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-rw-r--r--src/libac3/imdct.c661
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diff --git a/src/libac3/imdct.c b/src/libac3/imdct.c
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+++ b/src/libac3/imdct.c
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+/*
+ * imdct.c
+ *
+ * Copyright (C) Aaron Holtzman - May 1999
+ *
+ * This file is part of ac3dec, a free Dolby AC-3 stream decoder.
+ *
+ * ac3dec 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, or (at your option)
+ * any later version.
+ *
+ * ac3dec 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 GNU Make; see the file COPYING. If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <math.h>
+#include "ac3.h"
+#include "ac3_internal.h"
+
+#include "downmix.h"
+#include "imdct.h"
+#include "srfft.h"
+
+#define N 512
+
+/* static complex_t buf[128]; */
+//static complex_t buf[128] __attribute__((aligned(16)));
+complex_t buf[128] __attribute__((aligned(16)));
+
+/* Delay buffer for time domain interleaving */
+static float delay[6][256];
+static float delay1[6][256];
+
+/* Twiddle factors for IMDCT */
+static float xcos1[128] __attribute__((aligned(16)));
+static float xsin1[128] __attribute__((aligned(16)));
+
+/* more twiddle factors for IMDCT */
+static float xcos2[64];
+static float xsin2[64];
+
+/* Windowing function for Modified DCT - Thank you acroread */
+//static float window[] = {
+float window[] = {
+ 0.00014, 0.00024, 0.00037, 0.00051, 0.00067, 0.00086, 0.00107, 0.00130,
+ 0.00157, 0.00187, 0.00220, 0.00256, 0.00297, 0.00341, 0.00390, 0.00443,
+ 0.00501, 0.00564, 0.00632, 0.00706, 0.00785, 0.00871, 0.00962, 0.01061,
+ 0.01166, 0.01279, 0.01399, 0.01526, 0.01662, 0.01806, 0.01959, 0.02121,
+ 0.02292, 0.02472, 0.02662, 0.02863, 0.03073, 0.03294, 0.03527, 0.03770,
+ 0.04025, 0.04292, 0.04571, 0.04862, 0.05165, 0.05481, 0.05810, 0.06153,
+ 0.06508, 0.06878, 0.07261, 0.07658, 0.08069, 0.08495, 0.08935, 0.09389,
+ 0.09859, 0.10343, 0.10842, 0.11356, 0.11885, 0.12429, 0.12988, 0.13563,
+ 0.14152, 0.14757, 0.15376, 0.16011, 0.16661, 0.17325, 0.18005, 0.18699,
+ 0.19407, 0.20130, 0.20867, 0.21618, 0.22382, 0.23161, 0.23952, 0.24757,
+ 0.25574, 0.26404, 0.27246, 0.28100, 0.28965, 0.29841, 0.30729, 0.31626,
+ 0.32533, 0.33450, 0.34376, 0.35311, 0.36253, 0.37204, 0.38161, 0.39126,
+ 0.40096, 0.41072, 0.42054, 0.43040, 0.44030, 0.45023, 0.46020, 0.47019,
+ 0.48020, 0.49022, 0.50025, 0.51028, 0.52031, 0.53033, 0.54033, 0.55031,
+ 0.56026, 0.57019, 0.58007, 0.58991, 0.59970, 0.60944, 0.61912, 0.62873,
+ 0.63827, 0.64774, 0.65713, 0.66643, 0.67564, 0.68476, 0.69377, 0.70269,
+ 0.71150, 0.72019, 0.72877, 0.73723, 0.74557, 0.75378, 0.76186, 0.76981,
+ 0.77762, 0.78530, 0.79283, 0.80022, 0.80747, 0.81457, 0.82151, 0.82831,
