| |
| /* ----------------------------------------------------------------------------------------------------------- |
| Software License for The Fraunhofer FDK AAC Codec Library for Android |
| |
| © Copyright 1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. |
| All rights reserved. |
| |
| 1. INTRODUCTION |
| The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements |
| the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio. |
| This FDK AAC Codec software is intended to be used on a wide variety of Android devices. |
| |
| AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual |
| audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by |
| independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part |
| of the MPEG specifications. |
| |
| Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer) |
| may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners |
| individually for the purpose of encoding or decoding bit streams in products that are compliant with |
| the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license |
| these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec |
| software may already be covered under those patent licenses when it is used for those licensed purposes only. |
| |
| Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality, |
| are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional |
| applications information and documentation. |
| |
| 2. COPYRIGHT LICENSE |
| |
| Redistribution and use in source and binary forms, with or without modification, are permitted without |
| payment of copyright license fees provided that you satisfy the following conditions: |
| |
| You must retain the complete text of this software license in redistributions of the FDK AAC Codec or |
| your modifications thereto in source code form. |
| |
| You must retain the complete text of this software license in the documentation and/or other materials |
| provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form. |
| You must make available free of charge copies of the complete source code of the FDK AAC Codec and your |
| modifications thereto to recipients of copies in binary form. |
| |
| The name of Fraunhofer may not be used to endorse or promote products derived from this library without |
| prior written permission. |
| |
| You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec |
| software or your modifications thereto. |
| |
| Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software |
| and the date of any change. For modified versions of the FDK AAC Codec, the term |
| "Fraunhofer FDK AAC Codec Library for Android" must be replaced by the term |
| "Third-Party Modified Version of the Fraunhofer FDK AAC Codec Library for Android." |
| |
| 3. NO PATENT LICENSE |
| |
| NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer, |
| ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with |
| respect to this software. |
| |
| You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized |
| by appropriate patent licenses. |
| |
| 4. DISCLAIMER |
| |
| This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright holders and contributors |
| "AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, including but not limited to the implied warranties |
| of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR |
| CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages, |
| including but not limited to procurement of substitute goods or services; loss of use, data, or profits, |
