[FFmpeg-cvslog] r21924 - in trunk: libavcodec/acelp_pitch_delay.c libavutil/mathematics.h

[mru]

Author: mru
Date: Sat Feb 20 21:13:48 2010
New Revision: 21924

Log:
Replace log2f(10) with a constant

Modified:
   trunk/libavcodec/acelp_pitch_delay.c
   trunk/libavutil/mathematics.h

Modified: trunk/libavcodec/acelp_pitch_delay.c
==============================================================================
--- trunk/libavcodec/acelp_pitch_delay.c	Sat Feb 20 19:28:11 2010	(r21923)
+++ trunk/libavcodec/acelp_pitch_delay.c	Sat Feb 20 21:13:48 2010	(r21924)
@@ -128,7 +128,7 @@ float ff_amr_set_fixed_gain(float fixed_
     // ^g_c = ^gamma_gc * 100.05 (predicted dB + mean dB - dB of fixed vector)
     // Note 10^(0.05 * -10log(average x2)) = 1/sqrt((average x2)).
     float val = fixed_gain_factor *
-        exp2f(log2f(10.0) * 0.05 *
+        exp2f(M_LOG2_10 * 0.05 *
               (ff_dot_productf(pred_table, prediction_error, 4) +
                energy_mean)) /
         sqrtf(fixed_mean_energy);

Modified: trunk/libavutil/mathematics.h
==============================================================================
--- trunk/libavutil/mathematics.h	Sat Feb 20 19:28:11 2010	(r21923)
+++ trunk/libavutil/mathematics.h	Sat Feb 20 21:13:48 2010	(r21924)
@@ -35,6 +35,9 @@
 #ifndef M_LN10
 #define M_LN10         2.30258509299404568402  /* log_e 10 */
 #endif
+#ifndef M_LOG2_10
+#define M_LOG2_10      3.32192809488736218171  /* log_2 10 */
+#endif
 #ifndef M_PI
 #define M_PI           3.14159265358979323846  /* pi */
 #endif