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📄 asf.c

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/***************************************************************************** * asf.c : ASF demux module ***************************************************************************** * Copyright (C) 2002-2003 VideoLAN * $Id: asf.c 10150 2005-03-05 17:54:19Z gbazin $ * * 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 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 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA. *****************************************************************************//***************************************************************************** * Preamble *****************************************************************************/#include <stdlib.h>                                      /* malloc(), free() */#include <vlc/vlc.h>#include <vlc/input.h>#include "vlc_meta.h"#include "codecs.h"                        /* BITMAPINFOHEADER, WAVEFORMATEX */#include "libasf.h"/* TODO *  - add support for the newly added object: language, bitrate, *                                            extended stream properties. *//***************************************************************************** * Module descriptor *****************************************************************************/static int  Open  ( vlc_object_t * );static void Close ( vlc_object_t * );vlc_module_begin();    set_category( CAT_INPUT );    set_subcategory( SUBCAT_INPUT_DEMUX );    set_description( _("ASF v1.0 demuxer") );    set_capability( "demux2", 200 );    set_callbacks( Open, Close );    add_shortcut( "asf" );vlc_module_end();/***************************************************************************** * Local prototypes *****************************************************************************/static int Demux  ( demux_t * );static int Control( demux_t *, int i_query, va_list args );typedef struct{    int i_cat;    es_out_id_t     *p_es;    asf_object_stream_properties_t *p_sp;    mtime_t i_time;    block_t         *p_frame; /* use to gather complete frame */} asf_track_t;struct demux_sys_t{    mtime_t             i_time;     /* 祍 */    mtime_t             i_length;   /* length of file file */    int64_t             i_bitrate;  /* global file bitrate */    asf_object_root_t            *p_root;    asf_object_file_properties_t *p_fp;    unsigned int        i_track;    asf_track_t         *track[128];    int64_t             i_data_begin;    int64_t             i_data_end;    vlc_meta_t          *meta;};static mtime_t  GetMoviePTS( demux_sys_t * );static int      DemuxInit( demux_t * );static void     DemuxEnd( demux_t * );static int      DemuxPacket( demux_t * );/***************************************************************************** * Open: check file and initializes ASF structures *****************************************************************************/static int Open( vlc_object_t * p_this ){    demux_t     *p_demux = (demux_t *)p_this;    demux_sys_t *p_sys;    guid_t      guid;    uint8_t     *p_peek;    /* A little test to see if it could be a asf stream */    if( stream_Peek( p_demux->s, &p_peek, 16 ) < 16 ) return VLC_EGENERIC;    ASF_GetGUID( &guid, p_peek );    if( !ASF_CmpGUID( &guid, &asf_object_header_guid ) ) return VLC_EGENERIC;    /* Set p_demux fields */    p_demux->pf_demux = Demux;    p_demux->pf_control = Control;    p_demux->p_sys = p_sys = malloc( sizeof( demux_sys_t ) );    memset( p_sys, 0, sizeof( demux_sys_t ) );    /* Load the headers */    if( DemuxInit( p_demux ) )    {        return VLC_EGENERIC;    }    return VLC_SUCCESS;}/***************************************************************************** * Demux: read packet and send them to decoders *****************************************************************************/static int Demux( demux_t *p_demux ){    demux_sys_t *p_sys = p_demux->p_sys;    for( ;; )    {        uint8_t *p_peek;        mtime_t i_length;        mtime_t i_time_begin = GetMoviePTS( p_sys );        int i_result;        if( p_demux->b_die )        {            break;        }        /* Check if we have concatenated files */        if( stream_Peek( p_demux->s, &p_peek, 