/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
/*
* This file contains the resampling functions for 22 kHz.
* The description header can be found in signal_processing_library.h
*
*/
#include "signal_processing_library.h"
#include "resample_by_2_internal.h"
// Declaration of internally used functions
static void WebRtcSpl_32khzTo22khzIntToShort(const WebRtc_Word32 *In, WebRtc_Word16 *Out,
const WebRtc_Word32 K);
void WebRtcSpl_32khzTo22khzIntToInt(const WebRtc_Word32 *In, WebRtc_Word32 *Out,
const WebRtc_Word32 K);
// interpolation coefficients
static const WebRtc_Word16 kCoefficients32To22[5][9] = {
{127, -712, 2359, -6333, 23456, 16775, -3695, 945, -154},
{-39, 230, -830, 2785, 32366, -2324, 760, -218, 38},
{117, -663, 2222, -6133, 26634, 13070, -3174, 831, -137},
{-77, 457, -1677, 5958, 31175, -4136, 1405, -408, 71},
{ 98, -560, 1900, -5406, 29240, 9423, -2480, 663, -110}
};
//////////////////////
// 22 kHz -> 16 kHz //
//////////////////////
// number of subblocks; options: 1, 2, 4, 5, 10
#define SUB_BLOCKS_22_16 5
// 22 -> 16 resampler
void WebRtcSpl_Resample22khzTo16khz(const WebRtc_Word16* in, WebRtc_Word16* out,
WebRtcSpl_State22khzTo16khz* state, WebRtc_Word32* tmpmem)
{
int k;
// process two blocks of 10/SUB_BLOCKS_22_16 ms (to reduce temp buffer size)
for (k = 0; k < SUB_BLOCKS_22_16; k++)
{
///// 22 --> 44 /////
// WebRtc_Word16 in[220/SUB_BLOCKS_22_16]
// WebRtc_Word32 out[440/SUB_BLOCKS_22_16]
/////
WebRtcSpl_UpBy2ShortToInt(in, 220 / SUB_BLOCKS_22_16, tmpmem + 16, state->S_22_44);
///// 44 --> 32 /////
// WebRtc_Word32 in[440/SUB_BLOCKS_22_16]
// WebRtc_Word32 out[320/SUB_BLOCKS_22_16]
/////
// copy state to and from input array
tmpmem[8] = state->S_44_32[0];
tmpmem[9] = state->S_44_32[1];
tmpmem[10] = state->S_44_32[2];
tmpmem[11] = state->S_44_32[3];
tmpmem[12] = state->S_44_32[4];
tmpmem[13] = state->S_44_32[5];
tmpmem[14] = state->S_44_32[6];
tmpmem[15] = state->S_44_32[7];
state->S_44_32[0] = tmpmem[440 / SUB_BLOCKS_22_16 + 8];
state->S_44_32[1] = tmpmem[440 / SUB_BLOCKS_22_16 + 9];
state->S_44_32[2] = tmpmem[440 / SUB_BLOCKS_22_16 + 10];
state->S_44_32[3] = tmpmem[440 / SUB_BLOCKS_22_16 + 11];
state->S_44_32[4] = tmpmem[440 / SUB_BLOCKS_22_16 + 12];
state->S_44_32[5] = tmpmem[440 / SUB_BLOCKS_22_16 + 13];
state->S_44_32[6] = tmpmem[440 / SUB_BLOCKS_22_16 + 14];
state->S_44_32[7] = tmpmem[440 / SUB_BLOCKS_22_16 + 15];
WebRtcSpl_Resample44khzTo32khz(tmpmem + 8, tmpmem, 40 / SUB_BLOCKS_22_16);
///// 32 --> 16 /////
// WebRtc_Word32 in[320/SUB_BLOCKS_22_16]
// WebRtc_Word32 out[160/SUB_BLOCKS_22_16]
/////
WebRtcSpl_DownBy2IntToShort(tmpmem, 320 / SUB_BLOCKS_22_16, out, state->S_32_16);
// move input/output pointers 10/SUB_BLOCKS_22_16 ms seconds ahead
in += 220 / SUB_BLOCKS_22_16;
out += 160 / SUB_BLOCKS_22_16;
}
}
// initialize state of 22 -> 16 resampler
void WebRtcSpl_ResetResample22khzTo16khz(WebRtcSpl_State22khzTo16khz* state)
{
int k;
for (k = 0; k < 8; k++)
{
