ref: d39d1a5303541539f61488317b220c1eb724d7d3
dir: /sys/src/cmd/audio/mp3dec/synth.c/
/*
* libmad - MPEG audio decoder library
* Copyright (C) 2000-2004 Underbit Technologies, Inc.
*
* 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 02111-1307 USA
*
* $Id: synth.c,v 1.25 2004/01/23 09:41:33 rob Exp $
*/
# ifdef HAVE_CONFIG_H
# include "config.h"
# endif
# include "global.h"
# include "fixed.h"
# include "frame.h"
# include "synth.h"
/*
* NAME: synth->init()
* DESCRIPTION: initialize synth struct
*/
void mad_synth_init(struct mad_synth *synth)
{
mad_synth_mute(synth);
synth->phase = 0;
synth->pcm.samplerate = 0;
synth->pcm.channels = 0;
synth->pcm.length = 0;
}
/*
* NAME: synth->mute()
* DESCRIPTION: zero all polyphase filterbank values, resetting synthesis
*/
void mad_synth_mute(struct mad_synth *synth)
{
unsigned int ch, s, v;
for (ch = 0; ch < 2; ++ch) {
for (s = 0; s < 16; ++s) {
for (v = 0; v < 8; ++v) {
synth->filter[ch][0][0][s][v] = synth->filter[ch][0][1][s][v] =
synth->filter[ch][1][0][s][v] = synth->filter[ch][1][1][s][v] = 0;
}
}
}
}
/*
* An optional optimization called here the Subband Synthesis Optimization
* (SSO) improves the performance of subband synthesis at the expense of
* accuracy.
*
* The idea is to simplify 32x32->64-bit multiplication to 32x32->32 such
* that extra scaling and rounding are not necessary. This often allows the
* compiler to use faster 32-bit multiply-accumulate instructions instead of
* explicit 64-bit multiply, shift, and add instructions.
*
* SSO works like this: a full 32x32->64-bit multiply of two mad_fixed_t
* values requires the result to be right-shifted 28 bits to be properly
* scaled to the same fixed-point format. Right shifts can be applied at any
* time to either operand or to the result, so the optimization involves
* careful placement of these shifts to minimize the loss of accuracy.
*
* First, a 14-bit shift is applied with rounding at compile-time to the D[]
* table of coefficients for the subband synthesis window. This only loses 2
* bits of accuracy because the lower 12 bits are always zero. A second
* 12-bit shift occurs after the DCT calculation. This loses 12 bits of
* accuracy. Finally, a third 2-bit shift occurs just before the sample is
* saved in the PCM buffer. 14 + 12 + 2 == 28 bits.
*/
/* FPM_DEFAULT without OPT_SSO will actually lose accuracy and performance */
# if defined(FPM_DEFAULT) && !defined(OPT_SSO)
# define OPT_SSO
# endif
/* second SSO shift, with rounding */
# if defined(OPT_SSO)
# define SHIFT(x) (((x) + (1L << 11)) >> 12)
# else
# define SHIFT(x) (x)
# endif
/* possible DCT speed optimization */
# if defined(OPT_SPEED) && defined(MAD_F_MLX)
# define OPT_DCTO
# define MUL(x, y) \
({ mad_fixed64hi_t hi; \
