ref: 471274ead7d0d41c9540b7f9e05ed015cd178b9b
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; }