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Diffstat (limited to 'libSBRdec/src/env_dec.cpp')
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diff --git a/libSBRdec/src/env_dec.cpp b/libSBRdec/src/env_dec.cpp deleted file mode 100644 index 24b2d3b..0000000 --- a/libSBRdec/src/env_dec.cpp +++ /dev/null @@ -1,852 +0,0 @@ - -/* ----------------------------------------------------------------------------------------------------------- -Software License for The Fraunhofer FDK AAC Codec Library for Android - -© Copyright 1995 - 2013 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 ------------------------------------------------------------------------------------------------------------ */ - -/*! - \file - \brief envelope decoding - This module provides envelope decoding and error concealment algorithms. The main - entry point is decodeSbrData(). - - \sa decodeSbrData(),\ref documentationOverview -*/ - -#include "env_dec.h" - -#include "env_extr.h" -#include "transcendent.h" - -#include "genericStds.h" - - -static void decodeEnvelope (HANDLE_SBR_HEADER_DATA hHeaderData, - HANDLE_SBR_FRAME_DATA h_sbr_data, - HANDLE_SBR_PREV_FRAME_DATA h_prev_data, - HANDLE_SBR_PREV_FRAME_DATA h_prev_data_otherChannel); -static void sbr_envelope_unmapping (HANDLE_SBR_HEADER_DATA hHeaderData, - HANDLE_SBR_FRAME_DATA h_data_left, - HANDLE_SBR_FRAME_DATA h_data_right); -static void requantizeEnvelopeData (HANDLE_SBR_FRAME_DATA h_sbr_data, - int ampResolution); -static void deltaToLinearPcmEnvelopeDecoding (HANDLE_SBR_HEADER_DATA hHeaderData, - HANDLE_SBR_FRAME_DATA h_sbr_data, - HANDLE_SBR_PREV_FRAME_DATA h_prev_data); -static void decodeNoiseFloorlevels (HANDLE_SBR_HEADER_DATA hHeaderData, - HANDLE_SBR_FRAME_DATA h_sbr_data, - HANDLE_SBR_PREV_FRAME_DATA h_prev_data); -static void timeCompensateFirstEnvelope (HANDLE_SBR_HEADER_DATA hHeaderData, - HANDLE_SBR_FRAME_DATA h_sbr_data, - HANDLE_SBR_PREV_FRAME_DATA h_prev_data); -static int checkEnvelopeData (HANDLE_SBR_HEADER_DATA hHeaderData, - HANDLE_SBR_FRAME_DATA h_sbr_data, - HANDLE_SBR_PREV_FRAME_DATA h_prev_data); - - - -#define SBR_ENERGY_PAN_OFFSET (12 << ENV_EXP_FRACT) -#define SBR_MAX_ENERGY (35 << ENV_EXP_FRACT) - -#define DECAY ( 1 << ENV_EXP_FRACT) - -#if ENV_EXP_FRACT -#define DECAY_COUPLING ( 1 << (ENV_EXP_FRACT-1) ) /*!< corresponds to a value of 0.5 */ -#else -#define DECAY_COUPLING 1 /*!< If the energy data is not shifted, use 1 instead of 0.5 */ -#endif - - -/*! - \brief Convert table index -*/ -static int indexLow2High(int offset, /*!< mapping factor */ - int index, /*!< index to scalefactor band */ - int res) /*!< frequency resolution */ -{ - if(res == 0) - { - if (offset >= 0) - { - if (index < offset) - return(index); - else - return(2*index - offset); - } - else - { - offset = -offset; - if (index < offset) - return(2*index+index); - else - return(2*index + offset); - } - } - else - return(index); -} - - -/*! - \brief Update previous envelope value for delta-coding - - The current envelope values needs to be stored for delta-coding - in the next frame. The stored envelope is always represented with - the high frequency resolution. If the current envelope uses the - low frequency resolution, the energy value will be mapped to the - corresponding high-res bands. -*/ -static void mapLowResEnergyVal(FIXP_SGL currVal, /*!