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diff --git a/fdk-aac/libFDK/include/mdct.h b/fdk-aac/libFDK/include/mdct.h new file mode 100644 index 0000000..1382374 --- /dev/null +++ b/fdk-aac/libFDK/include/mdct.h @@ -0,0 +1,253 @@ +/* ----------------------------------------------------------------------------- +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 */ |