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diff --git a/libFDK/include/mdct.h b/libFDK/include/mdct.h new file mode 100644 index 0000000..0d04e4b --- /dev/null +++ b/libFDK/include/mdct.h @@ -0,0 +1,243 @@ + +/* ----------------------------------------------------------------------------------------------------------- +Software License for The Fraunhofer FDK AAC Codec Library for Android + +© Copyright 1995 - 2012 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 +----------------------------------------------------------------------------------------------------------- */ + +/*************************** Fraunhofer IIS FDK Tools ********************** + + Author(s): Manuel Jander, Josef Hoepfl + Description: MDCT routines + +******************************************************************************/ + +#ifndef __MDCT_H__ +#define __MDCT_H__ + + + +#include "common_fix.h" + +#define MDCT_OUT_HEADROOM 2 /* Output additional headroom */ +#define MDCT_OUTPUT_SCALE (DFRACT_BITS-SAMPLE_BITS-MDCT_OUT_HEADROOM) +/* Refer to "Output word length" in ISO/IEC 14496-3:2008(E) 23.2.3.6 */ +#define MDCT_OUTPUT_GAIN 16 + +#if (SAMPLE_BITS == DFRACT_BITS) +#define IMDCT_SCALE(x) (INT_PCM)SATURATE_LEFT_SHIFT(x, -MDCT_OUTPUT_SCALE, SAMPLE_BITS) +#else +#define IMDCT_SCALE(x) (INT_PCM)SATURATE_RIGHT_SHIFT(x, MDCT_OUTPUT_SCALE, SAMPLE_BITS) +#endif +#define IMDCT_SCALE_DBL(x) (FIXP_DBL)(x) + +/** + * \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 tranform 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 */ + +} 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. + * \return void + */ +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 spectrum pointer to where the resulting MDCT spectrum will be stored into. + * \param scalefactor pointer to the input scale shift value. Updated accordingly on return. + * \param input pointer to input time domain signal + * \param tl transformation length. + * \param nr right window slope offset (amount of window coefficients assumed to be 1.0) + * \param fr right overlap window slope length + * \param wrs pointer to the right side overlap window coefficients. + * \return number of input samples processed. + */ +INT mdct_block( + H_MDCT hMdct, + FIXP_DBL *spectrum, + INT *scalefactor, + INT_PCM *input, + INT tl, + INT nr, + INT fr, + const FIXP_WTB *wrs ); + + +/** + * \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 MDCT 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 stride the stride factor for accessing time domain samples in output. + * \param spectrum pointer to the input MDCT spectra. + * \param scalefactors scale shift values 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). + * \return number of output samples returned. + */ +INT imdct_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 ); + + +#endif /* __MDCT_H__ */ |