/* ------------------------------------------------------------------ * Copyright (C) 1998-2009 PacketVideo * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either * express or implied. * See the License for the specific language governing permissions * and limitations under the License. * ------------------------------------------------------------------- */ /* Filename: ps_all_pass_fract_delay_filter.c ------------------------------------------------------------------------------ REVISION HISTORY Who: Date: MM/DD/YYYY Description: ------------------------------------------------------------------------------ INPUT AND OUTPUT DEFINITIONS ------------------------------------------------------------------------------ FUNCTION DESCRIPTION Decorrelation Decorrelation is achieved by means of all-pass filtering and delaying Sub-band samples s_k(n) are converted into de-correlated sub-bands samples d_k(n). k index for frequency, n time index _______ ________ | | _______ | | ->|Hybrid | LF ---- | |->| Hybrid |--> | Anal. | | | | | Synth | QMF -> L ------- o----------------------->| | -------- Synth QMF | s_k(n) |Stereo |--------------> Anal. -------------------------->| | _______ | | | | ________ | | HF --o | ----------- |Process| | | ->| Delay | | ->| |-------->| |->| Hybrid |--> ------- | |decorrelate| d_k(n) | | | Synth | QMF -> R ---->| |-------->| | -------- Synth ----------- |_______|--------------> Delay is introduced to compensate QMF bands not passed through Hybrid Analysis ------------------------------------------------------------------------------ REQUIREMENTS ------------------------------------------------------------------------------ REFERENCES SC 29 Software Copyright Licencing Disclaimer: This software module was originally developed by Coding Technologies and edited by - in the course of development of the ISO/IEC 13818-7 and ISO/IEC 14496-3 standards for reference purposes and its performance may not have been optimized. This software module is an implementation of one or more tools as specified by the ISO/IEC 13818-7 and ISO/IEC 14496-3 standards. ISO/IEC gives users free license to this software module or modifications thereof for use in products claiming conformance to audiovisual and image-coding related ITU Recommendations and/or ISO/IEC International Standards. ISO/IEC gives users the same free license to this software module or modifications thereof for research purposes and further ISO/IEC standardisation. Those intending to use this software module in products are advised that its use may infringe existing patents. ISO/IEC have no liability for use of this software module or modifications thereof. Copyright is not released for products that do not conform to audiovisual and image-coding related ITU Recommendations and/or ISO/IEC International Standards. The original developer retains full right to modify and use the code for its own purpose, assign or donate the code to a third party and to inhibit third parties from using the code for products that do not conform to audiovisual and image-coding related ITU Recommendations and/or ISO/IEC International Standards. This copyright notice must be included in all copies or derivative works. Copyright (c) ISO/IEC 2003. ------------------------------------------------------------------------------ PSEUDO-CODE ------------------------------------------------------------------------------ */ /*---------------------------------------------------------------------------- ; INCLUDES ----------------------------------------------------------------------------*/ #ifdef AAC_PLUS #ifdef PARAMETRICSTEREO #include "pv_audio_type_defs.h" #include "ps_decorrelate.h" #include "aac_mem_funcs.h" #include "ps_all_pass_filter_coeff.h" #include "ps_pwr_transient_detection.h" #include "ps_all_pass_fract_delay_filter.h" #include "fxp_mul32.h" /*---------------------------------------------------------------------------- ; MACROS ; Define module specific macros here ----------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------- ; DEFINES ; Include all pre-processor statements here. Include conditional ; compile variables also. ----------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------- ; LOCAL FUNCTION DEFINITIONS ; Function Prototype declaration ----------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------- ; LOCAL STORE/BUFFER/POINTER DEFINITIONS ; Variable declaration - defined here and used outside this module ----------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------- ; EXTERNAL FUNCTION REFERENCES ; Declare functions defined elsewhere and referenced in this module ----------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------- ; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES ; Declare variables used in this module but defined elsewhere ----------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------- ; FUNCTION CODE ----------------------------------------------------------------------------*/ /* * For lower subbands * Apply all-pass filtering * */ void ps_all_pass_fract_delay_filter_type_I(UInt32 *delayBufIndex, Int32 sb_delay, const Int32 *ppFractDelayPhaseFactorSer, Int32 ***pppRealDelayRBufferSer, Int32 ***pppImagDelayRBufferSer, Int32 *rIn, Int32 *iIn) { Int32 cmplx; Int16 rTmp0; Int32 rTmp; Int32 iTmp; Int32 *pt_rTmp; Int32 *pt_iTmp; /* * All pass filters * 2 * ___ Q_fract(k,m)*z^(-d(m)) - a(m)*g_decay_slope(k) * z^(-2)*phi_fract(k)* | | ------------------------------------------------ * m=0 1 - a(m)*g_decay_slope(k)*Q_fract(k,m)*z^(-d(m)) * * * Fractional delay matrix: * * Q_fract(k,m) = exp(-j*pi*q(m)*f_center(k)) 0<= k <= SUBQMF_GROUPS * * Vectors: a(m), q(m), d(m) are constants * * m m 0 1 2 * ------------------------------- * delay length d(m) == 3 4 5 (Fs > 32 KHz) * fractional delay length q(m) == 0.43 0.75 0.347 * filter coefficient a(m) == 0.65144 0.56472 0.48954 * * g_decay_slope(k) is given */ Int32 tmp_r; Int32 tmp_i; pt_rTmp = &pppRealDelayRBufferSer[0][*(delayBufIndex)][sb_delay]; pt_iTmp = &pppImagDelayRBufferSer[0][*(delayBufIndex++)][sb_delay]; cmplx = *(ppFractDelayPhaseFactorSer++); /* Q_fract(k,m) */ tmp_r = *pt_rTmp << 1; tmp_i = *pt_iTmp << 1; rTmp = cmplx_mul32_by_16(tmp_r, -tmp_i, cmplx); rTmp0 = Qfmt15(0.65143905753106f); iTmp = cmplx_mul32_by_16(tmp_i, tmp_r, cmplx); iTmp = fxp_mac32_by_16(-*iIn << 1, rTmp0, iTmp); /* Q_fract(k,m)*y(n-1) - a(m)*g_decay_slope(k)*x(n) */ *pt_iTmp = fxp_mac32_by_16(iTmp << 1, rTmp0, *iIn); /* y(n) = x(n) + a(m)*g_decay_slope(k)*( Q_fract(k,m)*y(n-1) - a(m)*g_decay_slope(k)*x(n)) */ *iIn = iTmp; rTmp = fxp_mac32_by_16(-*rIn << 1, rTmp0, rTmp); *pt_rTmp = fxp_mac32_by_16(rTmp << 1, rTmp0, *rIn); *rIn = rTmp; pt_rTmp = &pppRealDelayRBufferSer[1][*(delayBufIndex)][sb_delay]; pt_iTmp = &pppImagDelayRBufferSer[1][*(delayBufIndex++)][sb_delay]; cmplx = *(ppFractDelayPhaseFactorSer++); /* Q_fract(k,m) */ tmp_r = *pt_rTmp << 1; tmp_i = *pt_iTmp << 1; rTmp = cmplx_mul32_by_16(tmp_r, -tmp_i, cmplx); rTmp0 = Qfmt15(0.56471812200776f); iTmp = cmplx_mul32_by_16(tmp_i, tmp_r, cmplx); iTmp = fxp_mac32_by_16(-*iIn << 1, rTmp0, iTmp); /* Q_fract(k,m)*y(n-1) - a(m)*g_decay_slope(k)*x(n) */ *pt_iTmp = fxp_mac32_by_16(iTmp << 1, rTmp0, *iIn); /* y(n) = x(n) + a(m)*g_decay_slope(k)*( Q_fract(k,m)*y(n-1) - a(m)*g_decay_slope(k)*x(n)) */ *iIn = iTmp; rTmp = fxp_mac32_by_16(-*rIn << 1, rTmp0, rTmp); *pt_rTmp = fxp_mac32_by_16(rTmp << 1, rTmp0, *rIn); *rIn = rTmp; pt_rTmp = &pppRealDelayRBufferSer[2][*(delayBufIndex)][sb_delay]; pt_iTmp = &pppImagDelayRBufferSer[2][*(delayBufIndex)][sb_delay]; cmplx = *(ppFractDelayPhaseFactorSer); /* Q_fract(k,m) */ tmp_r = *pt_rTmp << 1; tmp_i = *pt_iTmp << 1; rTmp = cmplx_mul32_by_16(tmp_r, -tmp_i, cmplx); rTmp0 = Qfmt15(0.97908331911390f); iTmp = cmplx_mul32_by_16(tmp_i, tmp_r, cmplx); iTmp = fxp_mac32_by_16(-*iIn, rTmp0, iTmp); /* Q_fract(k,m)*y(n-1) - a(m)*g_decay_slope(k)*x(n) */ *pt_iTmp = fxp_mac32_by_16(iTmp, rTmp0, *iIn); /* y(n) = x(n) + a(m)*g_decay_slope(k)*( Q_fract(k,m)*y(n-1) - a(m)*g_decay_slope(k)*x(n)) */ *iIn = iTmp << 2; rTmp = fxp_mac32_by_16(-*rIn, rTmp0, rTmp); *pt_rTmp = fxp_mac32_by_16(rTmp, rTmp0, *rIn); *rIn = rTmp << 2; } void ps_all_pass_fract_delay_filter_type_II(UInt32 *delayBufIndex, Int32 sb_delay, const Int32 *ppFractDelayPhaseFactorSer, Int32 ***pppRealDelayRBufferSer, Int32 ***pppImagDelayRBufferSer, Int32 *rIn, Int32 *iIn, Int32 decayScaleFactor) { Int32 cmplx; Int16 rTmp0; Int32 rTmp; Int32 iTmp; Int32 *pt_rTmp; Int32 *pt_iTmp; const Int16 *pt_delay; /* * All pass filters * 2 * ___ Q_fract(k,m)*z^(-d(m)) - a(m)*g_decay_slope(k) * z^(-2)*phi_fract(k)* | | ------------------------------------------------ * m=0 1 - a(m)*g_decay_slope(k)*Q_fract(k,m)*z^(-d(m)) * * * Fractional delay matrix: * * Q_fract(k,m) = exp(-j*pi*q(m)*f_center(k)) 0<= k <= SUBQMF_GROUPS * * Vectors: a(m), q(m), d(m) are constants * * m m 0 1 2 * ------------------------------- * delay length d(m) == 3 4 5 (Fs > 32 KHz) * fractional delay length q(m) == 0.43 0.75 0.347 * filter coefficient a(m) == 0.65144 0.56472 0.48954 * * g_decay_slope(k) is given */ Int32 tmp_r; Int32 tmp_i; pt_rTmp = &pppRealDelayRBufferSer[0][*(delayBufIndex)][sb_delay]; pt_iTmp = &pppImagDelayRBufferSer[0][*(delayBufIndex++)][sb_delay]; cmplx = *(ppFractDelayPhaseFactorSer++); /* Q_fract(k,m) */ pt_delay = aRevLinkDecaySerCoeff[decayScaleFactor]; tmp_r = *pt_rTmp << 1; tmp_i = *pt_iTmp << 1; rTmp = cmplx_mul32_by_16(tmp_r, -tmp_i, cmplx); rTmp0 = *(pt_delay++); iTmp = cmplx_mul32_by_16(tmp_i, tmp_r, cmplx); iTmp = fxp_mac32_by_16(-*iIn << 1, rTmp0, iTmp); /* Q_fract(k,m)*y(n-1) - a(m)*g_decay_slope(k)*x(n) */ *pt_iTmp = fxp_mac32_by_16(iTmp << 1, rTmp0, *iIn); /* y(n) = x(n) + a(m)*g_decay_slope(k)*( Q_fract(k,m)*y(n-1) - a(m)*g_decay_slope(k)*x(n)) */ *iIn = iTmp; rTmp = fxp_mac32_by_16(-*rIn << 1, rTmp0, rTmp); *pt_rTmp = fxp_mac32_by_16(rTmp << 1, rTmp0, *rIn); *rIn = rTmp; pt_rTmp = &pppRealDelayRBufferSer[1][*(delayBufIndex)][sb_delay]; pt_iTmp = &pppImagDelayRBufferSer[1][*(delayBufIndex++)][sb_delay]; cmplx = *(ppFractDelayPhaseFactorSer++); /* Q_fract(k,m) */ tmp_r = *pt_rTmp << 1; tmp_i = *pt_iTmp << 1; rTmp = cmplx_mul32_by_16(tmp_r, -tmp_i, cmplx); rTmp0 = *(pt_delay++); iTmp = cmplx_mul32_by_16(tmp_i, tmp_r, cmplx); iTmp = fxp_mac32_by_16(-*iIn << 1, rTmp0, iTmp); /* Q_fract(k,m)*y(n-1) - a(m)*g_decay_slope(k)*x(n) */ *pt_iTmp = fxp_mac32_by_16(iTmp << 1, rTmp0, *iIn); /* y(n) = x(n) + a(m)*g_decay_slope(k)*( Q_fract(k,m)*y(n-1) - a(m)*g_decay_slope(k)*x(n)) */ *iIn = iTmp; rTmp = fxp_mac32_by_16(-*rIn << 1, rTmp0, rTmp); *pt_rTmp = fxp_mac32_by_16(rTmp << 1, rTmp0, *rIn); *rIn = rTmp; pt_rTmp = &pppRealDelayRBufferSer[2][*(delayBufIndex)][sb_delay]; pt_iTmp = &pppImagDelayRBufferSer[2][*(delayBufIndex)][sb_delay]; cmplx = *(ppFractDelayPhaseFactorSer); /* Q_fract(k,m) */ tmp_r = *pt_rTmp << 1; tmp_i = *pt_iTmp << 1; rTmp = cmplx_mul32_by_16(tmp_r, -tmp_i, cmplx); rTmp0 = *(pt_delay); iTmp = cmplx_mul32_by_16(tmp_i, tmp_r, cmplx); iTmp = fxp_mac32_by_16(-*iIn, rTmp0, iTmp); /* Q_fract(k,m)*y(n-1) - a(m)*g_decay_slope(k)*x(n) */ *pt_iTmp = fxp_mac32_by_16(iTmp, rTmp0, *iIn); /* y(n) = x(n) + a(m)*g_decay_slope(k)*( Q_fract(k,m)*y(n-1) - a(m)*g_decay_slope(k)*x(n)) */ *iIn = iTmp << 2; rTmp = fxp_mac32_by_16(-*rIn, rTmp0, rTmp); *pt_rTmp = fxp_mac32_by_16(rTmp, rTmp0, *rIn); *rIn = rTmp << 2; } #endif #endif