mirror of
https://git.ffmpeg.org/ffmpeg.git
synced 2024-12-25 00:32:31 +00:00
a807c68253
Signed-off-by: Paul B Mahol <onemda@gmail.com>
636 lines
21 KiB
C
636 lines
21 KiB
C
/*
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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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#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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/* 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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/* 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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/* 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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/* 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);
|
|
codec->scenechange_threshold = avio_rb32(pb);
|
|
codec->b_frame_strategy = avio_rb32(pb);
|
|
codec->qcompress = av_int2double(avio_rb64(pb));
|
|
codec->qblur = av_int2double(avio_rb64(pb));
|
|
codec->max_qdiff = avio_rb32(pb);
|
|
codec->refs = avio_rb32(pb);
|
|
break;
|
|
case AVMEDIA_TYPE_AUDIO:
|
|
codec->sample_rate = avio_rb32(pb);
|
|
codec->channels = avio_rl16(pb);
|
|
codec->frame_size = avio_rl16(pb);
|
|
break;
|
|
default:
|
|
goto fail;
|
|
}
|
|
if (codec->flags & CODEC_FLAG_GLOBAL_HEADER) {
|
|
if (ff_alloc_extradata(codec, avio_rb32(pb)))
|
|
return AVERROR(ENOMEM);
|
|
avio_read(pb, codec->extradata, codec->extradata_size);
|
|
}
|
|
}
|
|
|
|
/* get until end of block reached */
|
|
while ((avio_tell(pb) % ffm->packet_size) != 0)
|
|
avio_r8(pb);
|
|
|
|
/* init packet demux */
|
|
ffm->packet_ptr = ffm->packet;
|
|
ffm->packet_end = ffm->packet;
|
|
ffm->frame_offset = 0;
|
|
ffm->dts = 0;
|
|
ffm->read_state = READ_HEADER;
|
|
ffm->first_packet = 1;
|
|
return 0;
|
|
fail:
|
|
ffm_close(s);
|
|
return -1;
|
|
}
|
|
|
|
/* return < 0 if eof */
|
|
static int ffm_read_packet(AVFormatContext *s, AVPacket *pkt)
|
|
{
|
|
int size;
|
|
FFMContext *ffm = s->priv_data;
|
|
int duration, ret;
|
|
|
|
switch(ffm->read_state) {
|
|
case READ_HEADER:
|
|
if ((ret = ffm_is_avail_data(s, FRAME_HEADER_SIZE+4)) < 0)
|
|
return ret;
|
|
|
|
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,
|
|
};
|