apps/codecs/libwmapro/quant.h

   1 #ifndef _QUANT_H_
   2 #define _QUANT_H_
   3
   4 #include <inttypes.h>
   5
   6 /* This table contains unscaled integer casts of the floating point inverse
   7  * quantization factors used by wma pro. The formula for calculating the
   8  * floating point value is :
   9  *         quant = pow(10.0, exp/20)
  10  * 'exp' is an integer value which I have exmerimentally found to fall in the
  11  * range (50,170). */
  12 const int32_t quant_tab[121] = {
  13     0x0000013C, 0x00000163, 0x0000018E, 0x000001BF,
  14     0x000001F5, 0x00000232, 0x00000277, 0x000002C4,
  15     0x0000031A, 0x0000037B, 0x000003E8, 0x00000462,
  16     0x000004EB, 0x00000585, 0x00000631, 0x000006F2,
  17     0x000007CB, 0x000008BF, 0x000009D0, 0x00000B02,
  18     0x00000C5A, 0x00000DDC, 0x00000F8D, 0x00001173,
  19     0x00001394, 0x000015F7, 0x000018A6, 0x00001BA7,
  20     0x00001F07, 0x000022D1, 0x00002710, 0x00002BD4,
  21     0x0000312D, 0x0000372D, 0x00003DE9, 0x00004577,
  22     0x00004DF1, 0x00005773, 0x0000621F, 0x00006E18,
  23     0x00007B87, 0x00008A99, 0x00009B83, 0x0000AE7C,
  24     0x0000C3C7, 0x0000DBAA, 0x0000F678, 0x0001148B,
  25     0x00013649, 0x00015C25, 0x000186A0, 0x0001B64A,
  26     0x0001EBC5, 0x000227C6, 0x00026B19, 0x0002B6A4,
  27     0x00030B66, 0x00036A80, 0x0003D535, 0x00044CEE,
  28     0x0004D344, 0x000569FD, 0x0006131B, 0x0006D0DC,
  29     0x0007A5C3, 0x000894A5, 0x0009A0AD, 0x000ACD6A,
  30     0x000C1ED8, 0x000D9973, 0x000F4240, 0x00111EE2,
  31     0x001335AD, 0x00158DBA, 0x00182EFD, 0x001B2267,
  32     0x001E71FE, 0x00222901, 0x0026540E, 0x002B014F,
  33     0x003040A6, 0x003623E6, 0x003CBF10, 0x00442894,
  34     0x004C79A0, 0x0055CE75, 0x006046C5, 0x006C0622,
  35     0x00793472, 0x0087FE7D, 0x00989680, 0x00AB34D9,
  36     0x00C018C6, 0x00D7893F, 0x00F1D5E4, 0x010F580A,
  37     0x013073EF, 0x01559A0B, 0x017F4890, 0x01AE0D15,
  38     0x01E28679, 0x021D66FB, 0x025F769D, 0x02A995C7,
  39     0x02FCC043, 0x035A1095, 0x03C2C3B6, 0x04383D52,
  40     0x04BC0C77, 0x054FF0E6, 0x05F5E100, 0x06B01075,
  41     0x0780F7BD, 0x086B5C7A, 0x09725AE7, 0x0A997065,
  42     0x0BE48757, 0x0D580472, 0x0EF8D5A3, 0x10CC82D5,
  43     0x12D940B6
  44 };
  45
  46 #define EXP_MIN 50
  47 #define EXP_MAX 170
  48
  49 /* return the correct value of quant based on exp */
  50 #define QUANT(exp)    quant_tab[exp - EXP_MIN]
  51
  52
  53 #endif /* _QUANT_H_ */