git.sesse.net Git - vlc/blob - src/ac3_decoder/ac3_imdct.c

   1 /*****************************************************************************
   2  * ac3_imdct.c: ac3 DCT
   3  *****************************************************************************
   4  * Copyright (C) 1999, 2000 VideoLAN
   5  * $Id: ac3_imdct.c,v 1.17 2001/04/30 21:04:20 reno Exp $
   6  *
   7  * Authors: Michel Kaempf <maxx@via.ecp.fr>
   8  *          Aaron Holtzman <aholtzma@engr.uvic.ca>
   9  *          Renaud Dartus <reno@videolan.org>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  24  *****************************************************************************/
  25
  26 #include "defs.h"
  27
  28 #include <math.h>
  29 #include <stdio.h>
  30
  31 #include "config.h"
  32 #include "common.h"
  33 #include "threads.h"
  34 #include "mtime.h"
  35
  36 #include "stream_control.h"
  37 #include "input_ext-dec.h"
  38
  39 #include "ac3_decoder.h"
  40 #include "ac3_internal.h"
  41
  42 #include "ac3_downmix.h"
  43 #include "ac3_imdct_c.h"
  44 #if 0
  45 #include "ac3_imdct_kni.h"
  46 #endif
  47
  48 #include "tests.h"
  49
  50 #ifndef M_PI
  51 #   define M_PI 3.14159265358979323846
  52 #endif
  53
  54
  55 void imdct_init(imdct_t * p_imdct)
  56 {
  57         int i;
  58         float scale = 255.99609372;
  59
  60 #if 0
  61         if ( TestCPU (CPU_CAPABILITY_MMX) )
  62     {
  63         imdct_init_kni (p_imdct);
  64     } else
  65 #endif
  66     {
  67         imdct_init_c (p_imdct);
  68     }
  69
  70         /* More twiddle factors to turn IFFT into IMDCT */
  71         for (i=0; i < 64; i++) {
  72                 p_imdct->xcos2[i] = cos(2.0f * M_PI * (8*i+1)/(4*N)) * scale;
  73                 p_imdct->xsin2[i] = sin(2.0f * M_PI * (8*i+1)/(4*N)) * scale;
  74         }
  75 }
  76
  77 void imdct (ac3dec_t * p_ac3dec, s16 * buffer)
  78 {
  79         int   i;
  80         int   doable = 0;
  81         float *center=NULL, *left, *right, *left_sur, *right_sur;
  82         float *delay_left, *delay_right;
  83         float *delay1_left, *delay1_right, *delay1_center, *delay1_sr, *delay1_sl;
  84         float right_tmp, left_tmp;
  85         void (*do_imdct)(imdct_t * p_imdct, float data[], float delay[]);
  86
  87         /* test if dm in frequency is doable */
  88         if (!(doable = p_ac3dec->audblk.blksw[0]))
  89     {
  90                 do_imdct = p_ac3dec->imdct.imdct_do_512;
  91     }
  92         else
  93     {
  94                 do_imdct = imdct_do_256; /* There is only a C function */
  95     }
  96
  97         /* downmix in the frequency domain if all the channels
  98          * use the same imdct */
  99         for (i=0; i < p_ac3dec->bsi.nfchans; i++)
 100     {
 101                 if (doable != p_ac3dec->audblk.blksw[i])
 102         {
 103                         do_imdct = NULL;
 104                         break;
 105                 }
 106         }
 107
 108     if (do_imdct)
 109     {
 110                 /* dowmix first and imdct */
 111         switch(p_ac3dec->bsi.acmod)
 112         {
 113                 case 7:         /* 3/2 */
 114                         p_ac3dec->downmix.downmix_3f_2r_to_2ch (p_ac3dec->samples[0], &p_ac3dec->dm_par);
 115                         break;
 116                 case 6:         /* 2/2 */
 117                         p_ac3dec->downmix.downmix_2f_2r_to_2ch (p_ac3dec->samples[0], &p_ac3dec->dm_par);
 118                         break;
 119                 case 5:         /* 3/1 */
 120                         p_ac3dec->downmix.downmix_3f_1r_to_2ch (p_ac3dec->samples[0], &p_ac3dec->dm_par);
 121                         break;
 122                 case 4:         /* 2/1 */
 123                         p_ac3dec->downmix.downmix_2f_1r_to_2ch (p_ac3dec->samples[0], &p_ac3dec->dm_par);
 124                         break;
 125                 case 3:         /* 3/0 */
 126                         p_ac3dec->downmix.downmix_3f_0r_to_2ch (p_ac3dec->samples[0], &p_ac3dec->dm_par);
 127                         break;
 128                 case 2:
 129                         break;
 130                 default:        /* 1/0 */
 131 //                      if (p_ac3dec->bsi.acmod == 1)
 132                                 center = p_ac3dec->samples[0];
 133 //                      else if (p_ac3dec->bsi.acmod == 0)
 134 //                  center = samples[ac3_config.dual_mono_ch_sel];
 135                 do_imdct(&p_ac3dec->imdct, center, p_ac3dec->imdct.delay[0]); /* no downmix*/
 136
 137                         p_ac3dec->downmix.stream_sample_1ch_to_s16 (buffer, center);