< current energy value */ - FIXP_SGL* prevData,/*!< pointer to previous data vector */ - int offset, /*!< mapping factor */ - int index, /*!< index to scalefactor band */ - int res) /*!< frequeny resolution */ -{ - if(res == 0) - { - if (offset >= 0) - { - if(index < offset) - prevData[index] = currVal; - else - { - prevData[2*index - offset] = currVal; - prevData[2*index+1 - offset] = currVal; - } - } - else - { - offset = -offset; - if (index < offset) - { - prevData[3*index] = currVal; - prevData[3*index+1] = currVal; - prevData[3*index+2] = currVal; - } - else - { - prevData[2*index + offset] = currVal; - prevData[2*index + 1 + offset] = currVal; - } - } - } - else - prevData[index] = currVal; -} - - - -/*! - \brief Convert raw envelope and noisefloor data to energy levels - - This function is being called by sbrDecoder_ParseElement() and provides two important algorithms: - - First the function decodes envelopes and noise floor levels as described in requantizeEnvelopeData() - and sbr_envelope_unmapping(). The function also implements concealment algorithms in case there are errors - within the sbr data. For both operations fractional arithmetic is used. - Therefore you might encounter different output values on your target - system compared to the reference implementation. -*/ -void -decodeSbrData (HANDLE_SBR_HEADER_DATA hHeaderData, /*!< Static control data */ - HANDLE_SBR_FRAME_DATA h_data_left, /*!< pointer to left channel frame data */ - HANDLE_SBR_PREV_FRAME_DATA h_prev_data_left, /*!< pointer to left channel previous frame data */ - HANDLE_SBR_FRAME_DATA h_data_right, /*!< pointer to right channel frame data */ - HANDLE_SBR_PREV_FRAME_DATA h_prev_data_right)/*!< pointer to right channel previous frame data */ -{ - FIXP_SGL tempSfbNrgPrev[MAX_FREQ_COEFFS]; - int errLeft; - - /* Save previous energy values to be able to reuse them later for concealment. */ - FDKmemcpy (tempSfbNrgPrev, h_prev_data_left->sfb_nrg_prev, MAX_FREQ_COEFFS * sizeof(FIXP_SGL)); - - decodeEnvelope (hHeaderData, h_data_left, h_prev_data_left, h_prev_data_right); - decodeNoiseFloorlevels (hHeaderData, h_data_left, h_prev_data_left); - - if(h_data_right != NULL) { - errLeft = hHeaderData->frameErrorFlag; - decodeEnvelope (hHeaderData, h_data_right, h_prev_data_right, h_prev_data_left); - decodeNoiseFloorlevels (hHeaderData, h_data_right, h_prev_data_right); - - if (!errLeft && hHeaderData->frameErrorFlag) { - /* If an error occurs in the right channel where the left channel seemed ok, - we apply concealment also on the left channel. This ensures that the coupling - modes of both channels match and that we have the same number of envelopes in - coupling mode. - However, as the left channel has already been processed before, the resulting - energy levels are not the same as if the left channel had been concealed - during the first call of decodeEnvelope(). - */ - /* Restore previous energy values for concealment, because the values have been - overwritten by the first call of decodeEnvelope(). */ - FDKmemcpy (h_prev_data_left->sfb_nrg_prev, tempSfbNrgPrev, MAX_FREQ_COEFFS * sizeof(FIXP_SGL)); - /* Do concealment */ - decodeEnvelope (hHeaderData, h_data_left, h_prev_data_left, h_prev_data_right); - } - - if (h_data_left->coupling) { - sbr_envelope_unmapping (hHeaderData, h_data_left, h_data_right); - } - } - - /* Display the data for debugging: */ -} - - -/*! - \brief Convert from coupled channels to independent L/R data -*/ -static void -sbr_envelope_unmapping (HANDLE_SBR_HEADER_DATA hHeaderData, /*!