16 ) == 16 )        {            guid_t guid;            ASF_GetGUID( &guid, p_peek );            if( ASF_CmpGUID( &guid, &asf_object_header_guid ) )            {                msg_Warn( p_demux, "Found a new ASF header" );                /* We end this stream */                DemuxEnd( p_demux );                /* And we prepare to read the next one */                if( DemuxInit( p_demux ) )                {                    msg_Err( p_demux, "failed to load the new header" );                    return 0;                }                continue;            }        }        /* Read and demux a packet */        if( ( i_result = DemuxPacket( p_demux ) ) <= 0 )        {            return i_result;        }        if( i_time_begin == -1 )        {            i_time_begin = GetMoviePTS( p_sys );        }        else        {            i_length = GetMoviePTS( p_sys ) - i_time_begin;            if( i_length < 0 || i_length >= 40 * 1000 )            {                break;            }        }    }    /* Set the PCR */    p_sys->i_time = GetMoviePTS( p_sys );    if( p_sys->i_time >= 0 )    {        es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_sys->i_time );    }    return 1;}/***************************************************************************** * Close: frees unused data *****************************************************************************/static void Close( vlc_object_t * p_this ){    demux_t     *p_demux = (demux_t *)p_this;    DemuxEnd( p_demux );    free( p_demux->p_sys );}/***************************************************************************** * Control: *****************************************************************************/static int Control( demux_t *p_demux, int i_query, va_list args ){    demux_sys_t *p_sys = p_demux->p_sys;    int64_t     *pi64;    int         i;    vlc_meta_t **pp_meta;    switch( i_query )    {        case DEMUX_SET_TIME:            return VLC_EGENERIC;        case DEMUX_GET_LENGTH:            pi64 = (int64_t*)va_arg( args, int64_t * );            *pi64 = p_sys->i_length;            return VLC_SUCCESS;        case DEMUX_GET_META:            pp_meta = (vlc_meta_t**)va_arg( args, vlc_meta_t** );            *pp_meta = vlc_meta_Duplicate( p_sys->meta );            return VLC_SUCCESS;        case DEMUX_SET_POSITION:            p_sys->i_time = -1;            for( i = 0; i < 128 ; i++ )            {                asf_track_t *tk = p_sys->track[i];                if( tk ) tk->i_time = -1;            }        default:            return demux2_vaControlHelper( p_demux->s,                                           p_sys->i_data_begin, p_sys->i_data_end,                                           p_sys->i_bitrate, p_sys->p_fp->i_min_data_packet_size,                                           i_query, args );    }}/***************************************************************************** * *****************************************************************************/static mtime_t GetMoviePTS( demux_sys_t *p_sys ){    mtime_t i_time;    int     i;    i_time = -1;    for( i = 0; i < 128 ; i++ )    {        asf_track_t *tk = p_sys->track[i];        if( tk && tk->p_es && tk->i_time > 0)        {            if( i_time < 0 )            {                i_time = tk->i_time;            }            else            {                i_time = __MIN( i_time, tk->i_time );            }        }    }    return i_time;}#define GETVALUE2b( bits, var, def ) \    switch( (bits)&0x03 ) \    { \        case 1: var = p_peek[i_skip]; i_skip++; break; \        case 2: var = GetWLE( p_peek + i_skip );  i_skip+= 2; break; \        case 3: var = GetDWLE( p_peek + i_skip ); i_skip+= 4; break; \        case 0: \        default: var = def; break;\    }static int DemuxPacket( demux_t *p_demux ){    demux_sys_t *p_sys = p_demux->p_sys;    int         i_data_packet_min = p_sys->p_fp->i_min_data_packet_size;    uint8_t     *p_peek;    int         i_skip;    int         i_packet_size_left;    int         i_packet_flags;    int         i_packet_property;    int         b_packet_multiple_payload;    int         i_packet_length;    int         i_packet_sequence;    int         i_packet_padding_length;    uint32_t    