Fraunhofer AAC codec.

License boilerplate update to follow.

Change-Id: I2810460c11a58b6d148d84673cc031f3685e79b5

1 files changed, 214 insertions, 0 deletions

diff --git a/libAACdec/src/channelinfo.cpp b/libAACdec/src/channelinfo.cpp
new file mode 100644
index 0000000..5c113aa
--- /dev/null
+++ b/libAACdec/src/channelinfo.cpp
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+/*****************************  MPEG-4 AAC Decoder  **************************
+
+                        (C) Copyright Fraunhofer IIS (2004)
+                               All Rights Reserved
+
+    Please be advised that this software and/or program delivery is
+    Confidential Information of Fraunhofer and subject to and covered by the
+
+    Fraunhofer IIS Software Evaluation Agreement
+    between Google Inc. and  Fraunhofer
+    effective and in full force since March 1, 2012.
+
+    You may use this software and/or program only under the terms and
+    conditions described in the above mentioned Fraunhofer IIS Software
+    Evaluation Agreement. Any other and/or further use requires a separate agreement.
+
+
+   $Id$
+   Author(s):   Josef Hoepfl
+   Description: individual channel stream info
+
+   This software and/or program is protected by copyright law and international
+   treaties. Any reproduction or distribution of this software and/or program,
+   or any portion of it, may result in severe civil and criminal penalties, and
+   will be prosecuted to the maximum extent possible under law.
+
+******************************************************************************/
+
+#include "channelinfo.h"
+#include "aac_rom.h"
+#include "aac_ram.h"
+#include "FDK_bitstream.h"
+
+
+AAC_DECODER_ERROR IcsReadMaxSfb (
+        HANDLE_FDK_BITSTREAM bs,
+        CIcsInfo *pIcsInfo,
+        const SamplingRateInfo *pSamplingRateInfo
+        )
+{
+  AAC_DECODER_ERROR ErrorStatus = AAC_DEC_OK;
+  int nbits;
+
+  if (IsLongBlock(pIcsInfo)) {
+    nbits = 6;
+    pIcsInfo->TotalSfBands = pSamplingRateInfo->NumberOfScaleFactorBands_Long;
+  } else {
+    nbits = 4;
+    pIcsInfo->TotalSfBands = pSamplingRateInfo->NumberOfScaleFactorBands_Short;
+  }
+  pIcsInfo->MaxSfBands = (UCHAR) FDKreadBits(bs, nbits);
+
+  if (pIcsInfo->MaxSfBands > pIcsInfo->TotalSfBands){
+    ErrorStatus = AAC_DEC_PARSE_ERROR;
+  }
+
+  return ErrorStatus;
+}
+
+
+
+AAC_DECODER_ERROR IcsRead(HANDLE_FDK_BITSTREAM bs,
+                          CIcsInfo *pIcsInfo,
+                          const SamplingRateInfo* pSamplingRateInfo,
+                          const UINT flags)
+{
+  AAC_DECODER_ERROR ErrorStatus = AAC_DEC_OK;
+
+  pIcsInfo->Valid = 0;
+
+  if (flags & AC_ELD){
+    pIcsInfo->WindowSequence = OnlyLongSequence;
+    pIcsInfo->WindowShape = 0;
+  }
+  else {
+    if ( !(flags & (AC_USAC|AC_RSVD50)) ) {
+      FDKreadBits(bs,1);
+    }
+    pIcsInfo->WindowSequence = (UCHAR) FDKreadBits(bs,2);
+    pIcsInfo->WindowShape = (UCHAR) FDKreadBits(bs,1);
+    if (flags & AC_LD) {
+      if (pIcsInfo->WindowShape) {
+        pIcsInfo->WindowShape = 2; /* select low overlap instead of KBD */
+      }
+    }
+  }
+