state->S_22_44[k] = 0;
state->S_44_32[k] = 0;
state->S_32_16[k] = 0;
}
}
//////////////////////
// 16 kHz -> 22 kHz //
//////////////////////
// number of subblocks; options: 1, 2, 4, 5, 10
#define SUB_BLOCKS_16_22 4
// 16 -> 22 resampler
void WebRtcSpl_Resample16khzTo22khz(const WebRtc_Word16* in, WebRtc_Word16* out,
WebRtcSpl_State16khzTo22khz* state, WebRtc_Word32* tmpmem)
{
int k;
// process two blocks of 10/SUB_BLOCKS_16_22 ms (to reduce temp buffer size)
for (k = 0; k < SUB_BLOCKS_16_22; k++)
{
///// 16 --> 32 /////
// WebRtc_Word16 in[160/SUB_BLOCKS_16_22]
// WebRtc_Word32 out[320/SUB_BLOCKS_16_22]
/////
WebRtcSpl_UpBy2ShortToInt(in, 160 / SUB_BLOCKS_16_22, tmpmem + 8, state->S_16_32);
///// 32 --> 22 /////
// WebRtc_Word32 in[320/SUB_BLOCKS_16_22]
// WebRtc_Word32 out[220/SUB_BLOCKS_16_22]
/////
// copy state to and from input array
tmpmem[0] = state->S_32_22[0];
tmpmem[1] = state->S_32_22[1];
tmpmem[2] = state->S_32_22[2];
tmpmem[3] = state->S_32_22[3];
tmpmem[4] = state->S_32_22[4];
tmpmem[5] = state->S_32_22[5];
tmpmem[6] = state->S_32_22[6];
tmpmem[7] = state->S_32_22[7];
state->S_32_22[0] = tmpmem[320 / SUB_BLOCKS_16_22];
state->S_32_22[1] = tmpmem[320 / SUB_BLOCKS_16_22 + 1];
state->S_32_22[2] = tmpmem[320 / SUB_BLOCKS_16_22 + 2];
state->S_32_22[3] = tmpmem[320 / SUB_BLOCKS_16_22 + 3];
state->S_32_22[4] = tmpmem[320 / SUB_BLOCKS_16_22 + 4];
state->S_32_22[5] = tmpmem[320 / SUB_BLOCKS_16_22 + 5];
state->S_32_22[6] = tmpmem[320 / SUB_BLOCKS_16_22 + 6];
state->S_32_22[7] = tmpmem[320 / SUB_BLOCKS_16_22 + 7];
WebRtcSpl_32khzTo22khzIntToShort(tmpmem, out, 20 / SUB_BLOCKS_16_22);
// move input/output pointers 10/SUB_BLOCKS_16_22 ms seconds ahead
in += 160 / SUB_BLOCKS_16_22;
out += 220 / SUB_BLOCKS_16_22;
}
}
// initialize state of 16 -> 22 resampler
void WebRtcSpl_ResetResample16khzTo22khz(WebRtcSpl_State16khzTo22khz* state)
{
int k;
for (k = 0; k < 8; k++)
{
state->S_16_32[k] = 0;
state->S_32_22[k] = 0;
}
}
//////////////////////
// 22 kHz -> 8 kHz //
//////////////////////
// number of subblocks; options: 1, 2, 5, 10
#define SUB_BLOCKS_22_8 2
// 22 -> 8 resampler
void WebRtcSpl_Resample22khzTo8khz(const WebRtc_Word16* in, WebRtc_Word16* out,
WebRtcSpl_State22khzTo8khz* state, WebRtc_Word32* tmpmem)
{
int k;
// process two blocks of 10/SUB_BLOCKS_22_8 ms (to reduce temp buffer size)
for (k = 0; k < SUB_BLOCKS_22_8; k++)
{
///// 22 --> 22 lowpass /////
// WebRtc_Word16 in[220/SUB_BLOCKS_22_8]
// WebRtc_Word32 out[220/SUB_BLOCKS_22_8]
/////
WebRtcSpl_LPBy2ShortToInt(in, 220 / SUB_BLOCKS_22_8, tmpmem + 16, state->S_22_22);
///// 22 --> 16 /////
// WebRtc_Word32 in[220/SUB_BLOCKS_22_8]
// WebRtc_Word32 out[160/SUB_BLOCKS_22_8]
/////
// copy state to and from input array
tmpmem[8] = state->S_22_16[0];
tmpmem[9] = state->S_22_16[1];
tmpmem[10] = state->S_22_16[2];
tmpmem[11] = state->S_22_16[3];
tmpmem[12] = state->S_22_16[4];
tmpmem[13] = state->S_22_16[5];
tmpmem[14] = state->S_22_16[6];