mad_fixed64lo_t lo; \
MAD_F_MLX(hi, lo, (x), (y)); \
hi << (32 - MAD_F_SCALEBITS - 3); \
})
# else
# undef OPT_DCTO
# define MUL(x, y) mad_f_mul((x), (y))
# endif
/*
* NAME: dct32()
* DESCRIPTION: perform fast in[32]->out[32] DCT
*/
static
void dct32(mad_fixed_t const in[32], unsigned int slot,
mad_fixed_t lo[16][8], mad_fixed_t hi[16][8])
{
mad_fixed_t t0, t1, t2, t3, t4, t5, t6, t7;
mad_fixed_t t8, t9, t10, t11, t12, t13, t14, t15;
mad_fixed_t t16, t17, t18, t19, t20, t21, t22, t23;
mad_fixed_t t24, t25, t26, t27, t28, t29, t30, t31;
mad_fixed_t t32, t33, t34, t35, t36, t37, t38, t39;
mad_fixed_t t40, t41, t42, t43, t44, t45, t46, t47;
mad_fixed_t t48, t49, t50, t51, t52, t53, t54, t55;
mad_fixed_t t56, t57, t58, t59, t60, t61, t62, t63;
mad_fixed_t t64, t65, t66, t67, t68, t69, t70, t71;
mad_fixed_t t72, t73, t74, t75, t76, t77, t78, t79;
mad_fixed_t t80, t81, t82, t83, t84, t85, t86, t87;
mad_fixed_t t88, t89, t90, t91, t92, t93, t94, t95;
mad_fixed_t t96, t97, t98, t99, t100, t101, t102, t103;
mad_fixed_t t104, t105, t106, t107, t108, t109, t110, t111;
mad_fixed_t t112, t113, t114, t115, t116, t117, t118, t119;
mad_fixed_t t120, t121, t122, t123, t124, t125, t126, t127;
mad_fixed_t t128, t129, t130, t131, t132, t133, t134, t135;
mad_fixed_t t136, t137, t138, t139, t140, t141, t142, t143;
mad_fixed_t t144, t145, t146, t147, t148, t149, t150, t151;
mad_fixed_t t152, t153, t154, t155, t156, t157, t158, t159;
mad_fixed_t t160, t161, t162, t163, t164, t165, t166, t167;
mad_fixed_t t168, t169, t170, t171, t172, t173, t174, t175;
mad_fixed_t t176;
/* costab[i] = cos(PI / (2 * 32) * i) */
# if defined(OPT_DCTO)
# define costab1 MAD_F(0x7fd8878e)
# define costab2 MAD_F(0x7f62368f)
# define costab3 MAD_F(0x7e9d55fc)
# define costab4 MAD_F(0x7d8a5f40)
# define costab5 MAD_F(0x7c29fbee)
# define costab6 MAD_F(0x7a7d055b)
# define costab7 MAD_F(0x78848414)
# define costab8 MAD_F(0x7641af3d)
# define costab9 MAD_F(0x73b5ebd1)
# define costab10 MAD_F(0x70e2cbc6)
# define costab11 MAD_F(0x6dca0d14)
# define costab12 MAD_F(0x6a6d98a4)
# define costab13 MAD_F(0x66cf8120)
# define costab14 MAD_F(0x62f201ac)
# define costab15 MAD_F(0x5ed77c8a)
# define costab16 MAD_F(0x5a82799a)
# define costab17 MAD_F(0x55f5a4d2)
# define costab18 MAD_F(0x5133cc94)
# define costab19 MAD_F(0x4c3fdff4)
# define costab20 MAD_F(0x471cece7)
# define costab21 MAD_F(0x41ce1e65)
# define costab22 MAD_F(0x3c56ba70)
# define costab23 MAD_F(0x36ba2014)
# define costab24 MAD_F(0x30fbc54d)
# define costab25 MAD_F(0x2b1f34eb)
# define costab26 MAD_F(0x25280c5e)
# define costab27 MAD_F(0x1f19f97b)
# define costab28 MAD_F(0x18f8b83c)
# define costab29 MAD_F(0x12c8106f)
# define costab30 