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/*****************************************************************************
* asf.c: MMS access plug-in
*****************************************************************************
* Copyright (C) 2001-2004 VLC authors and VideoLAN
*
* 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.
*****************************************************************************/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <vlc_common.h>
#include <vlc_rand.h>
#include "asf.h"
#include "buffer.h"
#include "../../demux/asf/libasf_guid.h"
void GenerateGuid ( vlc_guid_t *p_guid )
{
p_guid->Data1 = 0xbabac001;
vlc_rand_bytes(&p_guid->Data2, sizeof(p_guid->Data2));
vlc_rand_bytes(&p_guid->Data3, sizeof(p_guid->Data3));
vlc_rand_bytes(p_guid->Data4, sizeof(p_guid->Data4));
}
void asf_HeaderParse ( asf_header_t *hdr,
uint8_t *p_header, int i_header )
{
var_buffer_t buffer;
vlc_guid_t guid;
uint64_t i_size;
hdr->i_file_size = 0;
hdr->i_data_packets_count = 0;
hdr->i_min_data_packet_size = 0;
for( unsigned i = 0; i < 128; i++ )
{
hdr->stream[i].i_cat = ASF_CODEC_TYPE_UNKNOWN;
hdr->stream[i].i_selected = 0;
hdr->stream[i].i_bitrate = -1;
}
var_buffer_initread( &buffer, p_header, i_header );
var_buffer_getguid( &buffer, &guid );
if( !guidcmp( &guid, &asf_object_header_guid ) )
{
/* ERROR: */
}
var_buffer_getmemory( &buffer, NULL, 30 - 16 );
for( ;; )
{
var_buffer_getguid( &buffer, &guid );
i_size = var_buffer_get64( &buffer );
if( guidcmp( &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( guidcmp( &guid, &asf_object_header_extension_guid ) )
{
/* Enter it */
var_buffer_getmemory( &buffer, NULL, 46 - 24 );
}
else if( guidcmp( &guid, &asf_object_extended_stream_properties_guid ) )
{
/* Grrrrrr */
int16_t i_count1, i_count2;
int i_subsize;
var_buffer_getmemory( &buffer, NULL, 84 - 24 );
i_count1 = var_buffer_get16( &buffer );
i_count2 = var_buffer_get16( &buffer );
i_subsize = 88;
for( int 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( int 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;
}
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( guidcmp( &guid, &asf_object_stream_properties_guid ) )
{
int i_stream_id;
vlc_guid_t stream_type;
var_buffer_getguid( &buffer, &stream_type );
var_buffer_getmemory( &buffer, NULL, 32 );
i_stream_id = var_buffer_get8( &buffer ) & 0x7f;
var_buffer_getmemory( &buffer, NULL, i_size - 24 - 32 - 16 - 1);
if( guidcmp( &stream_type, &asf_object_stream_type_video ) )
{
hdr->stream[i_stream_id].i_cat = ASF_CODEC_TYPE_VIDEO;
}
else if( guidcmp( &stream_type, &asf_object_stream_type_audio ) )
{
hdr->stream[i_stream_id].i_cat = ASF_CODEC_TYPE_AUDIO;
}
else
{
hdr->stream[i_stream_id].i_cat = ASF_CODEC_TYPE_UNKNOWN;
}
}
else if ( guidcmp( &guid, &asf_object_stream_bitrate_properties ) )
{
int i_count;
uint8_t i_stream_id;
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;
}
var_buffer_getmemory( &buffer, NULL, i_size - 24 );
}
else
{
// skip unknown guid
var_buffer_getmemory( &buffer, NULL, i_size - 24 );
}
if( var_buffer_readempty( &buffer ) )
return;
}
}
void asf_StreamSelect ( asf_header_t *hdr,
int i_bitrate_max,
bool b_all, bool b_audio, bool b_video )
{
/* XXX FIXME use mututal eclusion information */
unsigned 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_CODEC_TYPE_UNKNOWN )
{
hdr->stream[i].i_selected = 1;
}
}
return;
}
else
{
for( i = 0; i < 128; i++ )
{
/* by default, not selected */
hdr->stream[i].i_selected = 0;
}
}
/* 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_CODEC_TYPE_UNKNOWN )
{
continue;
}
else if( hdr->stream[i].i_cat == ASF_CODEC_TYPE_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_CODEC_TYPE_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;
}
}
}