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Diffstat (limited to 'liba52/imdct.c')
| -rw-r--r-- | liba52/imdct.c | 411 |
1 files changed, 411 insertions, 0 deletions
diff --git a/liba52/imdct.c b/liba52/imdct.c new file mode 100644 index 0000000000..8ef4b9d50e --- /dev/null +++ b/liba52/imdct.c @@ -0,0 +1,411 @@ +/* + * imdct.c + * Copyright (C) 2000-2001 Michel Lespinasse <walken@zoy.org> + * Copyright (C) 1999-2000 Aaron Holtzman <aholtzma@ess.engr.uvic.ca> + * + * 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> +#ifndef M_PI +#define M_PI 3.1415926535897932384626433832795029 +#endif +#include <inttypes.h> + +#include "a52.h" +#include "a52_internal.h" +#include "mm_accel.h" + +void (* imdct_256) (sample_t data[], sample_t delay[], sample_t bias); +void (* imdct_512) (sample_t data[], sample_t delay[], sample_t bias); + +typedef struct complex_s { + sample_t real; + sample_t imag; +} complex_t; + + +/* 128 point bit-reverse LUT */ +static uint8_t bit_reverse_512[] = { + 0x00, 0x40, 0x20, 0x60, 0x10, 0x50, 0x30, 0x70, + 0x08, 0x48, 0x28, 0x68, 0x18, 0x58, 0x38, 0x78, + 0x04, 0x44, 0x24, 0x64, 0x14, 0x54, 0x34, 0x74, + 0x0c, 0x4c, 0x2c, 0x6c, 0x1c, 0x5c, 0x3c, 0x7c, + 0x02, 0x42, 0x22, 0x62, 0x12, 0x52, 0x32, 0x72, + 0x0a, 0x4a, 0x2a, 0x6a, 0x1a, 0x5a, 0x3a, 0x7a, + 0x06, 0x46, 0x26, 0x66, 0x16, 0x56, 0x36, 0x76, + 0x0e, 0x4e, 0x2e, 0x6e, 0x1e, 0x5e, 0x3e, 0x7e, + 0x01, 0x41, 0x21, 0x61, 0x11, 0x51, 0x31, 0x71, + 0x09, 0x49, 0x29, 0x69, 0x19, 0x59, 0x39, 0x79, + 0x05, 0x45, 0x25, 0x65, 0x15, 0x55, 0x35, 0x75, + 0x0d, 0x4d, 0x2d, 0x6d, 0x1d, 0x5d, 0x3d, 0x7d, + 0x03, 0x43, 0x23, 0x63, 0x13, 0x53, 0x33, 0x73, + 0x0b, 0x4b, 0x2b, 0x6b, 0x1b, 0x5b, 0x3b, 0x7b, + 0x07, 0x47, 0x27, 0x67, 0x17, 0x57, 0x37, 0x77, + 0x0f, 0x4f, 0x2f, 0x6f, 0x1f, 0x5f, 0x3f, 0x7f}; + +static uint8_t bit_reverse_256[] = { + 0x00, 0x20, 0x10, 0x30, 0x08, 0x28, 0x18, 0x38, + 0x04, 0x24, 0x14, 0x34, 0x0c, 0x2c, 0x1c, 0x3c, + 0x02, 0x22, 0x12, 0x32, 0x0a, 0x2a, 0x1a, 0x3a, + 0x06, 0x26, 0x16, 0x36, 0x0e, 0x2e, 0x1e, 0x3e, + 0x01, 0x21, 0x11, 0x31, 0x09, 0x29, 0x19, 0x39, + 0x05, 0x25, 0x15, 0x35, 0x0d, 0x2d, 0x1d, 0x3d, + 0x03, 0x23, 0x13, 0x33, 0x0b, 0x2b, 0x1b, 0x3b, + 0x07, 0x27, 0x17, 0x37, 0x0f, 0x2f, 0x1f, 0x3f}; + +static complex_t buf[128]; + +/* Twiddle factor LUT */ +static complex_t w_1[1]; +static complex_t w_2[2]; +static complex_t w_4[4]; +static complex_t w_8[8]; +static complex_t w_16[16]; +static complex_t w_32[32]; +static complex_t w_64[64]; +static complex_t * w[7] = {w_1, w_2, w_4, w_8, w_16, w_32, w_64}; + +/* Twiddle factors for IMDCT */ +static sample_t xcos1[128]; +static sample_t xsin1[128]; +static sample_t xcos2[64]; +static sample_t xsin2[64]; + +/* Windowing function for Modified DCT - Thank you acroread */ +sample_t 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 inline void swap_cmplx(complex_t *a, complex_t *b) +{ + complex_t tmp; + + tmp = *a; + *a = *b; + *b = tmp; +} + + + +static inline complex_t cmplx_mult(complex_t a, complex_t b) +{ + complex_t ret; + + ret.real = a.real * b.real - a.imag * b.imag; + ret.imag = a.real * b.imag + a.imag * b.real; + + return ret; +} + +void +imdct_do_512(sample_t data[],sample_t delay[], sample_t bias) +{ + int