MAD_F(0x0c8bd35e)
# define costab31 MAD_F(0x0647d97c)
# else
# define costab1 MAD_F(0x0ffb10f2) /* 0.998795456 */
# define costab2 MAD_F(0x0fec46d2) /* 0.995184727 */
# define costab3 MAD_F(0x0fd3aac0) /* 0.989176510 */
# define costab4 MAD_F(0x0fb14be8) /* 0.980785280 */
# define costab5 MAD_F(0x0f853f7e) /* 0.970031253 */
# define costab6 MAD_F(0x0f4fa0ab) /* 0.956940336 */
# define costab7 MAD_F(0x0f109082) /* 0.941544065 */
# define costab8 MAD_F(0x0ec835e8) /* 0.923879533 */
# define costab9 MAD_F(0x0e76bd7a) /* 0.903989293 */
# define costab10 MAD_F(0x0e1c5979) /* 0.881921264 */
# define costab11 MAD_F(0x0db941a3) /* 0.857728610 */
# define costab12 MAD_F(0x0d4db315) /* 0.831469612 */
# define costab13 MAD_F(0x0cd9f024) /* 0.803207531 */
# define costab14 MAD_F(0x0c5e4036) /* 0.773010453 */
# define costab15 MAD_F(0x0bdaef91) /* 0.740951125 */
# define costab16 MAD_F(0x0b504f33) /* 0.707106781 */
# define costab17 MAD_F(0x0abeb49a) /* 0.671558955 */
# define costab18 MAD_F(0x0a267993) /* 0.634393284 */
# define costab19 MAD_F(0x0987fbfe) /* 0.595699304 */
# define costab20 MAD_F(0x08e39d9d) /* 0.555570233 */
# define costab21 MAD_F(0x0839c3cd) /* 0.514102744 */
# define costab22 MAD_F(0x078ad74e) /* 0.471396737 */
# define costab23 MAD_F(0x06d74402) /* 0.427555093 */
# define costab24 MAD_F(0x061f78aa) /* 0.382683432 */
# define costab25 MAD_F(0x0563e69d) /* 0.336889853 */
# define costab26 MAD_F(0x04a5018c) /* 0.290284677 */
# define costab27 MAD_F(0x03e33f2f) /* 0.242980180 */
# define costab28 MAD_F(0x031f1708) /* 0.195090322 */
# define costab29 MAD_F(0x0259020e) /* 0.146730474 */
# define costab30 MAD_F(0x01917a6c) /* 0.098017140 */
# define costab31 MAD_F(0x00c8fb30) /* 0.049067674 */
# endif
t0 = in[0] + in[31]; t16 = MUL(in[0] - in[31], costab1);
t1 = in[15] + in[16]; t17 = MUL(in[15] - in[16], costab31);
t41 = t16 + t17;
t59 = MUL(t16 - t17, costab2);
t33 = t0 + t1;
t50 = MUL(t0 - t1, costab2);
t2 = in[7] + in[24]; t18 = MUL(in[7] - in[24], costab15);
t3 = in[8] + in[23]; t19 = MUL(in[8] - in[23], costab17);
t42 = t18 + t19;
t60 = MUL(t18 - t19, costab30);
t34 = t2 + t3;
t51 = MUL(t2 - t3, costab30);
t4 = in[3] + in[28]; t20 = MUL(in[3] - in[28], costab7);
t5 = in[12] + in[19]; t21 = MUL(in[12] - in[19], costab25);
t43 = t20 + t21;
t61 = MUL(t20 - t21, costab14);
t35 = t4 + t5;
t52 = MUL(t4 - t5, costab14);
t6 = in[4] + in[27]; t22 = MUL(in[4] - in[27], costab9);
t7 = in[11] + in[20]; t23 = MUL(in[11] - in[20], costab23);
t44 = t22 + t23;
t62 = MUL(t22 - t23, costab18);
t36 = t6 + t7;
t53 = MUL(t6 - t7, costab18);
t8 = in[1] + in[30]; t24 = MUL(in[1] - in[30], costab3);
t9 = in[14] + in[17]; t25 = MUL(in[14] - in[17], costab29);
t45 = t24 + t25;
