From 0e5af65c467b2423a0b857ae3ad98c91acc1e190 Mon Sep 17 00:00:00 2001 From: "Matthias P. Braendli" Date: Mon, 11 Nov 2019 11:38:02 +0100 Subject: Include patched FDK-AAC in the repository The initial idea was to get the DAB+ patch into upstream, but since that follows the android source releases, there is no place for a custom DAB+ patch there. So instead of having to maintain a patched fdk-aac that has to have the same .so version as the distribution package on which it is installed, we prefer having a separate fdk-aac-dab library to avoid collision. At that point, there's no reason to keep fdk-aac in a separate repository, as odr-audioenc is the only tool that needs DAB+ encoding support. Including it here simplifies installation, and makes it consistent with toolame-dab, also shipped in this repository. DAB+ decoding support (needed by ODR-SourceCompanion, dablin, etisnoop, welle.io and others) can be done using upstream FDK-AAC. --- fdk-aac/libAACenc/src/block_switch.cpp | 582 +++++++++++++++++++++++++++++++++ 1 file changed, 582 insertions(+) create mode 100644 fdk-aac/libAACenc/src/block_switch.cpp (limited to 'fdk-aac/libAACenc/src/block_switch.cpp') diff --git a/fdk-aac/libAACenc/src/block_switch.cpp b/fdk-aac/libAACenc/src/block_switch.cpp new file mode 100644 index 0000000..c132253 --- /dev/null +++ b/fdk-aac/libAACenc/src/block_switch.cpp @@ -0,0 +1,582 @@ +/* ----------------------------------------------------------------------------- +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, Tobias Chalupka + + Description: Block switching + +*******************************************************************************/ + +/****************** Includes *****************************/ + +#include "block_switch.h" +#include "genericStds.h" + +#define LOWOV_WINDOW _LOWOV_WINDOW + +/**************** internal function prototypes ***********/ + +static FIXP_DBL FDKaacEnc_GetWindowEnergy(const FIXP_DBL in[], + const INT blSwWndIdx); + +static void FDKaacEnc_CalcWindowEnergy( + BLOCK_SWITCHING_CONTROL *RESTRICT blockSwitchingControl, INT windowLen, + const INT_PCM *pTimeSignal); + +/****************** Constants *****************************/ +/* LONG START + * SHORT STOP LOWOV */ +static const INT blockType2windowShape[2][5] = { + {SINE_WINDOW, KBD_WINDOW, WRONG_WINDOW, SINE_WINDOW, KBD_WINDOW}, /* LD */ + {KBD_WINDOW, SINE_WINDOW, SINE_WINDOW, KBD_WINDOW, WRONG_WINDOW}}; /* LC */ + +/* IIR high pass coeffs */ + +#ifndef SINETABLE_16BIT + +static const FIXP_DBL hiPassCoeff[BLOCK_SWITCHING_IIR_LEN] = { + FL2FXCONST_DBL(-0.5095), FL2FXCONST_DBL(0.7548)}; + +static const FIXP_DBL accWindowNrgFac = + FL2FXCONST_DBL(0.3f); /* factor for accumulating filtered window energies */ +static const FIXP_DBL oneMinusAccWindowNrgFac = FL2FXCONST_DBL(0.7f); +/* static const float attackRatio = 10.0; */ /* lower ratio limit for attacks */ +static const FIXP_DBL invAttackRatio = + FL2FXCONST_DBL(0.1f); /* inverted lower ratio limit for attacks */ + +/* The next constants are scaled, because they are used for comparison with + * scaled values*/ +/* minimum energy for attacks */ +static const FIXP_DBL minAttackNrg = + (FL2FXCONST_DBL(1e+6f * NORM_PCM_ENERGY) >> + BLOCK_SWITCH_ENERGY_SHIFT); /* minimum energy for attacks */ + +#else + +static const FIXP_SGL hiPassCoeff[BLOCK_SWITCHING_IIR_LEN] = { + FL2FXCONST_SGL(-0.5095), FL2FXCONST_SGL(0.7548)}; + +static const FIXP_DBL accWindowNrgFac = + FL2FXCONST_DBL(0.3f); /* factor for accumulating filtered window energies */ +static const FIXP_SGL oneMinusAccWindowNrgFac = FL2FXCONST_SGL(0.7f); +/* static const float attackRatio = 10.0; */ /* lower ratio limit for attacks */ +static const FIXP_SGL invAttackRatio = + FL2FXCONST_SGL(0.1f); /* inverted lower ratio limit for attacks */ +/* minimum energy for attacks */ +static const FIXP_DBL minAttackNrg = + (FL2FXCONST_DBL(1e+6f * NORM_PCM_ENERGY) >> + BLOCK_SWITCH_ENERGY_SHIFT); /* minimum energy for attacks */ + +#endif + +/**************** internal function prototypes ***********/ + +/****************** Routines ****************************/ +void FDKaacEnc_InitBlockSwitching( + BLOCK_SWITCHING_CONTROL *blockSwitchingControl, INT isLowDelay) { + FDKmemclear(blockSwitchingControl, sizeof(BLOCK_SWITCHING_CONTROL)); + + if (isLowDelay) { + blockSwitchingControl->nBlockSwitchWindows = 4; + blockSwitchingControl->allowShortFrames = 0; + blockSwitchingControl->allowLookAhead = 0; + } else { + blockSwitchingControl->nBlockSwitchWindows = 8; + blockSwitchingControl->allowShortFrames = 1; + blockSwitchingControl->allowLookAhead = 1; + } + + blockSwitchingControl->noOfGroups = MAX_NO_OF_GROUPS; + + /* Initialize startvalue for blocktype */ + blockSwitchingControl->lastWindowSequence = LONG_WINDOW; + blockSwitchingControl->windowShape = + blockType2windowShape[blockSwitchingControl->allowShortFrames] + [blockSwitchingControl->lastWindowSequence]; +} + +static const INT suggestedGroupingTable[TRANS_FAC][MAX_NO_OF_GROUPS] = { + /* Attack in Window 0 */ {1, 3, 3, 1}, + /* Attack in Window 1 */ {1, 1, 3, 3}, + /* Attack in Window 2 */ {2, 1, 3, 2}, + /* Attack in Window 3 */ {3, 1, 3, 1}, + /* Attack in Window 4 */ {3, 1, 1, 3}, + /* Attack in Window 5 */ {3, 2, 1, 2}, + /* Attack in Window 6 */ {3, 3, 1, 1}, + /* Attack in Window 7 */ {3, 3, 1, 1}}; + +/* change block type depending on current blocktype and whether there's an + * attack */ +/* assume no look-ahead */ +static const INT chgWndSq[2][N_BLOCKTYPES] = { + /* LONG WINDOW START_WINDOW SHORT_WINDOW STOP_WINDOW, + LOWOV_WINDOW, WRONG_WINDOW */ + /*no attack*/ {LONG_WINDOW, STOP_WINDOW, WRONG_WINDOW, LONG_WINDOW, + STOP_WINDOW, WRONG_WINDOW}, + /*attack */ {START_WINDOW, LOWOV_WINDOW, WRONG_WINDOW, START_WINDOW, + LOWOV_WINDOW, WRONG_WINDOW}}; + +/* change block type depending on current blocktype and whether there's an + * attack */ +/* assume look-ahead */ +static const INT chgWndSqLkAhd[2][2][N_BLOCKTYPES] = { + /*attack LONG WINDOW START_WINDOW SHORT_WINDOW STOP_WINDOW LOWOV_WINDOW, WRONG_WINDOW */ /* last attack */ + /*no attack*/ { + {LONG_WINDOW, SHORT_WINDOW, STOP_WINDOW, LONG_WINDOW, WRONG_WINDOW, + WRONG_WINDOW}, /* no attack */ + /*attack */ {START_WINDOW, SHORT_WINDOW, SHORT_WINDOW, START_WINDOW, + WRONG_WINDOW, WRONG_WINDOW}}, /* no attack */ + /*no attack*/ {{LONG_WINDOW, SHORT_WINDOW, SHORT_WINDOW, LONG_WINDOW, + WRONG_WINDOW, WRONG_WINDOW}, /* attack */ + /*attack */ {START_WINDOW, SHORT_WINDOW, SHORT_WINDOW, + START_WINDOW, WRONG_WINDOW, + WRONG_WINDOW}} /* attack */ +}; + +int FDKaacEnc_BlockSwitching(BLOCK_SWITCHING_CONTROL *blockSwitchingControl, + const INT granuleLength, const int isLFE, + const INT_PCM *pTimeSignal) { + UINT i; + FIXP_DBL enM1, enMax; + + UINT nBlockSwitchWindows = blockSwitchingControl->nBlockSwitchWindows; + + /* for LFE : only LONG window allowed */ + if (isLFE) { + /* case LFE: */ + /* only long blocks, always use sine windows (MPEG2 AAC, MPEG4 AAC) */ + blockSwitchingControl->lastWindowSequence = LONG_WINDOW; + blockSwitchingControl->windowShape = SINE_WINDOW; + blockSwitchingControl->noOfGroups = 1; + blockSwitchingControl->groupLen[0] = 1; + + return (0); + }; + + /* Save current attack index as last attack index */ + blockSwitchingControl->lastattack = blockSwitchingControl->attack; + blockSwitchingControl->lastAttackIndex = blockSwitchingControl->attackIndex; + + /* Save current window energy as last window energy */ + FDKmemcpy(blockSwitchingControl->windowNrg[0], + blockSwitchingControl->windowNrg[1], + sizeof(blockSwitchingControl->windowNrg[0])); + FDKmemcpy(blockSwitchingControl->windowNrgF[0], + blockSwitchingControl->windowNrgF[1], + sizeof(blockSwitchingControl->windowNrgF[0])); + + if (blockSwitchingControl->allowShortFrames) { + /* Calculate suggested grouping info for the last frame */ + + /* Reset grouping info */ + FDKmemclear(blockSwitchingControl->groupLen, + sizeof(blockSwitchingControl->groupLen)); + + /* Set grouping info */ + blockSwitchingControl->noOfGroups = MAX_NO_OF_GROUPS; + + FDKmemcpy(blockSwitchingControl->groupLen, + suggestedGroupingTable[blockSwitchingControl->lastAttackIndex], + sizeof(blockSwitchingControl->groupLen)); + + if (blockSwitchingControl->attack == TRUE) + blockSwitchingControl->maxWindowNrg = + FDKaacEnc_GetWindowEnergy(blockSwitchingControl->windowNrg[0], + blockSwitchingControl->lastAttackIndex); + else + blockSwitchingControl->maxWindowNrg = FL2FXCONST_DBL(0.0); + } + + /* Calculate unfiltered and filtered energies in subwindows and combine to + * segments */ + FDKaacEnc_CalcWindowEnergy( + blockSwitchingControl, + granuleLength >> (nBlockSwitchWindows == 4 ? 2 : 3), pTimeSignal); + + /* now calculate if there is an attack */ + + /* reset attack */ + blockSwitchingControl->attack = FALSE; + + /* look for attack */ + enMax = FL2FXCONST_DBL(0.0f); + enM1 = blockSwitchingControl->windowNrgF[0][nBlockSwitchWindows - 1]; + + for (i = 0; i < nBlockSwitchWindows; i++) { + FIXP_DBL tmp = + fMultDiv2(oneMinusAccWindowNrgFac, blockSwitchingControl->accWindowNrg); + blockSwitchingControl->accWindowNrg = fMultAdd(tmp, accWindowNrgFac, enM1); + + if (fMult(blockSwitchingControl->windowNrgF[1][i], invAttackRatio) > + blockSwitchingControl->accWindowNrg) { + blockSwitchingControl->attack = TRUE; + blockSwitchingControl->attackIndex = i; + } + enM1 = blockSwitchingControl->windowNrgF[1][i]; + enMax = fixMax(enMax, enM1); + } + + if (enMax < minAttackNrg) blockSwitchingControl->attack = FALSE; + + /* Check if attack spreads over frame border */ + if ((blockSwitchingControl->attack == FALSE) && + (blockSwitchingControl->lastattack == TRUE)) { + /* if attack is in last window repeat SHORT_WINDOW */ + if (((blockSwitchingControl->windowNrgF[0][nBlockSwitchWindows - 1] >> 4) > + fMult((FIXP_DBL)(10 << (DFRACT_BITS - 1 - 4)), + blockSwitchingControl->windowNrgF[1][1])) && + (blockSwitchingControl->lastAttackIndex == + (INT)nBlockSwitchWindows - 1)) { + blockSwitchingControl->attack = TRUE; + blockSwitchingControl->attackIndex = 0; + } + } + + if (blockSwitchingControl->allowLookAhead) { + blockSwitchingControl->lastWindowSequence = + chgWndSqLkAhd[blockSwitchingControl->lastattack] + [blockSwitchingControl->attack] + [blockSwitchingControl->lastWindowSequence]; + } else { + /* Low Delay */ + blockSwitchingControl->lastWindowSequence = + chgWndSq[blockSwitchingControl->attack] + [blockSwitchingControl->lastWindowSequence]; + } + + /* update window shape */ + blockSwitchingControl->windowShape = + blockType2windowShape[blockSwitchingControl->allowShortFrames] + [blockSwitchingControl->lastWindowSequence]; + + return (0); +} + +static FIXP_DBL FDKaacEnc_GetWindowEnergy(const FIXP_DBL in[], + const INT blSwWndIdx) { + /* For coherency, change FDKaacEnc_GetWindowEnergy() to calcluate the energy + for a block switching analysis windows, not for a short block. The same is + done FDKaacEnc_CalcWindowEnergy(). The result of + FDKaacEnc_GetWindowEnergy() is used for a comparision of the max energy of + left/right channel. */ + + return in[blSwWndIdx]; +} + +static void FDKaacEnc_CalcWindowEnergy( + BLOCK_SWITCHING_CONTROL *RESTRICT blockSwitchingControl, INT windowLen, + const INT_PCM *pTimeSignal) { + INT i; + UINT w; + +#ifndef SINETABLE_16BIT + const FIXP_DBL hiPassCoeff0 = hiPassCoeff[0]; + const FIXP_DBL hiPassCoeff1 = hiPassCoeff[1]; +#else + const FIXP_SGL hiPassCoeff0 = hiPassCoeff[0]; + const FIXP_SGL hiPassCoeff1 = hiPassCoeff[1]; +#endif + + FIXP_DBL temp_iirState0 = blockSwitchingControl->iirStates[0]; + FIXP_DBL temp_iirState1 = blockSwitchingControl->iirStates[1]; + + /* sum up scalarproduct of timesignal as windowed Energies */ + for (w = 0; w < blockSwitchingControl->nBlockSwitchWindows; w++) { + ULONG temp_windowNrg = 0x0; + ULONG temp_windowNrgF = 0x0; + + /* windowNrg = sum(timesample^2) */ + for (i = 0; i < windowLen; i++) { + FIXP_DBL tempUnfiltered, t1, t2; + /* tempUnfiltered is scaled with 1 to prevent overflows during calculation + * of tempFiltred */ +#if SAMPLE_BITS == DFRACT_BITS + tempUnfiltered = (FIXP_DBL)*pTimeSignal++ >> 1; +#else + tempUnfiltered = (FIXP_DBL)*pTimeSignal++ + << (DFRACT_BITS - SAMPLE_BITS - 1); +#endif + t1 = fMultDiv2(hiPassCoeff1, tempUnfiltered - temp_iirState0); + t2 = fMultDiv2(hiPassCoeff0, temp_iirState1); + temp_iirState0 = tempUnfiltered; + temp_iirState1 = (t1 - t2) << 1; + + temp_windowNrg += (LONG)fPow2Div2(temp_iirState0) >> + (BLOCK_SWITCH_ENERGY_SHIFT - 1 - 2); + temp_windowNrgF += (LONG)fPow2Div2(temp_iirState1) >> + (BLOCK_SWITCH_ENERGY_SHIFT - 1 - 2); + } + blockSwitchingControl->windowNrg[1][w] = + (LONG)fMin(temp_windowNrg, (UINT)MAXVAL_DBL); + blockSwitchingControl->windowNrgF[1][w] = + (LONG)fMin(temp_windowNrgF, (UINT)MAXVAL_DBL); + } + blockSwitchingControl->iirStates[0] = temp_iirState0; + blockSwitchingControl->iirStates[1] = temp_iirState1; +} + +static