+ 0.83496, 0.84145, 0.84779, 0.85398, 0.86001, 0.86588, 0.87160, 0.87716,
+ 0.88257, 0.88782, 0.89291, 0.89785, 0.90264, 0.90728, 0.91176, 0.91610,
+ 0.92028, 0.92432, 0.92822, 0.93197, 0.93558, 0.93906, 0.94240, 0.94560,
+ 0.94867, 0.95162, 0.95444, 0.95713, 0.95971, 0.96217, 0.96451, 0.96674,
+ 0.96887, 0.97089, 0.97281, 0.97463, 0.97635, 0.97799, 0.97953, 0.98099,
+ 0.98236, 0.98366, 0.98488, 0.98602, 0.98710, 0.98811, 0.98905, 0.98994,
+ 0.99076, 0.99153, 0.99225, 0.99291, 0.99353, 0.99411, 0.99464, 0.99513,
+ 0.99558, 0.99600, 0.99639, 0.99674, 0.99706, 0.99736, 0.99763, 0.99788,
+ 0.99811, 0.99831, 0.99850, 0.99867, 0.99882, 0.99895, 0.99908, 0.99919,
+ 0.99929, 0.99938, 0.99946, 0.99953, 0.99959, 0.99965, 0.99969, 0.99974,
+ 0.99978, 0.99981, 0.99984, 0.99986, 0.99988, 0.99990, 0.99992, 0.99993,
+ 0.99994, 0.99995, 0.99996, 0.99997, 0.99998, 0.99998, 0.99998, 0.99999,
+ 0.99999, 0.99999, 0.99999, 1.00000, 1.00000, 1.00000, 1.00000, 1.00000,
+ 1.00000, 1.00000, 1.00000, 1.00000, 1.00000, 1.00000, 1.00000, 1.00000
+};
+
+//static const int pm128[128] =
+const int pm128[128] =
+{
+ 0, 16, 32, 48, 64, 80, 96, 112, 8, 40, 72, 104, 24, 56, 88, 120,
+ 4, 20, 36, 52, 68, 84, 100, 116, 12, 28, 44, 60, 76, 92, 108, 124,
+ 2, 18, 34, 50, 66, 82, 98, 114, 10, 42, 74, 106, 26, 58, 90, 122,
+ 6, 22, 38, 54, 70, 86, 102, 118, 14, 46, 78, 110, 30, 62, 94, 126,
+ 1, 17, 33, 49, 65, 81, 97, 113, 9, 41, 73, 105, 25, 57, 89, 121,
+ 5, 21, 37, 53, 69, 85, 101, 117, 13, 29, 45, 61, 77, 93, 109, 125,
+ 3, 19, 35, 51, 67, 83, 99, 115, 11, 43, 75, 107, 27, 59, 91, 123,
+ 7, 23, 39, 55, 71, 87, 103, 119, 15, 31, 47, 63, 79, 95, 111, 127
+};
+
+static const int pm64[64] =
+{
+ 0, 8, 16, 24, 32, 40, 48, 56,
+ 4, 20, 36, 52, 12, 28, 44, 60,
+ 2, 10, 18, 26, 34, 42, 50, 58,
+ 6, 14, 22, 30, 38, 46, 54, 62,
+ 1, 9, 17, 25, 33, 41, 49, 57,
+ 5, 21, 37, 53, 13, 29, 45, 61,
+ 3, 11, 19, 27, 35, 43, 51, 59,
+ 7, 23, 39, 55, 15, 31, 47, 63
+};
+
+
+void imdct_init (void)
+ {
+ int i;
+ float scale = 255.99609372;
+
+ /* Twiddle factors to turn IFFT into IMDCT */
+
+ for (i=0; i < 128; i++) {
+ xcos1[i] = cos(2.0f * M_PI * (8*i+1)/(8*N)) * scale;
+ xsin1[i] = sin(2.0f * M_PI * (8*i+1)/(8*N)) * scale;
+ }
+
+ // More twiddle factors to turn IFFT into IMDCT */
+ for (i=0; i < 64; i++) {
+ xcos2[i] = cos(2.0f * M_PI * (8*i+1)/(4*N)) * scale;
+ xsin2[i] = sin(2.0f * M_PI * (8*i+1)/(4*N)) * scale;
+ }
+}
+
+
+void imdct_do_256 (float data[],float delay[])
+{
+ int i, j, k;
+ int p, q;
+
+ float tmp_a_i;
+ float tmp_a_r;
+
+ float *data_ptr;
+ float *delay_ptr;
+ float *window_ptr;
+
+ complex_t *buf1, *buf2;
+
+ buf1 = &buf[0];
+ buf2 = &buf[64];
+
+// Pre IFFT complex multiply plus IFFT complex conjugate
+ for (k=0; k<64; k++) {
+ /* X1[k] = X[2*k] */
+ /* X2[k] = X[2*k+1] */
+