i,k; + int p,q; + int m; + int two_m; + int two_m_plus_one; + + sample_t tmp_a_i; + sample_t tmp_a_r; + sample_t tmp_b_i; + sample_t tmp_b_r; + + sample_t *data_ptr; + sample_t *delay_ptr; + sample_t *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]) ; */ + buf[i].real = (data[256-2*i-1] * xcos1[i]) - (data[2*i] * xsin1[i]); + buf[i].imag = -1.0 * ((data[2*i] * xcos1[i]) + (data[256-2*i-1] * xsin1[i])); + } + + /* Bit reversed shuffling */ + for(i=0; i<128; i++) { + k = bit_reverse_512[i]; + if (k < i) + swap_cmplx(&buf[i],&buf[k]); + } + + /* FFT Merge */ + for (m=0; m < 7; m++) { + if(m) + two_m = (1 << m); + else + two_m = 1; + + two_m_plus_one = (1 << (m+1)); + + for(k = 0; k < two_m; k++) { + for(i = 0; i < 128; i += two_m_plus_one) { + p = k + i; + q = p + two_m; + tmp_a_r = buf[p].real; + tmp_a_i = buf[p].imag; + tmp_b_r = buf[q].real * w[m][k].real - buf[q].imag * w[m][k].imag; + tmp_b_i = buf[q].imag * w[m][k].real + buf[q].real * w[m][k].imag; + buf[p].real = tmp_a_r + tmp_b_r; + buf[p].imag = tmp_a_i + tmp_b_i; + buf[q].real = tmp_a_r - tmp_b_r; + buf[q].imag = tmp_a_i - tmp_b_i; + } + } + } + + /* Post IFFT complex multiply plus IFFT complex conjugate*/ + for( i=0; i < 128; i++) { + /* y[n] = z[n] * (xcos1[n] + j * xsin1[n]) ; */ + tmp_a_r = buf[i].real; + tmp_a_i = -1.0 * buf[i].imag; + buf[i].real =(tmp_a_r * xcos1[i]) - (tmp_a_i * xsin1[i]); + buf[i].imag =(tmp_a_r * xsin1[i]) + (tmp_a_i * xcos1[i]); + } + + data_ptr = data; + delay_ptr = delay; + window_ptr = imdct_window; + + /* Window and convert to real valued signal */ + for(i=0; i< 64; i++) { + *data_ptr++ = -buf[64+i].imag * *window_ptr++ + *delay_ptr++ + bias; + *data_ptr++ = buf[64-i-1].real * *window_ptr++ + *delay_ptr++ + bias; + } + + for(i=0; i< 64; i++) { + *data_ptr++ = -buf[i].real * *window_ptr++ + *delay_ptr++ + bias; + *data_ptr++ = buf[128-i-1].imag * *window_ptr++ + *delay_ptr++ + bias; + } + + /* 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].real * *--window_ptr; + *delay_ptr++ = buf[64-i-1].imag * *--window_ptr; + } + + for(i=0; i<64; i++) { + *delay_ptr++ = buf[i].imag * *--window_ptr; + *delay_ptr++ = -buf[128-i-1].real * *--window_ptr; + } +} + +void +imdct_do_256(sample_t data[],sample_t delay[],sample_t bias) +{ + int i,k; + int p,q; + int m; + int two_m; + int two_m_plus_one; + + sample_t tmp_a_i; + sample_t tmp_a_r; + sample_t tmp_b_i; + sample_t tmp_b_r; + + sample_t *data_ptr; + sample_t *delay_ptr; + sample_t *window_ptr; + + complex_t *buf_1, *buf_2; + + buf_1 = &buf[0]; + buf_2 = &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] */ + + p = 2 * (128-2*k-1); + q = 2 * (2 * k); + + /* Z1[k] = (X1[128-2*k-1] + j * X1[2*k]) * (xcos2[k] + j * xsin2[k]); */ + buf_1[k].real = data[p] * xcos2[k] - data[q] * xsin2[k]; + buf_1[k].imag = -1.0f * (data[q] * xcos2[k] + data[p] * xsin2[k]); + /* Z2[k] = (X2[128-2*k-1] + j * X2[2*k]) * (xcos2[k] + j * xsin2[k]); */ + buf_2[k].real = data[p + 1] * xcos2[k] - data[q + 1] * xsin2[k]; + buf_2[k].imag = -1.0f * ( data[q + 1] * xcos2[k] + data[p + 1] * xsin2[k]); + } + + /* IFFT Bit reversed shuffling */ + for(i=0; i<64; i++) { + k = bit_reverse_256[i]; + if (k < i) { + swap_cmplx(&buf_1[i],&buf_1[k]); + swap_cmplx(&buf_2[i],&buf_2[k]); + } + } + + /* FFT