--- /dev/null
+/*
+ * imdct.c
+ * Copyright (C) 2000-2002 Michel Lespinasse <walken@zoy.org>
+ * Copyright (C) 1999-2000 Aaron Holtzman <aholtzma@ess.engr.uvic.ca>
+ *
+ * The ifft algorithms in this file have been largely inspired by Dan
+ * Bernstein's work, djbfft, available at http://cr.yp.to/djbfft.html
+ *
+ * This file is part of a52dec, a free ATSC A-52 stream decoder.
+ * See http://liba52.sourceforge.net/ for updates.
+ *
+ * a52dec 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.
+ *
+ * a52dec 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
+ */
+
+#include "config.h"
+
+#include <math.h>
+#include <stdio.h>
+#ifdef LIBA52_DJBFFT
+#include <fftc4.h>
+#endif
+#ifndef M_PI
+#define M_PI 3.1415926535897932384626433832795029
+#endif
+#include <inttypes.h>
+
+#include "a52.h"
+#include "a52_internal.h"
+#include "mm_accel.h"
+
+typedef struct complex_s {
+ sample_t real;
+ sample_t imag;
+} complex_t;
+
+static complex_t buf[128];
+
+static uint8_t fftorder[] = {
+ 0,128, 64,192, 32,160,224, 96, 16,144, 80,208,240,112, 48,176,
+ 8,136, 72,200, 40,168,232,104,248,120, 56,184, 24,152,216, 88,
+ 4,132, 68,196, 36,164,228,100, 20,148, 84,212,244,116, 52,180,
+ 252,124, 60,188, 28,156,220, 92, 12,140, 76,204,236,108, 44,172,
+ 2,130, 66,194, 34,162,226, 98, 18,146, 82,210,242,114, 50,178,
+ 10,138, 74,202, 42,170,234,106,250,122, 58,186, 26,154,218, 90,
+ 254,126, 62,190, 30,158,222, 94, 14,142, 78,206,238,110, 46,174,
+ 6,134, 70,198, 38,166,230,102,246,118, 54,182, 22,150,214, 86
+};
+
+/* Root values for IFFT */
+static sample_t roots16[3];
+static sample_t roots32[7];
+static sample_t roots64[15];
+static sample_t roots128[31];
+
+/* Twiddle factors for IMDCT */
+static complex_t pre1[128];
+static complex_t post1[64];
+static complex_t pre2[64];
+static complex_t post2[32];
+
+/* Windowing function for Modified DCT - Thank you acroread */
+static const sample_t a52_imdct_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 void (* ifft128) (complex_t * buf);
+static void (* ifft64) (complex_t * buf);
+
+static inline void ifft2 (complex_t * buf)
+{
+ double r, i;
+
+ r = buf[0].real;
+ i = buf[0].imag;
+ buf[0].real += buf[1].real;
+ buf[0].imag += buf[1].imag;
+ buf[1].real = r - buf[1].real;
+ buf[1].imag = i - buf[1].imag;
+}
+
+static inline void ifft4 (complex_t * buf)
+{
+ double tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7, tmp8;
+
+ tmp1 = buf[0].real + buf[1].real;
+ tmp2 = buf[3].real + buf[2].real;
+ tmp3 = buf[0].imag + buf[1].imag;
+ tmp4 = buf[2].imag + buf[3].imag;
+ tmp5 = buf[0].real - buf[1].real;
+ tmp6 = buf[0].imag - buf[1].imag;
+ tmp7 = buf[2].imag - buf[3].imag;
+ tmp8 = buf[3].real - buf[2].real;
