| /* ------------------------------------------------------------------ |
| * 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. |
| * ------------------------------------------------------------------- |
| */ |
| /**************************************************************************************** |
| Portions of this file are derived from the following 3GPP standard: |
| |
| 3GPP TS 26.173 |
| ANSI-C code for the Adaptive Multi-Rate - Wideband (AMR-WB) speech codec |
| Available from http://www.3gpp.org |
| |
| (C) 2007, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC) |
| Permission to distribute, modify and use this file under the standard license |
| terms listed above has been obtained from the copyright holder. |
| ****************************************************************************************/ |
| /* |
| ------------------------------------------------------------------------------ |
| |
| |
| |
| Filename: deemphasis_32.cpp |
| |
| Date: 05/08/2004 |
| |
| ------------------------------------------------------------------------------ |
| REVISION HISTORY |
| |
| |
| Description: |
| |
| ------------------------------------------------------------------------------ |
| INPUT AND OUTPUT DEFINITIONS |
| |
| int16 x_hi[], (i) : input signal (bit31..16) |
| int16 x_lo[], (i) : input signal (bit15..4) |
| int16 y[], (o) : output signal (x16) |
| int16 mu, (i) Q15 : deemphasis factor |
| int16 L, (i) : vector size |
| int16 * mem (i/o) : memory (y[-1]) |
| |
| ------------------------------------------------------------------------------ |
| FUNCTION DESCRIPTION |
| |
| 32-bits filtering through 1/(1-mu z^-1) |
| |
| ------------------------------------------------------------------------------ |
| REQUIREMENTS |
| |
| |
| ------------------------------------------------------------------------------ |
| REFERENCES |
| |
| ------------------------------------------------------------------------------ |
| PSEUDO-CODE |
| |
| Deemphasis H(z) = 1/(1 - 0.68z^(-1)) where mu = 0.67999 in Q15 |
| |
| ------------------------------------------------------------------------------ |
| */ |
| |
| |
| /*---------------------------------------------------------------------------- |
| ; INCLUDES |
| ----------------------------------------------------------------------------*/ |
| |
| #include "pv_amr_wb_type_defs.h" |
| #include "pvamrwbdecoder_basic_op.h" |
| #include "pvamrwb_math_op.h" |
| #include "pvamrwbdecoder_acelp.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 |
| ----------------------------------------------------------------------------*/ |
| |
| void deemphasis_32( |
| int16 x_hi[], /* (i) : input signal (bit31..16) */ |
| int16 x_lo[], /* (i) : input signal (bit15..4) */ |
| int16 y[], /* (o) : output signal (x16) */ |
| int16 mu, /* (i) Q15 : deemphasis factor */ |
| int16 L, /* (i) : vector size */ |
| int16 * mem /* (i/o) : memory (y[-1]) */ |
| ) |
| { |
| int16 i; |
| int32 L_tmp; |
| int16 lo, hi; |
| |
| L_tmp = ((int32)x_hi[0]) << 16; |
| L_tmp += ((int32)x_lo[0]) << 4; |
| L_tmp = shl_int32(L_tmp, 3); |
| |
| L_tmp = fxp_mac_16by16(*mem, mu, L_tmp), |
| |
| L_tmp = shl_int32(L_tmp, 1); /* saturation can occur here */ |
| y[0] = amr_wb_round(L_tmp); |
| |
| lo = x_lo[1]; |
| hi = x_hi[1]; |
| for (i = 1; i < L - 1; i++) |
| { |
| L_tmp = ((int32)hi) << 16; |
| L_tmp += ((int32)lo) << 4; |
| L_tmp = shl_int32(L_tmp, 3); |
| L_tmp = fxp_mac_16by16(y[i - 1], mu, L_tmp), |
| L_tmp = shl_int32(L_tmp, 1); /* saturation can occur here */ |
| y[i] = amr_wb_round(L_tmp); |
| lo = x_lo[i+1]; |
| hi = x_hi[i+1]; |
| } |
| L_tmp = ((int32)hi) << 16; |
| L_tmp += ((int32)lo) << 4; |
| L_tmp = shl_int32(L_tmp, 3); |
| L_tmp = fxp_mac_16by16(y[i - 1], mu, L_tmp), |
| L_tmp = shl_int32(L_tmp, 1); /* saturation can occur here */ |
| y[i] = amr_wb_round(L_tmp); |
| |
| *mem = y[L - 1]; |
| |
| return; |
| } |
| |
