| /* ----------------------------------------------------------------------------- |
| Software License for The Fraunhofer FDK AAC Codec Library for Android |
| |
| © Copyright 1995 - 2018 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 |
| ----------------------------------------------------------------------------- */ |
| |
| /******************* Library for basic calculation routines ******************** |
| |
| Author(s): Manuel Jander, Josef Hoepfl, Youliy Ninov, Daniel Hagel |
| |
| Description: MDCT/MDST routines |
| |
| *******************************************************************************/ |
| |
| #ifndef MDCT_H |
| #define MDCT_H |
| |
| #include "common_fix.h" |
| |
| #define MDCT_OUT_HEADROOM 2 /* Output additional headroom */ |
| #define PCM_OUT_BITS SAMPLE_BITS |
| #define PCM_OUT_HEADROOM 8 /* Must have the same values as DMXH_HEADROOM */ |
| |
| #define MDCT_OUTPUT_SCALE (-MDCT_OUT_HEADROOM + (DFRACT_BITS - SAMPLE_BITS)) |
| /* Refer to "Output word length" in ISO/IEC 14496-3:2008(E) 23.2.3.6 */ |
| #define MDCT_OUTPUT_GAIN 16 |
| |
| #if (MDCT_OUTPUT_SCALE >= 0) |
| #define IMDCT_SCALE(x) SATURATE_RIGHT_SHIFT(x, MDCT_OUTPUT_SCALE, PCM_OUT_BITS) |
| #else |
| #define IMDCT_SCALE(x) SATURATE_LEFT_SHIFT(x, -MDCT_OUTPUT_SCALE, PCM_OUT_BITS) |
| #endif |
| #define IMDCT_SCALE_DBL(x) (FIXP_DBL)(x) |
| #define IMDCT_SCALE_DBL_LSH1(x) SATURATE_LEFT_SHIFT_ALT((x), 1, DFRACT_BITS) |
| |
| #define MLT_FLAG_CURR_ALIAS_SYMMETRY 1 |
| |
| typedef enum { |
| BLOCK_LONG = 0, /* normal long block */ |
| BLOCK_START, /* long start block */ |
| BLOCK_SHORT, /* 8 short blocks sequence */ |
| BLOCK_STOP /* long stop block*/ |
| } BLOCK_TYPE; |
| |
| typedef enum { SHAPE_SINE = 0, SHAPE_KBD, SHAPE_LOL } WINDOW_SHAPE; |
| |
| /** |
| * \brief MDCT persistent data |
| */ |
| typedef struct { |
| union { |
| FIXP_DBL *freq; |
| FIXP_DBL *time; |
| } overlap; /**< Pointer to overlap memory */ |
| |
| const FIXP_WTP *prev_wrs; /**< pointer to previous right window slope */ |
| int prev_tl; /**< previous transform length */ |
| int prev_nr; /**< previous right window offset */ |
| int prev_fr; /**< previous right window slope length */ |
| int ov_offset; /**< overlap time data fill level */ |
| int ov_size; /**< Overlap buffer size in words */ |
| |
| int prevAliasSymmetry; |
| int prevPrevAliasSymmetry; |
| |
| FIXP_DBL *pFacZir; |
| FIXP_DBL *pAsymOvlp; /**< pointer to asymmetric overlap (used for stereo LPD |
| transition) */ |
| } mdct_t; |
| |
| typedef mdct_t *H_MDCT; |
| |
| /** |
| * \brief Initialize as valid MDCT handle |
| * |
| * \param hMdct handle of an allocated MDCT handle. |
| * \param overlap pointer to FIXP_DBL overlap buffer. |
| * \param overlapBufferSize size in FIXP_DBLs of the given overlap buffer. |
| */ |
| void mdct_init(H_MDCT hMdct, FIXP_DBL *overlap, INT overlapBufferSize); |
| |
| /** |
| * \brief perform MDCT transform (time domain to frequency domain) with given |
| * parameters. |
| * |
| * \param hMdct handle of an allocated MDCT handle. |
| * \param pTimeData pointer to input time domain signal |
| * \param noInSamples number of input samples |
| * \param mdctData pointer to where the resulting MDCT spectrum will be stored |
| * into. |