< Static control data */ - HANDLE_SBR_FRAME_DATA h_data_left, /*!< pointer to left channel */ - HANDLE_SBR_FRAME_DATA h_data_right) /*!< pointer to right channel */ -{ - int i; - FIXP_SGL tempL_m, tempR_m, tempRplus1_m, newL_m, newR_m; - SCHAR tempL_e, tempR_e, tempRplus1_e, newL_e, newR_e; - - - /* 1. Unmap (already dequantized) coupled envelope energies */ - - for (i = 0; i < h_data_left->nScaleFactors; i++) { - tempR_m = (FIXP_SGL)((LONG)h_data_right->iEnvelope[i] & MASK_M); - tempR_e = (SCHAR)((LONG)h_data_right->iEnvelope[i] & MASK_E); - - tempR_e -= (18 + NRG_EXP_OFFSET); /* -18 = ld(UNMAPPING_SCALE / h_data_right->nChannels) */ - tempL_m = (FIXP_SGL)((LONG)h_data_left->iEnvelope[i] & MASK_M); - tempL_e = (SCHAR)((LONG)h_data_left->iEnvelope[i] & MASK_E); - - tempL_e -= NRG_EXP_OFFSET; - - /* Calculate tempRight+1 */ - FDK_add_MantExp( tempR_m, tempR_e, - FL2FXCONST_SGL(0.5f), 1, /* 1.0 */ - &tempRplus1_m, &tempRplus1_e); - - FDK_divide_MantExp( tempL_m, tempL_e+1, /* 2 * tempLeft */ - tempRplus1_m, tempRplus1_e, - &newR_m, &newR_e ); - - if (newR_m >= ((FIXP_SGL)MAXVAL_SGL - ROUNDING)) { - newR_m >>= 1; - newR_e += 1; - } - - newL_m = FX_DBL2FX_SGL(fMult(tempR_m,newR_m)); - newL_e = tempR_e + newR_e; - - h_data_right->iEnvelope[i] = ((FIXP_SGL)((SHORT)(FIXP_SGL)(newR_m + ROUNDING) & MASK_M)) + - (FIXP_SGL)((SHORT)(FIXP_SGL)(newR_e + NRG_EXP_OFFSET) & MASK_E); - h_data_left->iEnvelope[i] = ((FIXP_SGL)((SHORT)(FIXP_SGL)(newL_m + ROUNDING) & MASK_M)) + - (FIXP_SGL)((SHORT)(FIXP_SGL)(newL_e + NRG_EXP_OFFSET) & MASK_E); - } - - /* 2. Dequantize and unmap coupled noise floor levels */ - - for (i = 0; i < hHeaderData->freqBandData.nNfb * h_data_left->frameInfo.nNoiseEnvelopes; i++) { - - tempL_e = (SCHAR)(6 - (LONG)h_data_left->sbrNoiseFloorLevel[i]); - tempR_e = (SCHAR)((LONG)h_data_right->sbrNoiseFloorLevel[i] - 12) /*SBR_ENERGY_PAN_OFFSET*/; - - /* Calculate tempR+1 */ - FDK_add_MantExp( FL2FXCONST_SGL(0.5f), 1+tempR_e, /* tempR */ - FL2FXCONST_SGL(0.5f), 1, /* 1.0 */ - &tempRplus1_m, &tempRplus1_e); - - /* Calculate 2*tempLeft/(tempR+1) */ - FDK_divide_MantExp( FL2FXCONST_SGL(0.5f), tempL_e+2, /* 2 * tempLeft */ - tempRplus1_m, tempRplus1_e, - &newR_m, &newR_e ); - - /* if (newR_m >= ((FIXP_SGL)MAXVAL_SGL - ROUNDING)) { - newR_m >>= 1; - newR_e += 1; - } */ - - /* L = tempR * R */ - newL_m = newR_m; - newL_e = newR_e + tempR_e; - h_data_right->sbrNoiseFloorLevel[i] = ((FIXP_SGL)((SHORT)(FIXP_SGL)(newR_m + ROUNDING) & MASK_M)) + - (FIXP_SGL)((SHORT)(FIXP_SGL)(newR_e + NOISE_EXP_OFFSET) & MASK_E); - h_data_left->sbrNoiseFloorLevel[i] = ((FIXP_SGL)((SHORT)(FIXP_SGL)(newL_m + ROUNDING) & MASK_M)) + - (FIXP_SGL)((SHORT)(FIXP_SGL)(newL_e + NOISE_EXP_OFFSET) & MASK_E); - } -} - - -/*! - \brief Simple alternative to the real SBR concealment - - If the real frameInfo is not available due to a frame loss, a replacement will - be constructed with 1 envelope spanning the whole frame (FIX-FIX). - The delta-coded energies are set to negative values, resulting in a fade-down. - In case of coupling, the balance-channel will move towards the center. -*/ -static void -leanSbrConcealment(HANDLE_SBR_HEADER_DATA hHeaderData, /*!