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📄 asf.c

📁 video linux conference
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/***************************************************************************** * asf.c: MMS access plug-in ***************************************************************************** * Copyright (C) 2001-2004 VideoLAN * $Id: asf.c 10101 2005-03-02 16:47:31Z robux4 $ * * 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. *****************************************************************************/#include <stdlib.h>#include <vlc/vlc.h>#include "asf.h"#include "buffer.h"static int CmpGuid( const guid_t *p_guid1, const guid_t *p_guid2 ){    return( ( p_guid1->v1 == p_guid2->v1 &&              p_guid1->v2 == p_guid2->v2 &&              p_guid1->v3 == p_guid2->v3 &&              p_guid1->v4[0] == p_guid2->v4[0] &&              p_guid1->v4[1] == p_guid2->v4[1] &&              p_guid1->v4[2] == p_guid2->v4[2] &&              p_guid1->v4[3] == p_guid2->v4[3] &&              p_guid1->v4[4] == p_guid2->v4[4] &&              p_guid1->v4[5] == p_guid2->v4[5] &&              p_guid1->v4[6] == p_guid2->v4[6] &&              p_guid1->v4[7] == p_guid2->v4[7] ) ? 1 : 0 );}void E_( GenerateGuid )( guid_t *p_guid ){    int i;    srand( mdate() & 0xffffffff );    /* FIXME should be generated using random data */    p_guid->v1 = 0xbabac001;    p_guid->v2 = ( (uint64_t)rand() << 16 ) / RAND_MAX;    p_guid->v3 = ( (uint64_t)rand() << 16 ) / RAND_MAX;    for( i = 0; i < 8; i++ )    {        p_guid->v4[i] = ( (uint64_t)rand() * 256 ) / RAND_MAX;    }}void E_( asf_HeaderParse )( asf_header_t *hdr,                            uint8_t *p_header, int i_header ){    var_buffer_t buffer;    guid_t      guid;    uint64_t    i_size;    int         i;    hdr->i_file_size = 0;    hdr->i_data_packets_count = 0;    hdr->i_min_data_packet_size = 0;    for( i = 0; i < 128; i++ )    {        hdr->stream[i].i_cat = ASF_STREAM_UNKNOWN;        hdr->stream[i].i_selected = 0;        hdr->stream[i].i_bitrate = -1;    }    //fprintf( stderr, " ---------------------header:%d\n", i_header );    var_buffer_initread( &buffer, p_header, i_header );    var_buffer_getguid( &buffer, &guid );    if( !CmpGuid( &guid, &asf_object_header_guid ) )    {//        XXX Error//        fprintf( stderr, " ---------------------ERROR------\n" );    }    var_buffer_getmemory( &buffer, NULL, 30 - 16 );    for( ;; )    {        //fprintf( stderr, " ---------------------data:%d\n", buffer.i_data );        var_buffer_getguid( &buffer, &guid );        i_size = var_buffer_get64( &buffer );        //fprintf( stderr, "  guid=0x%8.8x-0x%4.4x-0x%4.4x-%2.2x%2.2x%2.2x%2.2x%2.2x%2.2x%2.2x%2.2x size=%lld\n",        //                  guid.v1,guid.v2, guid.v3,        //                  guid.v4[0],guid.v4[1],guid.v4[2],guid.v4[3],        //                  guid.v4[4],guid.v4[5],guid.v4[6],guid.v4[7],        //                  i_size );        if( CmpGuid( &guid, &asf_object_file_properties_guid ) )        {            var_buffer_getmemory( &buffer, NULL, 16 );            hdr->i_file_size            = var_buffer_get64( &buffer );            var_buffer_getmemory( &buffer, NULL, 8 );            hdr->i_data_packets_count   = var_buffer_get64( &buffer );            var_buffer_getmemory( &buffer, NULL, 8+8+8+4);            hdr->i_min_data_packet_size = var_buffer_get32( &buffer );            var_buffer_getmemory( &buffer, NULL, i_size - 24 - 16 - 8 - 8 - 8 - 8-8-8-4 - 4);        }        else if( CmpGuid( &guid, &asf_object_header_extension_guid ) )        {            /* Enter it */            var_buffer_getmemory( &buffer, NULL, 46 - 24 );        }        else if( CmpGuid( &guid, &asf_object_extended_stream_properties_guid ) )        {            /* Grrrrrr */            int16_t i_count1, i_count2;            int i_subsize;            int i;            //fprintf( stderr, "extended stream properties\n" );            var_buffer_getmemory( &buffer, NULL, 84 - 24 );            i_count1 = var_buffer_get16( &buffer );            i_count2 = var_buffer_get16( &buffer );            i_subsize = 88;            for( i = 0; i < i_count1; i++ )            {                int i_len;                var_buffer_get16( &buffer );                i_len = var_buffer_get16( &buffer );                var_buffer_getmemory( &buffer, NULL, i_len );                i_subsize = 4 + i_len;            }            for( i = 0; i < i_count2; i++ )            {                int i_len;                var_buffer_getmemory( &buffer, NULL, 16 + 2 );                i_len = var_buffer_get32( &buffer );                var_buffer_getmemory( &buffer, NULL, i_len );                i_subsize += 16 + 6 + i_len;            }            //fprintf( stderr, "extended stream properties left=%d\n",            //         i_size - i_subsize );            if( i_size - i_subsize <= 24 )            {                var_buffer_getmemory( &buffer, NULL, i_size - i_subsize );            }            /* It's a hack we just skip the first part of the object until             * the embed stream properties if any (ugly, but whose fault ?) */        }        else if( CmpGuid( &guid, &asf_object_stream_properties_guid ) )        {            int     i_stream_id;            guid_t  stream_type;            //fprintf( stderr, "stream properties\n" );            var_buffer_getguid( &buffer, &stream_type );            var_buffer_getmemory( &buffer, NULL, 32 );            i_stream_id = var_buffer_get8( &buffer ) & 0x7f;            //fprintf( stderr, " 1---------------------skip:%lld\n", i_size - 24 - 32 - 16 - 1 );            var_buffer_getmemory( &buffer, NULL, i_size - 24 - 32 - 16 - 1);            if( CmpGuid( &stream_type, &asf_object_stream_type_video ) )            {                //fprintf( stderr, "\nvideo stream[%d] found\n", i_stream_id );                hdr->stream[i_stream_id].i_cat = ASF_STREAM_VIDEO;            }            else if( CmpGuid( &stream_type, &asf_object_stream_type_audio ) )            {                //fprintf( stderr, "\naudio stream[%d] found\n", i_stream_id );                hdr->stream[i_stream_id].i_cat = ASF_STREAM_AUDIO;            }            else            {                hdr->stream[i_stream_id].i_cat = ASF_STREAM_UNKNOWN;            }        }        else if ( CmpGuid( &guid, &asf_object_bitrate_properties_guid ) )        {            int     i_count;            uint8_t i_stream_id;            //fprintf( stderr, "bitrate properties\n" );            i_count = var_buffer_get16( &buffer );            i_size -= 2;            while( i_count > 0 )            {                i_stream_id = var_buffer_get16( &buffer )&0x7f;                hdr->stream[i_stream_id].i_bitrate =  var_buffer_get32( &buffer );                i_count--;                i_size -= 6;            }            //fprintf( stderr, " 2---------------------skip:%lld\n", i_size - 24);            var_buffer_getmemory( &buffer, NULL, i_size - 24 );        }        else        {            //fprintf( stderr, "unknown\n" );            //fprintf( stderr, " 3---------------------skip:%lld\n", i_size - 24);            // skip unknown guid            var_buffer_getmemory( &buffer, NULL, i_size - 24 );        }        if( var_buffer_readempty( &buffer ) )            return;    }}void E_( asf_StreamSelect ) ( asf_header_t *hdr,                              int i_bitrate_max,                              vlc_bool_t b_all, vlc_bool_t b_audio, vlc_bool_t b_video ){    /* XXX FIXME use mututal eclusion information */    int i;    int i_audio, i_video;    int i_bitrate_total;#if 0    char *psz_stream;#endif    i_audio = 0;    i_video = 0;    i_bitrate_total = 0;    if( b_all )    {        /* select all valid stream */        for( i = 1; i < 128; i++ )        {            if( hdr->stream[i].i_cat != ASF_STREAM_UNKNOWN )            {                hdr->stream[i].i_selected = 1;            }        }        return;    }    else    {        for( i = 0; i < 128; i++ )        {            hdr->stream[i].i_selected = 0; /* by default, not selected */        }    }    /* big test:     * select a stream if     *    - no audio nor video stream     *    - or:     *         - if i_bitrate_max not set keep the highest bitrate     *         - if i_bitrate_max is set, keep stream that make we used best     *           quality regarding i_bitrate_max     *     * XXX: little buggy:     *        - it doesn't use mutual exclusion info..     *        - when selecting a better stream we could select     *        something that make i_bitrate_total> i_bitrate_max     */    for( i = 1; i < 128; i++ )    {        if( hdr->stream[i].i_cat == ASF_STREAM_UNKNOWN )        {            continue;        }        else if( hdr->stream[i].i_cat == ASF_STREAM_AUDIO && b_audio &&                 ( i_audio <= 0 ||                    ( ( ( hdr->stream[i].i_bitrate > hdr->stream[i_audio].i_bitrate &&                          ( i_bitrate_total + hdr->stream[i].i_bitrate - hdr->stream[i_audio].i_bitrate                                            < i_bitrate_max || !i_bitrate_max) ) ||                        ( hdr->stream[i].i_bitrate < hdr->stream[i_audio].i_bitrate &&                              i_bitrate_max != 0 && i_bitrate_total > i_bitrate_max )                      ) )  ) )        {            /* unselect old stream */            if( i_audio > 0 )            {                hdr->stream[i_audio].i_selected = 0;                if( hdr->stream[i_audio].i_bitrate> 0 )                {                    i_bitrate_total -= hdr->stream[i_audio].i_bitrate;                }            }            hdr->stream[i].i_selected = 1;            if( hdr->stream[i].i_bitrate> 0 )            {                i_bitrate_total += hdr->stream[i].i_bitrate;            }            i_audio = i;        }        else if( hdr->stream[i].i_cat == ASF_STREAM_VIDEO && b_video &&                 ( i_video <= 0 ||                    (                        ( ( hdr->stream[i].i_bitrate > hdr->stream[i_video].i_bitrate &&                            ( i_bitrate_total + hdr->stream[i].i_bitrate - hdr->stream[i_video].i_bitrate                                            < i_bitrate_max || !i_bitrate_max) ) ||                          ( hdr->stream[i].i_bitrate < hdr->stream[i_video].i_bitrate &&                            i_bitrate_max != 0 && i_bitrate_total > i_bitrate_max )                        ) ) )  )        {            /* unselect old stream */            if( i_video > 0 )            {                hdr->stream[i_video].i_selected = 0;                if( hdr->stream[i_video].i_bitrate> 0 )                {                    i_bitrate_total -= hdr->stream[i_video].i_bitrate;                }            }            hdr->stream[i].i_selected = 1;            if( hdr->stream[i].i_bitrate> 0 )            {                i_bitrate_total += hdr->stream[i].i_bitrate;            }            i_video = i;        }    }}

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