+ j = pm64[k];
+ p = 2 * (128-2*j-1);
+ q = 2 * (2 * j);
+
+ /* Z1[k] = (X1[128-2*k-1] + j * X1[2*k]) * (xcos2[k] + j * xsin2[k]); */
+ buf1[k].re = data[p] * xcos2[j] - data[q] * xsin2[j];
+ buf1[k].im = -1.0f * (data[q] * xcos2[j] + data[p] * xsin2[j]);
+ /* Z2[k] = (X2[128-2*k-1] + j * X2[2*k]) * (xcos2[k] + j * xsin2[k]); */
+ buf2[k].re = data[p + 1] * xcos2[j] - data[q + 1] * xsin2[j];
+ buf2[k].im = -1.0f * ( data[q + 1] * xcos2[j] + data[p + 1] * xsin2[j]);
+ }
+
+ fft_64p(&buf1[0]);
+ fft_64p(&buf2[0]);
+
+#ifdef DEBUG
+ //DEBUG FFT
+#if 0
+ printf ("Post FFT, buf1\n");
+ for (i=0; i < 64; i++)
+ printf("%d %f %f\n", i, buf_1[i].re, buf_1[i].im);
+ printf ("Post FFT, buf2\n");
+ for (i=0; i < 64; i++)
+ printf("%d %f %f\n", i, buf_2[i].re, buf_2[i].im);
+#endif
+#endif
+
+
+ // Post IFFT complex multiply
+ for( i=0; i < 64; i++) {
+ tmp_a_r = buf1[i].re;
+ tmp_a_i = -buf1[i].im;
+ buf1[i].re =(tmp_a_r * xcos2[i]) - (tmp_a_i * xsin2[i]);
+ buf1[i].im =(tmp_a_r * xsin2[i]) + (tmp_a_i * xcos2[i]);
+ tmp_a_r = buf2[i].re;
+ tmp_a_i = -buf2[i].im;
+ buf2[i].re =(tmp_a_r * xcos2[i]) - (tmp_a_i * xsin2[i]);
+ buf2[i].im =(tmp_a_r * xsin2[i]) + (tmp_a_i * xcos2[i]);
+ }
+
+ data_ptr = data;
+ delay_ptr = delay;
+ window_ptr = window;
+
+ /* Window and convert to real valued signal */
+ for(i=0; i< 64; i++) {
+ *data_ptr++ = -buf1[i].im * *window_ptr++ + *delay_ptr++;
+ *data_ptr++ = buf1[64-i-1].re * *window_ptr++ + *delay_ptr++;
+ }
+
+ for(i=0; i< 64; i++) {
+ *data_ptr++ = -buf1[i].re * *window_ptr++ + *delay_ptr++;
+ *data_ptr++ = buf1[64-i-1].im * *window_ptr++ + *delay_ptr++;
+ }
+
+ delay_ptr = delay;
+
+ for(i=0; i< 64; i++) {
+ *delay_ptr++ = -buf2[i].re * *--window_ptr;
+ *delay_ptr++ = buf2[64-i-1].im * *--window_ptr;
+ }
+
+ for(i=0; i< 64; i++) {
+ *delay_ptr++ = buf2[i].im * *--window_ptr;
+ *delay_ptr++ = -buf2[64-i-1].re * *--window_ptr;
+ }
+}
+
+
+/**
+ *
+ **/
+
+void imdct_do_256_nol (float data[], float delay[])
+{
+ int i, j, k;
+ int p, q;
+
+ float tmp_a_i;
+ float tmp_a_r;
+
+ float *data_ptr;
+ float *delay_ptr;
+ float *window_ptr;
+
+ complex_t *buf1, *buf2;
+
+ buf1 = &buf[0];
+ buf2 = &buf[64];
+
+ /* Pre IFFT complex multiply plus IFFT cmplx conjugate */
+ for(k=0; k<64; k++) {
+ /* X1[k] = X[2*k] */
+ /* X2[k] = X[2*k+1] */
+ j = pm64[k];
+ p = 2 * (128-2*j-1);
+ q = 2 * (2 * j);
+
+ /* Z1[k] = (X1[128-2*k-1] + j * X1[2*k]) * (xcos2[k] + j * xsin2[k]); */
+ buf1[k].re = data[p] * xcos2[j] - data[q] * xsin2[j];
+ buf1[k].im = -1.0f * (data[q] * xcos2[j] + data[p] * xsin2[j]);
+ /* Z2[k] = (X2[128-2*k-1] + j * X2[2*k]) * (xcos2[k] + j * xsin2[k]); */
+ buf2[k].re = data[p + 1] * xcos2[j] - data[q + 1] * xsin2[j];
+ buf2[k].im = -1.0f * ( data[q + 1] * xcos2[j] + data[p + 1] * xsin2[j]);
+ }
+
+
+ fft_64p(&buf1[0]);
