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diff --git a/libFDK/include/dct.h b/libFDK/include/dct.h new file mode 100644 index 0000000..59b7319 --- /dev/null +++ b/libFDK/include/dct.h @@ -0,0 +1,147 @@ + +/* ----------------------------------------------------------------------------------------------------------- +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): + Description: Library functions to calculate standard DCTs. This will most + likely be replaced by hand-optimized functions for the specific + target processor. + +******************************************************************************/ + +#ifndef __dct_H +#define __dct_H + + + +#include "common_fix.h" + +/** + * \brief Calculate DCT type II of given length. The DCT IV is + * calculated by a complex FFT, with some pre and post twiddeling. + * A factor of sqrt(2/(N-1)) is NOT applied. + * \param pDat pointer to input/output data (in place processing). + * \param size size of pDat. + * \param pDat_e pointer to an integer containing the exponent of the data + * referenced by pDat. The exponent is updated accordingly. + */ +void dct_II(FIXP_DBL *pDat, FIXP_DBL *tmp, int size, int *pDat_e); + +/** + * \brief Calculate DCT type III of given length. The DCT IV is + * calculated by a complex FFT, with some pre and post twiddeling. + * Note that the factor 0.5 for the sum term x[0] is 1.0 instead of 0.5. + * A factor of sqrt(2/N) is NOT applied. + * \param pDat pointer to input/output data (in place processing). + * \param size size of pDat. + * \param pDat_e pointer to an integer containing the exponent of the data + * referenced by pDat. The exponent is updated accordingly. + */ +void dct_III(FIXP_DBL *pDat, FIXP_DBL *tmp, int size, int *pDat_e); + +/** + * \brief Calculate DCT type IV of given length. The DCT IV is + * calculated by a complex FFT, with some pre and post twiddeling. + * A factor of sqrt(2/N) is NOT applied. + * \param pDat pointer to input/output data (in place processing). + * \param size size of pDat. + * \param pDat_e pointer to an integer containing the exponent of the data + * referenced by pDat. The exponent is updated accordingly. + */ +void dct_IV(FIXP_DBL *pDat,int size, int *pDat_e); + +/** + * \brief Calculate DST type IV of given length. The DST IV is + * calculated by a complex FFT, with some pre and post twiddeling. + * A factor of sqrt(2/N) is NOT applied. + * \param pDat pointer to input/output data (in place processing). + * \param size size of pDat. + * \param pDat_e pointer to an integer containing the exponent of the data + * referenced by pDat. The exponent is updated accordingly. + */ +void dst_IV(FIXP_DBL *pDat,int size, int *pDat_e); + + + +#endif |