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/*****************************************************************************
* ps.c: Program Stream demux module for VLC.
*****************************************************************************
* Copyright (C) 2004-2009 VLC authors and VideoLAN
* $Id$
*
* Authors: Laurent Aimar <fenrir@via.ecp.fr>
*
* This program 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.
*
* This program 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 this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
/*****************************************************************************
* Preamble
*****************************************************************************/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <vlc_common.h>
#include <vlc_plugin.h>
#include <vlc_demux.h>
#include "ps.h"
/* TODO:
* - re-add pre-scanning.
* - ...
*/
#define TIME_TEXT N_("Trust MPEG timestamps")
#define TIME_LONGTEXT N_("Normally we use the timestamps of the MPEG files " \
"to calculate position and duration. However sometimes this might not " \
"be usable. Disable this option to calculate from the bitrate instead." )
/*****************************************************************************
* Module descriptor
*****************************************************************************/
static int OpenForce( vlc_object_t * );
static int Open ( vlc_object_t * );
static void Close ( vlc_object_t * );
vlc_module_begin ()
set_description( N_("MPEG-PS demuxer") )
set_shortname( N_("PS") )
set_category( CAT_INPUT )
set_subcategory( SUBCAT_INPUT_DEMUX )
set_capability( "demux", 1 )
set_callbacks( OpenForce, Close )
add_shortcut( "ps" )
add_bool( "ps-trust-timestamps", true, TIME_TEXT,
TIME_LONGTEXT, true )
change_safe ()
add_submodule ()
set_description( N_("MPEG-PS demuxer") )
set_capability( "demux", 8 )
set_callbacks( Open, Close )
add_shortcut( "ps" )
vlc_module_end ()
/*****************************************************************************
* Local prototypes
*****************************************************************************/
struct demux_sys_t
{
ps_psm_t psm;
ps_track_t tk[PS_TK_COUNT];
int64_t i_scr;
int64_t i_last_scr;
int i_mux_rate;
int64_t i_length;
int i_time_track;
int64_t i_current_pts;
int i_aob_mlp_count;
bool b_lost_sync;
bool b_have_pack;
bool b_seekable;
};
static int Demux ( demux_t *p_demux );
static int Control( demux_t *p_demux, int i_query, va_list args );
static int ps_pkt_resynch( stream_t *, uint32_t *pi_code );
static block_t *ps_pkt_read ( stream_t *, uint32_t i_code );
/*****************************************************************************
* Open
*****************************************************************************/
static int OpenCommon( vlc_object_t *p_this, bool b_force )
{
demux_t *p_demux = (demux_t*)p_this;
demux_sys_t *p_sys;
const uint8_t *p_peek;
if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 )
{
msg_Err( p_demux, "cannot peek" );
return VLC_EGENERIC;
}
if( memcmp( p_peek, "\x00\x00\x01", 3 ) || ( p_peek[3] < 0xb9 ) )
{
if( !b_force )
return VLC_EGENERIC;
msg_Warn( p_demux, "this does not look like an MPEG PS stream, "
"continuing anyway" );
}
/* Fill p_demux field */
p_demux->pf_demux = Demux;
p_demux->pf_control = Control;
p_demux->p_sys = p_sys = malloc( sizeof( demux_sys_t ) );
if( !p_sys ) return VLC_ENOMEM;
/* Init p_sys */
p_sys->i_mux_rate = 0;