+  /* Sanity check */
+  if ( (flags & (AC_ELD|AC_LD)) && pIcsInfo->WindowSequence != OnlyLongSequence) {
+    pIcsInfo->WindowSequence = OnlyLongSequence;
+    ErrorStatus = AAC_DEC_PARSE_ERROR;
+    goto bail;
+  }
+
+  ErrorStatus = IcsReadMaxSfb(bs, pIcsInfo, pSamplingRateInfo);
+  if (ErrorStatus != AAC_DEC_OK) {
+    goto bail;
+  }
+
+  if (IsLongBlock(pIcsInfo))
+  {
+    if ( !(flags & (AC_ELD|AC_SCALABLE|AC_BSAC|AC_USAC|AC_RSVD50)) ) /* If not ELD nor Scalable nor BSAC nor USAC syntax then ... */
+    {
+      if ((UCHAR)FDKreadBits(bs,1) != 0 ) /* UCHAR PredictorDataPresent */
+      {
+        ErrorStatus = AAC_DEC_UNSUPPORTED_PREDICTION;
+        goto bail;
+      }
+    }
+
+    pIcsInfo->WindowGroups = 1;
+    pIcsInfo->WindowGroupLength[0] = 1;
+  }
+  else
+  {
+    INT i;
+    UINT mask;
+
+    pIcsInfo->ScaleFactorGrouping = (UCHAR) FDKreadBits(bs,7);
+
+    pIcsInfo->WindowGroups = 0 ;
+
+    for (i=0; i < (8-1); i++)
+    {
+      mask = 1 << (6 - i);
+      pIcsInfo->WindowGroupLength[i] = 1;
+
+      if (pIcsInfo->ScaleFactorGrouping & mask)
+      {
+        pIcsInfo->WindowGroupLength[pIcsInfo->WindowGroups]++;
+      }
+      else
+      {
+        pIcsInfo->WindowGroups++;
+      }
+    }
+
+    /* loop runs to i < 7 only */
+    pIcsInfo->WindowGroupLength[8-1] = 1;
+    pIcsInfo->WindowGroups++;
+  }
+
+
+bail:
+  if (ErrorStatus == AAC_DEC_OK)
+    pIcsInfo->Valid = 1;
+
+  return ErrorStatus;
+}
+
+
+/*
+  interleave codebooks the following way
+
+    9 (84w) |  1 (51w)
+   10 (82w) |  2 (39w)
+  SCL (65w) |  4 (38w)
+    3 (39w) |  5 (41w)
+            |  6 (40w)
+            |  7 (31w)
+            |  8 (31w)
+     (270w)     (271w)
+*/
+
+
+/*
+  Table entries are sorted as following:
+  | num_swb_long_window | sfbands_long | num_swb_short_window | sfbands_short |
+*/
+AAC_DECODER_ERROR getSamplingRateInfo(
+        SamplingRateInfo *t,
+        UINT samplesPerFrame,
+        UINT samplingRateIndex,
+        UINT samplingRate
+        )
+{
+  int index = 0;
+
+
+  t->samplingRateIndex = samplingRateIndex;
+  t->samplingRate = samplingRate;
+
+  switch (samplesPerFrame) {
+  case 1024:
+    index = 0;
+    break;
+  case 960:
+    index = 1;
+    break;
+  case 512:
+    index = 3;
+    break;
+  case 480:
+    index = 4;
+    break;
+
+  default:
+    return AAC_DEC_UNSUPPORTED_FORMAT;
+  }
+
+  t->ScaleFactorBands_Long = sfbOffsetTables[index][samplingRateIndex].sfbOffsetLong;
+  t->ScaleFactorBands_Short = sfbOffsetTables[index][samplingRateIndex].sfbOffsetShort;
+  t->NumberOfScaleFactorBands_Long = sfbOffsetTables[index][samplingRateIndex].numberOfSfbLong;
+  t->NumberOfScaleFactorBands_Short = sfbOffsetTables[index][samplingRateIndex].numberOfSfbShort;
+
+  if (t->ScaleFactorBands_Long == NULL || t->NumberOfScaleFactorBands_Long == 0) {
+    return AAC_DEC_UNSUPPORTED_FORMAT;
+  }
+
+  FDK_ASSERT(t->ScaleFactorBands_Long[t->NumberOfScaleFactorBands_Long] == samplesPerFrame);
+  FDK_ASSERT(t->ScaleFactorBands_Short == NULL || t->ScaleFactorBands_Short[t->NumberOfScaleFactorBands_Short]*8 == samplesPerFrame);
+
+  return AAC_DEC_OK;
+}