< Static control data */ - HANDLE_SBR_FRAME_DATA h_sbr_data, /*!< pointer to current data */ - HANDLE_SBR_PREV_FRAME_DATA h_prev_data /*!< pointer to data of last frame */ - ) -{ - FIXP_SGL target; /* targeted level for sfb_nrg_prev during fade-down */ - FIXP_SGL step; /* speed of fade */ - int i; - - int currentStartPos = h_prev_data->stopPos - hHeaderData->numberTimeSlots; - int currentStopPos = hHeaderData->numberTimeSlots; - - - /* Use some settings of the previous frame */ - h_sbr_data->ampResolutionCurrentFrame = h_prev_data->ampRes; - h_sbr_data->coupling = h_prev_data->coupling; - for(i=0;i<MAX_INVF_BANDS;i++) - h_sbr_data->sbr_invf_mode[i] = h_prev_data->sbr_invf_mode[i]; - - /* Generate concealing control data */ - - h_sbr_data->frameInfo.nEnvelopes = 1; - h_sbr_data->frameInfo.borders[0] = currentStartPos; - h_sbr_data->frameInfo.borders[1] = currentStopPos; - h_sbr_data->frameInfo.freqRes[0] = 1; - h_sbr_data->frameInfo.tranEnv = -1; /* no transient */ - h_sbr_data->frameInfo.nNoiseEnvelopes = 1; - h_sbr_data->frameInfo.bordersNoise[0] = currentStartPos; - h_sbr_data->frameInfo.bordersNoise[1] = currentStopPos; - - h_sbr_data->nScaleFactors = hHeaderData->freqBandData.nSfb[1]; - - /* Generate fake envelope data */ - - h_sbr_data->domain_vec[0] = 1; - - if (h_sbr_data->coupling == COUPLING_BAL) { - target = (FIXP_SGL)SBR_ENERGY_PAN_OFFSET; - step = (FIXP_SGL)DECAY_COUPLING; - } - else { - target = FL2FXCONST_SGL(0.0f); - step = (FIXP_SGL)DECAY; - } - if (hHeaderData->bs_info.ampResolution == 0) { - target <<= 1; - step <<= 1; - } - - for (i=0; i < h_sbr_data->nScaleFactors; i++) { - if (h_prev_data->sfb_nrg_prev[i] > target) - h_sbr_data->iEnvelope[i] = -step; - else - h_sbr_data->iEnvelope[i] = step; - } - - /* Noisefloor levels are always cleared ... */ - - h_sbr_data->domain_vec_noise[0] = 1; - for (i=0; i < hHeaderData->freqBandData.nNfb; i++) - h_sbr_data->sbrNoiseFloorLevel[i] = FL2FXCONST_SGL(0.0f); - - /* ... and so are the sines */ - FDKmemclear(h_sbr_data->addHarmonics, MAX_FREQ_COEFFS); -} - - -/*! - \brief Build reference energies and noise levels from bitstream elements -*/ -static void -decodeEnvelope (HANDLE_SBR_HEADER_DATA hHeaderData, /*!< Static control data */ - HANDLE_SBR_FRAME_DATA h_sbr_data, /*!< pointer to current data */ - HANDLE_SBR_PREV_FRAME_DATA h_prev_data, /*!< pointer to data of last frame */ - HANDLE_SBR_PREV_FRAME_DATA otherChannel /*!< other channel's last frame data */ - ) -{ - int i; - int fFrameError = hHeaderData->frameErrorFlag; - FIXP_SGL tempSfbNrgPrev[MAX_FREQ_COEFFS]; - - if (!fFrameError) { - /* - To avoid distortions after bad frames, set the error flag if delta coding in time occurs. - However, SBR can take a little longer to come up again. - */ - if ( h_prev_data->frameErrorFlag ) { - if (h_sbr_data->domain_vec[0] != 0) { - fFrameError = 1; - } - } else { - /* Check that the previous stop position and the current start position match. - (Could be done in checkFrameInfo(), but