77 lines
2.8 KiB
C++
77 lines
2.8 KiB
C++
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/************************************************************************************
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*
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* D++, A Lightweight C++ library for Discord
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*
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* Copyright 2021 Craig Edwards and D++ contributors
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* (https://github.com/brainboxdotcc/DPP/graphs/contributors)
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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************************************************************************************/
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#pragma once
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#include <numeric>
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namespace dpp {
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/**
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* @brief A class for audio mixing operations using x64 instructions.
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*/
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class audio_mixer {
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public:
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/*
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* @brief The number of 32-bit values per CPU register.
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*/
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inline static constexpr int32_t byte_blocks_per_register{ 2 };
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/**
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* @brief Collect a single register worth of data from data_in, apply gain and increment, and store the result in data_out.
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* This version uses x64 instructions.
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*
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* @param data_in Pointer to the input array of int32_t values.
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* @param data_out Pointer to the output array of int16_t values.
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* @param current_gain The gain to be applied to the elements.
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* @param increment The increment value to be added to each element.
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*/
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inline static void collect_single_register(int32_t* data_in, int16_t* data_out, float current_gain, float increment) {
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for (uint64_t x = 0; x < byte_blocks_per_register; ++x) {
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auto increment_new = increment * x;
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auto current_gain_new = current_gain + increment_new;
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auto current_sample_new = data_in[x] * current_gain_new;
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if (current_sample_new >= std::numeric_limits<int16_t>::max()) {
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current_sample_new = std::numeric_limits<int16_t>::max();
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}
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else if (current_sample_new <= std::numeric_limits<int16_t>::min()) {
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current_sample_new = std::numeric_limits<int16_t>::min();
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}
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data_out[x] = static_cast<int16_t>(current_sample_new);
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}
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}
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/**
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* @brief Combine a register worth of elements from decoded_data and store the result in up_sampled_vector.
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* This version uses x64 instructions.
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*
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* @param up_sampled_vector Pointer to the array of int32_t values.
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* @param decoded_data Pointer to the array of int16_t values.
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*/
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inline static void combine_samples(int32_t* up_sampled_vector, const int16_t* decoded_data) {
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for (uint64_t x = 0; x < byte_blocks_per_register; ++x) {
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up_sampled_vector[x] += static_cast<int32_t>(decoded_data[x]);
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}
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}
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};
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} // namespace dpp
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