p_sys->i_scr = -1;
p_sys->i_last_scr = -1;
p_sys->i_length = -1;
p_sys->i_current_pts = (mtime_t) 0;
p_sys->i_time_track = -1;
p_sys->i_aob_mlp_count = 0;
p_sys->b_lost_sync = false;
p_sys->b_have_pack = false;
p_sys->b_seekable = false;
stream_Control( p_demux->s, STREAM_CAN_SEEK, &p_sys->b_seekable );
ps_psm_init( &p_sys->psm );
ps_track_init( p_sys->tk );
/* TODO prescanning of ES */
return VLC_SUCCESS;
}
static int OpenForce( vlc_object_t *p_this )
{
return OpenCommon( p_this, true );
}
static int Open( vlc_object_t *p_this )
{
return OpenCommon( p_this, ((demux_t *)p_this)->b_force );
}
/*****************************************************************************
* Close
*****************************************************************************/
static void Close( vlc_object_t *p_this )
{
demux_t *p_demux = (demux_t*)p_this;
demux_sys_t *p_sys = p_demux->p_sys;
int i;
for( i = 0; i < PS_TK_COUNT; i++ )
{
ps_track_t *tk = &p_sys->tk[i];
if( tk->b_seen )
{
es_format_Clean( &tk->fmt );
if( tk->es ) es_out_Del( p_demux->out, tk->es );
}
}
ps_psm_destroy( &p_sys->psm );
free( p_sys );
}
static int Demux2( demux_t *p_demux, bool b_end )
{
demux_sys_t *p_sys = p_demux->p_sys;
int i_ret, i_id;
uint32_t i_code;
block_t *p_pkt;
i_ret = ps_pkt_resynch( p_demux->s, &i_code );
if( i_ret < 0 )
{
return 0;
}
else if( i_ret == 0 )
{
if( !p_sys->b_lost_sync )
msg_Warn( p_demux, "garbage at input, trying to resync..." );
p_sys->b_lost_sync = true;
return 1;
}
if( p_sys->b_lost_sync ) msg_Warn( p_demux, "found sync code" );
p_sys->b_lost_sync = false;
if( ( p_pkt = ps_pkt_read( p_demux->s, i_code ) ) == NULL )
{
return 0;
}
if( (i_id = ps_pkt_id( p_pkt )) >= 0xc0 )
{
ps_track_t *tk = &p_sys->tk[PS_ID_TO_TK(i_id)];
if( !ps_pkt_parse_pes( p_pkt, tk->i_skip ) && p_pkt->i_pts > VLC_TS_INVALID )
{
if( b_end && p_pkt->i_pts > tk->i_last_pts )
{
tk->i_last_pts = p_pkt->i_pts;
}
else if ( tk->i_first_pts == -1 )
{
tk->i_first_pts = p_pkt->i_pts;
}
}
}
block_Release( p_pkt );
return 1;
}
static void FindLength( demux_t *p_demux )
{
demux_sys_t *p_sys = p_demux->p_sys;
int64_t i_current_pos = -1, i_size = 0, i_end = 0;
if( !var_CreateGetBool( p_demux, "ps-trust-timestamps" ) )
return;
if( p_sys->i_length == -1 ) /* First time */
{
p_sys->i_length = 0;
/* Check beginning */
int i = 0;
i_current_pos = stream_Tell( p_demux->s );
while( vlc_object_alive (p_demux) && i < 40 && Demux2( p_demux, false ) > 0 ) i++;
/* Check end */
i_size = stream_Size( p_demux->s );
i_end = VLC_CLIP( i_size, 0, 200000 );
stream_Seek( p_demux->s, i_size - i_end );
i = 0;
while( vlc_object_alive (p_demux) && i < 40 && Demux2( p_demux, true ) > 0 ) i++;
if( i_current_pos >= 0 ) stream_Seek( p_demux->s, i_current_pos );
}
/* Find the longest track */
for( int i = 0; i < PS_TK_COUNT; i++ )
{
ps_track_t *tk = &p_sys->tk[i];
if( tk->i_first_pts >= 0 && tk->i_last_pts > 0 &&
tk->i_last_pts > tk->i_first_pts )
{
int64_t i_length = (int64_t)tk->i_last_pts - tk->i_first_pts;
if( i_length > p_sys->i_length )
{
p_sys->i_length = i_length;
p_sys->i_time_track = i;
msg_Dbg( p_demux, "we found a length of: %"PRId64, p_sys->i_length );
}
}
}
}
/*****************************************************************************
* Demux:
*****************************************************************************/
static int Demux( demux_t *p_demux )
{
demux_sys_t *p_sys = p_demux->p_sys;
int i_ret, i_id, i_mux_rate;