the previous frame data is not available there) */ - if ( h_sbr_data->frameInfo.borders[0] != h_prev_data->stopPos - hHeaderData->numberTimeSlots ) { - /* Both the previous as well as the current frame are flagged to be ok, but they do not match! */ - if (h_sbr_data->domain_vec[0] == 1) { - /* Prefer concealment over delta-time coding between the mismatching frames */ - fFrameError = 1; - } - else { - /* Close the gap in time by triggering timeCompensateFirstEnvelope() */ - fFrameError = 1; - } - } - } - } - - - if (fFrameError) /* Error is detected */ - { - leanSbrConcealment(hHeaderData, - h_sbr_data, - h_prev_data); - - /* decode the envelope data to linear PCM */ - deltaToLinearPcmEnvelopeDecoding (hHeaderData, h_sbr_data, h_prev_data); - } - else /*Do a temporary dummy decoding and check that the envelope values are within limits */ - { - if (h_prev_data->frameErrorFlag) { - timeCompensateFirstEnvelope (hHeaderData, h_sbr_data, h_prev_data); - if (h_sbr_data->coupling != h_prev_data->coupling) { - /* - Coupling mode has changed during concealment. - The stored energy levels need to be converted. - */ - for (i = 0; i < hHeaderData->freqBandData.nSfb[1]; i++) { - /* Former Level-Channel will be used for both channels */ - if (h_prev_data->coupling == COUPLING_BAL) - h_prev_data->sfb_nrg_prev[i] = otherChannel->sfb_nrg_prev[i]; - /* Former L/R will be combined as the new Level-Channel */ - else if (h_sbr_data->coupling == COUPLING_LEVEL) - h_prev_data->sfb_nrg_prev[i] = (h_prev_data->sfb_nrg_prev[i] + otherChannel->sfb_nrg_prev[i]) >> 1; - else if (h_sbr_data->coupling == COUPLING_BAL) - h_prev_data->sfb_nrg_prev[i] = (FIXP_SGL)SBR_ENERGY_PAN_OFFSET; - } - } - } - FDKmemcpy (tempSfbNrgPrev, h_prev_data->sfb_nrg_prev, - MAX_FREQ_COEFFS * sizeof (FIXP_SGL)); - - deltaToLinearPcmEnvelopeDecoding (hHeaderData, h_sbr_data, h_prev_data); - - fFrameError = checkEnvelopeData (hHeaderData, h_sbr_data, h_prev_data); - - if (fFrameError) - { - hHeaderData->frameErrorFlag = 1; - FDKmemcpy (h_prev_data->sfb_nrg_prev, tempSfbNrgPrev, - MAX_FREQ_COEFFS * sizeof (FIXP_SGL)); - decodeEnvelope (hHeaderData, h_sbr_data, h_prev_data, otherChannel); - return; - } - } - - requantizeEnvelopeData (h_sbr_data, h_sbr_data->ampResolutionCurrentFrame); - - hHeaderData->frameErrorFlag = fFrameError; -} - - -/*! - \brief Verify that envelope energies are within the allowed range - \return 0 if all is fine, 1 if an envelope value was too high -*/ -static int -checkEnvelopeData (HANDLE_SBR_HEADER_DATA hHeaderData, /*!< Static control data */ - HANDLE_SBR_FRAME_DATA h_sbr_data, /*!< pointer to current data */ - HANDLE_SBR_PREV_FRAME_DATA h_prev_data /*!< pointer to data of last frame */ - ) -{ - FIXP_SGL *iEnvelope = h_sbr_data->iEnvelope; - FIXP_SGL *sfb_nrg_prev = h_prev_data->sfb_nrg_prev; - int i = 0, errorFlag = 0; - FIXP_SGL sbr_max_energy = - (h_sbr_data->ampResolutionCurrentFrame == 1) ? SBR_MAX_ENERGY : (SBR_MAX_ENERGY << 1); - - /* - Range check for current energies - */ - for (i = 0; i < h_sbr_data->nScaleFactors; i++) { - if (iEnvelope[i] > sbr_max_energy) { - errorFlag = 1; - } - if (iEnvelope[i] < FL2FXCONST_SGL(0.0f)) { - errorFlag = 1; - /* iEnvelope[i] = FL2FXCONST_SGL(0.0f); */ - } - } - - /* - Range