jedi-outcast/CODE-mp/mp3code/cupini.c
2013-04-22 15:25:59 +10:00

401 lines
13 KiB
C

#pragma warning(disable:4206) // nonstandard extension used : translation unit is empty
#ifdef COMPILE_ME
/*____________________________________________________________________________
FreeAmp - The Free MP3 Player
MP3 Decoder originally Copyright (C) 1995-1997 Xing Technology
Corp. http://www.xingtech.com
Portions Copyright (C) 1998-1999 EMusic.com
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., 675 Mass Ave, Cambridge, MA 02139, USA.
$Id: cupini.c,v 1.3 1999/10/19 07:13:08 elrod Exp $
____________________________________________________________________________*/
/*=========================================================
initialization for cup.c - include to cup.c
mpeg audio decoder portable "c"
mod 8/6/96 add 8 bit output
mod 5/10/95 add quick (low precision) window
mod 5/16/95 sb limit for reduced samprate output
changed from 94% to 100% of Nyquist sb
mod 11/15/95 for Layer I
=========================================================*/
/*-- compiler bug, floating constant overflow w/ansi --*/
#ifdef _MSC_VER
#pragma warning(disable:4056)
#endif
static const long steps[18] =
{
0, 3, 5, 7, 9, 15, 31, 63, 127,
255, 511, 1023, 2047, 4095, 8191, 16383, 32767, 65535};
/* ABCD_INDEX = lookqt[mode][sr_index][br_index] */
/* -1 = invalid */
static const signed char lookqt[4][3][16] =
{
{{1, -1, -1, -1, 2, -1, 2, 0, 0, 0, 1, 1, 1, 1, 1, -1}, /* 44ks stereo */
{0, -1, -1, -1, 2, -1, 2, 0, 0, 0, 0, 0, 0, 0, 0, -1}, /* 48ks */
{1, -1, -1, -1, 3, -1, 3, 0, 0, 0, 1, 1, 1, 1, 1, -1}}, /* 32ks */
{{1, -1, -1, -1, 2, -1, 2, 0, 0, 0, 1, 1, 1, 1, 1, -1}, /* 44ks joint stereo */
{0, -1, -1, -1, 2, -1, 2, 0, 0, 0, 0, 0, 0, 0, 0, -1}, /* 48ks */
{1, -1, -1, -1, 3, -1, 3, 0, 0, 0, 1, 1, 1, 1, 1, -1}}, /* 32ks */
{{1, -1, -1, -1, 2, -1, 2, 0, 0, 0, 1, 1, 1, 1, 1, -1}, /* 44ks dual chan */
{0, -1, -1, -1, 2, -1, 2, 0, 0, 0, 0, 0, 0, 0, 0, -1}, /* 48ks */
{1, -1, -1, -1, 3, -1, 3, 0, 0, 0, 1, 1, 1, 1, 1, -1}}, /* 32ks */
// mono extended beyond legal br index
// 1,2,2,0,0,0,1,1,1,1,1,1,1,1,1,-1, /* 44ks single chan */
// 0,2,2,0,0,0,0,0,0,0,0,0,0,0,0,-1, /* 48ks */
// 1,3,3,0,0,0,1,1,1,1,1,1,1,1,1,-1, /* 32ks */
// legal mono
{{1, 2, 2, 0, 0, 0, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1}, /* 44ks single chan */
{0, 2, 2, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -1, -1, -1}, /* 48ks */
{1, 3, 3, 0, 0, 0, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1}}, /* 32ks */
};
static const long sr_table[8] =
{22050L, 24000L, 16000L, 1L,
44100L, 48000L, 32000L, 1L};
/* bit allocation table look up */
/* table per mpeg spec tables 3b2a/b/c/d /e is mpeg2 */
/* look_bat[abcd_index][4][16] */
static const unsigned char look_bat[5][4][16] =
{
/* LOOK_BATA */
{{0, 1, 3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17},
{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17},
{0, 1, 2, 3, 4, 5, 6, 17, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 1, 2, 17, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
/* LOOK_BATB */
{{0, 1, 3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17},
{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17},
{0, 1, 2, 3, 4, 5, 6, 17, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 1, 2, 17, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
/* LOOK_BATC */
{{0, 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 1, 2, 4, 5, 6, 7, 8, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
/* LOOK_BATD */
{{0, 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 1, 2, 4, 5, 6, 7, 8, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
/* LOOK_BATE */
{{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 1, 2, 4, 5, 6, 7, 8, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 1, 2, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
};
/* look_nbat[abcd_index]][4] */
static const unsigned char look_nbat[5][4] =
{
{3, 8, 12, 4},
{3, 8, 12, 7},
{2, 0, 6, 0},
{2, 0, 10, 0},
{4, 0, 7, 19},
};
