apps/codecs/libatrac/fixp_math.h

   1 #include <stdlib.h>
   2 #include <inttypes.h>
   3
   4 /* Macros for converting between various fixed-point representations and floating point. */
   5 #define ONE_16 (1L << 16)
   6 #define fixtof64(x)       (float)((float)(x) / (float)(1 << 16))        //does not work on int64_t!
   7 #define ftofix32(x)       ((int32_t)((x) * (float)(1 << 16) + ((x) < 0 ? -0.5 : 0.5)))
   8 #define ftofix31(x)       ((int32_t)((x) * (float)(1 << 31) + ((x) < 0 ? -0.5 : 0.5)))
   9 #define fix31tof64(x)     (float)((float)(x) / (float)(1 << 31))
  10
  11 /* Fixed point math routines for use in atrac3.c */
  12 inline int32_t fixmul16(int32_t x, int32_t y);
  13 inline int32_t fixmul31(int32_t x, int32_t y);
  14 inline int32_t fixdiv16(int32_t x, int32_t y);
  15 inline int32_t fastSqrt(int32_t n);