+ fft_64p(&buf2[0]);
+
+#ifdef DEBUG
+ //DEBUG FFT
+#if 0
+ printf("Post FFT, buf1\n");
+ for (i=0; i < 64; i++)
+ printf("%d %f %f\n", i, buf_1[i].re, buf_1[i].im);
+ printf("Post FFT, buf2\n");
+ for (i=0; i < 64; i++)
+ printf("%d %f %f\n", i, buf_2[i].re, buf_2[i].im);
+#endif
+#endif
+
+ /* Post IFFT complex multiply */
+ for( i=0; i < 64; i++) {
+ /* y1[n] = z1[n] * (xcos2[n] + j * xs in2[n]) ; */
+ tmp_a_r = buf1[i].re;
+ tmp_a_i = -buf1[i].im;
+ buf1[i].re =(tmp_a_r * xcos2[i]) - (tmp_a_i * xsin2[i]);
+ buf1[i].im =(tmp_a_r * xsin2[i]) + (tmp_a_i * xcos2[i]);
+ /* y2[n] = z2[n] * (xcos2[n] + j * xsin2[n]) ; */
+ tmp_a_r = buf2[i].re;
+ tmp_a_i = -buf2[i].im;
+ buf2[i].re =(tmp_a_r * xcos2[i]) - (tmp_a_i * xsin2[i]);
+ buf2[i].im =(tmp_a_r * xsin2[i]) + (tmp_a_i * xcos2[i]);
+ }
+
+ data_ptr = data;
+ delay_ptr = delay;
+ window_ptr = window;
+
+ /* Window and convert to real valued signal, no overlap */
+ for(i=0; i< 64; i++) {
+ *data_ptr++ = -buf1[i].im * *window_ptr++;
+ *data_ptr++ = buf1[64-i-1].re * *window_ptr++;
+ }
+
+ for(i=0; i< 64; i++) {
+ *data_ptr++ = -buf1[i].re * *window_ptr++ + *delay_ptr++;
+ *data_ptr++ = buf1[64-i-1].im * *window_ptr++ + *delay_ptr++;
+ }
+
+ delay_ptr = delay;
+
+ for(i=0; i< 64; i++) {
+ *delay_ptr++ = -buf2[i].re * *--window_ptr;
+ *delay_ptr++ = buf2[64-i-1].im * *--window_ptr;
+ }
+
+ for(i=0; i< 64; i++) {
+ *delay_ptr++ = buf2[i].im * *--window_ptr;
+ *delay_ptr++ = -buf2[64-i-1].re * *--window_ptr;
+ }
+}
+
+//FIXME remove - for timing code
+///#include <sys/time.h>
+//FIXME remove
+
+
+void imdct_do_512 (float data[], float delay[])
+{
+ int i, j;
+ float tmp_a_r, tmp_a_i;
+ float *data_ptr;
+ float *delay_ptr;
+ float *window_ptr;
+
+// 512 IMDCT with source and dest data in 'data'
+// Pre IFFT complex multiply plus IFFT complex conjugate
+
+ for( i=0; i < 128; i++) {
+ j = pm128[i];
+ //a = (data[256-2*j-1] - data[2*j]) * (xcos1[j] + xsin1[j]);
+ //c = data[2*j] * xcos1[j];
+ //b = data[256-2*j-1] * xsin1[j];
+ //buf1[i].re = a - b + c;
+ //buf1[i].im = b + c;
+ buf[i].re = (data[256-2*j-1] * xcos1[j]) - (data[2*j] * xsin1[j]);
+ buf[i].im = -1.0 * (data[2*j] * xcos1[j] + data[256-2*j-1] * xsin1[j]);
+ }
+
+ fft_128p (&buf[0]);
+
+// Post IFFT complex multiply plus IFFT complex conjugate
+ for (i=0; i < 128; i++) {
+ tmp_a_r = buf[i].re;
+ tmp_a_i = buf[i].im;
+ //a = (tmp_a_r - tmp_a_i) * (xcos1[j] + xsin1[j]);
+ //b = tmp_a_r * xsin1[j];
+ //c = tmp_a_i * xcos1[j];
+ //buf[j].re = a - b + c;
+ //buf[j].im = b + c;
+ buf[i].re =(tmp_a_r * xcos1[i]) + (tmp_a_i * xsin1[i]);
+ buf[i].im =(tmp_a_r * xsin1[i]) - (tmp_a_i * xcos1[i]);
+ }
+
+ data_ptr = data;
+ delay_ptr = delay;
+ window_ptr = window;
+
+// Window and convert to real valued signal
+ for (i=0; i< 64; i++) {
+ *data_ptr++ = -buf[64+i].im * *window_ptr++ + *delay_ptr++;
