1 files changed, 22 insertions, 1 deletions

diff --git a/apps/codecs/libspeex/math_approx.h b/apps/codecs/libspeex/math_approx.h
index 8421d634bb..4f61e8645a 100644
--- a/apps/codecs/libspeex/math_approx.h
+++ b/apps/codecs/libspeex/math_approx.h
@@ -45,8 +45,20 @@
 #define spx_cos_norm(x) (cos((.5f*M_PI)*(x)))
 #define spx_atan atan
 
-#endif
+/** Generate a pseudo-random number */
+static inline spx_word16_t speex_rand(spx_word16_t std, spx_int32_t *seed)
+{
+   const unsigned int jflone = 0x3f800000;
+   const unsigned int jflmsk = 0x007fffff;
+   union {int i; float f;} ran;
+   *seed = 1664525 * *seed + 1013904223;
+   ran.i = jflone | (jflmsk & *seed);
+   ran.f -= 1.5;
+   return 3.4642*std*ran.f;
+}
+
 
+#endif
 
 
 static inline spx_int16_t spx_ilog2(spx_uint32_t x)
@@ -106,6 +118,15 @@ static inline spx_int16_t spx_ilog4(spx_uint32_t x)
 
 #ifdef FIXED_POINT
 
+/** Generate a pseudo-random number */
+static inline spx_word16_t speex_rand(spx_word16_t std, spx_int32_t *seed)
+{
+   spx_word32_t res;
+   *seed = 1664525 * *seed + 1013904223;
+   res = MULT16_16(EXTRACT16(SHR32(*seed,16)),std);
+   return EXTRACT16(PSHR32(SUB32(res, SHR32(res, 3)),14));
+}
+
 /* sqrt(x) ~= 0.22178 + 1.29227*x - 0.77070*x^2 + 0.25723*x^3 (for .25 < x < 1) */
 /*#define C0 3634
 #define C1 21173