Fraunhofer AAC codec.

License boilerplate update to follow.

Change-Id: I2810460c11a58b6d148d84673cc031f3685e79b5

1 files changed, 260 insertions, 0 deletions

diff --git a/libAACdec/src/block.h b/libAACdec/src/block.h
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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: long/short-block decoding
+
+   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.
+
+******************************************************************************/
+
+#ifndef BLOCK_H
+#define BLOCK_H
+
+#include "common_fix.h"
+
+#include "channelinfo.h"
+#include "FDK_bitstream.h"
+
+/* PNS (of block) */
+void CPns_Read (CPnsData *pPnsData,
+                HANDLE_FDK_BITSTREAM bs,
+                const CodeBookDescription *hcb,
+                SHORT *pScaleFactor,
+                UCHAR global_gain,
+                int band,
+                int group);
+
+
+void CPns_Apply (const CPnsData *pPnsData,
+                 const CIcsInfo *pIcsInfo,
+                 SPECTRAL_PTR pSpectrum,
+                 const SHORT    *pSpecScale,
+                 const SHORT    *pScaleFactor,
+                 const SamplingRateInfo *pSamplingRateInfo,
+                 const INT granuleLength,
+                 const int channel);
+
+
+
+/* TNS (of block) */
+/*!
+  \brief Read tns data-present flag from bitstream
+
+  The function reads the data-present flag for tns from
+  the bitstream.
+
+  \return  none
+*/
+void CTns_ReadDataPresentFlag(HANDLE_FDK_BITSTREAM bs,
+                              CTnsData *pTnsData);
+
+void CTns_ReadDataPresentUsac(
+        HANDLE_FDK_BITSTREAM hBs,
+        CTnsData *pTnsData0,
+        CTnsData *pTnsData1,
+        const CIcsInfo *pIcsInfo,
+        const UINT flags,
+        const int fCommonWindow
+        );
+
+AAC_DECODER_ERROR CTns_Read(HANDLE_FDK_BITSTREAM bs,
+                            CTnsData *pTnsData,
+                            const CIcsInfo *pIcsInfo,
+                            const UINT flags);
+
+void CTns_Apply ( CTnsData *RESTRICT pTnsData, /*!< pointer to aac decoder info */
+                  const CIcsInfo *pIcsInfo,
+                  SPECTRAL_PTR pSpectralCoefficient,
+                  const SamplingRateInfo *pSamplingRateInfo,
+                  const INT granuleLength);
+
+/* Block */
+
+LONG CBlock_GetEscape(HANDLE_FDK_BITSTREAM bs, const LONG q);
+
+/**
+ * \brief Read scale factor data. See chapter 4.6.2.3.2 of ISO/IEC 14496-3.
+ *        The SF_OFFSET = 100 value referenced in chapter 4.6.2.3.3 is already substracted
+ *        from the scale factor values. Also includes PNS data reading.
+ * \param bs bit stream handle data source
+ * \param pAacDecoderChannelInfo channel context info were decoded data is stored into.
+ * \param flags the decoder flags.
+ */
+AAC_DECODER_ERROR CBlock_ReadScaleFactorData(
+        CAacDecoderChannelInfo *pAacDecoderChannelInfo,
+        HANDLE_FDK_BITSTREAM bs,
+        const UINT flags
+        );
+
+/**
+ * \brief Read Huffman encoded spectral data.
+ * \param pAacDecoderChannelInfo channel context info.
+ * \param pSamplingRateInfo sampling rate info (sfb offsets).
+ * \param flags syntax flags.
+ */
+AAC_DECODER_ERROR  CBlock_ReadSpectralData(HANDLE_FDK_BITSTREAM bs,
+                                           CAacDecoderChannelInfo *pAacDecoderChannelInfo,
+                                           const SamplingRateInfo *pSamplingRateInfo,
+                                           const UINT  flags);
+
+
+AAC_DECODER_ERROR CBlock_ReadSectionData(HANDLE_FDK_BITSTREAM bs,
+                                         CAacDecoderChannelInfo *pAacDecoderChannelInfo,
+                                         const SamplingRateInfo *pSamplingRateInfo,
+                                         const UINT  flags);
+
+/**
+ * \brief find a common exponent (shift factor) for all sfb in each Spectral window, and store them into
+ *        CAacDecoderChannelInfo::specScale.
+ * \param pAacDecoderChannelInfo channel context info.