+ *data_ptr++ = buf[64-i-1].re * *window_ptr++ + *delay_ptr++;
+ }
+
+ for(i=0; i< 64; i++) {
+ *data_ptr++ = -buf[i].re * *window_ptr++ + *delay_ptr++;
+ *data_ptr++ = buf[128-i-1].im * *window_ptr++ + *delay_ptr++;
+ }
+
+// The trailing edge of the window goes into the delay line
+ delay_ptr = delay;
+
+ for(i=0; i< 64; i++) {
+ *delay_ptr++ = -buf[64+i].re * *--window_ptr;
+ *delay_ptr++ = buf[64-i-1].im * *--window_ptr;
+ }
+
+ for(i=0; i<64; i++) {
+ *delay_ptr++ = buf[i].im * *--window_ptr;
+ *delay_ptr++ = -buf[128-i-1].re * *--window_ptr;
+ }
+}
+
+
+void imdct_do_512_nol (float data[], float delay[])
+{
+ int i, j;
+
+ float tmp_a_i;
+ float tmp_a_r;
+
+ float *data_ptr;
+ float *delay_ptr;
+ float *window_ptr;
+
+ //
+ // 512 IMDCT with source and dest data in 'data'
+ //
+
+ // Pre IFFT complex multiply plus IFFT cmplx conjugate
+
+ for( i=0; i < 128; i++) {
+ /* z[i] = (X[256-2*i-1] + j * X[2*i]) * (xcos1[i] + j * xsin1[i]) */
+ j = pm128[i];
+ //a = (data[256-2*j-1] - data[2*j]) * (xcos1[j] + xsin1[j]);
+ //c = data[2*j] * xcos1[j];
+ //b = data[256-2*j-1] * xsin1[j];
+ //buf1[i].re = a - b + c;
+
+ //buf1[i].im = b + c;
+ buf[i].re = (data[256-2*j-1] * xcos1[j]) - (data[2*j] * xsin1[j]);
+ buf[i].im = -1.0 * (data[2*j] * xcos1[j] + data[256-2*j-1] * xsin1[j]);
+ }
+
+ fft_128p (&buf[0]);
+
+ /* Post IFFT complex multiply plus IFFT complex conjugate*/
+ for (i=0; i < 128; i++) {
+ /* y[n] = z[n] * (xcos1[n] + j * xsin1[n]) ; */
+ /* int j1 = i; */
+ tmp_a_r = buf[i].re;
+ tmp_a_i = buf[i].im;
+ //a = (tmp_a_r - tmp_a_i) * (xcos1[j] + xsin1[j]);
+ //b = tmp_a_r * xsin1[j];
+ //c = tmp_a_i * xcos1[j];
+ //buf[j].re = a - b + c;
+ //buf[j].im = b + c;
+ buf[i].re =(tmp_a_r * xcos1[i]) + (tmp_a_i * xsin1[i]);
+ buf[i].im =(tmp_a_r * xsin1[i]) - (tmp_a_i * xcos1[i]);
+ }
+
+ data_ptr = data;
+ delay_ptr = delay;
+ window_ptr = window;
+
+ /* Window and convert to real valued signal, no overlap here*/
+ for (i=0; i< 64; i++) {
+ *data_ptr++ = -buf[64+i].im * *window_ptr++;
+ *data_ptr++ = buf[64-i-1].re * *window_ptr++;
+ }
+
+ for(i=0; i< 64; i++) {
+ *data_ptr++ = -buf[i].re * *window_ptr++;
+ *data_ptr++ = buf[128-i-1].im * *window_ptr++;
+ }
+
+ /* The trailing edge of the window goes into the delay line */
+ delay_ptr = delay;
+
+ for(i=0; i< 64; i++) {
+ *delay_ptr++ = -buf[64+i].re * *--window_ptr;
+ *delay_ptr++ = buf[64-i-1].im * *--window_ptr;
+ }
+
+ for(i=0; i<64; i++) {
+ *delay_ptr++ = buf[i].im * *--window_ptr;
+ *delay_ptr++ = -buf[128-i-1].re * *--window_ptr;
+ }
+}
+
+void imdct (bsi_t *bsi,audblk_t *audblk, stream_samples_t samples, int16_t *s16_samples, dm_par_t* dm_par)
+{
+ int i;
+ int doable = 0;
+ float *center=NULL, *left, *right, *left_sur, *right_sur;
+ float *delay_left, *delay_right;
