demux.c 16.6 KB
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/*****************************************************************************
 * demux.c: demuxer using ffmpeg (libavformat).
 *****************************************************************************
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 * Copyright (C) 2004-2007 the VideoLAN team
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 * $Id$
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 *
 * Authors: Laurent Aimar <fenrir@via.ecp.fr>
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 *          Gildas Bazin <gbazin@videolan.org>
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 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; 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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 *****************************************************************************/

/*****************************************************************************
 * Preamble
 *****************************************************************************/

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#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

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#include <vlc/vlc.h>
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#include <vlc_demux.h>
#include <vlc_stream.h>
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#include <vlc_meta.h>
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/* ffmpeg header */
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#if defined(HAVE_LIBAVFORMAT_AVFORMAT_H)
#   include <libavformat/avformat.h>
#elif defined(HAVE_FFMPEG_AVFORMAT_H)
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#   include <ffmpeg/avformat.h>
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#elif defined(HAVE_LIBAVFORMAT_TREE)
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#   include <avformat.h>
#endif

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#include "ffmpeg.h"

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//#define AVFORMAT_DEBUG 1

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/* Version checking */
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#if defined(HAVE_FFMPEG_AVFORMAT_H) || defined(HAVE_LIBAVFORMAT_AVFORMAT_H) || defined(HAVE_LIBAVFORMAT_TREE)
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/*****************************************************************************
 * demux_sys_t: demux descriptor
 *****************************************************************************/
struct demux_sys_t
{
    ByteIOContext   io;
    int             io_buffer_size;
    uint8_t        *io_buffer;

    AVInputFormat  *fmt;
    AVFormatContext *ic;
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    URLContext     url;
    URLProtocol    prot;
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    int             i_tk;
    es_out_id_t     **tk;

    int64_t     i_pcr;
    int64_t     i_pcr_inc;
    int         i_pcr_tk;
};

/*****************************************************************************
 * Local prototypes
 *****************************************************************************/
static int Demux  ( demux_t *p_demux );
static int Control( demux_t *p_demux, int i_query, va_list args );

static int IORead( void *opaque, uint8_t *buf, int buf_size );
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static offset_t IOSeek( void *opaque, offset_t offset, int whence );
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/*****************************************************************************
 * Open
 *****************************************************************************/
int E_(OpenDemux)( vlc_object_t *p_this )
{
    demux_t       *p_demux = (demux_t*)p_this;
    demux_sys_t   *p_sys;
    AVProbeData   pd;
    AVInputFormat *fmt;
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    int i;
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    vlc_bool_t b_avfmt_nofile;
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    /* Init Probe data */
    pd.filename = p_demux->psz_path;
    if( ( pd.buf_size = stream_Peek( p_demux->s, &pd.buf, 2048 ) ) <= 0 )
    {
        msg_Warn( p_demux, "cannot peek" );
        return VLC_EGENERIC;
    }

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    av_register_all(); /* Can be called several times */
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    /* Guess format */
    if( !( fmt = av_probe_input_format( &pd, 1 ) ) )
    {
        msg_Dbg( p_demux, "couldn't guess format" );
        return VLC_EGENERIC;
    }

    /* Don't try to handle MPEG unless forced */
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    if( !p_demux->b_force &&
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        ( !strcmp( fmt->name, "mpeg" ) ||
          !strcmp( fmt->name, "vcd" ) ||
          !strcmp( fmt->name, "vob" ) ||
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          !strcmp( fmt->name, "mpegts" ) ||
          /* libavformat's redirector won't work */
          !strcmp( fmt->name, "redir" ) ||
          !strcmp( fmt->name, "sdp" ) ) )
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    {
        return VLC_EGENERIC;
    }

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    /* Don't trigger false alarms on bin files */
    if( !p_demux->b_force && !strcmp( fmt->name, "psxstr" ) )
    {
        int i_len;

        if( !p_demux->psz_path ) return VLC_EGENERIC;

        i_len = strlen( p_demux->psz_path );
        if( i_len < 4 ) return VLC_EGENERIC;

        if( strcasecmp( &p_demux->psz_path[i_len - 4], ".str" ) &&
            strcasecmp( &p_demux->psz_path[i_len - 4], ".xai" ) &&
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            strcasecmp( &p_demux->psz_path[i_len - 3], ".xa" ) )
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        {
            return VLC_EGENERIC;
        }
    }

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    msg_Dbg( p_demux, "detected format: %s", fmt->name );

