code.delx.au - pulseaudio/blob - src/polypcore/sconv-s16le.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of polypaudio.
   5
   6   polypaudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU Lesser General Public License as published
   8   by the Free Software Foundation; either version 2 of the License,
   9   or (at your option) any later version.
  10
  11   polypaudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with polypaudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <assert.h>
  27 #include <inttypes.h>
  28
  29 #include <liboil/liboilfuncs.h>
  30
  31 #include "endianmacros.h"
  32 #include "sconv.h"
  33 #include "sconv-s16le.h"
  34 #include "log.h"
  35
  36 #ifndef INT16_FROM
  37 #define INT16_FROM INT16_FROM_LE
  38 #endif
  39
  40 #ifndef INT16_TO
  41 #define INT16_TO INT16_TO_LE
  42 #endif
  43
  44 #ifndef SWAP_WORDS
  45 #ifdef WORDS_BIGENDIAN
  46 #define SWAP_WORDS 1
  47 #else
  48 #define SWAP_WORDS 0
  49 #endif
  50 #endif
  51
  52 void pa_sconv_s16le_to_float32ne(unsigned n, const void *a, float *b) {
  53     const int16_t *ca = a;
  54
  55     assert(a);
  56     assert(b);
  57
  58 #if SWAP_WORDS == 1
  59
  60     for (; n > 0; n--) {
  61         int16_t s = *(ca++);
  62         *(b++) = ((float) INT16_FROM(s))/0x7FFF;
  63     }
  64
  65 #else
  66 {
  67     static const double add = 0, factor = 1.0/0x7FFF;
  68     oil_scaleconv_f32_s16(b, ca, n, &add, &factor);
  69 }
  70 #endif
  71 }
  72
  73 void pa_sconv_s16le_from_float32ne(unsigned n, const float *a, void *b) {
  74     int16_t *cb = b;
  75
  76     assert(a);
  77     assert(b);
  78
  79 #if SWAP_WORDS == 1
  80
  81     for (; n > 0; n--) {
  82         int16_t s;
  83         float v = *(a++);
  84
  85         if (v > 1)
  86             v = 1;
  87
  88         if (v < -1)
  89             v = -1;
  90
  91         s = (int16_t) (v * 0x7FFF);
  92         *(cb++) = INT16_TO(s);
  93     }
  94
  95 #else
  96 {
  97     static const double add = 0, factor = 0x7FFF;
  98     oil_scaleconv_s16_f32(cb, a, n, &add, &factor);
  99 }
 100 #endif
 101 }