t63 = MUL(t24 - t25, costab6);
t37 = t8 + t9;
t54 = MUL(t8 - t9, costab6);
t10 = in[6] + in[25]; t26 = MUL(in[6] - in[25], costab13);
t11 = in[9] + in[22]; t27 = MUL(in[9] - in[22], costab19);
t46 = t26 + t27;
t64 = MUL(t26 - t27, costab26);
t38 = t10 + t11;
t55 = MUL(t10 - t11, costab26);
t12 = in[2] + in[29]; t28 = MUL(in[2] - in[29], costab5);
t13 = in[13] + in[18]; t29 = MUL(in[13] - in[18], costab27);
t47 = t28 + t29;
t65 = MUL(t28 - t29, costab10);
t39 = t12 + t13;
t56 = MUL(t12 - t13, costab10);
t14 = in[5] + in[26]; t30 = MUL(in[5] - in[26], costab11);
t15 = in[10] + in[21]; t31 = MUL(in[10] - in[21], costab21);
t48 = t30 + t31;
t66 = MUL(t30 - t31, costab22);
t40 = t14 + t15;
t57 = MUL(t14 - t15, costab22);
t69 = t33 + t34; t89 = MUL(t33 - t34, costab4);
t70 = t35 + t36; t90 = MUL(t35 - t36, costab28);
t71 = t37 + t38; t91 = MUL(t37 - t38, costab12);
t72 = t39 + t40; t92 = MUL(t39 - t40, costab20);
t73 = t41 + t42; t94 = MUL(t41 - t42, costab4);
t74 = t43 + t44; t95 = MUL(t43 - t44, costab28);
t75 = t45 + t46; t96 = MUL(t45 - t46, costab12);
t76 = t47 + t48; t97 = MUL(t47 - t48, costab20);
t78 = t50 + t51; t100 = MUL(t50 - t51, costab4);
t79 = t52 + t53; t101 = MUL(t52 - t53, costab28);
t80 = t54 + t55; t102 = MUL(t54 - t55, costab12);
t81 = t56 + t57; t103 = MUL(t56 - t57, costab20);
t83 = t59 + t60; t106 = MUL(t59 - t60, costab4);
t84 = t61 + t62; t107 = MUL(t61 - t62, costab28);
t85 = t63 + t64; t108 = MUL(t63 - t64, costab12);
t86 = t65 + t66; t109 = MUL(t65 - t66, costab20);
t113 = t69 + t70;
t114 = t71 + t72;
/* 0 */ hi[15][slot] = SHIFT(t113 + t114);
/* 16 */ lo[ 0][slot] = SHIFT(MUL(t113 - t114, costab16));
t115 = t73 + t74;
t116 = t75 + t76;
t32 = t115 + t116;
/* 1 */ hi[14][slot] = SHIFT(t32);
t118 = t78 + t79;
t119 = t80 + t81;
t58 = t118 + t119;
/* 2 */ hi[13][slot] = SHIFT(t58);
t121 = t83 + t84;
t122 = t85 + t86;
t67 = t121 + t122;
t49 = (t67 * 2) - t32;
/* 3 */ hi[12][slot] = SHIFT(t49);
t125 = t89 + t90;
t126 = t91 + t92;
t93 = t125 + t126;
/* 4 */ hi[11][slot] = SHIFT(t93);
t128 = t94 + t95;
t129 = t96 + t97;
t98 = t128 + t129;
t68 = (t98 * 2) - t49;
/* 5 */ hi[10][slot] = SHIFT(t68);
t132 = t100 + t101;
t133 = t102 + t103;
t104 = t132 + t133;
t82 = (t104 * 2) - t58;
/* 6 */ hi[ 9][slot] = SHIFT(t82);
t136 = t106 + t107;
t137 = t108 + t109;
t110 = t136 + t137;
t87 = (t110 * 2) - t67;
t77 = (t87 * 2) - t68;
/* 7 */ hi[ 8][slot] = SHIFT(t77);
t141 = MUL(t69 - t70, costab8);
t142 = MUL(t71 - t72, costab24);
t143 = t141 + t142;
/* 8 */ hi[ 7][slot] = SHIFT(t143);
/* 24 */ lo[ 8][slot] =
SHIFT((MUL(t141 - t142, costab16) * 2) - t143);
t144 = MUL(t73 - t74, costab8);
t145 = MUL(t75 - t76, costab24);
t146 = t144 + t145;
t88 = (t146 * 2) - t77;
