_quant = avio_rb32(pb); |
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codec->intra_dc_precision = avio_rb32(pb); |
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codec->me_method = avio_rb32(pb); |
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codec->mb_decision = avio_rb32(pb); |
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codec->nsse_weight = avio_rb32(pb); |
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codec->frame_skip_cmp = avio_rb32(pb); |
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codec->rc_buffer_aggressivity = av_int2double(avio_rb64(pb)); |
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codec->codec_tag = avio_rb32(pb); |
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codec->thread_count = avio_r8(pb); |
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codec->coder_type = avio_rb32(pb); |
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codec->me_cmp = avio_rb32(pb); |
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codec->me_subpel_quality = avio_rb32(pb); |
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codec->me_range = avio_rb32(pb); |
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codec->keyint_min = avio_rb32(pb); |
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codec->scenechange_threshold = avio_rb32(pb); |
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codec->b_frame_strategy = avio_rb32(pb); |
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codec->qcompress = av_int2double(avio_rb64(pb)); |
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codec->qblur = av_int2double(avio_rb64(pb)); |
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codec->max_qdiff = avio_rb32(pb); |
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codec->refs = avio_rb32(pb); |
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break; |
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case AVMEDIA_TYPE_AUDIO: |
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codec->sample_rate = avio_rb32(pb); |
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codec->channels = avio_rl16(pb); |
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codec->frame_size = avio_rl16(pb); |
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break; |
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default: |
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goto fail; |
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} |
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if (codec->flags & CODEC_FLAG_GLOBAL_HEADER) { |
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if (ff_alloc_extradata(codec, avio_rb32(pb))) |
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return AVERROR(ENOMEM); |
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avio_read(pb, codec->extradata, codec->extradata_size); |
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} |
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} |
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|
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/* get until end of block reached */ |
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while ((avio_tell(pb) % ffm->packet_size) != 0) |
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avio_r8(pb); |
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|
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/* init packet demux */ |
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ffm->packet_ptr = ffm->packet; |
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ffm->packet_end = ffm->packet; |
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ffm->frame_offset = 0; |
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ffm->dts = 0; |
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ffm->read_state = READ_HEADER; |
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ffm->first_packet = 1; |
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return 0; |
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fail: |
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ffm_close(s); |
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return -1; |
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} |
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|
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/* return < 0 if eof */ |
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static int ffm_read_packet(AVFormatContext *s, AVPacket *pkt) |
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{ |
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int size; |
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FFMContext *ffm = s->priv_data; |
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int duration, ret; |
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|
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switch(ffm->read_state) { |
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case READ_HEADER: |
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if ((ret = ffm_is_avail_data(s, FRAME_HEADER_SIZE+4)) < 0) |
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return ret; |
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|
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av_dlog(s, "pos=%08"PRIx64" spos=%"PRIx64", write_index=%"PRIx64" size=%"PRIx64"\n", |
|
avio_tell(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 -1; |
|
if (ffm->header[1] & FLAG_DTS) |
|
if (ffm_read_data(s, ffm->header+16, 4, 1) != 4) |
|
return -1; |
|
ffm->read_state = READ_DATA; |
|
/* fall thru */ |
|
case READ_DATA: |
|
size = AV_RB24(ffm->header + 2); |
|
if ((ret = ffm_is_avail_data(s, size)) < 0) |
|
return ret; |
|
|
|
duration = AV_RB24(ffm->header + 5); |
|
|
|
if (av_new_packet(pkt, size) < 0) { |
|
return AVERROR(ENOMEM); |
|
} |
|
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 -1; |
|
} |
|
pkt->pos = avio_tell(s->pb); |
|
if (ffm->header[1] & FLAG_KEY_FRAME) |
|
pkt->flags |= AV_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 -1; |
|
} |
|
pkt->pts = AV_RB64(ffm->header+8); |
|
if (ffm->header[1] & FLAG_DTS) |
|
pkt->dts = pkt->pts - AV_RB32(ffm->header+16); |
|
else |
|
pkt->dts = pkt->pts; |
|
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; |
|
int64_t pos_min, pos_max, pos; |
|
int64_t pts_min, pts_max, pts; |
|
double pos1; |
|
|
|
av_dlog(s, "wanted_pts=%0.6f\n", wanted_pts / 1000000.0); |
|
/* find the position using linear interpolation (better than |
|
dichotomy in typical cases) */ |
|
if (ffm->write_index && ffm->write_index < ffm->file_size) { |
|
if (get_dts(s, FFM_PACKET_SIZE) < wanted_pts) { |
|
pos_min = FFM_PACKET_SIZE; |
|
pos_max = ffm->write_index - FFM_PACKET_SIZE; |
|
} else { |
|
pos_min = ffm->write_index; |
|
pos_max = ffm->file_size - FFM_PACKET_SIZE; |
|
} |
|
} else { |
|
pos_min = FFM_PACKET_SIZE; |
|
pos_max = ffm->file_size - FFM_PACKET_SIZE; |
|
} |
|
while (pos_min <= pos_max) { |
|
pts_min = get_dts(s, pos_min); |
|
pts_max = get_dts(s, pos_max); |
|
if (pts_min > wanted_pts || pts_max <= wanted_pts) { |
|
pos = pts_min > wanted_pts ? pos_min : pos_max; |
|
goto found; |
|
} |
|
/* 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_dts(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; |
|
|
|
found: |
|
if (ffm_seek1(s, pos) < 0) |
|
return -1; |
|
|
|
/* reset read state */ |
|
ffm->read_state = READ_HEADER; |
|
ffm->packet_ptr = ffm->packet; |
|
ffm->packet_end = ffm->packet; |
|
ffm->first_packet = 1; |
|
|
|
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' || p->buf[3] == '2')) |
|
return AVPROBE_SCORE_MAX + 1; |
|
return 0; |
|
} |
|
|
|
AVInputFormat ff_ffm_demuxer = { |
|
.name = "ffm", |
|
.long_name = NULL_IF_CONFIG_SMALL("FFM (FFserver live feed)"), |
|
.priv_data_size = sizeof(FFMContext), |
|
.read_probe = ffm_probe, |
|
.read_header = ffm_read_header, |
|
.read_packet = ffm_read_packet, |
|
.read_close = ffm_close, |
|
.read_seek = ffm_seek, |
|
};
|
|
|