mirror of
https://code.videolan.org/videolan/vlc
synced 2024-10-07 03:56:28 +02:00
19ea8feb6d
waveout, directx, qnx, beos, win32, macosx, and the AltiVec modules.
* ALL: removed mention of AC3 in favour of A52.
* ./configure.in, ./Makefile*: modules can now be built deeper than 1
directory. As a consequence, the build is even slower (but I'm fixing
this) and make clean doesn't work anymore.
130 lines
4.0 KiB
C
130 lines
4.0 KiB
C
/*****************************************************************************
|
|
* decoder.c: core A52 decoder
|
|
*****************************************************************************
|
|
* Copyright (C) 1999-2001 VideoLAN
|
|
* $Id: decoder.c,v 1.1 2002/08/04 17:23:42 sam Exp $
|
|
*
|
|
* Authors: Michel Kaempf <maxx@via.ecp.fr>
|
|
* Michel Lespinasse <walken@zoy.org>
|
|
* Aaron Holtzman <aholtzma@engr.uvic.ca>
|
|
*
|
|
* 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 <string.h> /* memcpy() */
|
|
|
|
#include <vlc/vlc.h>
|
|
#include <vlc/decoder.h>
|
|
|
|
#include "imdct.h"
|
|
#include "downmix.h"
|
|
#include "adec.h" /* a52dec_thread_t */
|
|
|
|
#include "internal.h"
|
|
|
|
static const float cmixlev_lut[4] = { 0.707, 0.595, 0.500, 0.707 };
|
|
static const float smixlev_lut[4] = { 0.707, 0.500, 0.0 , 0.500 };
|
|
|
|
int E_( a52_init )(a52dec_t * p_a52dec)
|
|
{
|
|
p_a52dec->mantissa.lfsr_state = 1; /* dither_gen initialization */
|
|
E_( imdct_init )(p_a52dec->p_imdct) ;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int decode_frame (a52dec_t * p_a52dec, s16 * buffer)
|
|
{
|
|
int i;
|
|
|
|
if (parse_bsi (p_a52dec))
|
|
{
|
|
msg_Warn( p_a52dec->p_fifo, "parse error" );
|
|
parse_auxdata (p_a52dec);
|
|
return 1;
|
|
}
|
|
|
|
/* compute downmix parameters
|
|
* downmix to tow channels for now */
|
|
p_a52dec->dm_par.clev = 0.0;
|
|
p_a52dec->dm_par.slev = 0.0;
|
|
p_a52dec->dm_par.unit = 1.0;
|
|
if (p_a52dec->bsi.acmod & 0x1) /* have center */
|
|
p_a52dec->dm_par.clev = cmixlev_lut[p_a52dec->bsi.cmixlev];
|
|
|
|
if (p_a52dec->bsi.acmod & 0x4) /* have surround channels */
|
|
p_a52dec->dm_par.slev = smixlev_lut[p_a52dec->bsi.surmixlev];
|
|
|
|
p_a52dec->dm_par.unit /= 1.0 + p_a52dec->dm_par.clev + p_a52dec->dm_par.slev;
|
|
p_a52dec->dm_par.clev *= p_a52dec->dm_par.unit;
|
|
p_a52dec->dm_par.slev *= p_a52dec->dm_par.unit;
|
|
|
|
for (i = 0; i < 6; i++) {
|
|
/* Initialize freq/time sample storage */
|
|
memset(p_a52dec->samples, 0, sizeof(float) * 256 *
|
|
(p_a52dec->bsi.nfchans + p_a52dec->bsi.lfeon));
|
|
|
|
|
|
if( p_a52dec->p_fifo->b_die || p_a52dec->p_fifo->b_error )
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
if( parse_audblk( p_a52dec, i ) )
|
|
{
|
|
msg_Warn( p_a52dec->p_fifo, "audioblock error" );
|
|
parse_auxdata( p_a52dec );
|
|
return 1;
|
|
}
|
|
|
|
if( p_a52dec->p_fifo->b_die || p_a52dec->p_fifo->b_error )
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
if( exponent_unpack( p_a52dec ) )
|
|
{
|
|
msg_Warn( p_a52dec->p_fifo, "unpack error" );
|
|
parse_auxdata( p_a52dec );
|
|
return 1;
|
|
}
|
|
|
|
bit_allocate (p_a52dec);
|
|
mantissa_unpack (p_a52dec);
|
|
|
|
if( p_a52dec->p_fifo->b_die || p_a52dec->p_fifo->b_error )
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
if (p_a52dec->bsi.acmod == 0x2)
|
|
{
|
|
rematrix (p_a52dec);
|
|
}
|
|
|
|
imdct (p_a52dec, buffer);
|
|
|
|
buffer += 2 * 256;
|
|
}
|
|
|
|
parse_auxdata (p_a52dec);
|
|
|
|
return 0;
|
|
}
|
|
|