uint32_t i_code;
block_t *p_pkt;
i_ret = ps_pkt_resynch( p_demux->s, &i_code );
if( i_ret < 0 )
{
return 0;
}
else if( i_ret == 0 )
{
if( !p_sys->b_lost_sync )
msg_Warn( p_demux, "garbage at input, trying to resync..." );
p_sys->b_lost_sync = true;
return 1;
}
if( p_sys->b_lost_sync ) msg_Warn( p_demux, "found sync code" );
p_sys->b_lost_sync = false;
if( p_sys->i_length < 0 && p_sys->b_seekable )
FindLength( p_demux );
if( ( p_pkt = ps_pkt_read( p_demux->s, i_code ) ) == NULL )
{
return 0;
}
switch( i_code )
{
case 0x1b9:
block_Release( p_pkt );
break;
case 0x1ba:
if( !ps_pkt_parse_pack( p_pkt, &p_sys->i_scr, &i_mux_rate ) )
{
p_sys->i_last_scr = p_sys->i_scr;
if( !p_sys->b_have_pack ) p_sys->b_have_pack = true;
/* done later on to work around bad vcd/svcd streams */
/* es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_sys->i_scr ); */
if( i_mux_rate > 0 ) p_sys->i_mux_rate = i_mux_rate;
}
block_Release( p_pkt );
break;
case 0x1bb:
if( !ps_pkt_parse_system( p_pkt, &p_sys->psm, p_sys->tk ) )
{
int i;
for( i = 0; i < PS_TK_COUNT; i++ )
{
ps_track_t *tk = &p_sys->tk[i];
if( tk->b_seen && !tk->es && tk->fmt.i_cat != UNKNOWN_ES )
{
tk->es = es_out_Add( p_demux->out, &tk->fmt );
}
}
}
block_Release( p_pkt );
break;
case 0x1bc:
if( p_sys->psm.i_version == 0xFFFF )
msg_Dbg( p_demux, "contains a PSM");
ps_psm_fill( &p_sys->psm, p_pkt, p_sys->tk, p_demux->out );
block_Release( p_pkt );
break;
default:
if( (i_id = ps_pkt_id( p_pkt )) >= 0xc0 )
{
/* Small heuristic to improve MLP detection from AOB */
if( i_id == 0xa001 &&
p_sys->i_aob_mlp_count < 500 )
{
p_sys->i_aob_mlp_count++;
}
else if( i_id == 0xbda1 &&
p_sys->i_aob_mlp_count > 0 )
{
p_sys->i_aob_mlp_count--;
i_id = 0xa001;
}
bool b_new = false;
ps_track_t *tk = &p_sys->tk[PS_ID_TO_TK(i_id)];
if( !tk->b_seen )
{
if( !ps_track_fill( tk, &p_sys->psm, i_id ) )
{
tk->es = es_out_Add( p_demux->out, &tk->fmt );
b_new = true;
}
else
{
msg_Dbg( p_demux, "es id=0x%x format unknown", i_id );
}
tk->b_seen = true;
}
/* The popular VCD/SVCD subtitling WinSubMux does not
* renumber the SCRs when merging subtitles into the PES */
if( tk->b_seen &&
( tk->fmt.i_codec == VLC_CODEC_OGT ||
tk->fmt.i_codec == VLC_CODEC_CVD ) )
{
p_sys->i_scr = -1;
p_sys->i_last_scr = -1;
}
if( p_sys->i_scr >= 0 )
es_out_Control( p_demux->out, ES_OUT_SET_PCR, VLC_TS_0 + p_sys->i_scr );
p_sys->i_scr = -1;
if( tk->b_seen && tk->es &&
!ps_pkt_parse_pes( p_pkt, tk->i_skip ) )
{
if( !b_new && !p_sys->b_have_pack &&
(tk->fmt.i_cat == AUDIO_ES) &&
(p_pkt->i_pts > VLC_TS_INVALID) )
{
/* A hack to sync the A/V on PES files. */
msg_Dbg( p_demux, "force SCR: %"PRId64, p_pkt->i_pts );
es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_pkt->i_pts );
}
if( tk->fmt.i_codec == VLC_CODEC_TELETEXT &&
p_pkt->i_pts <= VLC_TS_INVALID && p_sys->i_last_scr >= 0 )
{
/* Teletext may have missing PTS (ETSI EN 300 472 Annexe A)
* In this case use the last SCR + 40ms */
p_pkt->i_pts = VLC_TS_0 + p_sys->i_last_scr + 40000;
}
if( (int64_t)p_pkt->i_pts > p_sys->i_current_pts )
{
p_sys->i_current_pts = (int64_t)p_pkt->i_pts;
}
es_out_Send( p_demux->out, tk->es, p_pkt );
}
else
{
block_Release( p_pkt );
}
}
else
{
block_Release( p_pkt );
}
break;
}
return 1;
}
/*****************************************************************************
* Control:
*****************************************************************************/
static int Control( demux_t *p_demux, int i_query, va_list args )