tmpmem[15] = state->S_22_16[7];
state->S_22_16[0] = tmpmem[220 / SUB_BLOCKS_22_8 + 8];
state->S_22_16[1] = tmpmem[220 / SUB_BLOCKS_22_8 + 9];
state->S_22_16[2] = tmpmem[220 / SUB_BLOCKS_22_8 + 10];
state->S_22_16[3] = tmpmem[220 / SUB_BLOCKS_22_8 + 11];
state->S_22_16[4] = tmpmem[220 / SUB_BLOCKS_22_8 + 12];
state->S_22_16[5] = tmpmem[220 / SUB_BLOCKS_22_8 + 13];
state->S_22_16[6] = tmpmem[220 / SUB_BLOCKS_22_8 + 14];
state->S_22_16[7] = tmpmem[220 / SUB_BLOCKS_22_8 + 15];
WebRtcSpl_Resample44khzTo32khz(tmpmem + 8, tmpmem, 20 / SUB_BLOCKS_22_8);
///// 16 --> 8 /////
// WebRtc_Word32 in[160/SUB_BLOCKS_22_8]
// WebRtc_Word32 out[80/SUB_BLOCKS_22_8]
/////
WebRtcSpl_DownBy2IntToShort(tmpmem, 160 / SUB_BLOCKS_22_8, out, state->S_16_8);
// move input/output pointers 10/SUB_BLOCKS_22_8 ms seconds ahead
in += 220 / SUB_BLOCKS_22_8;
out += 80 / SUB_BLOCKS_22_8;
}
}
// initialize state of 22 -> 8 resampler
void WebRtcSpl_ResetResample22khzTo8khz(WebRtcSpl_State22khzTo8khz* state)
{
int k;
for (k = 0; k < 8; k++)
{
state->S_22_22[k] = 0;
state->S_22_22[k + 8] = 0;
state->S_22_16[k] = 0;
state->S_16_8[k] = 0;
}
}
//////////////////////
// 8 kHz -> 22 kHz //
//////////////////////
// number of subblocks; options: 1, 2, 5, 10
#define SUB_BLOCKS_8_22 2
// 8 -> 22 resampler
void WebRtcSpl_Resample8khzTo22khz(const WebRtc_Word16* in, WebRtc_Word16* out,
WebRtcSpl_State8khzTo22khz* state, WebRtc_Word32* tmpmem)
{
int k;
// process two blocks of 10/SUB_BLOCKS_8_22 ms (to reduce temp buffer size)
for (k = 0; k < SUB_BLOCKS_8_22; k++)
{
///// 8 --> 16 /////
// WebRtc_Word16 in[80/SUB_BLOCKS_8_22]
// WebRtc_Word32 out[160/SUB_BLOCKS_8_22]
/////
WebRtcSpl_UpBy2ShortToInt(in, 80 / SUB_BLOCKS_8_22, tmpmem + 18, state->S_8_16);
///// 16 --> 11 /////
// WebRtc_Word32 in[160/SUB_BLOCKS_8_22]
// WebRtc_Word32 out[110/SUB_BLOCKS_8_22]
/////
// copy state to and from input array
tmpmem[10] = state->S_16_11[0];
tmpmem[11] = state->S_16_11[1];
tmpmem[12] = state->S_16_11[2];
tmpmem[13] = state->S_16_11[3];
tmpmem[14] = state->S_16_11[4];
tmpmem[15] = state->S_16_11[5];
tmpmem[16] = state->S_16_11[6];
tmpmem[17] = state->S_16_11[7];
state->S_16_11[0] = tmpmem[160 / SUB_BLOCKS_8_22 + 10];
state->S_16_11[1] = tmpmem[160 / SUB_BLOCKS_8_22 + 11];
state->S_16_11[2] = tmpmem[160 / SUB_BLOCKS_8_22 + 12];
state->S_16_11[3] = tmpmem[160 / SUB_BLOCKS_8_22 + 13];
state->S_16_11[4] = tmpmem[160 / SUB_BLOCKS_8_22 + 14];
state->S_16_11[5] = tmpmem[160 / SUB_BLOCKS_8_22 + 15];
state->S_16_11[6] = tmpmem[160 / SUB_BLOCKS_8_22 + 16];
state->S_16_11[7] = tmpmem[160 / SUB_BLOCKS_8_22 + 17];
WebRtcSpl_32khzTo22khzIntToInt(tmpmem + 10, tmpmem, 10 / SUB_BLOCKS_8_22);
///// 11 --> 22 /////
// WebRtc_Word32 in[110/SUB_BLOCKS_8_22]
// WebRtc_Word16 out[220/SUB_BLOCKS_8_22]
/////
WebRtcSpl_UpBy2IntToShort(tmpmem, 110 / SUB_BLOCKS_8_22, out, state->S_11_22);
// move input/output pointers 10/SUB_BLOCKS_8_22 ms seconds ahead
in += 80 / SUB_BLOCKS_8_22;