+ * \param pSamplingRateInfo sampling rate info (sfb offsets).
+ */
+void CBlock_ScaleSpectralData(CAacDecoderChannelInfo *pAacDecoderChannelInfo, SamplingRateInfo *pSamplingRateInfo);
+
+/**
+ * \brief Apply TNS and PNS tools.
+ */
+void ApplyTools ( CAacDecoderChannelInfo *pAacDecoderChannelInfo[],
+                  const SamplingRateInfo *pSamplingRateInfo,
+                  const UINT flags,
+                  const int channel );
+
+/**
+ * \brief Transform MDCT spectral data into time domain
+ */
+void CBlock_FrequencyToTime(CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo,
+                            CAacDecoderChannelInfo *pAacDecoderChannelInfo,
+                            INT_PCM outSamples[],
+                            const SHORT frameLen,
+                            const int stride,
+                            const int frameOk,
+                            FIXP_DBL *pWorkBuffer1);
+
+/**
+ * \brief Transform double lapped MDCT (AAC-ELD) spectral data into time domain.
+ */
+void CBlock_FrequencyToTimeLowDelay(CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo,
+                                    CAacDecoderChannelInfo *pAacDecoderChannelInfo,
+                                    INT_PCM outSamples[],
+                                    const short frameLen,
+                                    const char stride);
+
+AAC_DECODER_ERROR CBlock_InverseQuantizeSpectralData(CAacDecoderChannelInfo *pAacDecoderChannelInfo, SamplingRateInfo *pSamplingRateInfo);
+
+/**
+ * \brief Calculate 2^(lsb/4) * value^(4/3)
+ * \param pValue pointer to quantized value. The inverse quantized result is stored back here.
+ * \param lsb 2 LSBs of the scale factor (scaleFactor % 4) applied as power 2 factor to the
+ *        resulting inverse quantized value.
+ * \return the exponent of the result (mantissa) stored into *pValue.
+ */
+FDK_INLINE
+int EvaluatePower43 ( FIXP_DBL *pValue,
+                      UINT lsb )
+{
+  FIXP_DBL value;
+  UINT freeBits;
+  UINT exponent;
+
+  value = *pValue;
+  freeBits = fNormz (value) ;
+  exponent = DFRACT_BITS - freeBits ;
+  FDK_ASSERT (exponent < 14);
+
+  UINT x = (((int)value << freeBits) >> 19) ;
+  UINT tableIndex = (x & 0x0FFF) >> 4 ;
+  FIXP_DBL invQVal ;
+
+  x = x & 0x0F;
+
+  UINT r0=(LONG)InverseQuantTable [tableIndex+0];
+  UINT r1=(LONG)InverseQuantTable [tableIndex+1];
+  USHORT nx=16-x;
+  UINT temp=(r0)*nx+(r1)*x;
+  invQVal = (FIXP_DBL)temp;
+
+  FDK_ASSERT(lsb < 4);
+  *pValue = fMultDiv2 (invQVal, MantissaTable [lsb][exponent]) ;
+
+  /* + 1 compensates fMultDiv2(). */
+  return ExponentTable [lsb][exponent] + 1;
+}
+
+/**
+ * \brief determine the required shift scale for the given quantized value and scale (factor % 4) value.
+ */
+FDK_INLINE int GetScaleFromValue (FIXP_DBL value, unsigned int lsb)
+{
+  if (value!=(FIXP_DBL)0)
+  {
+    int scale = EvaluatePower43 (&value, lsb) ;
+    return CntLeadingZeros (value) - scale - 2 ;
+  }
+  else
+    return 0; /* Return zero, because its useless to scale a zero value, saves workload and avoids scaling overshifts. */
+}
+
+
+//#ifdef AACDEC_HUFFMANDECODER_ENABLE
+
+/*!
+  \brief Read huffman codeword
+
+  The function reads the huffman codeword from the bitstream and
+  returns the index value.
+
+  \return  index value
+*/
+inline int CBlock_DecodeHuffmanWord( HANDLE_FDK_BITSTREAM bs,                           /*!< pointer to bitstream */
+                                     const CodeBookDescription *hcb )                   /*!< pointer to codebook description */
+{
+  UINT val;
+  UINT index = 0;
+  const USHORT (*CodeBook) [HuffmanEntries] = hcb->CodeBook;
+
+  while (1)
+  {
+    val = CodeBook[index][FDKreadBits(bs,HuffmanBits)]; /* Expensive memory access */
+
+    if ((val & 1) == 0)
+    {
+      index = val>>2;
+      continue;
+    }
+    else
+    {
+      if (val & 2)
+      {
+        FDKpushBackCache(bs,1);
+      }
+
+      val >>= 2;
+      break;
+    }
+  }
+
+  return val;
+}
+
+//#endif /* AACDEC_HUFFMANDECODER_ENABLE */
+
+#endif /* #ifndef BLOCK_H */