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diff --git a/fdk-aac/libSBRdec/src/sbrdec_freq_sca.cpp b/fdk-aac/libSBRdec/src/sbrdec_freq_sca.cpp new file mode 100644 index 0000000..165f94b --- /dev/null +++ b/fdk-aac/libSBRdec/src/sbrdec_freq_sca.cpp @@ -0,0 +1,835 @@ +/* ----------------------------------------------------------------------------- +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 +----------------------------------------------------------------------------- */ + +/**************************** SBR decoder library ****************************** + + Author(s): + + Description: + +*******************************************************************************/ + +/*! + \file + \brief Frequency scale calculation +*/ + +#include "sbrdec_freq_sca.h" + +#include "transcendent.h" +#include "sbr_rom.h" +#include "env_extr.h" + +#include "genericStds.h" /* need log() for debug-code only */ + +#define MAX_OCTAVE 29 +#define MAX_SECOND_REGION 50 + +static int numberOfBands(FIXP_SGL bpo_div16, int start, int stop, int warpFlag); +static void CalcBands(UCHAR *diff, UCHAR start, UCHAR stop, UCHAR num_bands); +static SBR_ERROR modifyBands(UCHAR max_band, UCHAR *diff, UCHAR length); +static void cumSum(UCHAR start_value, UCHAR *diff, UCHAR length, + UCHAR *start_adress); + +/*! + \brief Retrieve QMF-band where the SBR range starts + + Convert startFreq which was read from the bitstream into a + QMF-channel number. + + \return Number of start band +*/ +static UCHAR getStartBand( + UINT fs, /*!< Output sampling frequency */ + UCHAR startFreq, /*!< Index to table of possible start bands */ + UINT headerDataFlags) /*!< Info to SBR mode */ +{ + INT band; + UINT fsMapped = fs; + SBR_RATE rate = DUAL; + + if (headerDataFlags & (SBRDEC_SYNTAX_USAC | SBRDEC_SYNTAX_RSVD50)) { + if (headerDataFlags & SBRDEC_QUAD_RATE) { + rate = QUAD; + } + fsMapped = sbrdec_mapToStdSampleRate(fs, 1); + } + + FDK_ASSERT(2 * (rate + 1) <= (4)); + + switch (fsMapped) { + case 192000: + band = FDK_sbrDecoder_sbr_start_freq_192[startFreq]; + break; + case 176400: + band = FDK_sbrDecoder_sbr_start_freq_176[startFreq]; + break; + case 128000: + band = FDK_sbrDecoder_sbr_start_freq_128[startFreq]; + break; + case 96000: + case 88200: + band = FDK_sbrDecoder_sbr_start_freq_88[rate][startFreq]; + break; + case 64000: + band = FDK_sbrDecoder_sbr_start_freq_64[rate][startFreq]; + break; + case 48000: + band = FDK_sbrDecoder_sbr_start_freq_48[rate][startFreq]; + break; + case 44100: + band = FDK_sbrDecoder_sbr_start_freq_44[rate][startFreq]; + break; + case 40000: + band = FDK_sbrDecoder_sbr_start_freq_40[rate][startFreq]; + break; + case 32000: + band = FDK_sbrDecoder_sbr_start_freq_32[rate][startFreq]; + break; + case 24000: + band = FDK_sbrDecoder_sbr_start_freq_24[rate][startFreq]; + break; + case 22050: + band = FDK_sbrDecoder_sbr_start_freq_22[rate][startFreq]; + break; + case 16000: + band = FDK_sbrDecoder_sbr_start_freq_16[rate][startFreq]; + break; + default: + band = 255; + } + + return band; +} + +/*! + \brief Retrieve QMF-band where the SBR range starts + + Convert startFreq which was read from the bitstream into a + QMF-channel number. + + \return Number of start band +*/ +static UCHAR getStopBand( + UINT fs, /*!< Output sampling frequency */ + UCHAR stopFreq, /*!< Index to table of possible start bands */ + UINT headerDataFlags, /*!