+ float *delay1_left, *delay1_right, *delay1_center, *delay1_sr, *delay1_sl;
+ float right_tmp, left_tmp;
+ void (*do_imdct)(float data[], float deley[]);
+
+ // test if dm in frequency is doable
+ if (!(doable = audblk->blksw[0]))
+ do_imdct = imdct_do_512;
+ else
+ do_imdct = imdct_do_256;
+
+ // downmix in the frequency domain if all the channels
+ // use the same imdct
+ for (i=0; i < bsi->nfchans; i++) {
+ if (doable != audblk->blksw[i]) {
+ do_imdct = NULL;
+ break;
+ }
+ }
+
+ if (do_imdct) {
+ //dowmix first and imdct
+ switch(bsi->acmod) {
+ case 7: // 3/2
+ downmix_3f_2r_to_2ch (samples[0], dm_par);
+ break;
+ case 6: // 2/2
+ downmix_2f_2r_to_2ch (samples[0], dm_par);
+ break;
+ case 5: // 3/1
+ downmix_3f_1r_to_2ch (samples[0], dm_par);
+ break;
+ case 4: // 2/1
+ downmix_2f_1r_to_2ch (samples[0], dm_par);
+ break;
+ case 3: // 3/0
+ downmix_3f_0r_to_2ch (samples[0], dm_par);
+ break;
+ case 2:
+ break;
+ default: // 1/0
+ if (bsi->acmod == 1)
+ center = samples[0];
+ else if (bsi->acmod == 0)
+ center = samples[ac3_config.dual_mono_ch_sel];
+ do_imdct(center, delay[0]); // no downmix
+
+ stream_sample_1ch_to_s16 (s16_samples, center);
+
+ return;
+ //goto done;
+ break;
+ }
+
+ do_imdct (samples[0], delay[0]);
+ do_imdct (samples[1], delay[1]);
+ stream_sample_2ch_to_s16(s16_samples, samples[0], samples[1]);
+
+ } else { //imdct and then dowmix
+ // delay and samples should be saved and mixed
+ //fprintf(stderr, "time domain downmix\n");
+ for (i=0; i<bsi->nfchans; i++) {
+ if (audblk->blksw[i])
+ imdct_do_256_nol (samples[i],delay1[i]);
+ else
+ imdct_do_512_nol (samples[i],delay1[i]);
+ }
+
+ // mix the sample, overlap
+ switch(bsi->acmod) {
+ case 7: // 3/2
+ left = samples[0];
+ center = samples[1];
+ right = samples[2];
+ left_sur = samples[3];
+ right_sur = samples[4];
+ delay_left = delay[0];
+ delay_right = delay[1];
+ delay1_left = delay1[0];
+ delay1_center = delay1[1];
+ delay1_right = delay1[2];
+ delay1_sl = delay1[3];
+ delay1_sr = delay1[4];
+
+ for (i = 0; i < 256; i++) {
+ left_tmp = dm_par->unit * *left++ + dm_par->clev * *center + dm_par->slev * *left_sur++;
+ right_tmp= dm_par->unit * *right++ + dm_par->clev * *center++ + dm_par->slev * *right_sur++;
+ *s16_samples++ = (int16_t)(left_tmp + *delay_left);
+ *s16_samples++ = (int16_t)(right_tmp + *delay_right);
+ *delay_left++ = dm_par->unit * *delay1_left++ + dm_par->clev * *delay1_center + dm_par->slev * *delay1_sl++;
+ *delay_right++ = dm_par->unit * *delay1_right++ + dm_par->clev * *center++ + dm_par->slev * *delay1_sr++;
+ }
+ break;
+ case 6: // 2/2
+ left = samples[0];
+ right = samples[1];
+ left_sur = samples[2];
+ right_sur = samples[3];
+ delay_left = delay[0];
+ delay_right = delay[1];
+ delay1_left = delay1[0];
+ delay1_right = delay1[1];
+ delay1_sl = delay1[2];