{
demux_sys_t *p_sys = p_demux->p_sys;
double f, *pf;
int64_t i64, *pi64;
switch( i_query )
{
case DEMUX_GET_POSITION:
pf = (double*) va_arg( args, double* );
i64 = stream_Size( p_demux->s );
if( i64 > 0 )
{
double current = stream_Tell( p_demux->s );
*pf = current / (double)i64;
}
else
{
*pf = 0.0;
}
return VLC_SUCCESS;
case DEMUX_SET_POSITION:
f = (double) va_arg( args, double );
i64 = stream_Size( p_demux->s );
p_sys->i_current_pts = 0;
p_sys->i_last_scr = -1;
return stream_Seek( p_demux->s, (int64_t)(i64 * f) );
case DEMUX_GET_TIME:
pi64 = (int64_t*)va_arg( args, int64_t * );
if( p_sys->i_time_track >= 0 && p_sys->i_current_pts > 0 )
{
*pi64 = p_sys->i_current_pts - p_sys->tk[p_sys->i_time_track].i_first_pts;
return VLC_SUCCESS;
}
if( p_sys->i_mux_rate > 0 )
{
*pi64 = (int64_t)1000000 * ( stream_Tell( p_demux->s ) / 50 ) /
p_sys->i_mux_rate;
return VLC_SUCCESS;
}
*pi64 = 0;
return VLC_EGENERIC;
case DEMUX_GET_LENGTH:
pi64 = (int64_t*)va_arg( args, int64_t * );
if( p_sys->i_length > 0 )
{
*pi64 = p_sys->i_length;
return VLC_SUCCESS;
}
else if( p_sys->i_mux_rate > 0 )
{
*pi64 = (int64_t)1000000 * ( stream_Size( p_demux->s ) / 50 ) /
p_sys->i_mux_rate;
return VLC_SUCCESS;
}
*pi64 = 0;
return VLC_EGENERIC;
case DEMUX_SET_TIME:
i64 = (int64_t)va_arg( args, int64_t );
if( p_sys->i_time_track >= 0 && p_sys->i_current_pts > 0 )
{
int64_t i_now = p_sys->i_current_pts - p_sys->tk[p_sys->i_time_track].i_first_pts;
int64_t i_pos = stream_Tell( p_demux->s );
if( !i_now )
return i64 ? VLC_EGENERIC : VLC_SUCCESS;
p_sys->i_current_pts = 0;
p_sys->i_last_scr = -1;
i_pos *= (float)i64 / (float)i_now;
stream_Seek( p_demux->s, i_pos );
return VLC_SUCCESS;
}
return VLC_EGENERIC;
case DEMUX_GET_FPS:
default:
return VLC_EGENERIC;
}
}
/*****************************************************************************
* Divers:
*****************************************************************************/
/* PSResynch: resynch on a system startcode
* It doesn't skip more than 512 bytes
* -1 -> error, 0 -> not synch, 1 -> ok
*/
static int ps_pkt_resynch( stream_t *s, uint32_t *pi_code )
{
const uint8_t *p_peek;
int i_peek;
int i_skip;
if( stream_Peek( s, &p_peek, 4 ) < 4 )
{
return -1;
}
if( p_peek[0] == 0 && p_peek[1] == 0 && p_peek[2] == 1 &&
p_peek[3] >= 0xb9 )
{
*pi_code = 0x100 | p_peek[3];
return 1;
}
if( ( i_peek = stream_Peek( s, &p_peek, 512 ) ) < 4 )
{
return -1;
}
i_skip = 0;
for( ;; )
{
if( i_peek < 4 )
{
break;
}
if( p_peek[0] == 0 && p_peek[1] == 0 && p_peek[2] == 1 &&
p_peek[3] >= 0xb9 )
{
*pi_code = 0x100 | p_peek[3];
return stream_Read( s, NULL, i_skip ) == i_skip ? 1 : -1;
}
p_peek++;
i_peek--;
i_skip++;
}
return stream_Read( s, NULL, i_skip ) == i_skip ? 0 : -1;
}
static block_t *ps_pkt_read( stream_t *s, uint32_t i_code )
{
const uint8_t *p_peek;
int i_peek = stream_Peek( s, &p_peek, 14 );
if( i_peek < 4 )
return NULL;
int i_size = ps_pkt_size( p_peek, i_peek );
if( i_size <= 6 && p_peek[3] > 0xba )
{
/* Special case, search the next start code */
i_size = 6;
for( ;; )
{
i_peek = stream_Peek( s, &p_peek, i_size + 1024 );
if( i_peek <= i_size + 4 )
{
return NULL;
}
while( i_size <= i_peek - 4 )
{
if( p_peek[i_size] == 0x00 && p_peek[i_size+1] == 0x00 &&
p_peek[i_size+2] == 0x01 && p_peek[i_size+3] >= 0xb9 )
{
return stream_Block( s, i_size );
}
i_size++;
}
}
}
else
{
/* Normal case */
return stream_Block( s, i_size );
}
VLC_UNUSED(i_code);
return NULL;
}