/* 9 */ hi[ 6][slot] = SHIFT(t88);
t148 = MUL(t78 - t79, costab8);
t149 = MUL(t80 - t81, costab24);
t150 = t148 + t149;
t105 = (t150 * 2) - t82;
/* 10 */ hi[ 5][slot] = SHIFT(t105);
t152 = MUL(t83 - t84, costab8);
t153 = MUL(t85 - t86, costab24);
t154 = t152 + t153;
t111 = (t154 * 2) - t87;
t99 = (t111 * 2) - t88;
/* 11 */ hi[ 4][slot] = SHIFT(t99);
t157 = MUL(t89 - t90, costab8);
t158 = MUL(t91 - t92, costab24);
t159 = t157 + t158;
t127 = (t159 * 2) - t93;
/* 12 */ hi[ 3][slot] = SHIFT(t127);
t160 = (MUL(t125 - t126, costab16) * 2) - t127;
/* 20 */ lo[ 4][slot] = SHIFT(t160);
/* 28 */ lo[12][slot] =
SHIFT((((MUL(t157 - t158, costab16) * 2) - t159) * 2) - t160);
t161 = MUL(t94 - t95, costab8);
t162 = MUL(t96 - t97, costab24);
t163 = t161 + t162;
t130 = (t163 * 2) - t98;
t112 = (t130 * 2) - t99;
/* 13 */ hi[ 2][slot] = SHIFT(t112);
t164 = (MUL(t128 - t129, costab16) * 2) - t130;
t166 = MUL(t100 - t101, costab8);
t167 = MUL(t102 - t103, costab24);
t168 = t166 + t167;
t134 = (t168 * 2) - t104;
t120 = (t134 * 2) - t105;
/* 14 */ hi[ 1][slot] = SHIFT(t120);
t135 = (MUL(t118 - t119, costab16) * 2) - t120;
/* 18 */ lo[ 2][slot] = SHIFT(t135);
t169 = (MUL(t132 - t133, costab16) * 2) - t134;
t151 = (t169 * 2) - t135;
/* 22 */ lo[ 6][slot] = SHIFT(t151);
t170 = (((MUL(t148 - t149, costab16) * 2) - t150) * 2) - t151;
/* 26 */ lo[10][slot] = SHIFT(t170);
/* 30 */ lo[14][slot] =
SHIFT((((((MUL(t166 - t167, costab16) * 2) -
t168) * 2) - t169) * 2) - t170);
t171 = MUL(t106 - t107, costab8);
t172 = MUL(t108 - t109, costab24);
t173 = t171 + t172;
t138 = (t173 * 2) - t110;
t123 = (t138 * 2) - t111;
t139 = (MUL(t121 - t122, costab16) * 2) - t123;
t117 = (t123 * 2) - t112;
/* 15 */ hi[ 0][slot] = SHIFT(t117);
t124 = (MUL(t115 - t116, costab16) * 2) - t117;
/* 17 */ lo[ 1][slot] = SHIFT(t124);
t131 = (t139 * 2) - t124;
/* 19 */ lo[ 3][slot] = SHIFT(t131);
t140 = (t164 * 2) - t131;
/* 21 */ lo[ 5][slot] = SHIFT(t140);
t174 = (MUL(t136 - t137, costab16) * 2) - t138;
t155 = (t174 * 2) - t139;
t147 = (t155 * 2) - t140;
/* 23 */ lo[ 7][slot] = SHIFT(t147);
t156 = (((MUL(t144 - t145, costab16) * 2) - t146) * 2) - t147;
/* 25 */ lo[ 9][slot] = SHIFT(t156);
t175 = (((MUL(t152 - t153, costab16) * 2) - t154) * 2) - t155;
t165 = (t175 * 2) - t156;
/* 27 */ lo[11][slot] = SHIFT(t165);
t176 = (((((MUL(t161 - t162, costab16) * 2) -
t163) * 2) - t164) * 2) - t165;
/* 29 */ lo[13][slot] = SHIFT(t176);
/* 31 */ lo[15][slot] =
SHIFT((((((((MUL(t171 - t172, costab16) * 2) -
t173) * 2) - t174) * 2) - t175) * 2) - t176);
/*
* Totals:
* 80 multiplies
* 80 additions
* 119 subtractions
* 49 shifts (not counting SSO)
*/
}
# undef MUL
# undef SHIFT
/* third SSO shift and/or D[] optimization preshift */