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    /* Fill p_demux fields */
    p_demux->pf_demux = Demux;
    p_demux->pf_control = Control;
    p_demux->p_sys = p_sys = malloc( sizeof( demux_sys_t ) );
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    p_sys->ic = 0;
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    p_sys->fmt = fmt;
    p_sys->i_tk = 0;
    p_sys->tk = NULL;
    p_sys->i_pcr_tk = -1;
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    p_sys->i_pcr = -1;
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    /* Create I/O wrapper */
    p_sys->io_buffer_size = 32768;  /* FIXME */
    p_sys->io_buffer = malloc( p_sys->io_buffer_size );
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    p_sys->url.priv_data = p_demux;
    p_sys->url.prot = &p_sys->prot;
    p_sys->url.prot->name = "VLC I/O wrapper";
    p_sys->url.prot->url_open = 0;
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    p_sys->url.prot->url_read =
                    (int (*) (URLContext *, unsigned char *, int))IORead;
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    p_sys->url.prot->url_write = 0;
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    p_sys->url.prot->url_seek =
                    (offset_t (*) (URLContext *, offset_t, int))IOSeek;
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    p_sys->url.prot->url_close = 0;
    p_sys->url.prot->next = 0;
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    init_put_byte( &p_sys->io, p_sys->io_buffer, p_sys->io_buffer_size,
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                   0, &p_sys->url, IORead, NULL, IOSeek );
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    b_avfmt_nofile = p_sys->fmt->flags & AVFMT_NOFILE;
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    p_sys->fmt->flags |= AVFMT_NOFILE; /* libavformat must not fopen/fclose */

    /* Open it */
    if( av_open_input_stream( &p_sys->ic, &p_sys->io, p_demux->psz_path,
                              p_sys->fmt, NULL ) )
    {
        msg_Err( p_demux, "av_open_input_stream failed" );
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        if( !b_avfmt_nofile ) p_sys->fmt->flags ^= AVFMT_NOFILE;
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        E_(CloseDemux)( p_this );
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        return VLC_EGENERIC;
    }

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    if( av_find_stream_info( p_sys->ic ) < 0 )
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    {
        msg_Err( p_demux, "av_find_stream_info failed" );
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        if( !b_avfmt_nofile ) p_sys->fmt->flags ^= AVFMT_NOFILE;
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        E_(CloseDemux)( p_this );
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        return VLC_EGENERIC;
    }
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    if( !b_avfmt_nofile ) p_sys->fmt->flags ^= AVFMT_NOFILE;
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    for( i = 0; i < p_sys->ic->nb_streams; i++ )
    {
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        AVCodecContext *cc = p_sys->ic->streams[i]->codec;
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        es_out_id_t  *es;
        es_format_t  fmt;
        vlc_fourcc_t fcc;

        if( !E_(GetVlcFourcc)( cc->codec_id, NULL, &fcc, NULL ) )
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        {
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            fcc = VLC_FOURCC( 'u', 'n', 'd', 'f' );

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            /* Special case for raw video data */
            if( cc->codec_id == CODEC_ID_RAWVIDEO )
            {
                msg_Dbg( p_demux, "raw video, pixel format: %i", cc->pix_fmt );
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                fcc = E_(GetVlcChroma)( cc->pix_fmt );
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            }
        }

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        switch( cc->codec_type )
        {
        case CODEC_TYPE_AUDIO:
            es_format_Init( &fmt, AUDIO_ES, fcc );
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            fmt.audio.i_channels = cc->channels;
            fmt.audio.i_rate = cc->sample_rate;
            fmt.audio.i_bitspersample = cc->bits_per_sample;
            fmt.audio.i_blockalign = cc->block_align;
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            break;
        case CODEC_TYPE_VIDEO:
            es_format_Init( &fmt, VIDEO_ES, fcc );
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            fmt.video.i_width = cc->width;
            fmt.video.i_height = cc->height;
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            if( cc->palctrl )
            {
                fmt.video.p_palette = malloc( sizeof(video_palette_t) );
                *fmt.video.p_palette = *(video_palette_t *)cc->palctrl;
            }
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            break;
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        case CODEC_TYPE_SUBTITLE:
            es_format_Init( &fmt, SPU_ES, fcc );
            break;
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        default:
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            msg_Warn( p_demux, "unsupported track type in ffmpeg demux" );
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            break;
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        }

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        fmt.psz_language = strdup( p_sys->ic->streams[i]->language );
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        fmt.i_extra = cc->extradata_size;
        fmt.p_extra = cc->extradata;
        es = es_out_Add( p_demux->out, &fmt );

        msg_Dbg( p_demux, "adding es: %s codec = %4.4s",
                 cc->codec_type == CODEC_TYPE_AUDIO ? "audio" : "video",
                 (char*)&fcc );
        TAB_APPEND( p_sys->i_tk, p_sys->tk, es );
    }

    msg_Dbg( p_demux, "AVFormat supported stream" );
    msg_Dbg( p_demux, "    - format = %s (%s)",
             p_sys->fmt->name, p_sys->fmt->long_name );
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    msg_Dbg( p_demux, "    - start time = "I64Fd,
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             ( p_sys->ic->start_time != (int64_t)AV_NOPTS_VALUE ) ?
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             p_sys->ic->start_time * 1000000 / AV_TIME_BASE : -1 );
    msg_Dbg( p_demux, "    - duration = "I64Fd,
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             ( p_sys->ic->duration != (int64_t)AV_NOPTS_VALUE ) ?
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             p_sys->ic->duration * 1000000 / AV_TIME_BASE : -1 );
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    return VLC_SUCCESS;
}