< Info to SBR mode */ + UCHAR k0) /*!< Start freq index */ +{ + UCHAR k2; + + if (stopFreq < 14) { + INT stopMin; + INT num = 2 * (64); + UCHAR diff_tot[MAX_OCTAVE + MAX_SECOND_REGION]; + UCHAR *diff0 = diff_tot; + UCHAR *diff1 = diff_tot + MAX_OCTAVE; + + if (headerDataFlags & SBRDEC_QUAD_RATE) { + num >>= 1; + } + + if (fs < 32000) { + stopMin = (((2 * 6000 * num) / fs) + 1) >> 1; + } else { + if (fs < 64000) { + stopMin = (((2 * 8000 * num) / fs) + 1) >> 1; + } else { + stopMin = (((2 * 10000 * num) / fs) + 1) >> 1; + } + } + + /* + Choose a stop band between k1 and 64 depending on stopFreq (0..13), + based on a logarithmic scale. + The vectors diff0 and diff1 are used temporarily here. + */ + CalcBands(diff0, stopMin, 64, 13); + shellsort(diff0, 13); + cumSum(stopMin, diff0, 13, diff1); + k2 = diff1[stopFreq]; + } else if (stopFreq == 14) + k2 = 2 * k0; + else + k2 = 3 * k0; + + /* Limit to Nyquist */ + if (k2 > (64)) k2 = (64); + + /* Range checks */ + /* 1 <= difference <= 48; 1 <= fs <= 96000 */ + { + UCHAR max_freq_coeffs = (headerDataFlags & SBRDEC_QUAD_RATE) + ? MAX_FREQ_COEFFS_QUAD_RATE + : MAX_FREQ_COEFFS; + if (((k2 - k0) > max_freq_coeffs) || (k2 <= k0)) { + return 255; + } + } + + if (headerDataFlags & SBRDEC_QUAD_RATE) { + return k2; /* skip other checks: (k2 - k0) must be <= + MAX_FREQ_COEFFS_QUAD_RATE for all fs */ + } + if (headerDataFlags & (SBRDEC_SYNTAX_USAC | SBRDEC_SYNTAX_RSVD50)) { + /* 1 <= difference <= 35; 42000 <= fs <= 96000 */ + if ((fs >= 42000) && ((k2 - k0) > MAX_FREQ_COEFFS_FS44100)) { + return 255; + } + /* 1 <= difference <= 32; 46009 <= fs <= 96000 */ + if ((fs >= 46009) && ((k2 - k0) > MAX_FREQ_COEFFS_FS48000)) { + return 255; + } + } else { + /* 1 <= difference <= 35; fs == 44100 */ + if ((fs == 44100) && ((k2 - k0) > MAX_FREQ_COEFFS_FS44100)) { + return 255; + } + /* 1 <= difference <= 32; 48000 <= fs <= 96000 */ + if ((fs >= 48000) && ((k2 - k0) > MAX_FREQ_COEFFS_FS48000)) { + return 255; + } + } + + return k2; +} + +/*! + \brief Generates master frequency tables + + Frequency tables are calculated according to the selected domain + (linear/logarithmic) and granularity. + IEC 14496-3 4.6.18.3.2.1 + + \return errorCode, 0 if successful +*/ +SBR_ERROR +sbrdecUpdateFreqScale( + UCHAR *v_k_master, /*!< Master table to be created */ + UCHAR *numMaster, /*!< Number of entries in master table */ + UINT fs, /*!< SBR working sampling rate */ + HANDLE_SBR_HEADER_DATA hHeaderData, /*!< Control data from bitstream */ + UINT flags) { + FIXP_SGL bpo_div16; /* bands_per_octave divided by 16 */ + INT dk = 0; + + /* Internal variables */ + UCHAR k0, k2, i; + UCHAR num_bands0 = 0; + UCHAR num_bands1 = 0; + UCHAR diff_tot[MAX_OCTAVE + MAX_SECOND_REGION]; + UCHAR *diff0 = diff_tot; + UCHAR *diff1 = diff_tot + MAX_OCTAVE; + INT k2_achived; + INT k2_diff; + INT incr = 0; + + /* + Determine start band + */ + if (flags & SBRDEC_QUAD_RATE) { + fs >>= 1; + } + + k0 = getStartBand(fs, hHeaderData->bs_data.startFreq, flags); + if (k0 == 255) { + return SBRDEC_UNSUPPORTED_CONFIG; + } + + /* + Determine stop band + */ + k2 = getStopBand(fs, hHeaderData->bs_data.stopFreq, flags, k0); + if (k2 == 255) { + return SBRDEC_UNSUPPORTED_CONFIG; + } + + if (hHeaderData->bs_data.freqScale > 0) { /* Bark */ + INT k1; + + if (hHeaderData->bs_data.freqScale == 1) { + bpo_div16 = FL2FXCONST_SGL(12.0f / 16.0f); + } else if (hHeaderData->bs_data.freqScale == 2) { + bpo_div16 = FL2FXCONST_SGL(10.0f / 16.0f); + } else { + bpo_div16 = FL2FXCONST_SGL(8.0f / 16.0f); + } + + /* Ref: ISO/IEC 23003-3, Figure 12 - Flowchart calculation of fMaster for + * 4:1 system when bs_freq_scale > 0 */ + if (flags & SBRDEC_QUAD_RATE) { + if ((SHORT)k0 < (SHORT)(bpo_div16 >> ((FRACT_BITS - 1) - 4))) { + bpo_div16 = (FIXP_SGL)(k0 & (UCHAR)0xfe) + << ((FRACT_BITS - 1) - 4); /* bpo_div16 = floor(k0/2)*2 */ + } + } + + if (1000 * k2 > 2245 * k0) { /* Two or more regions */ + k1 = 2 * k0; + + num_bands0 = numberOfBands(bpo_div16, k0, k1, 0); + num_bands1 = + numberOfBands(bpo_div16, k1, k2, hHeaderData->bs_data.alterScale); + if (num_bands0 < 1) { + return SBRDEC_UNSUPPORTED_CONFIG; + } + if (num_bands1 < 1) { + return SBRDEC_UNSUPPORTED_CONFIG; + } + + CalcBands(diff0, k0, k1, num_bands0); + shellsort(diff0, num_bands0); + if (diff0[0] == 0) { + return SBRDEC_UNSUPPORTED_CONFIG; + } + + cumSum(k0, diff0, num_bands0, v_k_master); + + CalcBands(diff1, k1, k2, num_bands1); + shellsort(diff1, num_bands1); + if (diff0[num_bands0 - 1] > diff1[0]) { + SBR_ERROR err; + + err = modifyBands(diff0[num_bands0 - 1], diff1, num_bands1); + if (err) return SBRDEC_UNSUPPORTED_CONFIG; + } + + /* Add 2nd region */ + cumSum(k1, diff1, num_bands1, &v_k_master[num_bands0]); + *numMaster = num_bands0 + num_bands1; /* Output nr of bands */ + + } else { /* Only one region */ + k1 = k2; + + num_bands0 = numberOfBands(bpo_div16, k0, k1, 0); + if (num_bands0 < 1) { + return SBRDEC_UNSUPPORTED_CONFIG; + } + CalcBands(diff0, k0, k1, num_bands0); + shellsort(diff0, num_bands0); + if (diff0[0] == 0) { + return SBRDEC_UNSUPPORTED_CONFIG; + } + + cumSum(k0, diff0, num_bands0, v_k_master); + *numMaster = num_bands0; /* Output nr of bands */ + } + } else { /* Linear mode */ + if (hHeaderData->bs_data.alterScale == 0) { + dk = 1; + /* FLOOR to get to few number of bands (next lower even number) */ + num_bands0 = (k2 - k0) & 254; + } else { + dk = 2; + num_bands0 = (((k2 - k0) >> 1) + 1) & 254; /* ROUND to the closest fit */ + } + + if (num_bands0 < 1) { + return SBRDEC_UNSUPPORTED_CONFIG; + /* We must return already here because 'i' can become negative below. */ + } + + k2_achived = k0 + num_bands0 * dk; + k2_diff = k2 - k2_achived; + + for (i = 0; i < num_bands0; i++) diff_tot[i] = dk; + + /* If linear scale wasn't achieved */ + /* and we got too wide SBR area */ + if (k2_diff < 0) { + incr = 1; + i = 0; + } + + /* If linear scale wasn't achieved */ + /* and we got too small SBR area */ + if (k2_diff > 0) { + incr = -1; + i = num_bands0 - 1; + } + + /* Adjust diff vector to get sepc. SBR range */ + while (k2_diff != 0) { + diff_tot[i] = diff_tot[i] - incr; + i = i + incr; + k2_diff = k2_diff + incr; + } + + cumSum(k0, diff_tot, num_bands0, v_k_master); /* cumsum */ + *numMaster = num_bands0; /* Output nr of bands */ + } + + if (*numMaster < 1) { + return SBRDEC_UNSUPPORTED_CONFIG; + } + + /* Ref: ISO/IEC 23003-3 Cor.3, "In 7.5.5.2, add to the requirements:"*/ + if (flags & SBRDEC_QUAD_RATE) { + int k; + for (k = 1; k < *numMaster; k++) { + if (!