out += 220 / SUB_BLOCKS_8_22;
}
}
// initialize state of 8 -> 22 resampler
void WebRtcSpl_ResetResample8khzTo22khz(WebRtcSpl_State8khzTo22khz* state)
{
int k;
for (k = 0; k < 8; k++)
{
state->S_8_16[k] = 0;
state->S_16_11[k] = 0;
state->S_11_22[k] = 0;
}
}
// compute two inner-products and store them to output array
static void WebRtcSpl_DotProdIntToInt(const WebRtc_Word32* in1, const WebRtc_Word32* in2,
const WebRtc_Word16* coef_ptr, WebRtc_Word32* out1,
WebRtc_Word32* out2)
{
WebRtc_Word32 tmp1 = 16384;
WebRtc_Word32 tmp2 = 16384;
WebRtc_Word16 coef;
coef = coef_ptr[0];
tmp1 += coef * in1[0];
tmp2 += coef * in2[-0];
coef = coef_ptr[1];
tmp1 += coef * in1[1];
tmp2 += coef * in2[-1];
coef = coef_ptr[2];
tmp1 += coef * in1[2];
tmp2 += coef * in2[-2];
coef = coef_ptr[3];
tmp1 += coef * in1[3];
tmp2 += coef * in2[-3];
coef = coef_ptr[4];
tmp1 += coef * in1[4];
tmp2 += coef * in2[-4];
coef = coef_ptr[5];
tmp1 += coef * in1[5];
tmp2 += coef * in2[-5];
coef = coef_ptr[6];
tmp1 += coef * in1[6];
tmp2 += coef * in2[-6];
coef = coef_ptr[7];
tmp1 += coef * in1[7];
tmp2 += coef * in2[-7];
coef = coef_ptr[8];
*out1 = tmp1 + coef * in1[8];
*out2 = tmp2 + coef * in2[-8];
}
// compute two inner-products and store them to output array
static void WebRtcSpl_DotProdIntToShort(const WebRtc_Word32* in1, const WebRtc_Word32* in2,
const WebRtc_Word16* coef_ptr, WebRtc_Word16* out1,
WebRtc_Word16* out2)
{
WebRtc_Word32 tmp1 = 16384;
WebRtc_Word32 tmp2 = 16384;
WebRtc_Word16 coef;
coef = coef_ptr[0];
tmp1 += coef * in1[0];
tmp2 += coef * in2[-0];
coef = coef_ptr[1];
tmp1 += coef * in1[1];
tmp2 += coef * in2[-1];
coef = coef_ptr[2];
tmp1 += coef * in1[2];
tmp2 += coef * in2[-2];
coef = coef_ptr[3];
tmp1 += coef * in1[3];
tmp2 += coef * in2[-3];
coef = coef_ptr[4];
tmp1 += coef * in1[4];
tmp2 += coef * in2[-4];
coef = coef_ptr[5];
tmp1 += coef * in1[5];
tmp2 += coef * in2[-5];
coef = coef_ptr[6];
tmp1 += coef * in1[6];
tmp2 += coef * in2[-6];
coef = coef_ptr[7];
tmp1 += coef * in1[7];
tmp2 += coef * in2[-7];
coef = coef_ptr[8];
tmp1 += coef * in1[8];
tmp2 += coef * in2[-8];
// scale down, round and saturate
tmp1 >>= 15;
if (tmp1 > (WebRtc_Word32)0x00007FFF)
tmp1 = 0x00007FFF;
if (tmp1 < (WebRtc_Word32)0xFFFF8000)
tmp1 = 0xFFFF8000;
tmp2 >>= 15;
if (tmp2 > (WebRtc_Word32)0x00007FFF)
tmp2 = 0x00007FFF;
if (tmp2 < (WebRtc_Word32)0xFFFF8000)
tmp2 = 0xFFFF8000;
*out1 = (WebRtc_Word16)tmp1;
*out2 = (WebRtc_Word16)tmp2;
}
// Resampling ratio: 11/16
// input: WebRtc_Word32 (normalized, not saturated) :: size 16 * K
// output: WebRtc_Word32 (shifted 15 positions to the left, + offset 16384) :: size 11 * K
// K: Number of blocks
void WebRtcSpl_32khzTo22khzIntToInt(const WebRtc_Word32* In,
WebRtc_Word32* Out,
const WebRtc_Word32 K)
{
/////////////////////////////////////////////////////////////
// Filter operation:
//
// Perform resampling (16 input samples -> 11 output samples);
// process in sub blocks of size 16 samples.
