Encoder explicit signaling

* AAC-Encoder

   - Revise explicit signaling method which is required for downsampled SBR.
     The parameter is optional and default configuration is implicit signaling
     for dualrate SBR as before. In case of downsampled SBR and HE-AAC explicit
     signaling is configured as default.
     Modified file(s):
        documentation\aacEncoder.pdf
        libAACenc\include\aacenc_lib.h
        libAACenc\src\aacenc_lib.cpp
        libMpegTPEnc\src\tpenc_asc.cpp
        libMpegTPEnc\src\version
        libSYS\include\FDK_audio.h
        libSYS\src\genericStds.cpp

Bug 9428126

Change-Id: I35138140346f17384d109ee5829be9ea5bab80fc

1 files changed, 22 insertions, 2 deletions

diff --git a/libMpegTPEnc/src/tpenc_asc.cpp b/libMpegTPEnc/src/tpenc_asc.cpp
index 5ba71c8..3f10ca4 100644
--- a/libMpegTPEnc/src/tpenc_asc.cpp
+++ b/libMpegTPEnc/src/tpenc_asc.cpp
@@ -474,7 +474,7 @@ int transportEnc_writeASC (
         break;
   }
 
-  if (config->extAOT == AOT_SBR || config->extAOT == AOT_PS)
+  if (config->sbrSignaling==SIG_EXPLICIT_HIERARCHICAL && config->sbrPresent)
     writeAot(asc, config->extAOT);
   else
     writeAot(asc, config->aot);
@@ -492,7 +492,7 @@ int transportEnc_writeASC (
 
   FDKwriteBits( asc, getChannelConfig(config->channelMode), 4 );
 
-  if (config->extAOT == AOT_SBR || config->extAOT == AOT_PS) {
+  if (config->sbrSignaling==SIG_EXPLICIT_HIERARCHICAL && config->sbrPresent) {
     writeSampleRate(asc, config->extSamplingRate);
     writeAot(asc, config->aot);
   }
@@ -545,6 +545,26 @@ int transportEnc_writeASC (
       break;
   }
 
+  /* backward compatible explicit signaling of extension AOT */
+  if (config->sbrSignaling==SIG_EXPLICIT_BW_COMPATIBLE)
+  {
+    TP_ASC_EXTENSION_ID ascExtId = ASCEXT_UNKOWN;
+
+    if (config->sbrPresent) {
+      ascExtId=ASCEXT_SBR;
+      FDKwriteBits( asc, ascExtId, 11 );
+      writeAot(asc, config->extAOT);
+      FDKwriteBits( asc, 1, 1 ); /* sbrPresentFlag=1 */
+      writeSampleRate(asc, config->extSamplingRate);
+      if (config->psPresent) {
+        ascExtId=ASCEXT_PS;
+        FDKwriteBits( asc, ascExtId, 11 );
+        FDKwriteBits( asc, 1, 1 ); /* psPresentFlag=1 */
+      }
+    }
+
+  }
+
   /* Make sure all bits are sync'ed */
   FDKsyncCache( asc );