/* * MP3 window subband -> subband filtering -> mdct routine * * Copyright (c) 1999 Takehiro TOMINAGA * * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library 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 * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ /* * Special Thanks to Patrick De Smet for your advices. */ #include "util.h" #include "l3side.h" #include "newmdct.h" #define SCALE 32768 #ifndef USE_GOGO_SUBBAND static const FLOAT8 enwindow[] = { 3.5758972e-02, 3.401756e-03, 9.83715e-04, 9.9182e-05, /* 15*/ -4.77e-07, 1.03951e-04, 9.53674e-04, 2.841473e-03, 1.2398e-05, 1.91212e-04, 2.283096e-03,1.6994476e-02, 1.8756866e-02, 2.630711e-03, 2.47478e-04, 1.4782e-05, 3.5694122e-02, 3.643036e-03, 9.91821e-04, 9.6321e-05, /* 14*/ -4.77e-07, 1.05858e-04, 9.30786e-04, 2.521515e-03, 1.1444e-05, 1.65462e-04, 2.110004e-03,1.6112804e-02, 1.9634247e-02, 2.803326e-03, 2.77042e-04, 1.6689e-05, -3.5586357e-02, -3.858566e-03, -9.95159e-04, -9.3460e-05, /* 13*/ 4.77e-07, -1.07288e-04, -9.02653e-04, -2.174854e-03, -1.0014e-05, -1.40190e-04, -1.937389e-03,-1.5233517e-02, -2.0506859e-02, -2.974033e-03, -3.07560e-04, -1.8120e-05, 3.5435200e-02, 4.049301e-03, 9.94205e-04, 9.0599e-05, /* 12*/ -4.77e-07, 1.08242e-04, 8.68797e-04, 1.800537e-03, 9.060e-06, 1.16348e-04, 1.766682e-03,1.4358521e-02, 2.1372318e-02, 3.14188e-03, 3.39031e-04, 1.9550e-05, -3.5242081e-02, -4.215240e-03, - 9.89437e-04,- 8.7261e-05, /* 11*/ 4.77e-07, - 1.08719e-04, - 8.29220e-04,- 1.399517e-03, - 8.106e-06, - 9.3937e-05, -1.597881e-03,-1.3489246e-02, -2.2228718e-02, -3.306866e-03, - 3.71456e-04,- 2.1458e-05, 3.5007000e-02, 4.357815e-03, 9.80854e-04, 8.3923e-05, /* 10*/ -4.77e-07, 1.08719e-04, 7.8392e-04, 9.71317e-04, 7.629e-06, 7.2956e-05, 1.432419e-03,1.2627602e-02, 2.3074150e-02, 3.467083e-03, 4.04358e-04, 2.3365e-05, 3.4730434e-02, 4.477024e-03, 9.68933e-04, 8.0585e-05, /* 9*/ -9.54e-07, 1.08242e-04, 7.31945e-04, 5.15938e-04, 6.676e-06, 5.2929e-05, 1.269817e-03,1.1775017e-02, 2.3907185e-02, 3.622532e-03, 4.38213e-04, 2.5272e-05, 3.4412861e-02, 4.573822e-03, 9.54151e-04, 7.6771e-05, /* 8*/ -9.54e-07, 1.06812e-04, 6.74248e-04, 3.3379e-05, 6.199e-06, 3.4332e-05, 1.111031e-03,1.0933399e-02, 2.4725437e-02, 3.771782e-03, 4.72546e-04, 2.7657e-05, 3.4055710e-02, 4.649162e-03, 9.35555e-04, 7.3433e-05, /* 7*/ -9.54e-07, 1.05381e-04, 6.10352e-04, -4.75883e-04, 5.245e-06, 1.7166e-05, 9.56535e-04,1.0103703e-02, 2.5527000e-02, 3.914356e-03, 5.07355e-04, 3.0041e-05, -3.3659935e-02, -4.703045e-03, -9.15051e-04,- 7.0095e-05, /* 6*/ 9.54e-07, - 1.02520e-04, -5.39303e-04, 1.011848e-03, - 4.768e-06, - 9.54e-07, -8.06808e-04,- 