Code

Random Number Generator

February 27, 20112 comments Coded in C for the SHARC

This is a random number generator that sounds pleasant in audo algorithms.  It does not have the nasty whistling present in the standard fortran random number generator that most people use.

// Random number generator that sounds pleasant in audio algorithms.
// The argument and return value is a 30-bit (positive nonzero) integer.
// This is Duttaro's 30-bit pseudorandom number generator, p.124 J.AES, vol 50 no 3 March 2002; 
// I found this 30-bit pseudorandom number generator sounds far superior to the 31-bit 
// pseudorandom number generator presented in the same article.
// To make result a signed fixed-point value, do not shift left into the sign bit;
// instead, subtract 0x20000000 then multiply by a scale factor.
#define NextRand(rr) (((((rr >> 16) ^ (rr >> 15) ^ (rr >> 1) ^ rr) & 1) << 29) | (rr >> 1))