| or business interruption, however caused and on any theory of liability, whether in contract, strict |
| liability, or tort (including negligence), arising in any way out of the use of this software, even if |
| advised of the possibility of such damage. |
| |
| 5. CONTACT INFORMATION |
| |
| Fraunhofer Institute for Integrated Circuits IIS |
| Attention: Audio and Multimedia Departments - FDK AAC LL |
| Am Wolfsmantel 33 |
| 91058 Erlangen, Germany |
| |
| www.iis.fraunhofer.de/amm |
| amm-info@iis.fraunhofer.de |
| ----------------------------------------------------------------------------------------------------------- */ |
| |
| /*! |
| \file |
| \brief Envelope extraction prototypes |
| */ |
| |
| #ifndef __ENVELOPE_EXTRACTION_H |
| #define __ENVELOPE_EXTRACTION_H |
| |
| #include "sbrdecoder.h" |
| |
| #include "FDK_bitstream.h" |
| #include "lpp_tran.h" |
| |
| #include "psdec.h" |
| |
| #define ENV_EXP_FRACT 0 |
| /*!< Shift raw envelope data to support fractional numbers. |
| Can be set to 8 instead of 0 to enhance accuracy during concealment. |
| This is not required for conformance and #requantizeEnvelopeData() will |
| become more expensive. |
| */ |
| |
| #define EXP_BITS 6 |
| /*!< Size of exponent-part of a pseudo float envelope value (should be at least 6). |
| The remaining bits in each word are used for the mantissa (should be at least 10). |
| This format is used in the arrays iEnvelope[] and sbrNoiseFloorLevel[] |
| in the FRAME_DATA struct which must fit in a certain part of the output buffer |
| (See buffer management in sbr_dec.cpp). |
| Exponents and mantissas could also be stored in separate arrays. |
| Accessing the exponent or the mantissa would be simplified and the masks #MASK_E |
| resp. #MASK_M would no longer be required. |
| */ |
| |
| #define MASK_M (((1 << (FRACT_BITS - EXP_BITS)) - 1) << EXP_BITS) /*!< Mask for extracting the mantissa of a pseudo float envelope value */ |
| #define MASK_E ((1 << EXP_BITS) - 1) /*!< Mask for extracting the exponent of a pseudo float envelope value */ |
| |
| #define SIGN_EXT ( ((SCHAR)-1) ^ MASK_E) /*!< a CHAR-constant with all bits above our sign-bit set */ |
| #define ROUNDING ( (FIXP_SGL)(1<<(EXP_BITS-1)) ) /*!< 0.5-offset for rounding the mantissa of a pseudo-float envelope value */ |
| #define NRG_EXP_OFFSET 16 /*!< Will be added to the reference energy's exponent to prevent negative numbers */ |
| #define NOISE_EXP_OFFSET 38 /*!< Will be added to the noise level exponent to prevent negative numbers */ |
| |
| typedef enum |
| { |
| HEADER_NOT_PRESENT, |
| HEADER_OK, |
| HEADER_RESET |
| } |
| SBR_HEADER_STATUS; |
| |
| typedef enum |
| { |
| SBR_NOT_INITIALIZED, |
| UPSAMPLING, |
| SBR_HEADER, |
| SBR_ACTIVE |
| } |
| SBR_SYNC_STATE; |
| |
| |
| typedef enum |
| { |
| COUPLING_OFF = 0, |
| COUPLING_LEVEL, |
| COUPLING_BAL |
| } |
| COUPLING_MODE; |
| |
| typedef struct |
| { |
| UCHAR nSfb[2]; /*!< Number of SBR-bands for low and high freq-resolution */ |
| UCHAR nNfb; /*!< Actual number of noise bands to read from the bitstream*/ |
| UCHAR numMaster; /*!< Number of SBR-bands in v_k_master */ |
| UCHAR lowSubband; /*!< QMF-band where SBR frequency range starts */ |
| UCHAR highSubband; /*!< QMF-band where SBR frequency range ends */ |
| UCHAR limiterBandTable[MAX_NUM_LIMITERS+1]; /*!< Limiter band table. */ |
| UCHAR noLimiterBands; /*!< Number of limiter bands. */ |
| UCHAR nInvfBands; /*!< Number of bands for inverse filtering */ |