+ delay1_sr = delay1[3];
+
+ for (i = 0; i < 256; i++) {
+ left_tmp = dm_par->unit * *left++ + dm_par->slev * *left_sur++;
+ right_tmp= dm_par->unit * *right++ + dm_par->slev * *right_sur++;
+ *s16_samples++ = (int16_t)(left_tmp + *delay_left);
+ *s16_samples++ = (int16_t)(right_tmp + *delay_right);
+ *delay_left++ = dm_par->unit * *delay1_left++ + dm_par->slev * *delay1_sl++;
+ *delay_right++ = dm_par->unit * *delay1_right++ + dm_par->slev * *delay1_sr++;
+ }
+ break;
+ case 5: // 3/1
+ left = samples[0];
+ center = samples[1];
+ right = samples[2];
+ right_sur = samples[3];
+ delay_left = delay[0];
+ delay_right = delay[1];
+ delay1_left = delay1[0];
+ delay1_center = delay1[1];
+ delay1_right = delay1[2];
+ delay1_sl = delay1[3];
+
+ for (i = 0; i < 256; i++) {
+ left_tmp = dm_par->unit * *left++ + dm_par->clev * *center - dm_par->slev * *right_sur;
+ right_tmp= dm_par->unit * *right++ + dm_par->clev * *center++ + dm_par->slev * *right_sur++;
+ *s16_samples++ = (int16_t)(left_tmp + *delay_left);
+ *s16_samples++ = (int16_t)(right_tmp + *delay_right);
+ *delay_left++ = dm_par->unit * *delay1_left++ + dm_par->clev * *delay1_center + dm_par->slev * *delay1_sl;
+ *delay_right++ = dm_par->unit * *delay1_right++ + dm_par->clev * *center++ + dm_par->slev * *delay1_sl++;
+ }
+ break;
+ case 4: // 2/1
+ left = samples[0];
+ right = samples[1];
+ right_sur = samples[2];
+ delay_left = delay[0];
+ delay_right = delay[1];
+ delay1_left = delay1[0];
+ delay1_right = delay1[1];
+ delay1_sl = delay1[2];
+
+ for (i = 0; i < 256; i++) {
+ left_tmp = dm_par->unit * *left++ - dm_par->slev * *right_sur;
+ right_tmp= dm_par->unit * *right++ + dm_par->slev * *right_sur++;
+ *s16_samples++ = (int16_t)(left_tmp + *delay_left);
+ *s16_samples++ = (int16_t)(right_tmp + *delay_right);
+ *delay_left++ = dm_par->unit * *delay1_left++ + dm_par->slev * *delay1_sl;
+ *delay_right++ = dm_par->unit * *delay1_right++ + dm_par->slev * *delay1_sl++;
+ }
+ break;
+ case 3: // 3/0
+ left = samples[0];
+ center = samples[1];
+ right = samples[2];
+ delay_left = delay[0];
+ delay_right = delay[1];
+ delay1_left = delay1[0];
+ delay1_center = delay1[1];
+ delay1_right = delay1[2];
+
+ for (i = 0; i < 256; i++) {
+ left_tmp = dm_par->unit * *left++ + dm_par->clev * *center;
+ right_tmp= dm_par->unit * *right++ + dm_par->clev * *center++;
+ *s16_samples++ = (int16_t)(left_tmp + *delay_left);
+ *s16_samples++ = (int16_t)(right_tmp + *delay_right);
+ *delay_left++ = dm_par->unit * *delay1_left++ + dm_par->clev * *delay1_center;
+ *delay_right++ = dm_par->unit * *delay1_right++ + dm_par->clev * *center++;
+ }
+ break;
+ case 2: // copy to output
+ for (i = 0; i < 256; i++) {
+ *s16_samples++ = (int16_t)samples[0][i];
+ *s16_samples++ = (int16_t)samples[1][i];
+ }
+ break;
+ }
+ }
+}
+