WebRtc_Word32 m;
for (m = 0; m < K; m++)
{
// first output sample
Out[0] = ((WebRtc_Word32)In[3] << 15) + (1 << 14);
// sum and accumulate filter coefficients and input samples
WebRtcSpl_DotProdIntToInt(&In[0], &In[22], kCoefficients32To22[0], &Out[1], &Out[10]);
// sum and accumulate filter coefficients and input samples
WebRtcSpl_DotProdIntToInt(&In[2], &In[20], kCoefficients32To22[1], &Out[2], &Out[9]);
// sum and accumulate filter coefficients and input samples
WebRtcSpl_DotProdIntToInt(&In[3], &In[19], kCoefficients32To22[2], &Out[3], &Out[8]);
// sum and accumulate filter coefficients and input samples
WebRtcSpl_DotProdIntToInt(&In[5], &In[17], kCoefficients32To22[3], &Out[4], &Out[7]);
// sum and accumulate filter coefficients and input samples
WebRtcSpl_DotProdIntToInt(&In[6], &In[16], kCoefficients32To22[4], &Out[5], &Out[6]);
// update pointers
In += 16;
Out += 11;
}
}
// Resampling ratio: 11/16
// input: WebRtc_Word32 (normalized, not saturated) :: size 16 * K
// output: WebRtc_Word16 (saturated) :: size 11 * K
// K: Number of blocks
void WebRtcSpl_32khzTo22khzIntToShort(const WebRtc_Word32 *In,
WebRtc_Word16 *Out,
const WebRtc_Word32 K)
{
/////////////////////////////////////////////////////////////
// Filter operation:
//
// Perform resampling (16 input samples -> 11 output samples);
// process in sub blocks of size 16 samples.
WebRtc_Word32 tmp;
WebRtc_Word32 m;
for (m = 0; m < K; m++)
{
// first output sample
tmp = In[3];
if (tmp > (WebRtc_Word32)0x00007FFF)
tmp = 0x00007FFF;
if (tmp < (WebRtc_Word32)0xFFFF8000)
tmp = 0xFFFF8000;
Out[0] = (WebRtc_Word16)tmp;
// sum and accumulate filter coefficients and input samples
WebRtcSpl_DotProdIntToShort(&In[0], &In[22], kCoefficients32To22[0], &Out[1], &Out[10]);
// sum and accumulate filter coefficients and input samples
WebRtcSpl_DotProdIntToShort(&In[2], &In[20], kCoefficients32To22[1], &Out[2], &Out[9]);
// sum and accumulate filter coefficients and input samples
WebRtcSpl_DotProdIntToShort(&In[3], &In[19], kCoefficients32To22[2], &Out[3], &Out[8]);
// sum and accumulate filter coefficients and input samples
WebRtcSpl_DotProdIntToShort(&In[5], &In[17], kCoefficients32To22[3], &Out[4], &Out[7]);
// sum and accumulate filter coefficients and input samples
WebRtcSpl_DotProdIntToShort(&In[6], &In[16], kCoefficients32To22[4], &Out[5], &Out[6]);
// update pointers
In += 16;
Out += 11;
}
}