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/*
* Copyright 2023 jacqueline <me@jacqueline.id.au>
*
* SPDX-License-Identifier: GPL-3.0-only
*/
#include "audio/resample.hpp"
#include <stdint.h>
#include <algorithm>
#include <cmath>
#include <cstdint>
#include <cstdlib>
#include <cstring>
#include <numeric>
#include "esp_log.h"
#include "speex/speex_resampler.h"
#include "sample.hpp"
namespace audio {
static constexpr int kQuality = SPEEX_RESAMPLER_QUALITY_MIN;
Resampler::Resampler(uint32_t source_sample_rate,
uint32_t target_sample_rate,
uint8_t num_channels)
: err_(0),
resampler_(speex_resampler_init(num_channels,
source_sample_rate,
target_sample_rate,
kQuality,
&err_)),
num_channels_(num_channels) {
speex_resampler_skip_zeros(resampler_);
assert(err_ == 0);
}
Resampler::~Resampler() {
speex_resampler_destroy(resampler_);
}
auto Resampler::sourceRate() -> uint32_t {
uint32_t input = 0;
uint32_t output = 0;
speex_resampler_get_rate(resampler_, &input, &output);
return input;
}
auto Resampler::Process(std::span<sample::Sample> input,
std::span<sample::Sample> output,
bool end_of_data) -> std::pair<size_t, size_t> {
uint32_t frames_used = input.size() / num_channels_;
uint32_t frames_produced = output.size() / num_channels_;
int err = speex_resampler_process_interleaved_int(
resampler_, input.data(), &frames_used, output.data(), &frames_produced);
assert(err == 0);
return {frames_used * num_channels_, frames_produced * num_channels_};
}
} // namespace audio
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