 138
 139                     return;
 140                 break;
 141         }
 142
 143                 do_imdct (&p_ac3dec->imdct, p_ac3dec->samples[0], p_ac3dec->imdct.delay[0]);
 144                 do_imdct (&p_ac3dec->imdct, p_ac3dec->samples[1], p_ac3dec->imdct.delay[1]);
 145                 p_ac3dec->downmix.stream_sample_2ch_to_s16(buffer, p_ac3dec->samples[0], p_ac3dec->samples[1]);
 146
 147         } else {
 148         /* imdct and then downmix
 149                  * delay and samples should be saved and mixed
 150                  * fprintf(stderr, "time domain downmix\n"); */
 151                 for (i=0; i<p_ac3dec->bsi.nfchans; i++)
 152         {
 153                         if (p_ac3dec->audblk.blksw[i])
 154                 /* There is only a C function */
 155                                 imdct_do_256_nol (&p_ac3dec->imdct, p_ac3dec->samples[i], p_ac3dec->imdct.delay1[i]);
 156                         else
 157                                 p_ac3dec->imdct.imdct_do_512_nol (&p_ac3dec->imdct, p_ac3dec->samples[i], p_ac3dec->imdct.delay1[i]);
 158                 }
 159
 160                 /* mix the sample, overlap */
 161                 switch(p_ac3dec->bsi.acmod)
 162         {
 163                 case 7:         /* 3/2 */
 164                         left = p_ac3dec->samples[0];
 165                         center = p_ac3dec->samples[1];
 166                         right = p_ac3dec->samples[2];
 167                         left_sur = p_ac3dec->samples[3];
 168                         right_sur = p_ac3dec->samples[4];
 169                         delay_left = p_ac3dec->imdct.delay[0];
 170                         delay_right = p_ac3dec->imdct.delay[1];
 171                         delay1_left = p_ac3dec->imdct.delay1[0];
 172                         delay1_center = p_ac3dec->imdct.delay1[1];
 173                         delay1_right = p_ac3dec->imdct.delay1[2];
 174                 delay1_sl = p_ac3dec->imdct.delay1[3];
 175                         delay1_sr = p_ac3dec->imdct.delay1[4];
 176
 177                         for (i = 0; i < 256; i++) {
 178                                 left_tmp = p_ac3dec->dm_par.unit * *left++  + p_ac3dec->dm_par.clev * *center  + p_ac3dec->dm_par.slev * *left_sur++;
 179                                 right_tmp= p_ac3dec->dm_par.unit * *right++ + p_ac3dec->dm_par.clev * *center++ + p_ac3dec->dm_par.slev * *right_sur++;
 180                                 *buffer++ = (s16)(left_tmp + *delay_left);
 181                                 *buffer++ = (s16)(right_tmp + *delay_right);
 182                                 *delay_left++ = p_ac3dec->dm_par.unit * *delay1_left++  + p_ac3dec->dm_par.clev * *delay1_center  + p_ac3dec->dm_par.slev * *delay1_sl++;
 183                                 *delay_right++ = p_ac3dec->dm_par.unit * *delay1_right++ + p_ac3dec->dm_par.clev * *center++ + p_ac3dec->dm_par.slev * *delay1_sr++;
 184                         }
 185                         break;
 186                 case 6:         /* 2/2 */
 187                         left = p_ac3dec->samples[0];
 188                         right = p_ac3dec->samples[1];
 189                         left_sur = p_ac3dec->samples[2];
 190                         right_sur = p_ac3dec->samples[3];
 191                         delay_left = p_ac3dec->imdct.delay[0];
 192                         delay_right = p_ac3dec->imdct.delay[1];
 193                         delay1_left = p_ac3dec->imdct.delay1[0];
 194                         delay1_right = p_ac3dec->imdct.delay1[1];
 195                         delay1_sl = p_ac3dec->imdct.delay1[2];
 196                         delay1_sr = p_ac3dec->imdct.delay1[3];
 197
 198                         for (i = 0; i < 256; i++) {
 199                                 left_tmp = p_ac3dec->dm_par.unit * *left++  + p_ac3dec->dm_par.slev * *left_sur++;
 200                                 right_tmp= p_ac3dec->dm_par.unit * *right++ + p_ac3dec->dm_par.slev * *right_sur++;
 201                                 *buffer++ = (s16)(left_tmp + *delay_left);
 202                                 *buffer++ = (s16)(right_tmp + *delay_right);
 203                                 *delay_left++ = p_ac3dec->dm_par.unit * *delay1_left++  + p_ac3dec->dm_par.slev * *delay1_sl++;
 204                                 *delay_right++ = p_ac3dec->dm_par.unit * *delay1_right++ + p_ac3dec->dm_par.slev * *delay1_sr++;
 205                         }
 206                         break;
 207                 case 5:         /* 3/1 */
 208                         left = p_ac3dec->samples[0];
