/*
 * Copyright (C) 2004-2010 NXP Software
 * Copyright (C) 2010 The Android Open Source Project
 *
 * 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.
 */

/************************************************************************************/
/*                                                                                  */
/*    Includes                                                                      */
/*                                                                                  */
/************************************************************************************/

#include "LVEQNB.h"
#include "LVEQNB_Coeffs.h"
#include "LVEQNB_Tables.h"

/************************************************************************************/
/*                                                                                  */
/*    Sample rate table                                                             */
/*                                                                                  */
/************************************************************************************/

/*
 * Sample rate table for converting between the enumerated type and the actual
 * frequency
 */
const LVM_UINT32 LVEQNB_SampleRateTab[] = {8000, /* 8kS/s  */
                                           11025, 12000, 16000, 22050, 24000,  32000,
                                           44100, 48000, 88200, 96000, 176400, 192000};

/************************************************************************************/
/*                                                                                  */
/*    Coefficient calculation tables                                                */
/*                                                                                  */
/************************************************************************************/

/*
 * Table for 2 * Pi / Fs
 */
const LVM_FLOAT LVEQNB_TwoPiOnFsTable[] = {
        LVEQNB_2PiOn_8000, /* 8kS/s */
        LVEQNB_2PiOn_11025, LVEQNB_2PiOn_12000, LVEQNB_2PiOn_16000,  LVEQNB_2PiOn_22050,
        LVEQNB_2PiOn_24000, LVEQNB_2PiOn_32000, LVEQNB_2PiOn_44100,  LVEQNB_2PiOn_48000,
        LVEQNB_2PiOn_88200, LVEQNB_2PiOn_96000, LVEQNB_2PiOn_176400, LVEQNB_2PiOn_192000};

/*
 * Gain table
 */
const LVM_FLOAT LVEQNB_GainTable[] = {
        LVEQNB_Gain_Neg15_dB, /* -15dB gain */
        LVEQNB_Gain_Neg14_dB, LVEQNB_Gain_Neg13_dB, LVEQNB_Gain_Neg12_dB, LVEQNB_Gain_Neg11_dB,
        LVEQNB_Gain_Neg10_dB, LVEQNB_Gain_Neg9_dB,  LVEQNB_Gain_Neg8_dB,  LVEQNB_Gain_Neg7_dB,
        LVEQNB_Gain_Neg6_dB,  LVEQNB_Gain_Neg5_dB,  LVEQNB_Gain_Neg4_dB,  LVEQNB_Gain_Neg3_dB,
        LVEQNB_Gain_Neg2_dB,  LVEQNB_Gain_Neg1_dB,  LVEQNB_Gain_0_dB, /* 0dB gain */
        LVEQNB_Gain_1_dB,     LVEQNB_Gain_2_dB,     LVEQNB_Gain_3_dB,     LVEQNB_Gain_4_dB,
        LVEQNB_Gain_5_dB,     LVEQNB_Gain_6_dB,     LVEQNB_Gain_7_dB,     LVEQNB_Gain_8_dB,
        LVEQNB_Gain_9_dB,     LVEQNB_Gain_10_dB,    LVEQNB_Gain_11_dB,    LVEQNB_Gain_12_dB,
        LVEQNB_Gain_13_dB,    LVEQNB_Gain_14_dB,    LVEQNB_Gain_15_dB}; /* +15dB gain */
/*
 * D table for 100 / (Gain + 1)
 */
const LVM_FLOAT LVEQNB_DTable[] = {
        LVEQNB_100D_Neg15_dB, /* -15dB gain */
        LVEQNB_100D_Neg14_dB, LVEQNB_100D_Neg13_dB, LVEQNB_100D_Neg12_dB, LVEQNB_100D_Neg11_dB,
        LVEQNB_100D_Neg10_dB, LVEQNB_100D_Neg9_dB,  LVEQNB_100D_Neg8_dB,  LVEQNB_100D_Neg7_dB,
        LVEQNB_100D_Neg6_dB,  LVEQNB_100D_Neg5_dB,  LVEQNB_100D_Neg4_dB,  LVEQNB_100D_Neg3_dB,
        LVEQNB_100D_Neg2_dB,  LVEQNB_100D_Neg1_dB,  LVEQNB_100D_0_dB}; /* 0dB gain */
/************************************************************************************/
/*                                                                                  */
/*    Filter polynomial coefficients                                                */
/*                                                                                  */
/************************************************************************************/

/*
 * Coefficients for calculating the cosine with the equation:
 *
 *  Cos(x) = (2^Shifts)*(a0 + a1*x + a2*x^2 + a3*x^3 + a4*x^4 + a5*x^5)
 *
 * These coefficients expect the input, x, to be in the range 0 to 32768 respresenting
 * a range of 0 to Pi. The output is in the range 32767 to -32768 representing the range
 * +1.0 to -1.0
 */
const LVM_INT16 LVEQNB_CosCoef[] = {3,      /* Shifts */
                                    4096,   /* a0 */
                                    -36,    /* a1 */
                                    -19725, /* a2 */
                                    -2671,  /* a3 */
                                    23730,  /* a4 */
                                    -9490}; /* a5 */

/*
 * Coefficients for calculating the cosine error with the equation:
 *
 *  CosErr(x) = (2^Shifts)*(a0 + a1*x + a2*x^2 + a3*x^3)
 *
 * These coefficients expect the input, x, to be in the range 0 to 32768 respresenting
 * a range of 0 to Pi/25. The output is in the range 0 to 32767 representing the range
 * 0.0 to 0.0078852986
 *
 * This is used to give a double precision cosine over the range 0 to Pi/25 using the
 * the equation:
 *
 * Cos(x) = 1.0 - CosErr(x)
 */
const LVM_INT16 LVEQNB_DPCosCoef[] = {1,     /* Shifts */
                                      0,     /* a0 */
                                      -6,    /* a1 */
                                      16586, /* a2 */
                                      -44};  /* a3 */