diff options
Diffstat (limited to 'libAACdec/src/block.h')
| -rw-r--r-- | libAACdec/src/block.h | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/libAACdec/src/block.h b/libAACdec/src/block.h new file mode 100644 index 0000000..a4ba085 --- /dev/null +++ b/libAACdec/src/block.h @@ -0,0 +1,260 @@ +/***************************** 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 */ |