const UCHAR synchronizedBlockTypeTable[5][5] = { + /* LONG_WINDOW START_WINDOW SHORT_WINDOW STOP_WINDOW + LOWOV_WINDOW*/ + /* LONG_WINDOW */ {LONG_WINDOW, START_WINDOW, SHORT_WINDOW, STOP_WINDOW, + LOWOV_WINDOW}, + /* START_WINDOW */ + {START_WINDOW, START_WINDOW, SHORT_WINDOW, SHORT_WINDOW, LOWOV_WINDOW}, + /* SHORT_WINDOW */ + {SHORT_WINDOW, SHORT_WINDOW, SHORT_WINDOW, SHORT_WINDOW, WRONG_WINDOW}, + /* STOP_WINDOW */ + {STOP_WINDOW, SHORT_WINDOW, SHORT_WINDOW, STOP_WINDOW, LOWOV_WINDOW}, + /* LOWOV_WINDOW */ + {LOWOV_WINDOW, LOWOV_WINDOW, WRONG_WINDOW, LOWOV_WINDOW, LOWOV_WINDOW}, +}; + +int FDKaacEnc_SyncBlockSwitching( + BLOCK_SWITCHING_CONTROL *blockSwitchingControlLeft, + BLOCK_SWITCHING_CONTROL *blockSwitchingControlRight, const INT nChannels, + const INT commonWindow) { + UCHAR patchType = LONG_WINDOW; + + if (nChannels == 2 && commonWindow == TRUE) { + /* could be better with a channel loop (need a handle to psy_data) */ + /* get suggested Block Types and synchronize */ + patchType = synchronizedBlockTypeTable[patchType][blockSwitchingControlLeft + ->lastWindowSequence]; + patchType = synchronizedBlockTypeTable[patchType][blockSwitchingControlRight + ->lastWindowSequence]; + + /* sanity check (no change from low overlap window to short winow and vice + * versa) */ + if (patchType == WRONG_WINDOW) return -1; /* mixed up AAC-LC and AAC-LD */ + + /* Set synchronized Blocktype */ + blockSwitchingControlLeft->lastWindowSequence = patchType; + blockSwitchingControlRight->lastWindowSequence = patchType; + + /* update window shape */ + blockSwitchingControlLeft->windowShape = + blockType2windowShape[blockSwitchingControlLeft->allowShortFrames] + [blockSwitchingControlLeft->lastWindowSequence]; + blockSwitchingControlRight->windowShape = + blockType2windowShape[blockSwitchingControlLeft->allowShortFrames] + [blockSwitchingControlRight->lastWindowSequence]; + } + + if (blockSwitchingControlLeft->allowShortFrames) { + int i; + + if (nChannels == 2) { + if (commonWindow == TRUE) { + /* Synchronize grouping info */ + int windowSequenceLeftOld = + blockSwitchingControlLeft->lastWindowSequence; + int windowSequenceRightOld = + blockSwitchingControlRight->lastWindowSequence; + + /* Long Blocks */ + if (patchType != SHORT_WINDOW) { + /* Set grouping info */ + blockSwitchingControlLeft->noOfGroups = 1; + blockSwitchingControlRight->noOfGroups = 1; + blockSwitchingControlLeft->groupLen[0] = 1; + blockSwitchingControlRight->groupLen[0] = 1; + + for (i = 1; i < MAX_NO_OF_GROUPS; i++) { + blockSwitchingControlLeft->groupLen[i] = 0; + blockSwitchingControlRight->groupLen[i] = 0; + } + } + + /* Short Blocks */ + else { + /* in case all two channels were detected as short-blocks before + * syncing, use the grouping of channel with higher maxWindowNrg */ + if ((windowSequenceLeftOld == SHORT_WINDOW) && + (windowSequenceRightOld == SHORT_WINDOW)) { + if (blockSwitchingControlLeft->maxWindowNrg > + blockSwitchingControlRight->maxWindowNrg) { + /* Left Channel wins */ + blockSwitchingControlRight->noOfGroups = + blockSwitchingControlLeft->noOfGroups; + for (i = 0; i < MAX_NO_OF_GROUPS; i++) { + blockSwitchingControlRight->groupLen[i] = + blockSwitchingControlLeft->groupLen[i]; + } + } else { + /* Right Channel wins */ + blockSwitchingControlLeft->noOfGroups = + blockSwitchingControlRight->noOfGroups; + for (i = 0; i < MAX_NO_OF_GROUPS; i++) { + blockSwitchingControlLeft->groupLen[i] = + blockSwitchingControlRight->groupLen[i]; + } + } + } else if ((windowSequenceLeftOld == SHORT_WINDOW) && + (windowSequenceRightOld != SHORT_WINDOW)) { + /* else use grouping of short-block channel */ + blockSwitchingControlRight->noOfGroups = + blockSwitchingControlLeft->noOfGroups; + for (i = 0; i < MAX_NO_OF_GROUPS; i++) { + blockSwitchingControlRight->groupLen[i] = + blockSwitchingControlLeft->groupLen[i]; + } + } else if ((windowSequenceRightOld == SHORT_WINDOW) && + (windowSequenceLeftOld != SHORT_WINDOW)) { + blockSwitchingControlLeft->noOfGroups = + blockSwitchingControlRight->noOfGroups; + for (i = 0; i < MAX_NO_OF_GROUPS; i++) { + blockSwitchingControlLeft->groupLen[i] = + blockSwitchingControlRight->groupLen[i]; + } + } else { + /* syncing a start and stop window ... */ + blockSwitchingControlLeft->noOfGroups = + blockSwitchingControlRight->noOfGroups = 2; + blockSwitchingControlLeft->groupLen[0] = + blockSwitchingControlRight->groupLen[0] = 4; + blockSwitchingControlLeft->groupLen[1] = + blockSwitchingControlRight->groupLen[1] = 4; + } + } /* Short Blocks */ + } else { + /* stereo, no common window */ + if (blockSwitchingControlLeft->lastWindowSequence != SHORT_WINDOW) { + blockSwitchingControlLeft->noOfGroups = 1; + blockSwitchingControlLeft->groupLen[0] = 1; + for (i = 1; i < MAX_NO_OF_GROUPS; i++) { + blockSwitchingControlLeft->groupLen[i] = 0; + } + } + if (blockSwitchingControlRight->lastWindowSequence != SHORT_WINDOW) { + blockSwitchingControlRight->noOfGroups = 1; + blockSwitchingControlRight->groupLen[0] = 1; + for (i = 1; i < MAX_NO_OF_GROUPS; i++) { + blockSwitchingControlRight->groupLen[i] = 0; + } + } + } /* common window */ + } else { + /* Mono */ + if (blockSwitchingControlLeft->lastWindowSequence != SHORT_WINDOW) { + blockSwitchingControlLeft->noOfGroups = 1; + blockSwitchingControlLeft->groupLen[0] = 1; + + for (i = 1; i < MAX_NO_OF_GROUPS; i++) { + blockSwitchingControlLeft->groupLen[i] = 0; + } + } + } + } /* allowShortFrames */ + + /* Translate LOWOV_WINDOW block type to a meaningful window shape. */ + if (!blockSwitchingControlLeft->allowShortFrames) { + if (blockSwitchingControlLeft->lastWindowSequence != LONG_WINDOW && + blockSwitchingControlLeft->lastWindowSequence != STOP_WINDOW) { + blockSwitchingControlLeft->lastWindowSequence = LONG_WINDOW; + blockSwitchingControlLeft->windowShape = LOL_WINDOW; + } + } + if (nChannels == 2) { + if (!blockSwitchingControlRight->allowShortFrames) { + if (blockSwitchingControlRight->lastWindowSequence != LONG_WINDOW && + blockSwitchingControlRight->lastWindowSequence != STOP_WINDOW) { + blockSwitchingControlRight->lastWindowSequence = LONG_WINDOW; + blockSwitchingControlRight->windowShape = LOL_WINDOW; + } + } + } + + return 0; +} -- cgit v1.2.3