# if defined(OPT_SSO)
# if MAD_F_FRACBITS != 28
# error "MAD_F_FRACBITS must be 28 to use OPT_SSO"
# endif
# define ML0(hi, lo, x, y) ((lo) = (x) * (y))
# define MLA(hi, lo, x, y) ((lo) += (x) * (y))
# define MLN(hi, lo) ((lo) = -(lo))
# define MLZ(hi, lo) ((void) (hi), (mad_fixed_t) (lo))
# define SHIFT(x) ((x) >> 2)
# define PRESHIFT(x) ((MAD_F(x) + (1L << 13)) >> 14)
# else
# define ML0(hi, lo, x, y) MAD_F_ML0((hi), (lo), (x), (y))
# define MLA(hi, lo, x, y) MAD_F_MLA((hi), (lo), (x), (y))
# define MLN(hi, lo) MAD_F_MLN((hi), (lo))
# define MLZ(hi, lo) MAD_F_MLZ((hi), (lo))
# define SHIFT(x) (x)
# if defined(MAD_F_SCALEBITS)
# undef MAD_F_SCALEBITS
# define MAD_F_SCALEBITS (MAD_F_FRACBITS - 12)
# define PRESHIFT(x) (MAD_F(x) >> 12)
# else
# define PRESHIFT(x) MAD_F(x)
# endif
# endif
static
mad_fixed_t const D[17][32] = {
# include "D.dat"
};
# if defined(ASO_SYNTH)
void synth_full(struct mad_synth *, struct mad_frame const *,
unsigned int, unsigned int);
# else
/*
* NAME: synth->full()
* DESCRIPTION: perform full frequency PCM synthesis
*/
static
void synth_full(struct mad_synth *synth, struct mad_frame const *frame,
unsigned int nch, unsigned int ns)
{
unsigned int phase, ch, s, sb, pe, po;
mad_fixed_t *pcm1, *pcm2, (*filter)[2][2][16][8];
mad_fixed_t const (*sbsample)[36][32];
register mad_fixed_t (*fe)[8], (*fx)[8], (*fo)[8];
register mad_fixed_t const (*Dptr)[32], *ptr;
register mad_fixed64hi_t hi;
register mad_fixed64lo_t lo;
for (ch = 0; ch < nch; ++ch) {
sbsample = &frame->sbsample[ch];
filter = &synth->filter[ch];
phase = synth->phase;
pcm1 = synth->pcm.samples[ch];
for (s = 0; s < ns; ++s) {
dct32((*sbsample)[s], phase >> 1,
(*filter)[0][phase & 1], (*filter)[1][phase & 1]);
pe = phase & ~1;
po = ((phase - 1) & 0xf) | 1;
/* calculate 32 samples */
fe = &(*filter)[0][ phase & 1][0];
fx = &(*filter)[0][~phase & 1][0];
fo = &(*filter)[1][~phase & 1][0];
Dptr = &D[0];
ptr = *Dptr + po;
ML0(hi, lo, (*fx)[0], ptr[ 0]);
MLA(hi, lo, (*fx)[1], ptr[14]);
MLA(hi, lo, (*fx)[2], ptr[12]);
MLA(hi, lo, (*fx)[3], ptr[10]);
MLA(hi, lo, (*fx)[4], ptr[ 8]);
MLA(hi, lo, (*fx)[5], ptr[ 6]);
MLA(hi, lo, (*fx)[6], ptr[ 4]);
MLA(hi, lo, (*fx)[7], ptr[ 2]);
MLN(hi, lo);
ptr = *Dptr + pe;
MLA(hi, lo, (*fe)[0], ptr[ 0]);
MLA(hi, lo, (*fe)[1], ptr[14]);
MLA(hi, lo, (*fe)[2], ptr[12]);
MLA(hi, lo, (*fe)[3], ptr[10]);
MLA(hi, lo, (*fe)[4], ptr[ 8]);
MLA(hi, lo, (*fe)[5], ptr[ 6]);
MLA(hi, lo, (*fe)[6], ptr[ 4]);
MLA(hi, lo, (*fe)[7], ptr[ 2]);
*pcm1++ = SHIFT(MLZ(hi, lo));
pcm2 = pcm1 + 30;
for (sb = 1; sb < 16; ++sb) {
++fe;
++Dptr;
/* D[32 - sb][i] == -D[sb][31 - i] */
ptr = *Dptr + po;
ML0(hi, lo, (*fo)[0], ptr[ 0]);
MLA(hi, lo, (*fo)[1], ptr[14]);
MLA(hi, lo, (*fo)[2], ptr[12]);
