43 lines
1.5 KiB
C++
43 lines
1.5 KiB
C++
// Copyright 2018 yuzu Emulator Project
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// Licensed under GPLv2 or any later version
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// Refer to the license.txt file included.
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#pragma once
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#include <array>
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#include <vector>
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#include "audio_core/algorithm/filter.h"
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#include "common/common_types.h"
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namespace AudioCore {
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struct InterpolationState {
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static constexpr std::size_t lanczos_taps = 4;
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static constexpr std::size_t history_size = lanczos_taps * 2 - 1;
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double current_ratio = 0.0;
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CascadingFilter nyquist;
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std::array<std::array<s16, 2>, history_size> history = {};
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double position = 0;
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};
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/// Interpolates input signal to produce output signal.
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/// @param input The signal to interpolate.
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/// @param ratio Interpolation ratio.
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/// ratio > 1.0 results in fewer output samples.
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/// ratio < 1.0 results in more output samples.
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/// @returns Output signal.
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std::vector<s16> Interpolate(InterpolationState& state, std::vector<s16> input, double ratio);
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/// Interpolates input signal to produce output signal.
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/// @param input The signal to interpolate.
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/// @param input_rate The sample rate of input.
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/// @param output_rate The desired sample rate of the output.
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/// @returns Output signal.
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inline std::vector<s16> Interpolate(InterpolationState& state, std::vector<s16> input,
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u32 input_rate, u32 output_rate) {
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const double ratio = static_cast<double>(input_rate) / static_cast<double>(output_rate);
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return Interpolate(state, std::move(input), ratio);
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}
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} // namespace AudioCore
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