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-rw-r--r--ac3dec/imdct_c.c218
1 files changed, 0 insertions, 218 deletions
diff --git a/ac3dec/imdct_c.c b/ac3dec/imdct_c.c
deleted file mode 100644
index 1f2bfe84..00000000
--- a/ac3dec/imdct_c.c
+++ /dev/null
@@ -1,218 +0,0 @@
-/*
- * 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.
- *
- *
- */
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <math.h>
-#include "ac3.h"
-#include "ac3_internal.h"
-
-#include "downmix.h"
-#include "imdct_c.h"
-#include "srfft.h"
-
-
-#define N 512
-
-extern void (*imdct_do_512) (float data[],float delay[]);
-extern void (*imdct_do_512_nol) (float data[], float delay[]);
-extern void (*fft_64p) (complex_t *);
-
-extern const int pm128[];
-extern float window[];
-extern complex_t buf[128];
-
-extern void fft_64p_c (complex_t *);
-extern void fft_128p_c (complex_t *);
-
-static void imdct_do_512_c (float data[],float delay[]);
-static void imdct_do_512_nol_c (float data[], float delay[]);
-
-/* Twiddle factors for IMDCT */
-static float xcos1[128] __attribute__((aligned(16)));
-static float xsin1[128] __attribute__((aligned(16)));
-
-
-int imdct_init_c (void)
-{
- int i;
- float scale = 255.99609372;
-
- imdct_do_512 = imdct_do_512_c;
- imdct_do_512_nol = imdct_do_512_nol_c;
- fft_64p = fft_64p_c;
-
- /* 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;
- }
-
- return 0;
-}
-
-
-static void imdct_do_512_c (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_c (&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;
- }
-}
-
-
-static void imdct_do_512_nol_c (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_c (&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;
- }
-}