MLA(hi, lo, (*fo)[3], ptr[10]);
MLA(hi, lo, (*fo)[4], ptr[ 8]);
MLA(hi, lo, (*fo)[5], ptr[ 6]);
MLA(hi, lo, (*fo)[6], ptr[ 4]);
MLA(hi, lo, (*fo)[7], ptr[ 2]);
MLN(hi, lo);
ptr = *Dptr + pe;
MLA(hi, lo, (*fe)[7], ptr[ 2]);
MLA(hi, lo, (*fe)[6], ptr[ 4]);
MLA(hi, lo, (*fe)[5], ptr[ 6]);
MLA(hi, lo, (*fe)[4], ptr[ 8]);
MLA(hi, lo, (*fe)[3], ptr[10]);
MLA(hi, lo, (*fe)[2], ptr[12]);
MLA(hi, lo, (*fe)[1], ptr[14]);
MLA(hi, lo, (*fe)[0], ptr[ 0]);
*pcm1++ = SHIFT(MLZ(hi, lo));
ptr = *Dptr - pe;
ML0(hi, lo, (*fe)[0], ptr[31 - 16]);
MLA(hi, lo, (*fe)[1], ptr[31 - 14]);
MLA(hi, lo, (*fe)[2], ptr[31 - 12]);
MLA(hi, lo, (*fe)[3], ptr[31 - 10]);
MLA(hi, lo, (*fe)[4], ptr[31 - 8]);
MLA(hi, lo, (*fe)[5], ptr[31 - 6]);
MLA(hi, lo, (*fe)[6], ptr[31 - 4]);
MLA(hi, lo, (*fe)[7], ptr[31 - 2]);
ptr = *Dptr - po;
MLA(hi, lo, (*fo)[7], ptr[31 - 2]);
MLA(hi, lo, (*fo)[6], ptr[31 - 4]);
MLA(hi, lo, (*fo)[5], ptr[31 - 6]);
MLA(hi, lo, (*fo)[4], ptr[31 - 8]);
MLA(hi, lo, (*fo)[3], ptr[31 - 10]);
MLA(hi, lo, (*fo)[2], ptr[31 - 12]);
MLA(hi, lo, (*fo)[1], ptr[31 - 14]);
MLA(hi, lo, (*fo)[0], ptr[31 - 16]);
*pcm2-- = SHIFT(MLZ(hi, lo));
++fo;
}
++Dptr;
ptr = *Dptr + po;
ML0(hi, lo, (*fo)[0], ptr[ 0]);
MLA(hi, lo, (*fo)[1], ptr[14]);
MLA(hi, lo, (*fo)[2], ptr[12]);
MLA(hi, lo, (*fo)[3], ptr[10]);
MLA(hi, lo, (*fo)[4], ptr[ 8]);
MLA(hi, lo, (*fo)[5], ptr[ 6]);
MLA(hi, lo, (*fo)[6], ptr[ 4]);
MLA(hi, lo, (*fo)[7], ptr[ 2]);
*pcm1 = SHIFT(-MLZ(hi, lo));
pcm1 += 16;
phase = (phase + 1) % 16;
}
}
}
# endif
/*
* NAME: synth->half()
* DESCRIPTION: perform half frequency PCM synthesis
*/
static
void synth_half(struct mad_synth *synth, struct mad_frame const *frame,
unsigned int nch, unsigned int ns)
{
unsigned int phase, ch, s, sb, pe, po;
mad_fixed_t *pcm1, *pcm2, (*filter)[2][2][16][8];
mad_fixed_t const (*sbsample)[36][32];
register mad_fixed_t (*fe)[8], (*fx)[8], (*fo)[8];
register mad_fixed_t const (*Dptr)[32], *ptr;
register mad_fixed64hi_t hi;
register mad_fixed64lo_t lo;
for (ch = 0; ch < nch; ++ch) {
sbsample = &frame->sbsample[ch];
filter = &synth->filter[ch];
phase = synth->phase;
pcm1 = synth->pcm.samples[ch];
for (s = 0; s < ns; ++s) {
dct32((*sbsample)[s], phase >> 1,
(*filter)[0][phase & 1], (*filter)[1][phase & 1]);
pe = phase & ~1;
po = ((phase - 1) & 0xf) | 1;
/* calculate 16 samples */
fe = &(*filter)[0][ phase & 1][0];
fx = &(*filter)[0][~phase & 1][0];
fo = &(*filter)[1][~phase & 1][0];
Dptr = &D[0];
ptr = *Dptr + po;
ML0(hi, lo, (*fx)[0], ptr[ 0]);
MLA(hi, lo, (*fx)[1], ptr[14]);
MLA(hi, lo, (*fx)[2], ptr[12]);
MLA(hi, lo, (*fx)[3], ptr[10]);
MLA(hi, lo, (*fx)[4], ptr[ 8]);
MLA(hi, lo, (*fx)[5], ptr[ 6]);
MLA(hi, lo, (*fx)[6], ptr[ 4]);
MLA(hi, lo, (*fx)[7], ptr[ 2]);
MLN(hi, lo);
ptr = *Dptr + pe;