check for previous energies - */ - for (i = 0; i < hHeaderData->freqBandData.nSfb[1]; i++) { - sfb_nrg_prev[i] = fixMax(sfb_nrg_prev[i], FL2FXCONST_SGL(0.0f)); - sfb_nrg_prev[i] = fixMin(sfb_nrg_prev[i], sbr_max_energy); - } - - return (errorFlag); -} - - -/*! - \brief Verify that the noise levels are within the allowed range - - The function is equivalent to checkEnvelopeData(). - When the noise-levels are being decoded, it is already too late for - concealment. Therefore the noise levels are simply limited here. -*/ -static void -limitNoiseLevels(HANDLE_SBR_HEADER_DATA hHeaderData, /*!< Static control data */ - HANDLE_SBR_FRAME_DATA h_sbr_data) /*!< pointer to current data */ -{ - int i; - int nNfb = hHeaderData->freqBandData.nNfb; - - /* - Set range limits. The exact values depend on the coupling mode. - However this limitation is primarily intended to avoid unlimited - accumulation of the delta-coded noise levels. - */ - #define lowerLimit ((FIXP_SGL)0) /* lowerLimit actually refers to the _highest_ noise energy */ - #define upperLimit ((FIXP_SGL)35) /* upperLimit actually refers to the _lowest_ noise energy */ - - /* - Range check for current noise levels - */ - for (i = 0; i < h_sbr_data->frameInfo.nNoiseEnvelopes * nNfb; i++) { - h_sbr_data->sbrNoiseFloorLevel[i] = fixMin(h_sbr_data->sbrNoiseFloorLevel[i], upperLimit); - h_sbr_data->sbrNoiseFloorLevel[i] = fixMax(h_sbr_data->sbrNoiseFloorLevel[i], lowerLimit); - } -} - - -/*! - \brief Compensate for the wrong timing that might occur after a frame error. -*/ -static void -timeCompensateFirstEnvelope (HANDLE_SBR_HEADER_DATA hHeaderData, /*!< Static control data */ - HANDLE_SBR_FRAME_DATA h_sbr_data, /*!< pointer to actual data */ - HANDLE_SBR_PREV_FRAME_DATA h_prev_data) /*!< pointer to data of last frame */ -{ - int i, nScalefactors; - FRAME_INFO *pFrameInfo = &h_sbr_data->frameInfo; - UCHAR *nSfb = hHeaderData->freqBandData.nSfb; - int estimatedStartPos = h_prev_data->stopPos - hHeaderData->numberTimeSlots; - int refLen, newLen, shift; - FIXP_SGL deltaExp; - - /* Original length of first envelope according to bitstream */ - refLen = pFrameInfo->borders[1] - pFrameInfo->borders[0]; - /* Corrected length of first envelope (concealing can make the first envelope longer) */ - newLen = pFrameInfo->borders[1] - estimatedStartPos; - - if (newLen <= 0) { - /* An envelope length of <= 0 would not work, so we don't use it. - May occur if the previous frame was flagged bad due to a mismatch - of the old and new frame infos. */ - newLen = refLen; - estimatedStartPos = pFrameInfo->borders[0]; - } - - deltaExp = FDK_getNumOctavesDiv8(newLen, refLen); - - /* Shift by -3 to rescale ld-table, ampRes-1 to enable coarser steps */ - shift = (FRACT_BITS - 1 - ENV_EXP_FRACT - 1 + h_sbr_data->ampResolutionCurrentFrame - 3); - deltaExp = deltaExp >> shift; - pFrameInfo->borders[0] = estimatedStartPos; - pFrameInfo->bordersNoise[0] = estimatedStartPos; - - if (h_sbr_data->coupling != COUPLING_BAL) { - nScalefactors = (pFrameInfo->freqRes[0]) ? nSfb[1] : nSfb[0]; - - for (i = 0; i < nScalefactors; i++) - h_sbr_data->iEnvelope[i] = h_sbr_data->iEnvelope[i] + deltaExp; - } -} - - - -/*! - \brief Convert each envelope value from logarithmic to linear domain - - Energy levels