Author: cmcq
Date: Thu Jul 23 12:19:24 2009
New Revision: 4786
Log:
Copy a typo in the ref source
Modified:
amr/amrnbfloatdata.h
amr/amrnbfloatdec.c
Modified: amr/amrnbfloatdata.h
==============================================================================
--- amr/amrnbfloatdata.h Thu Jul 23 12:18:54 2009 (r4785)
+++ amr/amrnbfloatdata.h Thu Jul 23 12:19:24 2009 (r4786)
@@ -2302,6 +2302,10 @@ static const float gains_low[64][2] = {
// pre-processing tables
+// The specification says 0.8, which should be 13107, but the reference C code
+// uses 13017 instead. (Amusingly the same applies to SHARP_MAX in g729dec.c.)
+#define SHARP_MAX 0.79449462890625
+
// impulse response filter tables converted to float from Q15 int32_t used for
// anti-sparseness processing
static const float ir_filter_strong_MODE_795[AMR_SUBFRAME_SIZE] = {
Modified: amr/amrnbfloatdec.c
==============================================================================
--- amr/amrnbfloatdec.c Thu Jul 23 12:18:54 2009 (r4785)
+++ amr/amrnbfloatdec.c Thu Jul 23 12:19:24 2009 (r4786)
@@ -71,7 +71,7 @@ typedef struct AMRContext {
float pitch_gain[5]; ///< quantified pitch gains for
the current and previous four subframes
float fixed_gain[5]; ///< quantified fixed gains for
the current and previous four subframes
- float beta; ///< beta = previous pitch_gain,
bounded by [0.0,0.8]
+ float beta; ///< beta = previous pitch_gain,
bounded by [0.0,SHARP_MAX]
int diff_count; ///< the number of subframes for
which diff has been above 0.65
int hang_count; ///< the number of subframes
since a hangover period started
@@ -807,7 +807,7 @@ static void decode_gains(AMRContext *p,
// MODE_475 only updates on the 2nd and 4th subframes - this follows from
// the fact that the gains for two subframes are jointly quantised.
if (mode != MODE_475 || subframe & 1)
- p->beta = av_clipf(p->pitch_gain[4], 0.0, 0.8);
+ p->beta = av_clipf(p->pitch_gain[4], 0.0, SHARP_MAX);
// ^g_c = g_c' * ^gamma_gc
p->fixed_gain[4] = fixed_gain_factor
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