+
+ buf[0].real = tmp1 + tmp2;
+ buf[0].imag = tmp3 + tmp4;
+ buf[2].real = tmp1 - tmp2;
+ buf[2].imag = tmp3 - tmp4;
+ buf[1].real = tmp5 + tmp7;
+ buf[1].imag = tmp6 + tmp8;
+ buf[3].real = tmp5 - tmp7;
+ buf[3].imag = tmp6 - tmp8;
+}
+
+/* the basic split-radix ifft butterfly */
+
+#define BUTTERFLY(a0,a1,a2,a3,wr,wi) do { \
+ tmp5 = a2.real * wr + a2.imag * wi; \
+ tmp6 = a2.imag * wr - a2.real * wi; \
+ tmp7 = a3.real * wr - a3.imag * wi; \
+ tmp8 = a3.imag * wr + a3.real * wi; \
+ tmp1 = tmp5 + tmp7; \
+ tmp2 = tmp6 + tmp8; \
+ tmp3 = tmp6 - tmp8; \
+ tmp4 = tmp7 - tmp5; \
+ a2.real = a0.real - tmp1; \
+ a2.imag = a0.imag - tmp2; \
+ a3.real = a1.real - tmp3; \
+ a3.imag = a1.imag - tmp4; \
+ a0.real += tmp1; \
+ a0.imag += tmp2; \
+ a1.real += tmp3; \
+ a1.imag += tmp4; \
+} while (0)
+
+/* split-radix ifft butterfly, specialized for wr=1 wi=0 */
+
+#define BUTTERFLY_ZERO(a0,a1,a2,a3) do { \
+ tmp1 = a2.real + a3.real; \
+ tmp2 = a2.imag + a3.imag; \
+ tmp3 = a2.imag - a3.imag; \
+ tmp4 = a3.real - a2.real; \
+ a2.real = a0.real - tmp1; \
+ a2.imag = a0.imag - tmp2; \
+ a3.real = a1.real - tmp3; \
+ a3.imag = a1.imag - tmp4; \
+ a0.real += tmp1; \
+ a0.imag += tmp2; \
+ a1.real += tmp3; \
+ a1.imag += tmp4; \
+} while (0)
+
+/* split-radix ifft butterfly, specialized for wr=wi */
+
+#define BUTTERFLY_HALF(a0,a1,a2,a3,w) do { \
+ tmp5 = (a2.real + a2.imag) * w; \
+ tmp6 = (a2.imag - a2.real) * w; \
+ tmp7 = (a3.real - a3.imag) * w; \
+ tmp8 = (a3.imag + a3.real) * w; \
+ tmp1 = tmp5 + tmp7; \
+ tmp2 = tmp6 + tmp8; \
+ tmp3 = tmp6 - tmp8; \
+ tmp4 = tmp7 - tmp5; \
+ a2.real = a0.real - tmp1; \
+ a2.imag = a0.imag - tmp2; \
+ a3.real = a1.real - tmp3; \
+ a3.imag = a1.imag - tmp4; \
+ a0.real += tmp1; \
+ a0.imag += tmp2; \
+ a1.real += tmp3; \
+ a1.imag += tmp4; \
+} while (0)
+
+static inline void ifft8 (complex_t * buf)
+{
+ double tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7, tmp8;
+
+ ifft4 (buf);
+ ifft2 (buf + 4);
+ ifft2 (buf + 6);
+ BUTTERFLY_ZERO (buf[0], buf[2], buf[4], buf[6]);
+ BUTTERFLY_HALF (buf[1], buf[3], buf[5], buf[7], roots16[1]);
+}
+
+static void ifft_pass (complex_t * buf, sample_t * weight, int n)
+{
+ complex_t * buf1;
+ complex_t * buf2;
+ complex_t * buf3;
+ double tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7, tmp8;
+ int i;
+
+ buf++;
+ buf1 = buf + n;
+ buf2 = buf + 2 * n;
+ buf3 = buf + 3 * n;
+
+ BUTTERFLY_ZERO (buf[-1], buf1[-1], buf2[-1], buf3[-1]);
+
+ i = n - 1;
+
+ do {
+ BUTTERFLY (buf[0], buf1[0], buf2[0], buf3[0], weight[n], weight[2*i]);
+ buf++;
+ buf1++;
+ buf2++;
+ buf3++;
+ weight++;
+ } while (--i);
+}
+
+static void ifft16 (complex_t * buf)
+{
+ ifft8 (buf);