are transmitted in powers of 2, i.e. only the exponent - is extracted from the bitstream. - Therefore, normally only integer exponents can occur. However during - fading (in case of a corrupt bitstream), a fractional part can also - occur. The data in the array iEnvelope is shifted left by ENV_EXP_FRACT - compared to an integer representation so that numbers smaller than 1 - can be represented. - - This function calculates a mantissa corresponding to the fractional - part of the exponent for each reference energy. The array iEnvelope - is converted in place to save memory. Input and output data must - be interpreted differently, as shown in the below figure: - - \image html EnvelopeData.png - - The data is then used in calculateSbrEnvelope(). -*/ -static void -requantizeEnvelopeData (HANDLE_SBR_FRAME_DATA h_sbr_data, int ampResolution) -{ - int i; - FIXP_SGL mantissa; - int ampShift = 1 - ampResolution; - int exponent; - - /* In case that ENV_EXP_FRACT is changed to something else but 0 or 8, - the initialization of this array has to be adapted! - */ -#if ENV_EXP_FRACT - static const FIXP_SGL pow2[ENV_EXP_FRACT] = - { - FL2FXCONST_SGL(0.5f * pow(2.0f, pow(0.5f, 1))), /* 0.7071 */ - FL2FXCONST_SGL(0.5f * pow(2.0f, pow(0.5f, 2))), /* 0.5946 */ - FL2FXCONST_SGL(0.5f * pow(2.0f, pow(0.5f, 3))), - FL2FXCONST_SGL(0.5f * pow(2.0f, pow(0.5f, 4))), - FL2FXCONST_SGL(0.5f * pow(2.0f, pow(0.5f, 5))), - FL2FXCONST_SGL(0.5f * pow(2.0f, pow(0.5f, 6))), - FL2FXCONST_SGL(0.5f * pow(2.0f, pow(0.5f, 7))), - FL2FXCONST_SGL(0.5f * pow(2.0f, pow(0.5f, 8))) /* 0.5013 */ - }; - - int bit, mask; -#endif - - for (i = 0; i < h_sbr_data->nScaleFactors; i++) { - exponent = (LONG)h_sbr_data->iEnvelope[i]; - -#if ENV_EXP_FRACT - - exponent = exponent >> ampShift; - mantissa = 0.5f; - - /* Amplify mantissa according to the fractional part of the - exponent (result will be between 0.500000 and 0.999999) - */ - mask = 1; /* begin with lowest bit of exponent */ - - for ( bit=ENV_EXP_FRACT-1; bit>=0; bit-- ) { - if (exponent & mask) { - /* The current bit of the exponent is set, - multiply mantissa with the corresponding factor: */ - mantissa = (FIXP_SGL)( (mantissa * pow2[bit]) << 1); - } - /* Advance to next bit */ - mask = mask << 1; - } - - /* Make integer part of exponent right aligned */ - exponent = exponent >> ENV_EXP_FRACT; - -#else - /* In case of the high amplitude resolution, 1 bit of the exponent gets lost by the shift. - This will be compensated by a mantissa of 0.5*sqrt(2) instead of 0.5 if that bit is 1. */ - mantissa = (exponent & ampShift) ? FL2FXCONST_SGL(0.707106781186548f) : FL2FXCONST_SGL(0.5f); - exponent = exponent >> ampShift; -#endif - - /* - Mantissa was set to 0.5 (instead of 1.0, therefore increase exponent by 1). - Multiply by L=nChannels=64 by increasing exponent by another 6. - => Increase exponent by 7 - */ - exponent += 7 + NRG_EXP_OFFSET; - - /* Combine mantissa and exponent and write back the result */ - h_sbr_data->iEnvelope[i] = (FIXP_SGL)(((LONG)mantissa & MASK_M) | (exponent & MASK_E)); - - } -} - - -/*! - \brief Build new reference energies from old ones and delta coded data -*/ -static void -deltaToLinearPcmEnvelopeDecoding (HANDLE_SBR_HEADER_DATA hHeaderData, /*!