samples/SpeechRecognition/src/Main.cpp

//
// Copyright © 2020 Arm Ltd and Contributors. All rights reserved.
// SPDX-License-Identifier: MIT
//
#include <iostream>
#include <map>
#include <vector>
#include <algorithm>
#include <cmath>

#include "CmdArgsParser.hpp"
#include "ArmnnNetworkExecutor.hpp"
#include "AudioCapture.hpp"
#include "Preprocess.hpp"
#include "Decoder.hpp"
#include "SpeechRecognitionPipeline.hpp"


using InferenceResult = std::vector<int8_t>;
using InferenceResults = std::vector<InferenceResult>;

const std::string AUDIO_FILE_PATH = "--audio-file-path";
const std::string MODEL_FILE_PATH = "--model-file-path";
const std::string LABEL_PATH = "--label-path";
const std::string PREFERRED_BACKENDS = "--preferred-backends";
const std::string HELP = "--help";

std::map<int, std::string> labels = {
        {0, "a" },
        {1, "b" },
        {2, "c" },
        {3, "d" },
        {4, "e" },
        {5, "f" },
        {6, "g" },
        {7, "h" },
        {8, "i" },
        {9, "j" },
        {10,"k" },
        {11,"l" },
        {12,"m" },
        {13,"n" },
        {14,"o" },
        {15,"p" },
        {16,"q" },
        {17,"r" },
        {18,"s" },
        {19,"t" },
        {20,"u" },
        {21,"v" },
        {22,"w" },
        {23,"x" },
        {24,"y" },
        {25,"z" },
        {26, "\'" },
        {27, " "},
        {28,"$" }
};

/*
 * The accepted options for this Speech Recognition executable
 */
static std::map<std::string, std::string> CMD_OPTIONS = {
        {AUDIO_FILE_PATH, "[REQUIRED] Path to the Audio file to run speech recognition on"},
        {MODEL_FILE_PATH, "[REQUIRED] Path to the Speech Recognition model to use"},
        {PREFERRED_BACKENDS, "[OPTIONAL] Takes the preferred backends in preference order, separated by comma."
                             " For example: CpuAcc,GpuAcc,CpuRef. Accepted options: [CpuAcc, CpuRef, GpuAcc]."
                             " Defaults to CpuAcc,CpuRef"}
};

/*
 * Reads the user supplied backend preference, splits it by comma, and returns an ordered vector
 */
std::vector<armnn::BackendId> GetPreferredBackendList(const std::string& preferredBackends)
{
    std::vector<armnn::BackendId> backends;
    std::stringstream ss(preferredBackends);

    while(ss.good())
    {
        std::string backend;
        std::getline( ss, backend, ',' );
        backends.emplace_back(backend);
    }
    return backends;
}

int main(int argc, char *argv[])
{
    // Wav2Letter ASR SETTINGS
    int             SAMP_FREQ                  = 16000;
    int             FRAME_LEN_MS               = 32;
    int             FRAME_LEN_SAMPLES          = SAMP_FREQ * FRAME_LEN_MS * 0.001;
    int             NUM_MFCC_FEATS             = 13;
    int             MFCC_WINDOW_LEN            = 512;
    int             MFCC_WINDOW_STRIDE         = 160;
    const int       NUM_MFCC_VECTORS           = 296;
    int             SAMPLES_PER_INFERENCE      = MFCC_WINDOW_LEN + ((NUM_MFCC_VECTORS -1) * MFCC_WINDOW_STRIDE);
    int             MEL_LO_FREQ                = 0;
    int             MEL_HI_FREQ                = 8000;
    int             NUM_FBANK_BIN              = 128;
    int             INPUT_WINDOW_LEFT_CONTEXT  = 98;
    int             INPUT_WINDOW_RIGHT_CONTEXT = 98;
    int             INPUT_WINDOW_INNER_CONTEXT = NUM_MFCC_VECTORS -
            (INPUT_WINDOW_LEFT_CONTEXT + INPUT_WINDOW_RIGHT_CONTEXT);
    int             SLIDING_WINDOW_OFFSET      = INPUT_WINDOW_INNER_CONTEXT * MFCC_WINDOW_STRIDE;


    MfccParams mfccParams(SAMP_FREQ, NUM_FBANK_BIN,
            MEL_LO_FREQ, MEL_HI_FREQ, NUM_MFCC_FEATS, FRAME_LEN_SAMPLES, false, NUM_MFCC_VECTORS);

    MFCC mfccInst = MFCC(mfccParams);

    Preprocess preprocessor(MFCC_WINDOW_LEN, MFCC_WINDOW_STRIDE, mfccInst);

    bool isFirstWindow = true;
    std::string currentRContext  = "";

    std::map <std::string, std::string> options;

    int result = ParseOptions(options, CMD_OPTIONS, argv, argc);
    if (result != 0)
    {
        return result;
    }

    // Create the network options
    common::PipelineOptions pipelineOptions;
    pipelineOptions.m_ModelFilePath = GetSpecifiedOption(options, MODEL_FILE_PATH);

    if (CheckOptionSpecified(options, PREFERRED_BACKENDS))
    {
        pipelineOptions.m_backends = GetPreferredBackendList((GetSpecifiedOption(options, PREFERRED_BACKENDS)));
    }
    else
    {
        pipelineOptions.m_backends = {"CpuAcc", "CpuRef"};
    }

    asr::IPipelinePtr asrPipeline = asr::CreatePipeline(pipelineOptions, labels);

    asr::AudioCapture capture;
    std::vector<float> audioData = capture.LoadAudioFile(GetSpecifiedOption(options, AUDIO_FILE_PATH));
    capture.InitSlidingWindow(audioData.data(), audioData.size(), SAMPLES_PER_INFERENCE, SLIDING_WINDOW_OFFSET);

    while (capture.HasNext())
    {
        std::vector<float> audioBlock = capture.Next();
        InferenceResults results;

        std::vector<int8_t> preprocessedData = asrPipeline->PreProcessing<float, int8_t>(audioBlock, preprocessor);
        asrPipeline->Inference<int8_t>(preprocessedData, results);
        asrPipeline->PostProcessing<int8_t>(results, isFirstWindow, !capture.HasNext(), currentRContext);
    }

    return 0;
}