MLA(hi, lo, (*fe)[0], ptr[ 0]);
MLA(hi, lo, (*fe)[1], ptr[14]);
MLA(hi, lo, (*fe)[2], ptr[12]);
MLA(hi, lo, (*fe)[3], ptr[10]);
MLA(hi, lo, (*fe)[4], ptr[ 8]);
MLA(hi, lo, (*fe)[5], ptr[ 6]);
MLA(hi, lo, (*fe)[6], ptr[ 4]);
MLA(hi, lo, (*fe)[7], ptr[ 2]);
*pcm1++ = SHIFT(MLZ(hi, lo));
pcm2 = pcm1 + 14;
for (sb = 1; sb < 16; ++sb) {
++fe;
++Dptr;
/* D[32 - sb][i] == -D[sb][31 - i] */
if (!(sb & 1)) {
ptr = *Dptr + po;
ML0(hi, lo, (*fo)[0], ptr[ 0]);
MLA(hi, lo, (*fo)[1], ptr[14]);
MLA(hi, lo, (*fo)[2], ptr[12]);
MLA(hi, lo, (*fo)[3], ptr[10]);
MLA(hi, lo, (*fo)[4], ptr[ 8]);
MLA(hi, lo, (*fo)[5], ptr[ 6]);
MLA(hi, lo, (*fo)[6], ptr[ 4]);
MLA(hi, lo, (*fo)[7], ptr[ 2]);
MLN(hi, lo);
ptr = *Dptr + pe;
MLA(hi, lo, (*fe)[7], ptr[ 2]);
MLA(hi, lo, (*fe)[6], ptr[ 4]);
MLA(hi, lo, (*fe)[5], ptr[ 6]);
MLA(hi, lo, (*fe)[4], ptr[ 8]);
MLA(hi, lo, (*fe)[3], ptr[10]);
MLA(hi, lo, (*fe)[2], ptr[12]);
MLA(hi, lo, (*fe)[1], ptr[14]);
MLA(hi, lo, (*fe)[0], ptr[ 0]);
*pcm1++ = SHIFT(MLZ(hi, lo));
ptr = *Dptr - po;
ML0(hi, lo, (*fo)[7], ptr[31 - 2]);
MLA(hi, lo, (*fo)[6], ptr[31 - 4]);
MLA(hi, lo, (*fo)[5], ptr[31 - 6]);
MLA(hi, lo, (*fo)[4], ptr[31 - 8]);
MLA(hi, lo, (*fo)[3], ptr[31 - 10]);
MLA(hi, lo, (*fo)[2], ptr[31 - 12]);
MLA(hi, lo, (*fo)[1], ptr[31 - 14]);
MLA(hi, lo, (*fo)[0], ptr[31 - 16]);
ptr = *Dptr - pe;
MLA(hi, lo, (*fe)[0], ptr[31 - 16]);
MLA(hi, lo, (*fe)[1], ptr[31 - 14]);
MLA(hi, lo, (*fe)[2], ptr[31 - 12]);
MLA(hi, lo, (*fe)[3], ptr[31 - 10]);
MLA(hi, lo, (*fe)[4], ptr[31 - 8]);
MLA(hi, lo, (*fe)[5], ptr[31 - 6]);
MLA(hi, lo, (*fe)[6], ptr[31 - 4]);
MLA(hi, lo, (*fe)[7], ptr[31 - 2]);
*pcm2-- = SHIFT(MLZ(hi, lo));
}
++fo;
}
++Dptr;
ptr = *Dptr + po;
ML0(hi, lo, (*fo)[0], ptr[ 0]);
MLA(hi, lo, (*fo)[1], ptr[14]);
MLA(hi, lo, (*fo)[2], ptr[12]);
MLA(hi, lo, (*fo)[3], ptr[10]);
MLA(hi, lo, (*fo)[4], ptr[ 8]);
MLA(hi, lo, (*fo)[5], ptr[ 6]);
MLA(hi, lo, (*fo)[6], ptr[ 4]);
MLA(hi, lo, (*fo)[7], ptr[ 2]);
*pcm1 = SHIFT(-MLZ(hi, lo));
pcm1 += 8;
phase = (phase + 1) % 16;
}
}
}
/*
* NAME: synth->frame()
* DESCRIPTION: perform PCM synthesis of frame subband samples
*/
void mad_synth_frame(struct mad_synth *synth, struct mad_frame const *frame)
{
unsigned int nch, ns;
void (*synth_frame)(struct mad_synth *, struct mad_frame const *,
unsigned int, unsigned int);
nch = MAD_NCHANNELS(&frame->header);
ns = MAD_NSBSAMPLES(&frame->header);
synth->pcm.samplerate = frame->header.samplerate;
synth->pcm.channels = nch;
synth->pcm.length = 32 * ns;
synth_frame = synth_full;
if (frame->options & MAD_OPTION_HALFSAMPLERATE) {
synth->pcm.samplerate /= 2;
synth->pcm.length /= 2;
synth_frame = synth_half;
}
synth_frame(synth, frame, nch, ns);
synth->phase = (synth->phase + ns) % 16;
}