Merge */ + for (m=0; m < 6; m++) { + two_m = (1 << m); + two_m_plus_one = (1 << (m+1)); + + /* FIXME */ + if(m) + two_m = (1 << m); + else + two_m = 1; + + for(k = 0; k < two_m; k++) { + for(i = 0; i < 64; i += two_m_plus_one) { + p = k + i; + q = p + two_m; + /* Do block 1 */ + tmp_a_r = buf_1[p].real; + tmp_a_i = buf_1[p].imag; + tmp_b_r = buf_1[q].real * w[m][k].real - buf_1[q].imag * w[m][k].imag; + tmp_b_i = buf_1[q].imag * w[m][k].real + buf_1[q].real * w[m][k].imag; + buf_1[p].real = tmp_a_r + tmp_b_r; + buf_1[p].imag = tmp_a_i + tmp_b_i; + buf_1[q].real = tmp_a_r - tmp_b_r; + buf_1[q].imag = tmp_a_i - tmp_b_i; + + /* Do block 2 */ + tmp_a_r = buf_2[p].real; + tmp_a_i = buf_2[p].imag; + tmp_b_r = buf_2[q].real * w[m][k].real - buf_2[q].imag * w[m][k].imag; + tmp_b_i = buf_2[q].imag * w[m][k].real + buf_2[q].real * w[m][k].imag; + buf_2[p].real = tmp_a_r + tmp_b_r; + buf_2[p].imag = tmp_a_i + tmp_b_i; + buf_2[q].real = tmp_a_r - tmp_b_r; + buf_2[q].imag = tmp_a_i - tmp_b_i; + } + } + } + + /* Post IFFT complex multiply */ + for( i=0; i < 64; i++) { + /* y1[n] = z1[n] * (xcos2[n] + j * xs in2[n]) ; */ + tmp_a_r = buf_1[i].real; + tmp_a_i = -buf_1[i].imag; + buf_1[i].real =(tmp_a_r * xcos2[i]) - (tmp_a_i * xsin2[i]); + buf_1[i].imag =(tmp_a_r * xsin2[i]) + (tmp_a_i * xcos2[i]); + /* y2[n] = z2[n] * (xcos2[n] + j * xsin2[n]) ; */ + tmp_a_r = buf_2[i].real; + tmp_a_i = -buf_2[i].imag; + buf_2[i].real =(tmp_a_r * xcos2[i]) - (tmp_a_i * xsin2[i]); + buf_2[i].imag =(tmp_a_r * xsin2[i]) + (tmp_a_i * xcos2[i]); + } + + data_ptr = data; + delay_ptr = delay; + window_ptr = imdct_window; + + /* Window and convert to real valued signal */ + for(i=0; i< 64; i++) { + *data_ptr++ = -buf_1[i].imag * *window_ptr++ + *delay_ptr++ + bias; + *data_ptr++ = buf_1[64-i-1].real * *window_ptr++ + *delay_ptr++ + bias; + } + + for(i=0; i< 64; i++) { + *data_ptr++ = -buf_1[i].real * *window_ptr++ + *delay_ptr++ + bias; + *data_ptr++ = buf_1[64-i-1].imag * *window_ptr++ + *delay_ptr++ + bias; + } + + delay_ptr = delay; + + for(i=0; i< 64; i++) { + *delay_ptr++ = -buf_2[i].real * *--window_ptr; + *delay_ptr++ = buf_2[64-i-1].imag * *--window_ptr; + } + + for(i=0; i< 64; i++) { + *delay_ptr++ = buf_2[i].imag * *--window_ptr; + *delay_ptr++ = -buf_2[64-i-1].real * *--window_ptr; + } +} + +void imdct_init (uint32_t mm_accel) +{ +#ifdef LIBA52_MLIB + if (mm_accel & MM_ACCEL_MLIB) { + fprintf (stderr, "Using mlib for IMDCT transform\n"); + imdct_512 = imdct_do_512_mlib; + imdct_256 = imdct_do_256_mlib; + } else +#endif + { + int i, j, k; + + fprintf (stderr, "No accelerated IMDCT transform found\n"); + + /* Twiddle factors to turn IFFT into IMDCT */ + for (i = 0; i < 128; i++) { + xcos1[i] = -cos ((M_PI / 2048) * (8 * i + 1)); + xsin1[i] = -sin ((M_PI / 2048) * (8 * i + 1)); + } + + /* More twiddle factors to turn IFFT into IMDCT */ + for (i = 0; i < 64; i++) { + xcos2[i] = -cos ((M_PI / 1024) * (8 * i + 1)); + xsin2[i] = -sin ((M_PI / 1024) * (8 * i + 1)); + } + + for (i = 0; i < 7; i++) { + j = 1 << i; + for (k = 0; k < j; k++) { + w[i][k].real = cos (-M_PI * k / j); + w[i][k].imag = sin (-M_PI * k / j); + } + } + imdct_512 = imdct_do_512; + imdct_256 = imdct_do_256; + } +} |