+ ifft4 (buf + 8);
+ ifft4 (buf + 12);
+ ifft_pass (buf, roots16 - 4, 4);
+}
+
+static void ifft32 (complex_t * buf)
+{
+ ifft16 (buf);
+ ifft8 (buf + 16);
+ ifft8 (buf + 24);
+ ifft_pass (buf, roots32 - 8, 8);
+}
+
+static void ifft64_c (complex_t * buf)
+{
+ ifft32 (buf);
+ ifft16 (buf + 32);
+ ifft16 (buf + 48);
+ ifft_pass (buf, roots64 - 16, 16);
+}
+
+static void ifft128_c (complex_t * buf)
+{
+ ifft32 (buf);
+ ifft16 (buf + 32);
+ ifft16 (buf + 48);
+ ifft_pass (buf, roots64 - 16, 16);
+
+ ifft32 (buf + 64);
+ ifft32 (buf + 96);
+ ifft_pass (buf, roots128 - 32, 32);
+}
+
+void a52_imdct_512 (sample_t * data, sample_t * delay, sample_t bias)
+{
+ int i, k;
+ sample_t t_r, t_i, a_r, a_i, b_r, b_i, w_1, w_2;
+ const sample_t * window = a52_imdct_window;
+
+ for (i = 0; i < 128; i++) {
+ k = fftorder[i];
+ t_r = pre1[i].real;
+ t_i = pre1[i].imag;
+
+ buf[i].real = t_i * data[255-k] + t_r * data[k];
+ buf[i].imag = t_r * data[255-k] - t_i * data[k];
+ }
+
+ ifft128 (buf);
+
+ /* Post IFFT complex multiply plus IFFT complex conjugate*/
+ /* Window and convert to real valued signal */
+ for (i = 0; i < 64; i++) {
+ /* y[n] = z[n] * (xcos1[n] + j * xsin1[n]) ; */
+ t_r = post1[i].real;
+ t_i = post1[i].imag;
+
+ a_r = t_r * buf[i].real + t_i * buf[i].imag;
+ a_i = t_i * buf[i].real - t_r * buf[i].imag;
+ b_r = t_i * buf[127-i].real + t_r * buf[127-i].imag;
+ b_i = t_r * buf[127-i].real - t_i * buf[127-i].imag;
+
+ w_1 = window[2*i];
+ w_2 = window[255-2*i];
+ data[2*i] = delay[2*i] * w_2 - a_r * w_1 + bias;
+ data[255-2*i] = delay[2*i] * w_1 + a_r * w_2 + bias;
+ delay[2*i] = a_i;
+
+ w_1 = window[2*i+1];
+ w_2 = window[254-2*i];
+ data[2*i+1] = delay[2*i+1] * w_2 + b_r * w_1 + bias;
+ data[254-2*i] = delay[2*i+1] * w_1 - b_r * w_2 + bias;
+ delay[2*i+1] = b_i;
+ }
+}
+
+void a52_imdct_256(sample_t data[],sample_t delay[],sample_t bias)
+{
+ int i, k;
+ sample_t t_r, t_i, a_r, a_i, b_r, b_i, c_r, c_i, d_r, d_i, w_1, w_2;
+ complex_t * buf1, * buf2;
+ const sample_t * window = a52_imdct_window;
+
+ buf1 = &buf[0];
+ buf2 = &buf[64];
+
+ /* Pre IFFT complex multiply plus IFFT cmplx conjugate */
+ for (i = 0; i < 64; i++) {
+ k = fftorder[i];
+ t_r = pre2[i].real;
+ t_i = pre2[i].imag;
+
+ buf1[i].real = t_i * data[254-k] + t_r * data[k];
+ buf1[i].imag = t_r * data[254-k] - t_i * data[k];
+
+ buf2[i].real = t_i * data[255-k] + t_r * data[k+1];
+ buf2[i].imag = t_r * data[255-k] - t_i * data[k+1];
+ }
+
+ ifft64 (buf1);
+ ifft64 (buf2);
+
+ /* Post IFFT complex multiply */
+ /* Window and convert to real valued signal */
+ for (i = 0; i < 32; i++) {
+ /* y1[n] = z1[n] * (xcos2[n] + j * xs in2[n]) ; */
+ t_r = post2[i].real;