/*****************************************************************************
 * Close
 *****************************************************************************/
void E_(CloseDemux)( vlc_object_t *p_this )
{
    demux_t     *p_demux = (demux_t*)p_this;
    demux_sys_t *p_sys = p_demux->p_sys;
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    vlc_bool_t b_avfmt_nofile;
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    FREENULL( p_sys->tk );
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    b_avfmt_nofile = p_sys->fmt->flags & AVFMT_NOFILE;
    p_sys->fmt->flags |= AVFMT_NOFILE; /* libavformat must not fopen/fclose */
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    if( p_sys->ic ) av_close_input_file( p_sys->ic );
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    if( !b_avfmt_nofile ) p_sys->fmt->flags ^= AVFMT_NOFILE;

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    if( p_sys->io_buffer ) free( p_sys->io_buffer );
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    free( p_sys );
}

/*****************************************************************************
 * Demux:
 *****************************************************************************/
static int Demux( demux_t *p_demux )
{
    demux_sys_t *p_sys = p_demux->p_sys;
    AVPacket    pkt;
    block_t     *p_frame;
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    int64_t     i_start_time;
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    /* Read a frame */
    if( av_read_frame( p_sys->ic, &pkt ) )
    {
        return 0;
    }
    if( pkt.stream_index < 0 || pkt.stream_index >= p_sys->i_tk )
    {
        av_free_packet( &pkt );
        return 1;
    }
    if( ( p_frame = block_New( p_demux, pkt.size ) ) == NULL )
    {
        return 0;
    }

    memcpy( p_frame->p_buffer, pkt.data, pkt.size );
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    i_start_time = ( p_sys->ic->start_time != (int64_t)AV_NOPTS_VALUE ) ?
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        ( p_sys->ic->start_time / AV_TIME_BASE )  : 0;
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    p_frame->i_dts = ( pkt.dts == (int64_t)AV_NOPTS_VALUE ) ?
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        0 : (pkt.dts - i_start_time) * 1000000 *
        p_sys->ic->streams[pkt.stream_index]->time_base.num /
        p_sys->ic->streams[pkt.stream_index]->time_base.den;
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    p_frame->i_pts = ( pkt.pts == (int64_t)AV_NOPTS_VALUE ) ?
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        0 : (pkt.pts - i_start_time) * 1000000 *
        p_sys->ic->streams[pkt.stream_index]->time_base.num /
        p_sys->ic->streams[pkt.stream_index]->time_base.den;
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#ifdef AVFORMAT_DEBUG
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    msg_Dbg( p_demux, "tk[%d] dts="I64Fd" pts="I64Fd,
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             pkt.stream_index, p_frame->i_dts, p_frame->i_pts );
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#endif
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    if( pkt.dts > 0  &&
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        ( pkt.stream_index == p_sys->i_pcr_tk || p_sys->i_pcr_tk < 0 ) )
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    {
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        p_sys->i_pcr_tk = pkt.stream_index;
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        p_sys->i_pcr = p_frame->i_dts;
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        es_out_Control( p_demux->out, ES_OUT_SET_PCR, (int64_t)p_sys->i_pcr );
    }

    es_out_Send( p_demux->out, p_sys->tk[pkt.stream_index], p_frame );
    av_free_packet( &pkt );
    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:
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            pf = (double*) va_arg( args, double* ); *pf = 0.0;
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            i64 = stream_Size( p_demux->s );
            if( i64 > 0 )
            {
                *pf = (double)stream_Tell( p_demux->s ) / (double)i64;
            }
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            if( (p_sys->ic->duration != (int64_t)AV_NOPTS_VALUE) && (p_sys->i_pcr > 0) )
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            {
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                *pf = (double)p_sys->i_pcr / (double)p_sys->ic->duration;
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            }
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            return VLC_SUCCESS;

        case DEMUX_SET_POSITION:
            f = (double) va_arg( args, double );
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            i64 = stream_Tell( p_demux->s );
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            if( p_sys->i_pcr > 0 )
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            {
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                i64 = p_sys->ic->duration * f;
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                if( p_sys->ic->start_time != (int64_t)AV_NOPTS_VALUE )
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                    i64 += p_sys->ic->start_time;

                msg_Warn( p_demux, "DEMUX_SET_POSITION: "I64Fd, i64 );