void sbt_mono(float *sample, short *pcm, int n);
void sbt_dual(float *sample, short *pcm, int n);
void sbt_dual_mono(float *sample, short *pcm, int n);
void sbt_dual_left(float *sample, short *pcm, int n);
void sbt_dual_right(float *sample, short *pcm, int n);
void sbt16_mono(float *sample, short *pcm, int n);
void sbt16_dual(float *sample, short *pcm, int n);
void sbt16_dual_mono(float *sample, short *pcm, int n);
void sbt16_dual_left(float *sample, short *pcm, int n);
void sbt16_dual_right(float *sample, short *pcm, int n);
void sbt8_mono(float *sample, short *pcm, int n);
void sbt8_dual(float *sample, short *pcm, int n);
void sbt8_dual_mono(float *sample, short *pcm, int n);
void sbt8_dual_left(float *sample, short *pcm, int n);
void sbt8_dual_right(float *sample, short *pcm, int n);
/*--- 8 bit output ---*/
void sbtB_mono(float *sample, unsigned char *pcm, int n);
void sbtB_dual(float *sample, unsigned char *pcm, int n);
void sbtB_dual_mono(float *sample, unsigned char *pcm, int n);
void sbtB_dual_left(float *sample, unsigned char *pcm, int n);
void sbtB_dual_right(float *sample, unsigned char *pcm, int n);
void sbtB16_mono(float *sample, unsigned char *pcm, int n);
void sbtB16_dual(float *sample, unsigned char *pcm, int n);
void sbtB16_dual_mono(float *sample, unsigned char *pcm, int n);
void sbtB16_dual_left(float *sample, unsigned char *pcm, int n);
void sbtB16_dual_right(float *sample, unsigned char *pcm, int n);
void sbtB8_mono(float *sample, unsigned char *pcm, int n);
void sbtB8_dual(float *sample, unsigned char *pcm, int n);
void sbtB8_dual_mono(float *sample, unsigned char *pcm, int n);
void sbtB8_dual_left(float *sample, unsigned char *pcm, int n);
void sbtB8_dual_right(float *sample, unsigned char *pcm, int n);
static const SBT_FUNCTION sbt_table[2][3][5] =
{
{{sbt_mono, sbt_dual, sbt_dual_mono, sbt_dual_left, sbt_dual_right},
{sbt16_mono, sbt16_dual, sbt16_dual_mono, sbt16_dual_left, sbt16_dual_right},
{sbt8_mono, sbt8_dual, sbt8_dual_mono, sbt8_dual_left, sbt8_dual_right}},
{{(SBT_FUNCTION) sbtB_mono,
(SBT_FUNCTION) sbtB_dual,
(SBT_FUNCTION) sbtB_dual_mono,
(SBT_FUNCTION) sbtB_dual_left,
(SBT_FUNCTION) sbtB_dual_right},
{(SBT_FUNCTION) sbtB16_mono,
(SBT_FUNCTION) sbtB16_dual,
(SBT_FUNCTION) sbtB16_dual_mono,
(SBT_FUNCTION) sbtB16_dual_left,
(SBT_FUNCTION) sbtB16_dual_right},
{(SBT_FUNCTION) sbtB8_mono,
(SBT_FUNCTION) sbtB8_dual,
(SBT_FUNCTION) sbtB8_dual_mono,
(SBT_FUNCTION) sbtB8_dual_left,
(SBT_FUNCTION) sbtB8_dual_right}},
};
static const int out_chans[5] =
{1, 2, 1, 1, 1};
int audio_decode_initL1(MPEG_HEAD * h, int framebytes_arg,
int reduction_code, int transform_code, int convert_code,
int freq_limit);
void sbt_init();
IN_OUT L1audio_decode(unsigned char *bs, signed short *pcm);
IN_OUT L2audio_decode(unsigned char *bs, signed short *pcm);
IN_OUT L3audio_decode(unsigned char *bs, unsigned char *pcm);
static const AUDIO_DECODE_ROUTINE decode_routine_table[4] =
{
L2audio_decode,
(AUDIO_DECODE_ROUTINE)L3audio_decode,
L2audio_decode,
L1audio_decode,};
/*---------------------------------------------------------*/
static void table_init()
{
int i, j;
int code;
static int iOnceOnly=0;
if (!iOnceOnly++)
{
/*-- c_values (dequant) --*/
for (i = 1; i < 18; i++)
look_c_value[i] = 2.0F / steps[i];
/*-- scale factor table, scale by 32768 for 16 pcm output --*/
for (i = 0; i < 64; i++)
sf_table[i] = (float) (32768.0 * 2.0 * pow(2.0, -i / 3.0));
/*-- grouped 3 level lookup table 5 bit token --*/
for (i = 0; i < 32; i++)
{
code = i;
for (j = 0; j < 3; j++)
{
group3_table[i][j] = (char) ((code % 3) - 1);
code /= 3;
}
}
/*-- grouped 5 level lookup table 7 bit token --*/
for (i = 0; i < 128; i++)
{
code = i;
for (j = 0; j < 3; j++)
{
group5_table[i][j] = (char) ((code % 5) - 2);
code /= 5;
}
}
/*-- grouped 9 level lookup table 10 bit token --*/
for (i = 0; i < 1024; i++)
{
code = i;
for (j = 0; j < 3; j++)
{
group9_table[i][j] = (short) ((code % 9) - 4);
code /= 9;
}
}
}
}
/*---------------------------------------------------------*/