+ t_i = post2[i].imag;
+
+ a_r = t_r * buf1[i].real + t_i * buf1[i].imag;
+ a_i = t_i * buf1[i].real - t_r * buf1[i].imag;
+ b_r = t_i * buf1[63-i].real + t_r * buf1[63-i].imag;
+ b_i = t_r * buf1[63-i].real - t_i * buf1[63-i].imag;
+
+ c_r = t_r * buf2[i].real + t_i * buf2[i].imag;
+ c_i = t_i * buf2[i].real - t_r * buf2[i].imag;
+ d_r = t_i * buf2[63-i].real + t_r * buf2[63-i].imag;
+ d_i = t_r * buf2[63-i].real - t_i * buf2[63-i].imag;
+
+ w_1 = window[2*i];
+ w_2 = window[255-2*i];
+ data[2*i] = delay[2*i] * w_2 - a_r * w_1 + bias;
+ data[255-2*i] = delay[2*i] * w_1 + a_r * w_2 + bias;
+ delay[2*i] = c_i;
+
+ w_1 = window[128+2*i];
+ w_2 = window[127-2*i];
+ data[128+2*i] = delay[127-2*i] * w_2 + a_i * w_1 + bias;
+ data[127-2*i] = delay[127-2*i] * w_1 - a_i * w_2 + bias;
+ delay[127-2*i] = c_r;
+
+ w_1 = window[2*i+1];
+ w_2 = window[254-2*i];
+ data[2*i+1] = delay[2*i+1] * w_2 - b_i * w_1 + bias;
+ data[254-2*i] = delay[2*i+1] * w_1 + b_i * w_2 + bias;
+ delay[2*i+1] = d_r;
+
+ w_1 = window[129+2*i];
+ w_2 = window[126-2*i];
+ data[129+2*i] = delay[126-2*i] * w_2 + b_r * w_1 + bias;
+ data[126-2*i] = delay[126-2*i] * w_1 - b_r * w_2 + bias;
+ delay[126-2*i] = d_i;
+ }
+}
+
+void a52_imdct_init (uint32_t mm_accel)
+{
+ int i, k;
+
+ for (i = 0; i < 3; i++)
+ roots16[i] = cos ((M_PI / 8) * (i + 1));
+
+ for (i = 0; i < 7; i++)
+ roots32[i] = cos ((M_PI / 16) * (i + 1));
+
+ for (i = 0; i < 15; i++)
+ roots64[i] = cos ((M_PI / 32) * (i + 1));
+
+ for (i = 0; i < 31; i++)
+ roots128[i] = cos ((M_PI / 64) * (i + 1));
+
+ for (i = 0; i < 64; i++) {
+ k = fftorder[i] / 2 + 64;
+ pre1[i].real = cos ((M_PI / 256) * (k - 0.25));
+ pre1[i].imag = sin ((M_PI / 256) * (k - 0.25));
+ }
+
+ for (i = 64; i < 128; i++) {
+ k = fftorder[i] / 2 + 64;
+ pre1[i].real = -cos ((M_PI / 256) * (k - 0.25));
+ pre1[i].imag = -sin ((M_PI / 256) * (k - 0.25));
+ }
+
+ for (i = 0; i < 64; i++) {
+ post1[i].real = cos ((M_PI / 256) * (i + 0.5));
+ post1[i].imag = sin ((M_PI / 256) * (i + 0.5));
+ }
+
+ for (i = 0; i < 64; i++) {
+ k = fftorder[i] / 4;
+ pre2[i].real = cos ((M_PI / 128) * (k - 0.25));
+ pre2[i].imag = sin ((M_PI / 128) * (k - 0.25));
+ }
+
+ for (i = 0; i < 32; i++) {
+ post2[i].real = cos ((M_PI / 128) * (i + 0.5));
+ post2[i].imag = sin ((M_PI / 128) * (i + 0.5));
+ }
+
+#ifdef LIBA52_DJBFFT
+ if (mm_accel & MM_ACCEL_DJBFFT) {
+ fprintf (stderr, "Using djbfft for IMDCT transform\n");
+ ifft128 = (void (*) (complex_t *)) fftc4_un128;
+ ifft64 = (void (*) (complex_t *)) fftc4_un64;
+ } else
+#endif
+ {
+// fprintf (stderr, "No accelerated IMDCT transform found\n");
+ ifft128 = ifft128_c;
+ ifft64 = ifft64_c;
+ }
+}
projects / goodguy / history.git / blobdiff