< Static control data */ - HANDLE_SBR_FRAME_DATA h_sbr_data, /*!< pointer to current data */ - HANDLE_SBR_PREV_FRAME_DATA h_prev_data) /*!< pointer to previous data */ -{ - int i, domain, no_of_bands, band, freqRes; - - FIXP_SGL *sfb_nrg_prev = h_prev_data->sfb_nrg_prev; - FIXP_SGL *ptr_nrg = h_sbr_data->iEnvelope; - - int offset = 2 * hHeaderData->freqBandData.nSfb[0] - hHeaderData->freqBandData.nSfb[1]; - - for (i = 0; i < h_sbr_data->frameInfo.nEnvelopes; i++) { - domain = h_sbr_data->domain_vec[i]; - freqRes = h_sbr_data->frameInfo.freqRes[i]; - - FDK_ASSERT(freqRes >= 0 && freqRes <= 1); - - no_of_bands = hHeaderData->freqBandData.nSfb[freqRes]; - - FDK_ASSERT(no_of_bands < (64)); - - if (domain == 0) - { - mapLowResEnergyVal(*ptr_nrg, sfb_nrg_prev, offset, 0, freqRes); - ptr_nrg++; - for (band = 1; band < no_of_bands; band++) - { - *ptr_nrg = *ptr_nrg + *(ptr_nrg-1); - mapLowResEnergyVal(*ptr_nrg, sfb_nrg_prev, offset, band, freqRes); - ptr_nrg++; - } - } - else - { - for (band = 0; band < no_of_bands; band++) - { - *ptr_nrg = *ptr_nrg + sfb_nrg_prev[indexLow2High(offset, band, freqRes)]; - mapLowResEnergyVal(*ptr_nrg, sfb_nrg_prev, offset, band, freqRes); - ptr_nrg++; - } - } - } -} - - -/*! - \brief Build new noise levels from old ones and delta coded data -*/ -static void -decodeNoiseFloorlevels (HANDLE_SBR_HEADER_DATA hHeaderData, /*!< Static control data */ - HANDLE_SBR_FRAME_DATA h_sbr_data, /*!< pointer to current data */ - HANDLE_SBR_PREV_FRAME_DATA h_prev_data) /*!< pointer to previous data */ -{ - int i; - int nNfb = hHeaderData->freqBandData.nNfb; - int nNoiseFloorEnvelopes = h_sbr_data->frameInfo.nNoiseEnvelopes; - - /* Decode first noise envelope */ - - if (h_sbr_data->domain_vec_noise[0] == 0) { - FIXP_SGL noiseLevel = h_sbr_data->sbrNoiseFloorLevel[0]; - for (i = 1; i < nNfb; i++) { - noiseLevel += h_sbr_data->sbrNoiseFloorLevel[i]; - h_sbr_data->sbrNoiseFloorLevel[i] = noiseLevel; - } - } - else { - for (i = 0; i < nNfb; i++) { - h_sbr_data->sbrNoiseFloorLevel[i] += h_prev_data->prevNoiseLevel[i]; - } - } - - /* If present, decode the second noise envelope - Note: nNoiseFloorEnvelopes can only be 1 or 2 */ - - if (nNoiseFloorEnvelopes > 1) { - if (h_sbr_data->domain_vec_noise[1] == 0) { - FIXP_SGL noiseLevel = h_sbr_data->sbrNoiseFloorLevel[nNfb]; - for (i = nNfb + 1; i < 2*nNfb; i++) { - noiseLevel += h_sbr_data->sbrNoiseFloorLevel[i]; - h_sbr_data->sbrNoiseFloorLevel[i] = noiseLevel; - } - } - else { - for (i = 0; i < nNfb; i++) { - h_sbr_data->sbrNoiseFloorLevel[i + nNfb] += h_sbr_data->sbrNoiseFloorLevel[i]; - } - } - } - - limitNoiseLevels(hHeaderData, h_sbr_data); - - /* Update prevNoiseLevel with the last noise envelope */ - for (i = 0; i < nNfb; i++) - h_prev_data->prevNoiseLevel[i] = h_sbr_data->sbrNoiseFloorLevel[i + nNfb*(nNoiseFloorEnvelopes-1)]; - - - /* Requantize the noise floor levels in COUPLING_OFF-mode */ - if (!h_sbr_data->coupling) { - int nf_e; - - for (i = 0; i < nNoiseFloorEnvelopes*nNfb; i++) { - nf_e = 6 - (LONG)h_sbr_data->sbrNoiseFloorLevel[i] + 1 + NOISE_EXP_OFFSET; - /* +1 to compensate for a mantissa of 0.5 instead of 1.0 */ - - h_sbr_data->sbrNoiseFloorLevel[i] = - (FIXP_SGL)( ((LONG)FL2FXCONST_SGL(0.5f)) + /* mantissa */ - (nf_e & MASK_E) ); /* exponent */ - - } - } -} |