Encoder downsampled SBR

* AAC-Encoder

   - Introduce optional AACENC_SBR_RATIO encoder API parameter to configure
     dualrate or downsampled SBR explicitely. ELD makes use of downsampled SBR
     in default configuration.
     Modified file(s):
        documentation\aacEncoder.pdf
        libAACenc\include\aacenc_lib.h
        libAACenc\src\aacenc.h
        libAACenc\src\aacenc_lib.cpp

* SBR-Encoder

   - Implement downsampled SBR feature.
   - Revise sbr tuning parameter selection.
     Modified file(s):
        libSBRenc\include\sbr_encoder.h
        libSBRenc\src\bit_sbr.h
        libSBRenc\src\env_est.cpp
        libSBRenc\src\mh_det.cpp
        libSBRenc\src\nf_est.cpp
        libSBRenc\src\ps_main.cpp
        libSBRenc\src\sbr.h
        libSBRenc\src\sbr_def.h
        libSBRenc\src\sbr_encoder.cpp
        libSBRenc\src\sbr_rom.cpp
        libSBRenc\src\sbr_rom.h
        libSBRenc\src\sbrenc_freq_sca.cpp
        libSBRenc\src\sbrenc_freq_sca.h
        libSBRenc\src\ton_corr.cpp

Bug 9428126

Change-Id: I731720a10829272acaaf70b84525df00a09ff3d2

1 files changed, 32 insertions, 19 deletions

diff --git a/libSBRenc/src/mh_det.cpp b/libSBRenc/src/mh_det.cpp
index 739dd74..73d1b8b 100644
--- a/libSBRenc/src/mh_det.cpp
+++ b/libSBRenc/src/mh_det.cpp
@@ -1244,25 +1244,38 @@ FDKsbrEnc_InitSbrMissingHarmonicsDetector (
 
   FDK_ASSERT(totNoEst <= MAX_NO_OF_ESTIMATES);
 
-  switch(frameSize){
-  case 2048:
-      hs->transientPosOffset = FRAME_MIDDLE_SLOT_2048;
-      hs->timeSlots          = NUMBER_TIME_SLOTS_2048;
-      break;
-  case 1920:
-      hs->transientPosOffset = FRAME_MIDDLE_SLOT_1920;
-      hs->timeSlots          = NUMBER_TIME_SLOTS_1920;
-      break;
-  case 1024:
-      hs->transientPosOffset = FRAME_MIDDLE_SLOT_512LD;
-      hs->timeSlots          = 16;
-      break;
-  case 960:
-      hs->transientPosOffset = FRAME_MIDDLE_SLOT_512LD;
-      hs->timeSlots          = 15;
-      break;
-  default:
-      return -1;
+  if (sbrSyntaxFlags & SBR_SYNTAX_LOW_DELAY)
+  {
+    switch(frameSize){
+    case 1024:
+    case 512:
+        hs->transientPosOffset = FRAME_MIDDLE_SLOT_512LD;
+        hs->timeSlots          = 16;
+        break;
+    case 960:
+    case 480:
+        hs->transientPosOffset = FRAME_MIDDLE_SLOT_512LD;
+        hs->timeSlots          = 15;
+        break;
+    default:
+        return -1;
+    }
+  } else
+  {
+    switch(frameSize){
+    case 2048:
+    case 1024:
+        hs->transientPosOffset = FRAME_MIDDLE_SLOT_2048;
+        hs->timeSlots          = NUMBER_TIME_SLOTS_2048;
+        break;
+    case 1920:
+    case 960:
+        hs->transientPosOffset = FRAME_MIDDLE_SLOT_1920;
+        hs->timeSlots          = NUMBER_TIME_SLOTS_1920;
+        break;
+    default:
+        return -1;
+    }
   }
 
   if (sbrSyntaxFlags & SBR_SYNTAX_LOW_DELAY) {