(v_k_master[k] - v_k_master[k - 1] <= k0 - 2)) { + return SBRDEC_UNSUPPORTED_CONFIG; + } + } + } + + /* + Print out the calculated table + */ + + return SBRDEC_OK; +} + +/*! + \brief Calculate frequency ratio of one SBR band + + All SBR bands should span a constant frequency range in the logarithmic + domain. This function calculates the ratio of any SBR band's upper and lower + frequency. + + \return num_band-th root of k_start/k_stop +*/ +static FIXP_SGL calcFactorPerBand(int k_start, int k_stop, int num_bands) { + /* Scaled bandfactor and step 1 bit right to avoid overflow + * use double data type */ + FIXP_DBL bandfactor = FL2FXCONST_DBL(0.25f); /* Start value */ + FIXP_DBL step = FL2FXCONST_DBL(0.125f); /* Initial increment for factor */ + + int direction = 1; + + /* Because saturation can't be done in INT IIS, + * changed start and stop data type from FIXP_SGL to FIXP_DBL */ + FIXP_DBL start = k_start << (DFRACT_BITS - 8); + FIXP_DBL stop = k_stop << (DFRACT_BITS - 8); + + FIXP_DBL temp; + + int j, i = 0; + + while (step > FL2FXCONST_DBL(0.0f)) { + i++; + temp = stop; + + /* Calculate temp^num_bands: */ + for (j = 0; j < num_bands; j++) + // temp = fMult(temp,bandfactor); + temp = fMultDiv2(temp, bandfactor) << 2; + + if (temp < start) { /* Factor too strong, make it weaker */ + if (direction == 0) + /* Halfen step. Right shift is not done as fract because otherwise the + lowest bit cannot be cleared due to rounding */ + step = (FIXP_DBL)((LONG)step >> 1); + direction = 1; + bandfactor = bandfactor + step; + } else { /* Factor is too weak: make it stronger */ + if (direction == 1) step = (FIXP_DBL)((LONG)step >> 1); + direction = 0; + bandfactor = bandfactor - step; + } + + if (i > 100) { + step = FL2FXCONST_DBL(0.0f); + } + } + return FX_DBL2FX_SGL(bandfactor << 1); +} + +/*! + \brief Calculate number of SBR bands between start and stop band + + Given the number of bands per octave, this function calculates how many + bands fit in the given frequency range. + When the warpFlag is set, the 'band density' is decreased by a factor + of 1/1.3 + + \return number of bands +*/ +static int numberOfBands( + FIXP_SGL bpo_div16, /*!< Input: number of bands per octave divided by 16 */ + int start, /*!< First QMF band of SBR frequency range */ + int stop, /*!< Last QMF band of SBR frequency range + 1 */ + int warpFlag) /*!< Stretching flag */ +{ + FIXP_SGL num_bands_div128; + int num_bands; + + num_bands_div128 = + FX_DBL2FX_SGL(fMult(FDK_getNumOctavesDiv8(start, stop), bpo_div16)); + + if (warpFlag) { + /* Apply the warp factor of 1.3 to get wider bands. We use a value + of 32768/25200 instead of the exact value to avoid critical cases + of rounding. + */ + num_bands_div128 = FX_DBL2FX_SGL( + fMult(num_bands_div128, FL2FXCONST_SGL(25200.0 / 32768.0))); + } + + /* add scaled 1 for rounding to even numbers: */ + num_bands_div128 = num_bands_div128 + FL2FXCONST_SGL(1.0f / 128.0f); + /* scale back to right aligned integer and double the value: */ + num_bands = 2 * ((LONG)num_bands_div128 >> (FRACT_BITS - 7)); + + return (num_bands); +} + +/*! + \brief Calculate width of SBR bands + + Given the desired number of bands within the SBR frequency range, + this function calculates the width of each SBR band in QMF channels. + The bands get wider from start to stop (bark scale). +*/ +static void CalcBands(UCHAR *diff, /*!< Vector of widths to be calculated */ + UCHAR start, /*!< Lower end of subband range */ + UCHAR stop, /*!< Upper end of subband range */ + UCHAR num_bands) /*!