 209                         center = p_ac3dec->samples[1];
 210                         right = p_ac3dec->samples[2];
 211                         right_sur = p_ac3dec->samples[3];
 212                         delay_left = p_ac3dec->imdct.delay[0];
 213                         delay_right = p_ac3dec->imdct.delay[1];
 214                         delay1_left = p_ac3dec->imdct.delay1[0];
 215                         delay1_center = p_ac3dec->imdct.delay1[1];
 216                         delay1_right = p_ac3dec->imdct.delay1[2];
 217                         delay1_sl = p_ac3dec->imdct.delay1[3];
 218
 219                         for (i = 0; i < 256; i++) {
 220                                 left_tmp = p_ac3dec->dm_par.unit * *left++  + p_ac3dec->dm_par.clev * *center  - p_ac3dec->dm_par.slev * *right_sur;
 221                                 right_tmp= p_ac3dec->dm_par.unit * *right++ + p_ac3dec->dm_par.clev * *center++ + p_ac3dec->dm_par.slev * *right_sur++;
 222                                 *buffer++ = (s16)(left_tmp + *delay_left);
 223                                 *buffer++ = (s16)(right_tmp + *delay_right);
 224                                 *delay_left++ = p_ac3dec->dm_par.unit * *delay1_left++  + p_ac3dec->dm_par.clev * *delay1_center  + p_ac3dec->dm_par.slev * *delay1_sl;
 225                                 *delay_right++ = p_ac3dec->dm_par.unit * *delay1_right++ + p_ac3dec->dm_par.clev * *center++ + p_ac3dec->dm_par.slev * *delay1_sl++;
 226                         }
 227                         break;
 228                 case 4:         /* 2/1 */
 229                         left = p_ac3dec->samples[0];
 230                         right = p_ac3dec->samples[1];
 231                         right_sur = p_ac3dec->samples[2];
 232                         delay_left = p_ac3dec->imdct.delay[0];
 233                         delay_right = p_ac3dec->imdct.delay[1];
 234                         delay1_left = p_ac3dec->imdct.delay1[0];
 235                         delay1_right = p_ac3dec->imdct.delay1[1];
 236                         delay1_sl = p_ac3dec->imdct.delay1[2];
 237
 238                         for (i = 0; i < 256; i++) {
 239                                 left_tmp = p_ac3dec->dm_par.unit * *left++ - p_ac3dec->dm_par.slev * *right_sur;
 240                                 right_tmp= p_ac3dec->dm_par.unit * *right++ + p_ac3dec->dm_par.slev * *right_sur++;
 241                                 *buffer++ = (s16)(left_tmp + *delay_left);
 242                                 *buffer++ = (s16)(right_tmp + *delay_right);
 243                                 *delay_left++ = p_ac3dec->dm_par.unit * *delay1_left++ + p_ac3dec->dm_par.slev * *delay1_sl;
 244                                 *delay_right++ = p_ac3dec->dm_par.unit * *delay1_right++ + p_ac3dec->dm_par.slev * *delay1_sl++;
 245                         }
 246                         break;
 247                 case 3:         /* 3/0 */
 248                         left = p_ac3dec->samples[0];
 249                         center = p_ac3dec->samples[1];
 250                         right = p_ac3dec->samples[2];
 251                         delay_left = p_ac3dec->imdct.delay[0];
 252                         delay_right = p_ac3dec->imdct.delay[1];
 253                         delay1_left = p_ac3dec->imdct.delay1[0];
 254                         delay1_center = p_ac3dec->imdct.delay1[1];
 255                         delay1_right = p_ac3dec->imdct.delay1[2];
 256
 257                         for (i = 0; i < 256; i++) {
 258                                 left_tmp = p_ac3dec->dm_par.unit * *left++  + p_ac3dec->dm_par.clev * *center;
 259                                 right_tmp= p_ac3dec->dm_par.unit * *right++ + p_ac3dec->dm_par.clev * *center++;
 260                                 *buffer++ = (s16)(left_tmp + *delay_left);
 261                                 *buffer++ = (s16)(right_tmp + *delay_right);
 262                                 *delay_left++ = p_ac3dec->dm_par.unit * *delay1_left++  + p_ac3dec->dm_par.clev * *delay1_center;
 263                                 *delay_right++ = p_ac3dec->dm_par.unit * *delay1_right++ + p_ac3dec->dm_par.clev * *center++;
 264                         }
 265                         break;
 266                 case 2:         /* copy to output */
 267                         for (i = 0; i < 256; i++) {
 268                                 *buffer++ = (s16)p_ac3dec->samples[0][i];
 269                                 *buffer++ = (s16)p_ac3dec->samples[1][i];
 270                         }
 271                         break;
 272                 }
 273         }
 274 }