AAC/SBR encoder improvements

* AAC-Encoder

  - AAC-ELD core encoder audio quality tuning. Update tuning tables, configure
    bitreservoir size and adapt afterburner iteration value.
     Modified file(s):
        libAACenc/src/aacenc.h
        libAACenc/src/aacenc_lib.cpp
        libAACenc/src/adj_thr.cpp
        libAACenc/src/adj_thr.h
        libAACenc/src/adj_thr_data.h
        libAACenc/src/bandwidth.cpp
        libAACenc/src/pnsparam.cpp
        libAACenc/src/qc_main.cpp

   - Introduze dead zone quantizer for ELD to improve audio quality at certain
     configurations.
     Modified file(s):
        libAACenc/src/aacenc_lib.cpp
        libAACenc/src/adj_thr.cpp
        libAACenc/src/adj_thr.h
        libAACenc/src/qc_data.h
        libAACenc/src/qc_main.cpp
        libAACenc/src/quantize.cpp
        libAACenc/src/quantize.h
        libAACenc/src/sf_estim.cpp
        libAACenc/src/sf_estim.h

   - Revise TNS module to improve ELD audio quality.
   - Use new window function and separate prediction gain according TNS filters.
   - Add missing memory initilization to TNS configuration.
     Modified file(s):
        libAACenc/src/aacenc_lib.cpp
        libAACenc/src/aacenc_tns.cpp
        libAACenc/src/aacenc_tns.h
        libAACenc/src/psy_main.cpp
        libAACenc/src/tns_func.h

* SBR-Encoder

   - Revise frequency resolution calculation and handle differently depending
     on number of envelopes and split frames decision.
   - Add and adjust ELD SBR tuning tables.
     Modified file(s):
        libSBRenc/include/sbr_encoder.h
        libSBRenc/src/bit_sbr.h
        libSBRenc/src/env_est.cpp
        libSBRenc/src/fram_gen.cpp
        libSBRenc/src/fram_gen.h
        libSBRenc/src/mh_det.cpp
        libSBRenc/src/sbr_def.h
        libSBRenc/src/sbr_encoder.cpp
        libSBRenc/src/sbr_rom.cpp
        libSBRenc/src/tran_det.cpp

   - Replace ELD transient detector with fast implementation.
     Modified file(s):
        libSBRenc/src/env_est.cpp
        libSBRenc/src/env_est.h
        libSBRenc/src/fram_gen.cpp
        libSBRenc/src/sbr_def.h
        libSBRenc/src/sbr_encoder.cpp
        libSBRenc/src/tran_det.cpp
        libSBRenc/src/tran_det.h

* FDK-Library
   - Introduce generic compare function in tools library.
     Modified file(s):
        libFDK/include/fixpoint_math.h
        libFDK/src/FDK_core.cpp

* SBR-Encoder

  -  Revise ELD frame splitter to improve bit distribution.
     Modified file(s):
        libSBRenc/include/sbr_encoder.h
        libSBRenc/src/bit_sbr.h
        libSBRenc/src/env_est.cpp
        libSBRenc/src/fram_gen.cpp
        libSBRenc/src/fram_gen.h
        libSBRenc/src/sbr_encoder.cpp
        libSBRenc/src/tran_det.cpp
        libSBRenc/src/tran_det.h

   - Configure amplitude resolution according the tonality of the audio signal.
     Modified file(s):
        libSBRenc/include/sbr_encoder.h
        libSBRenc/src/bit_sbr.h
        libSBRenc/src/env_est.cpp
        libSBRenc/src/nf_est.cpp
        libSBRenc/src/nf_est.h
        libSBRenc/src/sbr_def.h
        libSBRenc/src/sbr_encoder.cpp
        libSBRenc/src/ton_corr.cpp
        libSBRenc/src/ton_corr.h
        libSBRenc/src/tran_det.cpp
        libSBRenc/src/tran_det.h

Change-Id: Ie0672b989a06ee63b50240616b8d1d4b790b6cb2

1 files changed, 26 insertions, 6 deletions

diff --git a/libSBRenc/src/mh_det.cpp b/libSBRenc/src/mh_det.cpp
index 73d1b8b..bc80a15 100644
--- a/libSBRenc/src/mh_det.cpp
+++ b/libSBRenc/src/mh_det.cpp
@@ -2,7 +2,7 @@
 /* -----------------------------------------------------------------------------------------------------------
 Software License for The Fraunhofer FDK AAC Codec Library for Android
 
-© Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
+© Copyright  1995 - 2015 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
   All rights reserved.
 
  1.    INTRODUCTION
@@ -663,10 +663,27 @@ static void transientCleanUp(FIXP_DBL **quotaBuffer,
 }
 
 
-/**************************************************************************/
+/*****************************************************************************/
 /*!
-  \brief     Do detection for one tonality estimate.
+  \brief     Detection for one tonality estimate.
+
+  This is the actual missing harmonics detection, using information from the
+  previous detection.
+
+  If a missing harmonic was detected (in a previous frame) due to too high
+  tonality differences, but there was not enough tonality difference in the
+  current frame, the detection algorithm still continues to trace the strongest
+  tone in the scalefactor band (assuming that this is the tone that is going to
+  be replaced in the decoder). This is done to avoid abrupt endings of sines
+  fading out (e.g. in the glockenspiel).
+
+  The function also tries to estimate where one sine is going to be replaced
+  with multiple sines (due to the patching). This is done by comparing the
+  tonality flatness measure of the original and the SBR signal.
 
+  The function also tries to estimate (for the scalefactor bands only
+  containing one qmf subband) when a strong tone in the original will be
+  replaced by a strong tone in the adjacent QMF subband.
 
   \return    none.
 
@@ -694,10 +711,10 @@ static void detection(FIXP_DBL *quotaBuffer,
   for(i=0;i<nSfb;i++){
 
     thresTemp = (guideVectors.guideVectorDiff[i] != FL2FXCONST_DBL(0.0f))
-                  ? fixMax(fMult(mhThresh.decayGuideDiff,guideVectors.guideVectorDiff[i]), mhThresh.thresHoldDiffGuide)
+                  ? fMax(fMult(mhThresh.decayGuideDiff,guideVectors.guideVectorDiff[i]), mhThresh.thresHoldDiffGuide)
                   : mhThresh.thresHoldDiff;
 
-    thresTemp = fixMin(thresTemp, mhThresh.thresHoldDiff);
+    thresTemp = fMin(thresTemp, mhThresh.thresHoldDiff);
 
     if(pDiffVecScfb[i] > thresTemp){
       pHarmVec[i] = 1;
@@ -813,8 +830,11 @@ static void detectionWithPrediction(FIXP_DBL **quotaBuffer,
 
   if(newDetectionAllowed){
 
+    /* Since we don't want to use the transient region for detection (since the tonality values
+       tend to be a bit unreliable for this region) the guide-values are copied to the current
+       starting point. */
     if(totNoEst > 1){
-      start = detectionStart;
+      start = detectionStart+1;
 
       if (start != 0) {
         FDKmemcpy(guideVectors[start].guideVectorDiff,guideVectors[0].guideVectorDiff,nSfb*sizeof(FIXP_DBL));