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                /* If we have a duration, we prefer to seek by time
                   but if we don't, or if the seek fails, try BYTE seeking */
                if( p_sys->ic->duration == (int64_t)AV_NOPTS_VALUE ||
                    (av_seek_frame( p_sys->ic, -1, i64, 0 ) < 0) )
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                {
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                    int64_t i_size = stream_Size( p_demux->s );
                    i64 = (int64_t)i_size * f;

                    msg_Warn( p_demux, "DEMUX_SET_BYTE_POSITION: "I64Fd, i64 );
                    if( av_seek_frame( p_sys->ic, -1, i64, AVSEEK_FLAG_BYTE ) < 0 )
                        return VLC_EGENERIC;
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                }
                es_out_Control( p_demux->out, ES_OUT_RESET_PCR );
                p_sys->i_pcr = -1; /* Invalidate time display */
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            }
            return VLC_SUCCESS;

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        case DEMUX_GET_LENGTH:
            pi64 = (int64_t*)va_arg( args, int64_t * );
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            if( p_sys->ic->duration != (int64_t)AV_NOPTS_VALUE )
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            {
                *pi64 = p_sys->ic->duration;
            }
            else *pi64 = 0;
            return VLC_SUCCESS;

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        case DEMUX_GET_TIME:
            pi64 = (int64_t*)va_arg( args, int64_t * );
            *pi64 = p_sys->i_pcr;
            return VLC_SUCCESS;

        case DEMUX_SET_TIME:
            i64 = (int64_t)va_arg( args, int64_t );
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            if( p_sys->ic->start_time != (int64_t)AV_NOPTS_VALUE )
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                i64 += p_sys->ic->start_time;

            msg_Warn( p_demux, "DEMUX_SET_TIME: "I64Fd, i64 );

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            if( av_seek_frame( p_sys->ic, -1, i64, 0 ) < 0 )
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            {
                return VLC_EGENERIC;
            }
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            es_out_Control( p_demux->out, ES_OUT_RESET_PCR );
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            p_sys->i_pcr = -1; /* Invalidate time display */
            return VLC_SUCCESS;

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        case DEMUX_GET_META:
        {
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            vlc_meta_t *p_meta = (vlc_meta_t*)va_arg( args, vlc_meta_t* );
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            if( !p_sys->ic->title[0] || !p_sys->ic->author[0] ||
                !p_sys->ic->copyright[0] || !p_sys->ic->comment[0] ||
                /*!p_sys->ic->album[0] ||*/ !p_sys->ic->genre[0] )
            {
                return VLC_EGENERIC;
            }

            if( p_sys->ic->title[0] )
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                vlc_meta_SetTitle( p_meta, p_sys->ic->title );
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            if( p_sys->ic->author[0] )
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                vlc_meta_SetArtist( p_meta, p_sys->ic->author );
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            if( p_sys->ic->copyright[0] )
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                vlc_meta_SetCopyright( p_meta, p_sys->ic->copyright );
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            if( p_sys->ic->comment[0] )
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                vlc_meta_SetDescription( p_meta, p_sys->ic->comment );
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            if( p_sys->ic->genre[0] )
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                vlc_meta_SetGenre( p_meta, p_sys->ic->genre );
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            return VLC_SUCCESS;
        }

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        default:
            return VLC_EGENERIC;
    }
}

/*****************************************************************************
 * I/O wrappers for libavformat
 *****************************************************************************/
static int IORead( void *opaque, uint8_t *buf, int buf_size )
{
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    URLContext *p_url = opaque;
    demux_t *p_demux = p_url->priv_data;
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    int i_ret = stream_Read( p_demux->s, buf, buf_size );
    return i_ret ? i_ret : -1;
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}

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static offset_t IOSeek( void *opaque, offset_t offset, int whence )
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{
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    URLContext *p_url = opaque;
    demux_t *p_demux = p_url->priv_data;
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    int64_t i_absolute = (int64_t)offset;
    int64_t i_size = stream_Size( p_demux->s );
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#ifdef AVFORMAT_DEBUG
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    msg_Warn( p_demux, "IOSeek offset: "I64Fd", whence: %i", offset, whence );
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#endif
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    switch( whence )
    {
        case SEEK_SET:
            break;
        case SEEK_CUR:
            i_absolute = stream_Tell( p_demux->s ) + offset;
            break;
        case SEEK_END:
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            i_absolute = i_size + offset;
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            break;
        default:
            return -1;

    }
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    if( i_absolute < 0 )
        i_absolute = 0;
    if( i_size && i_absolute > i_size )
        i_absolute = i_size;
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    if( stream_Seek( p_demux->s, i_absolute ) )
    {
        return -1;
    }

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    return stream_Tell( p_demux->s );
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}

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#endif /* HAVE_LIBAVFORMAT_AVFORMAT_H */