| * \param nSpec number of spectra |
| * \param pMdctData_e pointer to the input data exponent. Updated accordingly on |
| * return for output data. |
| * \return number of input samples processed. |
| */ |
| INT mdct_block(H_MDCT hMdct, const INT_PCM *pTimeData, const INT noInSamples, |
| FIXP_DBL *RESTRICT mdctData, const INT nSpec, const INT tl, |
| const FIXP_WTP *pRightWindowPart, const INT fr, |
| SHORT *pMdctData_e); |
| |
| /** |
| * \brief add/multiply 2/N transform gain and MPEG4 part 3 defined output gain |
| * (see definition of MDCT_OUTPUT_GAIN) to given mantissa factor and exponent. |
| * \param pGain pointer to the mantissa of a gain factor to be applied to IMDCT |
| * data. |
| * \param pExponent pointer to the exponent of a gain factor to be applied to |
| * IMDCT data. |
| * \param tl length of the IMDCT where the gain *pGain * (2 ^ *pExponent) will |
| * be applied to. |
| */ |
| void imdct_gain(FIXP_DBL *pGain, int *pExponent, int tl); |
| |
| /** |
| * \brief drain buffered output samples into given buffer. Changes the MDCT |
| * state. |
| */ |
| INT imdct_drain(H_MDCT hMdct, FIXP_DBL *pTimeData, INT nrSamplesRoom); |
| |
| /** |
| * \brief Copy overlap time domain data to given buffer. Does not change the |
| * MDCT state. |
| * \return number of actually copied samples (ov + nr). |
| */ |
| INT imdct_copy_ov_and_nr(H_MDCT hMdct, FIXP_DBL *pTimeData, INT nrSamples); |
| |
| /** |
| * \brief Adapt MDCT parameters for non-matching window slopes. |
| * \param hMdct handle of an allocated MDCT handle. |
| * \param pfl pointer to left overlap window side length. |
| * \param pnl pointer to length of the left n part of the window. |
| * \param tl transform length. |
| * \param wls pointer to the left side overlap window coefficients. |
| * \param noOutSamples desired number of output samples. |
| */ |
| void imdct_adapt_parameters(H_MDCT hMdct, int *pfl, int *pnl, int tl, |
| const FIXP_WTP *wls, int noOutSamples); |
| |
| /** |
| * \brief perform several inverse MLT transforms (frequency domain to time |
| * domain) with given parameters. |
| * |
| * \param hMdct handle of an allocated MDCT handle. |
| * \param output pointer to where the output time domain signal will be stored |
| * into. |
| * \param spectrum pointer to the input MDCT spectra. |
| * \param scalefactors exponents of the input spectrum. |
| * \param nSpec number of MDCT spectrums. |
| * \param noOutSamples desired number of output samples. |
| * \param tl transform length. |
| * \param wls pointer to the left side overlap window coefficients. |
| * \param fl left overlap window side length. |
| * \param wrs pointer to the right side overlap window coefficients of all |
| * individual IMDCTs. |
| * \param fr right overlap window side length of all individual IMDCTs. |
| * \param gain factor to apply to output samples (if != 0). |
| * \param flags flags controlling the type of transform |
| * \return number of output samples returned. |
| */ |
| INT imlt_block(H_MDCT hMdct, FIXP_DBL *output, FIXP_DBL *spectrum, |
| const SHORT scalefactor[], const INT nSpec, |
| const INT noOutSamples, const INT tl, const FIXP_WTP *wls, |
| INT fl, const FIXP_WTP *wrs, const INT fr, FIXP_DBL gain, |
| int flags); |
| |
| #endif /* MDCT_H */ |