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Diffstat (limited to 'media/libstagefright/codecs/amrwb/src/agc2_amr_wb.cpp')
| -rw-r--r-- | media/libstagefright/codecs/amrwb/src/agc2_amr_wb.cpp | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/media/libstagefright/codecs/amrwb/src/agc2_amr_wb.cpp b/media/libstagefright/codecs/amrwb/src/agc2_amr_wb.cpp new file mode 100644 index 0000000..2e53d13 --- /dev/null +++ b/media/libstagefright/codecs/amrwb/src/agc2_amr_wb.cpp @@ -0,0 +1,190 @@ +/* ------------------------------------------------------------------ + * 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: agc2_amr_wb.cpp + + Date: 05/08/2007 + +------------------------------------------------------------------------------ + REVISION HISTORY + + + Description: + +------------------------------------------------------------------------------ + INPUT AND OUTPUT DEFINITIONS + + int16 * sig_in, (i) : postfilter input signal + int16 * sig_out, (i/o) : postfilter output signal + int16 l_trm (i) : subframe size + + +------------------------------------------------------------------------------ + FUNCTION DESCRIPTION + + Performs adaptive gain control + +------------------------------------------------------------------------------ + REQUIREMENTS + + +------------------------------------------------------------------------------ + REFERENCES + +------------------------------------------------------------------------------ + PSEUDO-CODE + +------------------------------------------------------------------------------ +*/ + + +/*---------------------------------------------------------------------------- +; INCLUDES +----------------------------------------------------------------------------*/ + +#include "pvamrwbdecoder_cnst.h" +#include "pvamrwbdecoder_acelp.h" +#include "pv_amr_wb_type_defs.h" +#include "pvamrwbdecoder_basic_op.h" +#include "pvamrwb_math_op.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 agc2_amr_wb( + int16 * sig_in, /* (i) : postfilter input signal */ + int16 * sig_out, /* (i/o) : postfilter output signal */ + int16 l_trm /* (i) : subframe size */ +) +{ + + int16 i, exp; + int16 gain_in, gain_out, g0; + int32 s; + + int16 temp; + + /* calculate gain_out with exponent */ + + temp = sig_out[0] >> 2; + s = fxp_mul_16by16(temp, temp) << 1; + for (i = 1; i < l_trm; i++) + { + temp = sig_out[i] >> 2; + s = mac_16by16_to_int32(s, temp, temp); + } + + + if (s == 0) + { + return; + } + exp = normalize_amr_wb(s) - 1; + gain_out = amr_wb_round(s << exp); + + /* calculate gain_in with exponent */ + + temp = sig_in[0] >> 2; + s = mul_16by16_to_int32(temp, temp); + for (i = 1; i < l_trm; i++) + { + temp = sig_in[i] >> 2; + s = mac_16by16_to_int32(s, temp, temp); + } + + + if (s == 0) + { + g0 = 0; + } + else + { + i = normalize_amr_wb(s); + gain_in = amr_wb_round(s << i); + exp -= i; + + /* + * g0 = sqrt(gain_in/gain_out) + */ + + s = div_16by16(gain_out, gain_in); + s = shl_int32(s, 7); /* s = gain_out / gain_in */ + s = shr_int32(s, exp); /* add exponent */ + + s = one_ov_sqrt(s); + g0 = amr_wb_round(shl_int32(s, 9)); + } + /* sig_out(n) = gain(n) sig_out(n) */ + + for (i = 0; i < l_trm; i++) + { + sig_out[i] = extract_h(shl_int32(fxp_mul_16by16(sig_out[i], g0), 3)); + + } + + return; +} + |