silero_vad_onnx/vad_iterator.cpp

#include "vad_iterator.h"
#include <cmath>
#include <cstdio>
#include <cstring>
#include <memory>


void VadIterator::init_onnx_model(const std::string& model_path) {
    init_engine_threads(1, 1);
    session = std::make_shared<Ort::Session>(env, model_path.c_str(), session_options);
}

void VadIterator::init_engine_threads(int inter_threads, int intra_threads) {
    session_options.SetIntraOpNumThreads(intra_threads);
    session_options.SetInterOpNumThreads(inter_threads);
    session_options.SetGraphOptimizationLevel(ORT_ENABLE_ALL);
}

void VadIterator::reset_states() {
    std::memset(_state.data(), 0, _state.size() * sizeof(float));
    triggered = false;
    temp_end = 0;
    current_sample = 0;
    prev_end = next_start = 0;
    speeches.clear();
    current_speech = timestamp_t();
    std::fill(_context.begin(), _context.end(), 0.0f);
}

void VadIterator::predict(const std::vector<float>& data_chunk) {
    std::vector<float> new_data(effective_window_size, 0.0f);
    std::copy(_context.begin(), _context.end(), new_data.begin());
    std::copy(data_chunk.begin(), data_chunk.end(), new_data.begin() + context_samples);
    input = new_data;

    Ort::Value input_ort = Ort::Value::CreateTensor<float>(
        memory_info, input.data(), input.size(), input_node_dims, 2);
    Ort::Value state_ort = Ort::Value::CreateTensor<float>(
        memory_info, _state.data(), _state.size(), state_node_dims, 3);
    Ort::Value sr_ort = Ort::Value::CreateTensor<int64_t>(
        memory_info, sr.data(), sr.size(), sr_node_dims, 1);

    ort_inputs.clear();
    ort_inputs.emplace_back(std::move(input_ort));
    ort_inputs.emplace_back(std::move(state_ort));
    ort_inputs.emplace_back(std::move(sr_ort));

    ort_outputs = session->Run(
        Ort::RunOptions{nullptr},
        input_node_names.data(), ort_inputs.data(), ort_inputs.size(),
        output_node_names.data(), output_node_names.size());

    float speech_prob = ort_outputs[0].GetTensorMutableData<float>()[0];
    float* stateN = ort_outputs[1].GetTensorMutableData<float>();
    std::memcpy(_state.data(), stateN, size_state * sizeof(float));

    current_sample += static_cast<unsigned int>(window_size_samples);

    if (speech_prob >= threshold) {
        if (temp_end != 0) {
            temp_end = 0;
            if (next_start < prev_end)
                next_start = current_sample - window_size_samples;
        }
        if (!triggered) {
            triggered = true;
            current_speech.start = current_sample - window_size_samples;
        }
        std::copy(new_data.end() - context_samples, new_data.end(), _context.begin());
        return;
    }

    if (triggered && ((current_sample - current_speech.start) > max_speech_samples)) {
        if (prev_end > 0) {
            current_speech.end = prev_end;
            speeches.push_back(current_speech);
            current_speech = timestamp_t();
            if (next_start < prev_end)
                triggered = false;
            else
                current_speech.start = next_start;
            prev_end = 0;
            next_start = 0;
            temp_end = 0;
        } else {
            current_speech.end = current_sample;
            speeches.push_back(current_speech);
            current_speech = timestamp_t();
            prev_end = 0;
            next_start = 0;
            temp_end = 0;
            triggered = false;
        }
        std::copy(new_data.end() - context_samples, new_data.end(), _context.begin());
        return;
    }

    if ((speech_prob >= (threshold - 0.15)) && (speech_prob < threshold)) {
        std::copy(new_data.end() - context_samples, new_data.end(), _context.begin());
        return;
    }

    if (speech_prob < (threshold - 0.15)) {
        if (triggered) {
            if (temp_end == 0)
                temp_end = current_sample;
            if (current_sample - temp_end > min_silence_samples_at_max_speech)
                prev_end = temp_end;
            if ((current_sample - temp_end) >= min_silence_samples) {
                current_speech.end = temp_end;
                if (current_speech.end - current_speech.start > min_speech_samples) {
                    speeches.push_back(current_speech);
                    current_speech = timestamp_t();
                    prev_end = 0;
                    next_start = 0;
                    temp_end = 0;
                    triggered = false;
                }
            }
        }
        std::copy(new_data.end() - context_samples, new_data.end(), _context.begin());
        return;
    }
}

void VadIterator::process(const std::vector<float>& input_wav) {
    reset_states();
    audio_length_samples = static_cast<int>(input_wav.size());

    for (size_t j = 0; j < static_cast<size_t>(audio_length_samples); j += static_cast<size_t>(window_size_samples)) {
        if (j + static_cast<size_t>(window_size_samples) > static_cast<size_t>(audio_length_samples))
            break;
        std::vector<float> chunk(&input_wav[j], &input_wav[j] + window_size_samples);
        predict(chunk);
    }

    if (current_speech.start >= 0) {
        current_speech.end = audio_length_samples;
        speeches.push_back(current_speech);
        current_speech = timestamp_t();
        prev_end = 0;
        next_start = 0;
        temp_end = 0;
        triggered = false;
    }
}

const std::vector<timestamp_t>& VadIterator::get_speech_timestamps() const {
    return speeches;
}

void VadIterator::reset() {
    reset_states();
}

// 构造函数实现
VadIterator::VadIterator(const std::string ModelPath,
                         int Sample_rate,
                         int windows_frame_size,
                         float Threshold,
                         int min_silence_duration_ms,
                         int speech_pad_ms,
                         int min_speech_duration_ms,
                         float max_speech_duration_s)
    : sample_rate(Sample_rate),
      threshold(Threshold),
      speech_pad_samples(speech_pad_ms),
      prev_end(0),
      memory_info(Ort::MemoryInfo::CreateCpu(OrtAllocatorType::OrtDeviceAllocator, OrtMemType::OrtMemTypeDefault))
      {

    sr_per_ms = sample_rate / 1000;
    window_size_samples = windows_frame_size * sr_per_ms;
    effective_window_size = window_size_samples + context_samples;

    input_node_dims[0] = 1;
    input_node_dims[1] = effective_window_size;

    _state.resize(size_state);
    sr.resize(1);
    sr[0] = sample_rate;
    _context.assign(context_samples, 0.0f);

    min_speech_samples = sr_per_ms * min_speech_duration_ms;

    if (max_speech_duration_s < 0) {
        max_speech_samples = std::numeric_limits<float>::infinity();
    } else {
        max_speech_samples = (sample_rate * max_speech_duration_s - window_size_samples - 2 * speech_pad_samples);
    }

    min_silence_samples = sr_per_ms * min_silence_duration_ms;
    min_silence_samples_at_max_speech = sr_per_ms * 98;
    
    init_onnx_model(ModelPath);
}