Displaying 1 result from an estimated 1 matches for "38268343236508977175f".
2002 Aug 01
2
mdct.h - PI1_8, PI2_8 etc.
In vorbis/lib/mdct.h the following are defined:
for integer:
#define TRIGBITS 14
#define cPI3_8 6270
#define cPI2_8 11585
#define cPI1_8 15137
#define FLOAT_CONV(x) ((int)((x)*(1<<TRIGBITS)+.5))
for floats:
#define cPI3_8 .38268343236508977175F
#define cPI2_8 .70710678118654752441F
#define cPI1_8 .92387953251128675613F
#define FLOAT_CONV(x) = x
Could someone explain where these values come from? What's the significance
of TRIGBITS? It seems that the integer values are related to the floating
point values by q14 representation (multi...