/* * 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 static FLOAT8 enwindow[] = { 3.5780907e-02,1.7876148e-02,3.134727e-03,2.457142e-03, 9.71317e-04, 2.18868e-04, 1.01566e-04, 1.3828e-05, 3.5758972e-02, 3.401756e-03, 9.83715e-04, 9.9182e-05, -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, -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, -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, -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, -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, -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, -9.54e-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, -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, -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, -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, -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, -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, -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, 3.0526638e-02, 4.638195e-03, 7.47204e-04, 4.9591e-05, 4.756451e-03, 2.1458e-05, -6.9618e-05, 2.384e-06 }; static FLOAT8 sb_sample[2][2][18][SBLIMIT]; static FLOAT8 mm[16][SBLIMIT - 1]; #define NS 12 #define NL 36 static const int all[] = {0,2,3,5,6,8,9,11,12,14,15,17}; static FLOAT8 ca[8], cs[8]; static FLOAT8 cos_s[NS / 2][NS / 2]; static FLOAT8 cos_l[(NL / 2) * 12 + (NL / 6) * 4 + (NL / 18) * 2]; static FLOAT8 win[4][36]; #define work (&win[2][4]) /************************************************************************ * * 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# * ************************************************************************/ static void window_subband(short *xk, FLOAT8 d[SBLIMIT], FLOAT8 *in) { int i; FLOAT8 s, t, *wp; wp = enwindow; { t = xk[255]; t += (xk[223] - xk[287]) * *wp++; t += (xk[191] + xk[319]) * *wp++; t += (xk[159] - xk[351]) * *wp++; t += (xk[127] + xk[383]) * *wp++; t += (xk[ 95] - xk[415]) * *wp++; t += (xk[ 63] + xk[447]) * *wp++; t += (xk[ 31] - xk[479]) * *wp++; in[15] = t; } for (i = 14; i >= 0; --i) { short *x1 = &xk[i]; short *x2 = &xk[-i]; FLOAT8 w; s = x2[270]; t = x1[240]; w = *wp++; s += x2[334] * w; t += x1[176] * w; w = *wp++; s += x2[398] * w; t += x1[112] * w; w = *wp++; s += x2[462] * w; t += x1[ 48] * w; w = *wp++; s += x2[ 14] * w; t += x1[496] * w; w = *wp++; s += x2[ 78] * w; t += x1[432] * w; w = *wp++; s += x2[142] * w; t += x1[368] * w; w = *wp++; s += x2[206] * w; t += x1[304] * w; w = *wp++; s += x1[ 16] * w; t -= x2[494] * w; w = *wp++; s += x1[ 80] * w; t -= x2[430] * w; w = *wp++; s += x1[144] * w; t -= x2[366] * w; w = *wp++; s += x1[208] * w; t -= x2[302] * w; w = *wp++; s -= x1[272] * w; t += x2[238] * w; w = *wp++; s -= x1[336] * w; t += x2[174] * w; w = *wp++; s -= x1[400] * w; t += x2[110] * w; w = *wp++; s -= x1[464] * w; t += x2[ 46] * w; in[30 - i] = s; in[i] = t; } { s = xk[239]; s += xk[175] * *wp++; s += xk[111] * *wp++; s += xk[ 47] * *wp++; s -= xk[303] * *wp++; s -= xk[367] * *wp++; s -= xk[431] * *wp++; s -= xk[495] * *wp++; /* in[-1] = s; */ } in++; wp = &mm[0][0]; for (i = 15; i >= 0; --i) { int j; FLOAT8 s0 = s; /* mm[i][0] is always 1 */ FLOAT8 s1 = t * *wp++; for (j = 14; j >= 0; j--) { s0 += *wp++ * *in++; s1 += *wp++ * *in++; } in -= 30; d[i ] = s0 + s1; d[31 - i] = s0 - s1; } } /*-------------------------------------------------------------------*/ /* */ /* 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 */ /* */ /*-------------------------------------------------------------------*/ static void mdct_short(FLOAT8 *out, FLOAT8 *in) { int m; for (m = NS / 2 - 1; m >= 0; --m) { int l; FLOAT8 a0, a1, a2, a3, a4, a5; a0 = cos_s[m][0]; a1 = cos_s[m][1]; a2 = cos_s[m][2]; a3 = cos_s[m][3]; a4 = cos_s[m][4]; a5 = cos_s[m][5]; for (l = 2; l >= 0; l--) { out[3 * m + l] = a0 * in[6 * l ] + a1 * in[6 * l + 1] + a2 * in[6 * l + 2] + a3 * in[6 * l + 3] + a4 * in[6 * l + 4] + a5 * in[6 * l + 5]; } } } static void mdct_long(FLOAT8 *out, FLOAT8 *in) { FLOAT8 s0, s1, s2, s3, s4, s5; int j = sizeof(all) / sizeof(int) - 1; FLOAT8 *cos_l0 = cos_l; do { out[all[j]] = in[ 0] * cos_l0[ 0] + in[ 1] * cos_l0[ 1] + in[ 2] * cos_l0[ 2] + in[ 3] * cos_l0[ 3] + in[ 4] * cos_l0[ 4] + in[ 5] * cos_l0[ 5] + in[ 6] * cos_l0[ 6] + in[ 7] * cos_l0[ 7] + in[ 8] * cos_l0[ 8] + in[ 9] * cos_l0[ 9] + in[10] * cos_l0[10] + in[11] * cos_l0[11] + in[12] * cos_l0[12] + in[13] * cos_l0[13] + in[14] * cos_l0[14] + in[15] * cos_l0[15] + in[16] * cos_l0[16] + in[17] * cos_l0[17]; cos_l0 += 18; } while (--j >= 0); s0 = in[0] + in[ 5] + in[15]; s1 = in[1] + in[ 4] + in[16]; s2 = in[2] + in[ 3] + in[17]; s3 = in[6] - in[ 9] + in[14]; s4 = in[7] - in[10] + in[13]; s5 = in[8] - in[11] + in[12]; /* 16 */ out[16] = s0 * cos_l0[0] + s1 * cos_l0[1] + s2 * cos_l0[2] + s3 * cos_l0[3] + s4 * cos_l0[4] + s5 * cos_l0[5]; cos_l0 += 6; /* 10 */ out[10] = s0 * cos_l0[0] + s1 * cos_l0[1] + s2 * cos_l0[2] + s3 * cos_l0[3] + s4 * cos_l0[4] + s5 * cos_l0[5]; cos_l0 += 6; /* 7 */ out[7] = s0 * cos_l0[0] + s1 * cos_l0[1] + s2 * cos_l0[2] + s3 * cos_l0[3] + s4 * cos_l0[4] + s5 * cos_l0[5]; cos_l0 += 6; /* 1 */ out[1] = s0 * cos_l0[0] + s1 * cos_l0[1] + s2 * cos_l0[2] + s3 * cos_l0[3] + s4 * cos_l0[4] + s5 * cos_l0[5]; cos_l0 += 6; s0 = s0 - s1 + s5; s2 = s2 - s3 - s4; /* 13 */ out[13] = s0 * cos_l0[0] + s2 * cos_l0[1]; /* 4 */ out[4] = s0 * cos_l0[2] + s2 * cos_l0[3]; } void mdct_sub48(lame_global_flags *gfp, short *w0, short *w1, FLOAT8 mdct_freq[2][2][576], III_side_info_t *l3_side) { int gr, k, ch; short *wk; static int init = 0; if ( init == 0 ) { void mdct_init48(void); mdct_init48(); init++; } wk = w0; /* thinking cache performance, ch->gr loop is better than gr->ch loop */ for (ch = 0; ch < gfp->stereo; ch++) { for (gr = 0; gr < gfp->mode_gr; gr++) { int band; FLOAT8 *mdct_enc = mdct_freq[gr][ch]; gr_info *gi = &(l3_side->gr[gr].ch[ch].tt); FLOAT8 *samp = sb_sample[ch][1 - gr][0]; for (k = 0; k < 18 / 2; k++) { window_subband(wk, samp, work); window_subband(wk + 32, samp + 32, work); /* * Compensate for inversion in the analysis filter */ for (band = 1; band < 32; band += 2) samp[band + 32] *= -1.0; samp += 64; wk += 64; } /* apply filters on the polyphase filterbank outputs */ /* bands <= gfp->highpass_band will be zeroed out below */ /* bands >= gfp->lowpass_band will be zeroed out below */ if (gfp->filter_type==0) { FLOAT8 amp,freq; for (band=gfp->highpass_band+1; band < gfp->lowpass_band ; band++) { freq = band/31.0; if (gfp->lowpass1 < freq && freq < gfp->lowpass2) { amp = cos((PI/2)*(gfp->lowpass1-freq)/(gfp->lowpass2-gfp->lowpass1)); for (k=0; k<18; k++) sb_sample[ch][1-gr][k][band]*=amp; } if (gfp->highpass1 < freq && freq < gfp->highpass2) { amp = cos((PI/2)*(gfp->highpass2-freq)/(gfp->highpass2-gfp->highpass1)); for (k=0; k<18; k++) sb_sample[ch][1-gr][k][band]*=amp; } } } /* * 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; #ifdef ALLOW_MIXED if (gi->mixed_block_flag && band < 2) type = 0; #endif if (band >= gfp->lowpass_band || band <= gfp->highpass_band) { memset((char *)mdct_enc,0,18*sizeof(FLOAT8)); }else { if (type == SHORT_TYPE) { for (k = 2; k >= 0; --k) { FLOAT8 w1 = win[SHORT_TYPE][k]; work[k] = sb_sample[ch][gr][k+6][band] * w1 - sb_sample[ch][gr][11-k][band]; work[k+3] = sb_sample[ch][gr][k+12][band] + sb_sample[ch][gr][17-k][band] * w1; work[k+6] = sb_sample[ch][gr][k+12][band] * w1 - sb_sample[ch][gr][17-k][band]; work[k+9] = sb_sample[ch][1-gr][k][band] + sb_sample[ch][1-gr][5-k][band] * w1; work[k+12] = sb_sample[ch][1-gr][k][band] * w1 - sb_sample[ch][1-gr][5-k][band]; work[k+15] = sb_sample[ch][1-gr][k+6][band] + sb_sample[ch][1-gr][11-k][band] * w1; } mdct_short(mdct_enc, work); } else { for (k = 8; k >= 0; --k) { work[k] = win[type][k ] * sb_sample[ch][gr][k ][band] - win[type][k+9] * sb_sample[ch][gr][17-k][band]; work[9+k] = win[type][k+18] * sb_sample[ch][1-gr][k ][band] + win[type][k+27] * sb_sample[ch][1-gr][17-k][band]; } 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; if (gfp->mode_gr == 1) { memcpy(sb_sample[ch][0], sb_sample[ch][1], 576 * sizeof(FLOAT8)); } } } void mdct_init48(void) { int i, k, m; FLOAT8 sq; FLOAT8 max; /* 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]; sq = 4.0 / NL; { FLOAT8 *cos_l0 = cos_l; static const int d3[] = {1,7,10,16}; static const int d9[] = {4,13}; int j = sizeof(all) / sizeof(int) - 1; do { m = all[j]; for (k = 0; k < NL / 4; k++) { *cos_l0++ = sq * cos((PI / (4 * NL)) * (2 * m + 1) * (4 * k + 2 + NL)); } for (k = 0; k < NL / 4; k++) { *cos_l0++ = sq * cos((PI / (4 * NL)) * (2 * m + 1) * (4 * k + 2 + NL * 3)); } } while (--j >= 0); j = sizeof(d3) / sizeof(int) - 1; do { m = d3[j]; for (k = 0; k < 3; k++) { *cos_l0++ = sq * cos((PI / (4 * NL)) * (2 * m + 1) * (4 * k + 2 + NL)); } for (k = 6; k < 9; k++) { *cos_l0++ = sq * cos((PI / (4 * NL)) * (2 * m + 1) * (4 * k + 2 + NL)); } } while (--j >= 0); j = sizeof(d9) / sizeof(int) - 1; do { m = d9[j]; *cos_l0++ = sq * cos((PI / (4 * NL)) * (2 * m + 1) * (2 + NL)); *cos_l0++ = sq * cos((PI / (4 * NL)) * (2 * m + 1) * (4 * 2 + 2 + NL)); } while (--j >= 0); } max = enwindow[256 - 8]; { FLOAT8 *wp = enwindow; FLOAT8 *wr = enwindow; FLOAT8 mmax[32 - 1]; { FLOAT8 w = *wp++; mmax[15] = w / max; for (k = 0; k < 7; k++) { *wr++ = *wp++ / w; } } for (i = 14; i >= 0; --i) { FLOAT8 w = *wp++; mmax[i] = mmax[30 - i] = w / max; for (k = 0; k < 15; k++) { *wr++ = *wp++ / w; } } { wp++; for (k = 0; k < 7; k++) { *wr++ = *wp++ / max; } } wp = &mm[0][0]; for (i = 15; i >= 0; --i) { for (k = 1; k < 32; k++) { *wp++ = cos((2 * i + 1) * k * PI/64) * mmax[k - 1]; } } } /* 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 < 36; i++) { win[0][i] *= max / SCALE; win[1][i] *= max / SCALE; win[3][i] *= max / SCALE; } /* type 2(short)*/ sq = 4.0 / NS; for (i = 0; i < NS / 4; i++) { FLOAT8 w2 = cos(PI/12 * (i + 0.5)) * max / SCALE * sq; win[SHORT_TYPE][i] = tan(PI/12 * (i + 0.5)); for (m = 0; m < NS / 2; m++) { cos_s[m][i] = w2 * cos((PI / (4 * NS)) * (2 * m + 1) * (4 * i + 2 + NS)); cos_s[m][i + NS / 4] = w2 * cos((PI / (4 * NS)) * (2 * m + 1) * (4 * i + 2 + NS * 3)); } } }