int L1audio_decode_init(MPEG_HEAD * h, int framebytes_arg,
int reduction_code, int transform_code, int convert_code,
int freq_limit);
int L3audio_decode_init(MPEG_HEAD * h, int framebytes_arg,
int reduction_code, int transform_code, int convert_code,
int freq_limit);
/*---------------------------------------------------------*/
/* mpeg_head defined in mhead.h frame bytes is without pad */
int audio_decode_init(MPEG_HEAD * h, int framebytes_arg,
int reduction_code, int transform_code, int convert_code,
int freq_limit)
{
int i, j, k;
static int first_pass = 1;
int abcd_index;
long samprate;
int limit;
int bit_code;
if (first_pass)
{
table_init();
first_pass = 0;
}
/* select decoder routine Layer I,II,III */
audio_decode_routine = decode_routine_table[h->option & 3];
if (h->option == 3) /* layer I */
return L1audio_decode_init(h, framebytes_arg,
reduction_code, transform_code, convert_code, freq_limit);
if (h->option == 1) /* layer III */
return L3audio_decode_init(h, framebytes_arg,
reduction_code, transform_code, convert_code, freq_limit);
transform_code = transform_code; /* not used, asm compatability */
bit_code = 0;
if (convert_code & 8)
bit_code = 1;
convert_code = convert_code & 3; /* higher bits used by dec8 freq cvt */
if (reduction_code < 0)
reduction_code = 0;
if (reduction_code > 2)
reduction_code = 2;
if (freq_limit < 1000)
freq_limit = 1000;
pMP3Stream->framebytes = framebytes_arg;
/* check if code handles */
if (h->option != 2)
return 0; /* layer II only */
if (h->sr_index == 3)
return 0; /* reserved */
/* compute abcd index for bit allo table selection */
if (h->id) /* mpeg 1 */
abcd_index = lookqt[h->mode][h->sr_index][h->br_index];
else
abcd_index = 4; /* mpeg 2 */
if (abcd_index < 0)
return 0; // fail invalid Layer II bit rate index
for (i = 0; i < 4; i++)
for (j = 0; j < 16; j++)
pMP3Stream->bat[i][j] = look_bat[abcd_index][i][j];
for (i = 0; i < 4; i++)
pMP3Stream->nbat[i] = look_nbat[abcd_index][i];
pMP3Stream->max_sb = pMP3Stream->nbat[0] + pMP3Stream->nbat[1] + pMP3Stream->nbat[2] + pMP3Stream->nbat[3];
/*----- compute pMP3Stream->nsb_limit --------*/
samprate = sr_table[4 * h->id + h->sr_index];
pMP3Stream->nsb_limit = (freq_limit * 64L + samprate / 2) / samprate;
/*- caller limit -*/
/*---- limit = 0.94*(32>>reduction_code); ----*/
limit = (32 >> reduction_code);
if (limit > 8)
limit--;
if (pMP3Stream->nsb_limit > limit)
pMP3Stream->nsb_limit = limit;
if (pMP3Stream->nsb_limit > pMP3Stream->max_sb)
pMP3Stream->nsb_limit = pMP3Stream->max_sb;
pMP3Stream->outvalues = 1152 >> reduction_code;
if (h->mode != 3)
{ /* adjust for 2 channel modes */
for (i = 0; i < 4; i++)
pMP3Stream->nbat[i] *= 2;
pMP3Stream->max_sb *= 2;
pMP3Stream->nsb_limit *= 2;
}
/* set sbt function */
k = 1 + convert_code;
if (h->mode == 3)
{
k = 0;
}
pMP3Stream->sbt = sbt_table[bit_code][reduction_code][k];
pMP3Stream->outvalues *= out_chans[k];
if (bit_code)
pMP3Stream->outbytes = pMP3Stream->outvalues;
else
pMP3Stream->outbytes = sizeof(short) * pMP3Stream->outvalues;
decinfo.channels = out_chans[k];
decinfo.outvalues = pMP3Stream->outvalues;
decinfo.samprate = samprate >> reduction_code;
if (bit_code)
decinfo.bits = 8;
else
decinfo.bits = sizeof(short) * 8;
decinfo.framebytes = pMP3Stream->framebytes;
decinfo.type = 0;
/* clear sample buffer, unused sub bands must be 0 */
for (i = 0; i < 2304*2; i++) // the *2 here was inserted by me just in case, since the array is now *2, because of stereo files unpacking at 4608 bytes per frame (which may or may not be relevant, but in any case I don't think we use the L1 versions of MP3 now anyway
sample[i] = 0.0F;
/* init sub-band transform */
sbt_init();
return 1;
}
/*---------------------------------------------------------*/
void audio_decode_info(DEC_INFO * info)
{
*info = decinfo; /* info return, call after init */
}
/*---------------------------------------------------------*/
void decode_table_init()
{
/* dummy for asm version compatability */
}
/*---------------------------------------------------------*/
#endif // #ifdef COMPILE_ME