| UCHAR *freqBandTable[2]; /*!< Pointers to freqBandTableLo and freqBandTableHi */ |
| UCHAR freqBandTableLo[MAX_FREQ_COEFFS/2+1]; |
| /*!< Mapping of SBR bands to QMF bands for low frequency resolution */ |
| UCHAR freqBandTableHi[MAX_FREQ_COEFFS+1]; |
| /*!< Mapping of SBR bands to QMF bands for high frequency resolution */ |
| UCHAR freqBandTableNoise[MAX_NOISE_COEFFS+1]; |
| /*!< Mapping of SBR noise bands to QMF bands */ |
| UCHAR v_k_master[MAX_FREQ_COEFFS+1]; |
| /*!< Master BandTable which freqBandTable is derived from */ |
| } |
| FREQ_BAND_DATA; |
| |
| typedef FREQ_BAND_DATA *HANDLE_FREQ_BAND_DATA; |
| |
| #define SBRDEC_ELD_GRID 1 |
| #define SBRDEC_SYNTAX_SCAL 2 |
| #define SBRDEC_SYNTAX_USAC 4 |
| #define SBRDEC_SYNTAX_RSVD50 8 |
| #define SBRDEC_LOW_POWER 16 /* Flag indicating that Low Power QMF mode shall be used. */ |
| #define SBRDEC_PS_DECODED 32 /* Flag indicating that PS was decoded and rendered. */ |
| #define SBRDEC_LD_MPS_QMF 512 /* Flag indicating that the LD-MPS QMF shall be used. */ |
| #define SBRDEC_DOWNSAMPLE 8192 /* Flag indicating that the downsampling mode is used. */ |
| #define SBRDEC_FLUSH 16384 /* Flag is used to flush all elements in use. */ |
| #define SBRDEC_FORCE_RESET 32768 /* Flag is used to force a reset of all elements in use. */ |
| |
| #define SBRDEC_HDR_STAT_RESET 1 |
| #define SBRDEC_HDR_STAT_UPDATE 2 |
| |
| typedef struct { |
| UCHAR ampResolution; /*!< Amplitude resolution of envelope values (0: 1.5dB, 1: 3dB) */ |
| UCHAR xover_band; /*!< Start index in #v_k_master[] used for dynamic crossover frequency */ |
| UCHAR sbr_preprocessing; /*!< SBR prewhitening flag. */ |
| } SBR_HEADER_DATA_BS_INFO; |
| |
| typedef struct { |
| /* Changes in these variables causes a reset of the decoder */ |
| UCHAR startFreq; /*!< Index for SBR start frequency */ |
| UCHAR stopFreq; /*!< Index for SBR highest frequency */ |
| UCHAR freqScale; /*!< 0: linear scale, 1-3 logarithmic scales */ |
| UCHAR alterScale; /*!< Flag for coarser frequency resolution */ |
| UCHAR noise_bands; /*!< Noise bands per octave, read from bitstream*/ |
| |
| /* don't require reset */ |
| UCHAR limiterBands; /*!< Index for number of limiter bands per octave */ |
| UCHAR limiterGains; /*!< Index to select gain limit */ |
| UCHAR interpolFreq; /*!< Select gain calculation method (1: per QMF channel, 0: per SBR band) */ |
| UCHAR smoothingLength; /*!< Smoothing of gains over time (0: on 1: off) */ |
| |
| } SBR_HEADER_DATA_BS; |
| |
| typedef struct |
| { |
| SBR_SYNC_STATE syncState; /*!< The current initialization status of the header */ |
| |
| UCHAR status; /*!< Flags field used for signaling a reset right before the processing starts and an update from config (e.g. ASC). */ |
| UCHAR frameErrorFlag; /*!< Frame data valid flag. CAUTION: This variable will be overwritten by the flag stored in the element structure. |
| This is necessary because of the frame delay. There it might happen that different slots use the same header. */ |
| UCHAR numberTimeSlots; /*!< AAC: 16,15 */ |
| UCHAR numberOfAnalysisBands; /*!< Number of QMF analysis bands */ |
| UCHAR timeStep; /*!< Time resolution of SBR in QMF-slots */ |
| UINT sbrProcSmplRate; /*!< SBR processing sampling frequency (!= OutputSamplingRate) |
| (always: CoreSamplingRate * UpSamplingFactor; even in single rate mode) */ |
| |
| SBR_HEADER_DATA_BS bs_data; /*!< current SBR header. */ |
| SBR_HEADER_DATA_BS_INFO bs_info; /*!< SBR info. */ |
| |
