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Diffstat (limited to 'libSBRenc/src/resampler.h')
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diff --git a/libSBRenc/src/resampler.h b/libSBRenc/src/resampler.h new file mode 100644 index 0000000..29e170c --- /dev/null +++ b/libSBRenc/src/resampler.h @@ -0,0 +1,151 @@ + +/* ----------------------------------------------------------------------------------------------------------- +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 +----------------------------------------------------------------------------------------------------------- */ + +#ifndef __RESAMPLER_H +#define __RESAMPLER_H +/*! + \file + \brief Fixed Point Resampler Tool Box +*/ + +#include "common_fix.h" + + +/**************************************************************************/ +/* BIQUAD Filter Structure */ +/**************************************************************************/ + +#define MAXNR_SECTIONS (15) + +#ifdef RS_BIQUAD_STATES16 +typedef FIXP_SGL FIXP_BQS; +#else +typedef FIXP_DBL FIXP_BQS; +#endif + +typedef struct +{ + FIXP_BQS states[MAXNR_SECTIONS+1][2]; /*! state buffer */ + const FIXP_SGL *coeffa; /*! pointer to filter coeffs */ + FIXP_DBL gain; /*! overall gain factor */ + int Wc; /*! normalized cutoff freq * 1000 */ + int noCoeffs; /*! number of filter coeffs sets */ + int ptr; /*! index to rinbuffers */ +} LP_FILTER; + + +/**************************************************************************/ +/* Downsampler Structure */ +/**************************************************************************/ + +typedef struct +{ + LP_FILTER downFilter; /*! filter instance */ + int ratio; /*! downsampling ration */ + int delay; /*! downsampling delay (source fs) */ + int pending; /*! number of pending output samples */ +} DOWNSAMPLER; + + +/** + * \brief Initialized a given downsampler structure. + */ +INT FDKaacEnc_InitDownsampler(DOWNSAMPLER *DownSampler, /*!< pointer to downsampler instance */ + INT Wc, /*!< normalized cutoff freq * 1000 */ + INT ratio); /*!< downsampler ratio */ + +/** + * \brief Downsample a set of audio samples. numInSamples must be at least equal to the + * downsampler ratio. + */ +INT FDKaacEnc_Downsample(DOWNSAMPLER *DownSampler, /*!< pointer to downsampler instance */ + INT_PCM *inSamples, /*!< pointer to input samples */ + INT numInSamples, /*!< number of input samples */ + INT inStride, /*!< increment of input samples */ + INT_PCM *outSamples, /*!< pointer to output samples */ + INT *numOutSamples, /*!< pointer tp number of output samples */ + INT outstride); /*!< increment of output samples */ + + + +#endif /* __RESAMPLER_H */ |