i_packet_send_time;    uint16_t    i_packet_duration;    int         i_payload;    int         i_payload_count;    int         i_payload_length_type;    if( stream_Peek( p_demux->s, &p_peek,i_data_packet_min)<i_data_packet_min )    {        msg_Warn( p_demux, "cannot peek while getting new packet, EOF ?" );        return 0;    }    i_skip = 0;    /* *** parse error correction if present *** */    if( p_peek[0]&0x80 )    {        unsigned int i_error_correction_length_type;        unsigned int i_error_correction_data_length;        unsigned int i_opaque_data_present;        i_error_correction_data_length = p_peek[0] & 0x0f;  // 4bits        i_opaque_data_present = ( p_peek[0] >> 4 )& 0x01;    // 1bit        i_error_correction_length_type = ( p_peek[0] >> 5 ) & 0x03; // 2bits        i_skip += 1; // skip error correction flags        if( i_error_correction_length_type != 0x00 ||            i_opaque_data_present != 0 ||            i_error_correction_data_length != 0x02 )        {            goto loop_error_recovery;        }        i_skip += i_error_correction_data_length;    }    else    {        msg_Warn( p_demux, "p_peek[0]&0x80 != 0x80" );    }    /* sanity check */    if( i_skip + 2 >= i_data_packet_min )    {        goto loop_error_recovery;    }    i_packet_flags = p_peek[i_skip]; i_skip++;    i_packet_property = p_peek[i_skip]; i_skip++;    b_packet_multiple_payload = i_packet_flags&0x01;    /* read some value */    GETVALUE2b( i_packet_flags >> 5, i_packet_length, i_data_packet_min );    GETVALUE2b( i_packet_flags >> 1, i_packet_sequence, 0 );    GETVALUE2b( i_packet_flags >> 3, i_packet_padding_length, 0 );    i_packet_send_time = GetDWLE( p_peek + i_skip ); i_skip += 4;    i_packet_duration  = GetWLE( p_peek + i_skip ); i_skip += 2;//        i_packet_size_left = i_packet_length;   // XXX donn閑s reellement lu    /* FIXME I have to do that for some file, I don't known why */    i_packet_size_left = i_data_packet_min;    if( b_packet_multiple_payload )    {        i_payload_count = p_peek[i_skip] & 0x3f;        i_payload_length_type = ( p_peek[i_skip] >> 6 )&0x03;        i_skip++;    }    else    {        i_payload_count = 1;        i_payload_length_type = 0x02; // unused    }    for( i_payload = 0; i_payload < i_payload_count ; i_payload++ )    {        asf_track_t   *tk;        int i_stream_number;        int i_media_object_number;        int i_media_object_offset;        int i_replicated_data_length;        int i_payload_data_length;        int i_payload_data_pos;        int i_sub_payload_data_length;        int i_tmp;        mtime_t i_pts;        mtime_t i_pts_delta;        if( i_skip >= i_packet_size_left )        {            /* prevent some segfault with invalid file */            break;        }        i_stream_number = p_peek[i_skip] & 0x7f;        i_skip++;        GETVALUE2b( i_packet_property >> 4, i_media_object_number, 0 );        GETVALUE2b( i_packet_property >> 2, i_tmp, 0 );        GETVALUE2b( i_packet_property, i_replicated_data_length, 0 );        if( i_replicated_data_length > 1 ) // should be at least 8 bytes        {            i_pts = (mtime_t)GetDWLE( p_peek + i_skip + 4 ) * 1000;            i_skip += i_replicated_data_length;            i_pts_delta = 0;            i_media_object_offset = i_tmp;            if( i_skip >= i_packet_size_left )            {                break;            }        }        else if( i_replicated_data_length == 1 )        {            /* msg_Dbg( p_demux, "found compressed payload" ); */            i_pts = (mtime_t)i_tmp * 1000;            i_pts_delta = (mtime_t)p_peek[i_skip] * 1000; i_skip++;            i_media_object_offset = 0;        }        else        {            i_pts = (mtime_t)i_packet_send_time * 1000;            i_pts_delta = 0;            i_media_object_offset = i_tmp;        }        i_pts = __MAX( i_pts - p_sys->p_fp->i_preroll * 1000, 0 );        if( b_packet_multiple_payload )        {            GETVALUE2b( i_payload_length_type, i_payload_data_length, 0 );        }        else        {            i_payload_data_length = i_packet_length -                                        i_packet_padding_length - i_skip;        }

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