diff options
Diffstat (limited to 'fdk-aac/libAACenc/src/chaosmeasure.cpp')
| -rw-r--r-- | fdk-aac/libAACenc/src/chaosmeasure.cpp | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/fdk-aac/libAACenc/src/chaosmeasure.cpp b/fdk-aac/libAACenc/src/chaosmeasure.cpp new file mode 100644 index 0000000..664284b --- /dev/null +++ b/fdk-aac/libAACenc/src/chaosmeasure.cpp @@ -0,0 +1,191 @@ +/* ----------------------------------------------------------------------------- +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 +----------------------------------------------------------------------------- */ + +/**************************** AAC encoder library ****************************** + + Author(s): M. Werner + + Description: Chaos measure calculation + +*******************************************************************************/ + +#include "chaosmeasure.h" + +/***************************************************************************** + functionname: FDKaacEnc_FDKaacEnc_CalculateChaosMeasurePeakFast + description: Eberlein method of chaos measure calculation by high-pass + filtering amplitude spectrum + A special case of FDKaacEnc_CalculateChaosMeasureTonalGeneric +-- highly optimized +*****************************************************************************/ +static void FDKaacEnc_FDKaacEnc_CalculateChaosMeasurePeakFast( + FIXP_DBL *RESTRICT paMDCTDataNM0, INT numberOfLines, + FIXP_DBL *RESTRICT chaosMeasure) { + INT i, j; + + /* calculate chaos measure by "peak filter" */ + /* make even and odd pass through data */ + FIXP_DBL left_0_div2, + center_0; /* left, center tap of filter, even numbered */ + FIXP_DBL left_1_div2, center_1; /* left, center tap of filter, odd numbered */ + + left_0_div2 = (FIXP_DBL)(((LONG)paMDCTDataNM0[0] ^ + ((LONG)paMDCTDataNM0[0] >> (DFRACT_BITS - 1))) >> + 1); + left_1_div2 = (FIXP_DBL)(((LONG)paMDCTDataNM0[1] ^ + ((LONG)paMDCTDataNM0[1] >> (DFRACT_BITS - 1))) >> + 1); + center_0 = (FIXP_DBL)((LONG)paMDCTDataNM0[2] ^ + ((LONG)paMDCTDataNM0[2] >> (DFRACT_BITS - 1))); + center_1 = (FIXP_DBL)((LONG)paMDCTDataNM0[3] ^ + ((LONG)paMDCTDataNM0[3] >> (DFRACT_BITS - 1))); + + for (j = 2; j < numberOfLines - 2; j += 2) { + FIXP_DBL right_0 = + (FIXP_DBL)((LONG)paMDCTDataNM0[j + 2] ^ + ((LONG)paMDCTDataNM0[j + 2] >> (DFRACT_BITS - 1))); + FIXP_DBL tmp_0 = left_0_div2 + (right_0 >> 1); + FIXP_DBL right_1 = + (FIXP_DBL)((LONG)paMDCTDataNM0[j + 3] ^ + ((LONG)paMDCTDataNM0[j + 3] >> (DFRACT_BITS - 1))); + FIXP_DBL tmp_1 = left_1_div2 + (right_1 >> 1); + + if (tmp_0 < center_0) { + INT leadingBits = CntLeadingZeros(center_0) - 1; + tmp_0 = schur_div(tmp_0 << leadingBits, center_0 << leadingBits, 8); + tmp_0 = fMult(tmp_0, tmp_0); + } else { + tmp_0 = (FIXP_DBL)MAXVAL_DBL; + } + chaosMeasure[j + 0] = tmp_0; + left_0_div2 = center_0 >> 1; + center_0 = right_0; + + if (tmp_1 < center_1) { + INT leadingBits = CntLeadingZeros(center_1) - 1; + tmp_1 = schur_div(tmp_1 << leadingBits, center_1 << leadingBits, 8); + tmp_1 = fMult(tmp_1, tmp_1); + } else { + tmp_1 = (FIXP_DBL)MAXVAL_DBL; + } + + left_1_div2 = center_1 >> 1; + center_1 = right_1; + chaosMeasure[j + 1] = tmp_1; + } + + /* provide chaos measure for first few lines */ + chaosMeasure[0] = chaosMeasure[2]; + chaosMeasure[1] = chaosMeasure[2]; + + /* provide chaos measure for last few lines */ + for (i = (numberOfLines - 3); i < numberOfLines; i++) + chaosMeasure[i] = FL2FXCONST_DBL(0.5); +} + +/***************************************************************************** + functionname: FDKaacEnc_CalculateChaosMeasure + description: calculates a chaosmeasure for every line, different methods + are available. 0 means tonal, 1 means noiselike + returns: + input: MDCT data, number of lines + output: chaosMeasure +*****************************************************************************/ +void FDKaacEnc_CalculateChaosMeasure(FIXP_DBL *paMDCTDataNM0, INT numberOfLines, + FIXP_DBL *chaosMeasure) + +{ + FDKaacEnc_FDKaacEnc_CalculateChaosMeasurePeakFast( + paMDCTDataNM0, numberOfLines, chaosMeasure); +} |