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MicroDexed/mixer8.cpp

133 lines
4.0 KiB

/* Audio Library for Teensy 3.X
* Copyright (c) 2014, Paul Stoffregen, paul@pjrc.com
*
* Development of this audio library was funded by PJRC.COM, LLC by sales of
* Teensy and Audio Adaptor boards. Please support PJRC's efforts to develop
* open source software by purchasing Teensy or other PJRC products.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice, development funding notice, and this permission
* notice shall be included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <Arduino.h>
#include "mixer8.h"
#include "utility/dspinst.h"
#if defined(__ARM_ARCH_7EM__)
#define MULTI_UNITYGAIN 65536
static void applyGain(int16_t *data, int32_t mult)
{
uint32_t *p = (uint32_t *)data;
const uint32_t *end = (uint32_t *)(data + AUDIO_BLOCK_SAMPLES);
do {
uint32_t tmp32 = *p; // read 2 samples from *data
int32_t val1 = signed_multiply_32x16b(mult, tmp32);
int32_t val2 = signed_multiply_32x16t(mult, tmp32);
val1 = signed_saturate_rshift(val1, 16, 0);
val2 = signed_saturate_rshift(val2, 16, 0);
*p++ = pack_16b_16b(val2, val1);
} while (p < end);
}
static void applyGainThenAdd(int16_t *data, const int16_t *in, int32_t mult)
{
uint32_t *dst = (uint32_t *)data;
const uint32_t *src = (uint32_t *)in;
const uint32_t *end = (uint32_t *)(data + AUDIO_BLOCK_SAMPLES);
if (mult == MULTI_UNITYGAIN) {
do {
uint32_t tmp32 = *dst;
*dst++ = signed_add_16_and_16(tmp32, *src++);
tmp32 = *dst;
*dst++ = signed_add_16_and_16(tmp32, *src++);
} while (dst < end);
} else {
do {
uint32_t tmp32 = *src++; // read 2 samples from *data
int32_t val1 = signed_multiply_32x16b(mult, tmp32);
int32_t val2 = signed_multiply_32x16t(mult, tmp32);
val1 = signed_saturate_rshift(val1, 16, 0);
val2 = signed_saturate_rshift(val2, 16, 0);
tmp32 = pack_16b_16b(val2, val1);
uint32_t tmp32b = *dst;
*dst++ = signed_add_16_and_16(tmp32, tmp32b);
} while (dst < end);
}
}
#elif defined(KINETISL)
#define MULTI_UNITYGAIN 256
static void applyGain(int16_t *data, int32_t mult)
{
const int16_t *end = data + AUDIO_BLOCK_SAMPLES;
do {
int32_t val = *data * mult;
*data++ = signed_saturate_rshift(val, 16, 0);
} while (data < end);
}
static void applyGainThenAdd(int16_t *dst, const int16_t *src, int32_t mult)
{
const int16_t *end = dst + AUDIO_BLOCK_SAMPLES;
if (mult == MULTI_UNITYGAIN) {
do {
int32_t val = *dst + *src++;
*dst++ = signed_saturate_rshift(val, 16, 0);
} while (dst < end);
} else {
do {
int32_t val = *dst + ((*src++ * mult) >> 8); // overflow possible??
*dst++ = signed_saturate_rshift(val, 16, 0);
} while (dst < end);
}
}
#endif
void AudioMixer8::update(void)
{
audio_block_t *in, *out=NULL;
unsigned int channel;
for (channel=0; channel < 8; channel++) {
if (!out) {
out = receiveWritable(channel);
if (out) {
int32_t mult = multiplier[channel];
if (mult != MULTI_UNITYGAIN) applyGain(out->data, mult);
}
} else {
in = receiveReadOnly(channel);
if (in) {
applyGainThenAdd(out->data, in->data, multiplier[channel]);
release(in);
}
}
}
if (out) {
transmit(out);
release(out);
}
}