9.287834e-03, -2.6310921e-02, -4.048824e-03, -5.42164e-04,- 3.2425e-05, 3.3225536e-02, 4.737377e-03, 8.91685e-04, 6.6280e-05, /* 5*/ -1.431e-06, 9.9182e-05, 4.62532e-04,-1.573563e-03, 4.292e-06, -1.3828e-05, 6.61850e-04, 8.487225e-03, 2.7073860e-02, 4.174709e-03, 5.76973e-04, 3.4809e-05, 3.2754898e-02, 4.752159e-03, 8.66413e-04, 6.2943e-05, /* 4*/ -1.431e-06, 9.5367e-05, 3.78609e-04,-2.161503e-03, 3.815e-06, -2.718e-05, 5.22137e-04, 7.703304e-03, 2.7815342e-02, 4.290581e-03, 6.11782e-04, 3.7670e-05, -3.2248020e-02, -4.748821e-03, -8.38757e-04,- 5.9605e-05, /* 3*/ 1.907e-06, - 9.0122e-05, -2.88486e-04, 2.774239e-03, - 3.338e-06, 3.9577e-05, -3.88145e-04,- 6.937027e-03, -2.8532982e-02, -4.395962e-03, -6.46591e-04,- 4.0531e-05, 3.1706810e-02, 4.728317e-03, 8.09669e-04, 5.579e-05, -1.907e-06, 8.4400e-05, 1.91689e-04,-3.411293e-03, 3.338e-06, -5.0545e-05, 2.59876e-04, 6.189346e-03, 2.9224873e-02, 4.489899e-03, 6.80923e-04, 4.3392e-05, 3.1132698e-02, 4.691124e-03, 7.79152e-04, 5.2929e-05, -2.384e-06, 7.7724e-05, 8.8215e-05,-4.072189e-03, 2.861e-06, -6.0558e-05, 1.37329e-04, 5.462170e-03, 2.9890060e-02, 4.570484e-03, 7.14302e-04, 4.6253e-05, 3.5780907e-02,1.7876148e-02, 3.134727e-03, 2.457142e-03, 9.71317e-04, 2.18868e-04, 1.01566e-04, 1.3828e-05, 3.0526638e-02, 4.638195e-03, 7.47204e-04, 4.9591e-05, 4.756451e-03, 2.1458e-05, -6.9618e-05, 2.384e-06, }; #endif #define NS 12 #define NL 36 static FLOAT8 ca[8], cs[8]; static FLOAT8 win[4][36]; static FLOAT8 tantab_l[NL/4]; static FLOAT8 tritab_s[NS/4*2]; /************************************************************************ * * window_subband() * * PURPOSE: Overlapping window on PCM samples * * SEMANTICS: * 32 16-bit pcm samples are scaled to fractional 2's complement and * concatenated to the end of the window buffer #x#. The updated window * buffer #x# is then windowed by the analysis window #c# to produce the * windowed sample #z# * ************************************************************************/ /* * new IDCT routine written by Naoki Shibata */ INLINE static void idct32(FLOAT8 a[]) { /* returns sum_j=0^31 a[j]*cos(PI*j*(k+1/2)/32), 0<=k<32 */ static const FLOAT8 costab[] = { 0.54119610014619701222, 1.3065629648763763537, 0.50979557910415917998, 2.5629154477415054814, 0.89997622313641556513, 0.60134488693504528634, 0.5024192861881556782, 5.1011486186891552563, 0.78815462345125020249, 0.64682178335999007679, 0.56694403481635768927, 1.0606776859903470633, 1.7224470982383341955, 0.52249861493968885462, 10.19000812354803287, 0.674808341455005678, 1.1694399334328846596, 0.53104259108978413284, 2.0577810099534108446, 