< Desired number of bands */ +{ + int i; + int previous; + int current; + FIXP_SGL exact, temp; + FIXP_SGL bandfactor = calcFactorPerBand(start, stop, num_bands); + + previous = stop; /* Start with highest QMF channel */ + exact = (FIXP_SGL)( + stop << (FRACT_BITS - 8)); /* Shift left to gain some accuracy */ + + for (i = num_bands - 1; i >= 0; i--) { + /* Calculate border of next lower sbr band */ + exact = FX_DBL2FX_SGL(fMult(exact, bandfactor)); + + /* Add scaled 0.5 for rounding: + We use a value 128/256 instead of 0.5 to avoid some critical cases of + rounding. */ + temp = exact + FL2FXCONST_SGL(128.0 / 32768.0); + + /* scale back to right alinged integer: */ + current = (LONG)temp >> (FRACT_BITS - 8); + + /* Save width of band i */ + diff[i] = previous - current; + previous = current; + } +} + +/*! + \brief Calculate cumulated sum vector from delta vector +*/ +static void cumSum(UCHAR start_value, UCHAR *diff, UCHAR length, + UCHAR *start_adress) { + int i; + start_adress[0] = start_value; + for (i = 1; i <= length; i++) + start_adress[i] = start_adress[i - 1] + diff[i - 1]; +} + +/*! + \brief Adapt width of frequency bands in the second region + + If SBR spans more than 2 octaves, the upper part of a bark-frequency-scale + is calculated separately. This function tries to avoid that the second region + starts with a band smaller than the highest band of the first region. +*/ +static SBR_ERROR modifyBands(UCHAR max_band_previous, UCHAR *diff, + UCHAR length) { + int change = max_band_previous - diff[0]; + + /* Limit the change so that the last band cannot get narrower than the first + * one */ + if (change > (diff[length - 1] - diff[0]) >> 1) + change = (diff[length - 1] - diff[0]) >> 1; + + diff[0] += change; + diff[length - 1] -= change; + shellsort(diff, length); + + return SBRDEC_OK; +} + +/*! + \brief Update high resolution frequency band table +*/ +static void sbrdecUpdateHiRes(UCHAR *h_hires, UCHAR *num_hires, + UCHAR *v_k_master, UCHAR num_bands, + UCHAR xover_band) { + UCHAR i; + + *num_hires = num_bands - xover_band; + + for (i = xover_band; i <= num_bands; i++) { + h_hires[i - xover_band] = v_k_master[i]; + } +} + +/*! + \brief Build low resolution table out of high resolution table +*/ +static void sbrdecUpdateLoRes(UCHAR *h_lores, UCHAR *num_lores, UCHAR *h_hires, + UCHAR num_hires) { + UCHAR i; + + if ((num_hires & 1) == 0) { + /* If even number of hires bands */ + *num_lores = num_hires >> 1; + /* Use every second lores=hires[0,2,4...] */ + for (i = 0; i <= *num_lores; i++) h_lores[i] = h_hires[i * 2]; + } else { + /* Odd number of hires, which means xover is odd */ + *num_lores = (num_hires + 1) >> 1; + /* Use lores=hires[0,1,3,5 ...] */ + h_lores[0] = h_hires[0]; + for (i = 1; i <= *num_lores; i++) { + h_lores[i] = h_hires[i * 2 - 1]; + } + } +} + +/*! + \brief Derive a low-resolution frequency-table from the master frequency + table +*/ +void sbrdecDownSampleLoRes(UCHAR *v_result, UCHAR num_result, + UCHAR *freqBandTableRef, UCHAR num_Ref) { + int step; + int i, j; + int org_length, result_length; + int v_index[MAX_FREQ_COEFFS >> 1]; + + /* init */ + org_length = num_Ref; + result_length = num_result; + + v_index[0] = 0; /* Always use left border */ + i = 0; + while (org_length > 0) { + /* Create downsample vector */ + i++; + step = org_length / result_length; + org_length = org_length - step; + result_length--; + v_index[i] = v_index[i - 1] + step; + } + + for (j = 0; j <= i; j++) { + /* Use downsample vector to index