| FREQ_BAND_DATA freqBandData; /*!< Pointer to struct #FREQ_BAND_DATA */ |
| } |
| SBR_HEADER_DATA; |
| |
| typedef SBR_HEADER_DATA *HANDLE_SBR_HEADER_DATA; |
| |
| |
| typedef struct |
| { |
| UCHAR frameClass; /*!< Select grid type */ |
| UCHAR nEnvelopes; /*!< Number of envelopes */ |
| UCHAR borders[MAX_ENVELOPES+1]; /*!< Envelope borders (in SBR-timeslots, e.g. mp3PRO: 0..11) */ |
| UCHAR freqRes[MAX_ENVELOPES]; /*!< Frequency resolution for each envelope (0=low, 1=high) */ |
| SCHAR tranEnv; /*!< Transient envelope, -1 if none */ |
| UCHAR nNoiseEnvelopes; /*!< Number of noise envelopes */ |
| UCHAR bordersNoise[MAX_NOISE_ENVELOPES+1];/*!< borders of noise envelopes */ |
| } |
| FRAME_INFO; |
| |
| |
| typedef struct |
| { |
| FIXP_SGL sfb_nrg_prev[MAX_FREQ_COEFFS]; /*!< Previous envelope (required for differential-coded values) */ |
| FIXP_SGL prevNoiseLevel[MAX_NOISE_COEFFS]; /*!< Previous noise envelope (required for differential-coded values) */ |
| COUPLING_MODE coupling; /*!< Stereo-mode of previous frame */ |
| INVF_MODE sbr_invf_mode[MAX_INVF_BANDS]; /*!< Previous strength of filtering in transposer */ |
| UCHAR ampRes; /*!< Previous amplitude resolution (0: 1.5dB, 1: 3dB) */ |
| UCHAR stopPos; /*!< Position in time where last envelope ended */ |
| UCHAR frameErrorFlag; /*!< Previous frame status */ |
| } |
| SBR_PREV_FRAME_DATA; |
| |
| typedef SBR_PREV_FRAME_DATA *HANDLE_SBR_PREV_FRAME_DATA; |
| |
| |
| typedef struct |
| { |
| int nScaleFactors; /*!< total number of scalefactors in frame */ |
| |
| FRAME_INFO frameInfo; /*!< time grid for current frame */ |
| UCHAR domain_vec[MAX_ENVELOPES]; /*!< Bitfield containing direction of delta-coding for each envelope (0:frequency, 1:time) */ |
| UCHAR domain_vec_noise[MAX_NOISE_ENVELOPES]; /*!< Same as above, but for noise envelopes */ |
| |
| INVF_MODE sbr_invf_mode[MAX_INVF_BANDS]; /*!< Strength of filtering in transposer */ |
| COUPLING_MODE coupling; /*!< Stereo-mode */ |
| int ampResolutionCurrentFrame; /*!< Amplitude resolution of envelope values (0: 1.5dB, 1: 3dB) */ |
| |
| UCHAR addHarmonics[MAX_FREQ_COEFFS]; /*!< Flags for synthetic sine addition */ |
| |
| FIXP_SGL iEnvelope[MAX_NUM_ENVELOPE_VALUES]; /*!< Envelope data */ |
| FIXP_SGL sbrNoiseFloorLevel[MAX_NUM_NOISE_VALUES]; /*!< Noise envelope data */ |
| } |
| SBR_FRAME_DATA; |
| |
| typedef SBR_FRAME_DATA *HANDLE_SBR_FRAME_DATA; |
| |
| void initSbrPrevFrameData (HANDLE_SBR_PREV_FRAME_DATA h_prev_data, |
| int timeSlots); |
| |
| |
| int sbrGetSingleChannelElement (HANDLE_SBR_HEADER_DATA hHeaderData, |
| HANDLE_SBR_FRAME_DATA hFrameData, |
| HANDLE_FDK_BITSTREAM hBitBuf, |
| HANDLE_PS_DEC hParametricStereoDec, |
| const UINT flags, |
| const int overlap |
| ); |
| |
| int sbrGetChannelPairElement (HANDLE_SBR_HEADER_DATA hHeaderData, |
| HANDLE_SBR_FRAME_DATA hFrameDataLeft, |
| HANDLE_SBR_FRAME_DATA hFrameDataRight, |
| HANDLE_FDK_BITSTREAM hBitBuf, |
| const UINT flags, |
| const int overlap); |
| |
| SBR_HEADER_STATUS |
| sbrGetHeaderData (HANDLE_SBR_HEADER_DATA headerData, |
| HANDLE_FDK_BITSTREAM hBitBuf, |
| const UINT flags, |
| const int fIsSbrData); |
| |
| /*! |
| \brief Initialize SBR header data |
| |
| Copy default values to the header data struct and patch some entries |
| depending on the core codec. |
| */ |
| SBR_ERROR |
| initHeaderData ( |
| HANDLE_SBR_HEADER_DATA hHeaderData, |
| const int sampleRateIn, |
| const int sampleRateOut, |
| const int samplesPerFrame, |
| const UINT flags |
| ); |
| #endif |