0.58293496820613388554, 0.83934964541552681272, 0.50547095989754364798, 3.4076084184687189804, 0.62250412303566482475, 0.97256823786196078263, 0.51544730992262455249, 1.4841646163141661852, 0.5531038960344445421, 0.74453627100229857749, 0.5006029982351962726, }; int i; #ifdef USE_GOGO_SUBBAND a[31] += a[29]; a[29] += a[27]; a[27] += a[25]; a[25] += a[23]; a[23] += a[21]; a[21] += a[19]; a[19] += a[17]; a[17] += a[15]; a[15] += a[13]; a[13] += a[11]; a[11] += a[ 9]; a[ 9] += a[ 7]; a[ 7] += a[ 5]; a[ 5] += a[ 3]; a[ 3] += a[ 1]; a[31] += a[27]; a[27] += a[23]; a[30] += a[26]; a[26] += a[22]; a[23] += a[19]; a[19] += a[15]; a[22] += a[18]; a[18] += a[14]; a[15] += a[11]; a[11] += a[ 7]; a[14] += a[10]; a[10] += a[ 6]; a[ 7] += a[ 3]; a[ 6] += a[ 2]; a[31] += a[23]; a[23] += a[15]; a[15] += a[ 7]; a[30] += a[22]; a[22] += a[14]; a[14] += a[ 6]; a[29] += a[21]; a[21] += a[13]; a[13] += a[ 5]; a[28] += a[20]; a[20] += a[12]; a[12] += a[ 4]; a[ 6] = -a[ 6]; a[22] = -a[22]; a[12] = -a[12]; a[28] = -a[28]; a[13] = -a[13]; a[29] = -a[29]; a[15] = -a[15]; a[31] = -a[31]; a[ 3] = -a[ 3]; a[19] = -a[19]; a[11] = -a[11]; a[27] = -a[27]; #else a[31] -= a[29]; a[29] -= a[27]; a[27] += a[25]; a[25] += a[23]; a[23] -= a[21]; a[21] += a[19]; a[19] -= a[17]; a[17] += a[15]; a[15] -= a[13]; a[13] += a[11]; a[11] -= a[ 9]; a[ 9] += a[ 7]; a[ 7] += a[ 5]; a[ 5] -= a[ 3]; a[ 3] -= a[ 1]; a[31] += a[27]; a[27] = -(a[27]+a[23]); a[30] -= a[26]; a[26] = a[22] - a[26]; a[23] -= a[19]; a[19] -= a[15]; a[22] += a[18]; a[18] += a[14]; a[15] -= a[11]; a[11] -= a[ 7]; a[14] += a[10]; a[10] -= a[ 6]; a[ 7] -= a[ 3]; a[ 6] -= a[ 2]; a[31] = -(a[23]+a[31]); a[23] += a[15]; a[15] = -(a[15]+a[ 7]); a[30] += a[22]; a[22] = -(a[14]+a[22]); a[14] -= a[ 6]; a[29] += a[21]; a[21] = -(a[21]+a[13]); a[13] -= a[ 5]; a[28] = -(a[28]+a[20]); a[20] += a[12]; a[12] = -(a[ 4]+a[12]); #endif { FLOAT8 const *xp = costab; int p0,p1; for (i = 0; i < 8; i++) { FLOAT8 x1, x2, x3, x4; x3 = a[i+16] * (SQRT2*0.5); x4 = a[i] - x3; x3 = a[i] + x3; x2 = -(a[24+i] + a[i+8]) * (SQRT2*0.5); x1 = (a[i+8] - x2) * xp[0]; x2 = (a[i+8] + x2) * xp[1]; a[i ] = x3 + x1; a[i+ 8] = x4 - x2; a[i+16] = x4 + x2; a[i+24] = x3 - x1; } xp += 2; for (i = 0; i < 4; i++) { FLOAT8 xr; xr = a[i+28] * xp[0]; a[i+28] = (a[i] - xr); a[i ] = (a[i] + xr); xr = a[i+4] * xp[1]; a[i+ 4] = (a[i+24] - xr); a[i+24] = (a[i+24] + xr); xr = a[i+20] * xp[2]; a[i+20] = (a[i+8] - xr); a[i+ 8] = (a[i+8] + xr); xr = a[i+12] * xp[3]; a[i+12] = (a[i+16] - xr); a[i+16] = (a[i+16] + xr); } xp += 4; for (i = 0; i < 4; i++) { FLOAT8 xr; xr = a[30-i*4] * xp[0]; a[30-i*4] = (a[i*4] - xr); a[ i*4] = (a[i*4] + xr); xr = a[ 2+i*4] * xp[1]; a[ 2+i*4] = (a[28-i*4] - xr); a[28-i*4] = (a[28-i*4] + xr); xr = a[31-i*4] * xp[0]; a[31-i*4] = (a[1+i*4] - xr); a[ 1+i*4] = (a[1+i*4] + xr); xr = a[ 3+i*4] * xp[1]; a[ 3+i*4] = (a[29-i*4] - xr); a[29-i*4] = (a[29-i*4] + xr); xp += 2; } p0 = 30; p1 = 1; do { FLOAT8 xr = a[p1] * *xp++; a[p1] = (a[p0] - xr); a[p0] = (a[p0] + xr); p0 -= 2; p1 += 2; } while (p0 >= 0); } } INLINE static void window_subband(sample_t *x1, FLOAT8 a[SBLIMIT]) { int i; FLOAT8 const *wp = enwindow; sample_t *x2 = &x1[238-14-286]; for (i = -15; i < 0; i++) { FLOAT8 w, s, t; w = wp[ 0]; s = x2[ 32] * w; t = x1[- 32] * w; w = wp[ 1]; s += x2[ 96] * w; t += x1[- 96] * w; w = wp[ 2]; s += x2[ 160] * w; t += x1[-160] * w; w = wp[ 3]; s += x2[ 224] * w; t += x1[-224] * w; w = wp[ 4]; s += x2[-224] * w; t += x1[ 224] * w; w = wp[ 5]; s += x2[-160] * w; t += x1[ 160] * w; w = wp[ 6]; s += x2[- 96] * w; t += x1[ 96] * w; w = wp[ 7]; s += x2[- 32] * w; t += x1[ 32] * w; w = wp[ 8]; s += x1[-256] * w; t -= x2[ 256] * w; w = wp[ 9]; s += x1[-192] * w; t -= x2[ 192] * w; w = wp[10]; s += x1[-128] * w; t -= x2[ 128] * w; w = wp[11]; s += x1[- 64] * w; t -= x2[ 64] * w; w = wp[12]; s -= x1[ 0] * w; t += x2[ 0] * w; w = wp[13]; s -= x1[ 64] * w; t += x2[- 64] * w; w = wp[14]; s -= x1[ 128] * w; t += x2[-128] * w; w = wp[15]; s -= x1[ 192] * w; t += x2[-192] * w; wp += 16; *--a = t; a[(i+16)*2] = s; x1--; x2++; } { FLOAT8 s,t; t = x1[- 16] * wp[0]; s = x1[ -32] * wp[ 8]; t += (x1[- 48] - x1[ 16]) * wp[1]; s += x1[ -96] * wp[ 9]; t += (x1[- 80] + x1[ 48]) * wp[2]; s += x1[-160] * wp[10]; t += (x1[-112] - x1[ 80]) * wp[3]; s += x1[-224] * wp[11]; t += (x1[-144] + x1[112]) * wp[4]; s -= x1[ 32] * wp[12]; t += (x1[-176] - x1[144]) * wp[5]; s -= x1[ 96] * wp[13]; t += (x1[-208] + x1[176]) * wp[6]; s -= x1[ 160] * wp[14]; t += (x1[-240] - x1[208]) * wp[7]; s -= x1[ 224] * wp[15]; a[15] = t; a[-1] = s; } } /*-------------------------------------------------------------------*/ /* */ /* Function: Calculation of the MDCT */ /* In the case of long blocks (type 0,1,3) there are */ /* 36 coefficents in the time domain and 18 in the frequency */ /* domain. */ /* In the case of short blocks (type 2) there are 3 */ /* transformations with short length. This leads to 12 coefficents */ /* in the time and 6 in the frequency domain. In this case the */ /* results are stored side by side in the vector out[]. */ /* */ /* New layer3 */ /* */ /*-------------------------------------------------------------------*/ INLINE static void mdct_short(FLOAT8 *out, FLOAT8 *in) { int l; for ( l = 0; l < 3; l++ ) { FLOAT tc0,tc1,tc2,ts0,ts1,ts2; ts0 = in[5]; tc0 = in[3]; tc1 = ts0 + tc0; tc2 = ts0 - tc0; ts0 = in[2]; tc0 = in[0]; ts1 = ts0 + tc0; ts2 =-ts0 + tc0; tc0 = in[4]; ts0 = in[1]; out[3*0] = tc1 + tc0; out[3*5] =-ts1 + ts0; tc2 = tc2 * 0.86602540378443870761; ts1 = ts1 * 0.5 + ts0; out[3*1] = tc2-ts1; out[3*2] = tc2+ts1; tc1 = tc1 * 0.5 - tc0; ts2 = ts2 * 0.86602540378443870761; out[3*3] = tc1+ts2; out[3*4] = tc1-ts2; in += 6; out++; } } INLINE static void mdct_long(FLOAT8 *out, FLOAT8 *in) { #define inc(x) in[17-(x)] #define ins(x) in[8-(x)] const FLOAT8 c0=0.98480775301220802032, c1=0.64278760968653936292, c2=0.34202014332566882393; const FLOAT8 c3=0.93969262078590842791, c4=-0.17364817766693030343, c5=-0.76604444311897790243; FLOAT8 tc1 = inc(0)-inc(8),tc2 = (inc(1)-inc(7))*0.86602540378443870761, tc3 = inc(2)-inc(6), tc4 = inc(3)-inc(5); FLOAT8 tc5 = inc(0)+inc(8),tc6 = (inc(1)+inc(7))*0.5, tc7 = inc(2)+inc(6), tc8 = inc(3)+inc(5); FLOAT8 ts1 = ins(0)-ins(8),ts2 = (ins(1)-ins(7))*0.86602540378443870761, ts3 = ins(2)-ins(6), ts4 = ins(3)-ins(5); FLOAT8 ts5 = ins(0)+ins(8),ts6 = (ins(1)+ins(7))*0.5, ts7 = ins(2)+ins(6), ts8 = ins(3)+ins(5); FLOAT8 ct,st; ct = tc5+tc7+tc8+inc(1)+inc(4)+inc(7); out[0] = ct; ct = tc1*c0 + tc2 + tc3*c1 + tc4*c2; st = -ts5*c4 + ts6 - ts7*c5 + ts8*c3 + ins(4); out[1] = ct+st; out[2] = ct-st; ct = tc5*c3 + tc6 + tc7*c4 + tc8*c5 - inc(4); st = ts1*c2 + ts2 + ts3*c0 + ts4*c1; out[3] = ct+st; out[4] = ct-st; ct = (tc1-tc3-tc4)*0.86602540378443870761; st = (ts5+ts7-ts8)*0.5+ins(1)-ins(4)+ins(7); out[5] = ct+st; out[6] = ct-st; ct = -tc5*c5 - tc6 - tc7*c3 - tc8*c4 + inc(4); st = ts1*c1 + ts2 - ts3*c2 - ts4*c0; out[7] = ct+st; out[8] = ct-st; ct = tc1*c1 - tc2 - tc3*c2 + tc4*c0; st = -ts5*c5 + ts6 - ts7*c3 + ts8*c4 + ins(4); out[ 9] = ct+st; out[10] = ct-st; ct = (tc5+tc7+tc8)*0.5-inc(1)-inc(4)-inc(7); st = (ts1-ts3+ts4)*0.86602540378443870761; out[11] = ct+st; out[12] = ct-st; ct = tc1*c2 - tc2 + tc3*c0 - tc4*c1; st = ts5*c3 - ts6 + ts7*c4 - ts8*c5 - ins(4); out[13] = ct+st; out[14] = ct-st; ct = -tc5*c4 - tc6 - tc7*c5 - tc8*c3 + inc(4); st = ts1*c0 - ts2 + ts3*c1 - ts4*c2; out[15] = ct+st; out[16] = ct-st; st = ts5+ts7-ts8-ins(1)+ins(4)-ins(7); out[17] = st; } static const int order[] = { 0, 16, 8, 24, 4, 20, 12, 28, 2, 18, 10, 26, 6, 22, 14, 30, 1, 17, 9, 25, 5, 21, 13, 29, 3, 19, 11, 27, 7, 23, 15, 31 }; void mdct_init48(lame_global_flags *gfp) { int i, k; FLOAT8 sq; /* prepare the aliasing reduction butterflies */ for (k = 0; k < 8; k++) { /* This is table B.9: coefficients for aliasing reduction */ static const FLOAT8 c[8] = { -0.6,-0.535,-0.33,-0.185,-0.095,-0.041,-0.0142, -0.0037 }; sq = 1.0 + c[k] * c[k]; sq = sqrt(sq); ca[k] = c[k] / sq; cs[k] = 1.0 / sq; } /* type 0*/ for (i = 0; i < 36; i++) win[0][i] = sin(PI/36 * (i + 0.5)); /* type 1*/ for (i = 0; i < 18; i++) win[1][i] = win[0][i]; for (; i < 24; i++) win[1][i] = 1.0; for (; i < 30; i++) win[1][i] = cos(PI/12 * (i + 0.5)); for (; i < 36; i++) win[1][i] = 0.0; /* type 3*/ for (i = 0; i < 36; i++) win[3][i] = win[1][35 - i]; /* swap window data*/ for (k = 0; k < 4; k++) { FLOAT8 a; a = win[0][17-k]; win[0][17-k] = win[0][9+k]; win[0][9+k] = a; a = win[0][35-k]; win[0][35-k] = win[0][27+k]; win[0][27+k] = a; a = win[1][17-k]; win[1][17-k] = win[1][9+k]; win[1][9+k] = a; a = win[1][35-k]; win[1][35-k] = win[1][27+k]; win[1][27+k] = a; a = win[3][17-k]; win[3][17-k] = win[3][9+k]; win[3][9+k] = a; a = win[3][35-k]; win[3][35-k] = win[3][27+k]; win[3][27+k] = a; } for (i = 0; i < NL; i++) { win[0][i] *= cos((NL/4+0.5+i%9)*PI/NL) / SCALE/(NL/4); win[1][i] *= cos((NL/4+0.5+i%9)*PI/NL) / SCALE/(NL/4); win[3][i] *= cos((NL/4+0.5+i%9)*PI/NL) / SCALE/(NL/4); } for (i = NL/2; i < NL; i++) { win[0][i] *= -1; win[1][i] *= -1; win[3][i] *= -1; } for (i = 0; i < NL/4; i++) tantab_l[i] = tan((NL/4+0.5+i)*PI/NL); /* type 2(short)*/ for (i = 0; i < NS / 4; i++) { FLOAT8 w2 = cos(PI / NS * (i + 0.5)) * (4.0/NS) / SCALE; win[SHORT_TYPE][i] = tan(PI / NS * (i + 0.5)); tritab_s[i*2 ] = cos((0.5+2-i)*PI/NS) * w2; tritab_s[i*2+1] = sin((0.5+2-i)*PI/NS) * w2; } } void mdct_sub48(lame_global_flags *gfp, sample_t *w0, sample_t *w1, FLOAT8 mdct_freq[2][2][576], III_side_info_t *l3_side) { int gr, k, ch; sample_t *wk; static int init = 0; lame_internal_flags *gfc=gfp->internal_flags; FLOAT8 work[18]; if ( gfc->mdct_sub48_init == 0 ) { gfc->mdct_sub48_init=1; mdct_init48(gfp); init++; } wk = w0 + 286; /* thinking cache performance, ch->gr loop is better than gr->ch loop */ for (ch = 0; ch < gfc->stereo; ch++) { for (gr = 0; gr < gfc->mode_gr; gr++) { int band; FLOAT8 *mdct_enc = &mdct_freq[gr][ch][0]; gr_info *gi = &(l3_side->gr[gr].ch[ch].tt); FLOAT8 *samp = gfc->sb_sample[ch][1 - gr][0]; for (k = 0; k < 18 / 2; k++) { window_subband(wk, samp + 16); idct32(samp); window_subband(wk + 32, samp + 32+16); idct32(samp+32); samp += 64; wk += 64; /* * Compensate for inversion in the analysis filter */ for (band = 16-32; band < 0; band++) samp[band] *= -1; } /* apply filters on the polyphase filterbank outputs */ /* bands <= gfc->highpass_band will be zeroed out below */ /* bands >= gfc->lowpass_band will be zeroed out below */ if (gfc->filter_type==0) { for (band=gfc->highpass_start_band; band <= gfc->highpass_end_band; band++) { for (k=0; k<18; k++) gfc->sb_sample[ch][1-gr][k][order[band]]*=gfc->amp_highpass[band]; } for (band=gfc->lowpass_start_band; band <= gfc->lowpass_end_band; band++) { for (k=0; k<18; k++) gfc->sb_sample[ch][1-gr][k][order[band]]*=gfc->amp_lowpass[band]; } } /* * Perform imdct of 18 previous subband samples * + 18 current subband samples */ for (band = 0; band < 32; band++, mdct_enc += 18) { int type = gi->block_type; int band_swapped; band_swapped = order[band]; #ifdef ALLOW_MIXED if (gi->mixed_block_flag && band < 2) type = 0; #endif if (band >= gfc->lowpass_band || band <= gfc->highpass_band) { memset((char *)mdct_enc,0,18*sizeof(FLOAT8)); }else { if (type == SHORT_TYPE) { for (k = 2; k >= 0; --k) { FLOAT8 win1 = win[SHORT_TYPE][k]; FLOAT8 a, b; a = gfc->sb_sample[ch][gr][k+6][band_swapped] * win1 - gfc->sb_sample[ch][gr][11-k][band_swapped]; b = gfc->sb_sample[ch][gr][k+12][band_swapped] + gfc->sb_sample[ch][gr][17-k][band_swapped] * win1; work[k+3] = -b*tritab_s[k*2 ] + a * tritab_s[k*2+1]; work[k ] = b*tritab_s[k*2+1] + a * tritab_s[k*2 ]; a = gfc->sb_sample[ch][gr][k+12][band_swapped] * win1 - gfc->sb_sample[ch][gr][17-k][band_swapped]; b = gfc->sb_sample[ch][1-gr][k][band_swapped] + gfc->sb_sample[ch][1-gr][5-k][band_swapped] * win1; work[k+9] = -b*tritab_s[k*2 ] + a * tritab_s[k*2+1]; work[k+6] = b*tritab_s[k*2+1] + a * tritab_s[k*2 ]; a = gfc->sb_sample[ch][1-gr][k][band_swapped] * win1 - gfc->sb_sample[ch][1-gr][5-k][band_swapped]; b = gfc->sb_sample[ch][1-gr][k+6][band_swapped] + gfc->sb_sample[ch][1-gr][11-k][band_swapped] * win1; work[k+15] = -b*tritab_s[k*2 ] + a * tritab_s[k*2+1]; work[k+12] = b*tritab_s[k*2+1] + a * tritab_s[k*2 ]; } mdct_short(mdct_enc, work); } else { for (k = -NL/4; k < 0; k++) { FLOAT8 a, b; a = win[type][k+27] * gfc->sb_sample[ch][1-gr][k+9][band_swapped] + win[type][k+36] * gfc->sb_sample[ch][1-gr][8-k][band_swapped]; b = win[type][k+ 9] * gfc->sb_sample[ch][gr][k+9][band_swapped] - win[type][k+18] * gfc->sb_sample[ch][gr][8-k][band_swapped]; work[k+ 9] = a - b*tantab_l[k+9]; work[k+18] = a*tantab_l[k+9] + b; } mdct_long(mdct_enc, work); } } /* Perform aliasing reduction butterfly */ if (type != SHORT_TYPE) { if (band == 0) continue; for (k = 7; k >= 0; --k) { FLOAT8 bu,bd; bu = mdct_enc[k] * ca[k] + mdct_enc[-1-k] * cs[k]; bd = mdct_enc[k] * cs[k] - mdct_enc[-1-k] * ca[k]; mdct_enc[-1-k] = bu; mdct_enc[k] = bd; } } } } wk = w1 + 286; if (gfc->mode_gr == 1) { memcpy(gfc->sb_sample[ch][0], gfc->sb_sample[ch][1], 576 * sizeof(FLOAT8)); } } }