LoResolution vector */ + v_result[j] = freqBandTableRef[v_index[j]]; + } +} + +/*! + \brief Sorting routine +*/ +void shellsort(UCHAR *in, UCHAR n) { + int i, j, v, w; + int inc = 1; + + do + inc = 3 * inc + 1; + while (inc <= n); + + do { + inc = inc / 3; + for (i = inc; i < n; i++) { + v = in[i]; + j = i; + while ((w = in[j - inc]) > v) { + in[j] = w; + j -= inc; + if (j < inc) break; + } + in[j] = v; + } + } while (inc > 1); +} + +/*! + \brief Reset frequency band tables + \return errorCode, 0 if successful +*/ +SBR_ERROR +resetFreqBandTables(HANDLE_SBR_HEADER_DATA hHeaderData, const UINT flags) { + SBR_ERROR err = SBRDEC_OK; + int k2, kx, lsb, usb; + int intTemp; + UCHAR nBandsLo, nBandsHi; + HANDLE_FREQ_BAND_DATA hFreq = &hHeaderData->freqBandData; + + /* Calculate master frequency function */ + err = sbrdecUpdateFreqScale(hFreq->v_k_master, &hFreq->numMaster, + hHeaderData->sbrProcSmplRate, hHeaderData, flags); + + if (err || (hHeaderData->bs_info.xover_band > hFreq->numMaster)) { + return SBRDEC_UNSUPPORTED_CONFIG; + } + + /* Derive Hiresolution from master frequency function */ + sbrdecUpdateHiRes(hFreq->freqBandTable[1], &nBandsHi, hFreq->v_k_master, + hFreq->numMaster, hHeaderData->bs_info.xover_band); + /* Derive Loresolution from Hiresolution */ + sbrdecUpdateLoRes(hFreq->freqBandTable[0], &nBandsLo, hFreq->freqBandTable[1], + nBandsHi); + + hFreq->nSfb[0] = nBandsLo; + hFreq->nSfb[1] = nBandsHi; + + /* Check index to freqBandTable[0] */ + if (!(nBandsLo > 0) || + (nBandsLo > (((hHeaderData->numberOfAnalysisBands == 16) + ? MAX_FREQ_COEFFS_QUAD_RATE + : MAX_FREQ_COEFFS_DUAL_RATE) >> + 1))) { + return SBRDEC_UNSUPPORTED_CONFIG; + } + + lsb = hFreq->freqBandTable[0][0]; + usb = hFreq->freqBandTable[0][nBandsLo]; + + /* Check for start frequency border k_x: + - ISO/IEC 14496-3 4.6.18.3.6 Requirements + - ISO/IEC 23003-3 7.5.5.2 Modifications and additions to the MPEG-4 SBR + tool + */ + /* Note that lsb > as hHeaderData->numberOfAnalysisBands is a valid SBR config + * for 24 band QMF analysis. */ + if ((lsb > ((flags & SBRDEC_QUAD_RATE) ? 16 : (32))) || (lsb >= usb)) { + return SBRDEC_UNSUPPORTED_CONFIG; + } + + /* Calculate number of noise bands */ + + k2 = hFreq->freqBandTable[1][nBandsHi]; + kx = hFreq->freqBandTable[1][0]; + + if (hHeaderData->bs_data.noise_bands == 0) { + hFreq->nNfb = 1; + } else /* Calculate no of noise bands 1,2 or 3 bands/octave */ + { + /* Fetch number of octaves divided by 32 */ + intTemp = (LONG)FDK_getNumOctavesDiv8(kx, k2) >> 2; + + /* Integer-Multiplication with number of bands: */ + intTemp = intTemp * hHeaderData->bs_data.noise_bands; + + /* Add scaled 0.5 for rounding: */ + intTemp = intTemp + (LONG)FL2FXCONST_SGL(0.5f / 32.0f); + + /* Convert to right-aligned integer: */ + intTemp = intTemp >> (FRACT_BITS - 1 /*sign*/ - 5 /* rescale */); + + if (intTemp == 0) intTemp = 1; + + hFreq->nNfb = intTemp; + } + + hFreq->nInvfBands = hFreq->nNfb; + + if (hFreq->nNfb > MAX_NOISE_COEFFS) { + return SBRDEC_UNSUPPORTED_CONFIG; + } + + /* Get noise bands */ + sbrdecDownSampleLoRes(hFreq->freqBandTableNoise, hFreq->nNfb, + hFreq->freqBandTable[0], nBandsLo); + + /* save old highband; required for overlap in usac + when headerchange occurs at XVAR and VARX frame; */ + hFreq->ov_highSubband = hFreq->highSubband; + + hFreq->lowSubband = lsb; + hFreq->highSubband = usb; + + return SBRDEC_OK; +} |