Opensource ML embedded evaluation kit

Change-Id: I12e807f19f5cacad7cef82572b6dd48252fd61fd
diff --git a/source/use_case/kws/src/UseCaseHandler.cc b/source/use_case/kws/src/UseCaseHandler.cc
new file mode 100644
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+++ b/source/use_case/kws/src/UseCaseHandler.cc
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+/*
+ * Copyright (c) 2021 Arm Limited. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include "UseCaseHandler.hpp"
+
+#include "InputFiles.hpp"
+#include "Classifier.hpp"
+#include "DsCnnModel.hpp"
+#include "hal.h"
+#include "DsCnnMfcc.hpp"
+#include "AudioUtils.hpp"
+#include "UseCaseCommonUtils.hpp"
+#include "KwsResult.hpp"
+
+#include <vector>
+#include <functional>
+
+using KwsClassifier = arm::app::Classifier;
+
+namespace arm {
+namespace app {
+
+    /**
+    * @brief            Helper function to increment current audio clip index.
+    * @param[in,out]    ctx   Pointer to the application context object.
+    **/
+    static void _IncrementAppCtxClipIdx(ApplicationContext& ctx);
+
+    /**
+     * @brief           Helper function to set the audio clip index.
+     * @param[in,out]   ctx   Pointer to the application context object.
+     * @param[in]       idx   Value to be set.
+     * @return          true if index is set, false otherwise.
+     **/
+    static bool _SetAppCtxClipIdx(ApplicationContext& ctx, uint32_t idx);
+
+    /**
+     * @brief           Presents inference results using the data presentation
+     *                  object.
+     * @param[in]       platform    Reference to the hal platform object.
+     * @param[in]       results     Vector of classification results to be displayed.
+     * @param[in]       infTimeMs   Inference time in milliseconds, if available,
+     *                              otherwise, this can be passed in as 0.
+     * @return          true if successful, false otherwise.
+     **/
+    static bool _PresentInferenceResult(hal_platform& platform,
+                                        const std::vector<arm::app::kws::KwsResult>& results);
+
+    /**
+     * @brief Returns a function to perform feature calculation and populates input tensor data with
+     * MFCC data.
+     *
+     * Input tensor data type check is performed to choose correct MFCC feature data type.
+     * If tensor has an integer data type then original features are quantised.
+     *
+     * Warning: MFCC calculator provided as input must have the same life scope as returned function.
+     *
+     * @param[in]       mfcc          MFCC feature calculator.
+     * @param[in,out]   inputTensor   Input tensor pointer to store calculated features.
+     * @param[in]       cacheSize     Size of the feature vectors cache (number of feature vectors).
+     * @return          Function to be called providing audio sample and sliding window index.
+     */
+    static std::function<void (std::vector<int16_t>&, int, bool, size_t)>
+            GetFeatureCalculator(audio::DsCnnMFCC&  mfcc,
+                                 TfLiteTensor*      inputTensor,
+                                 size_t             cacheSize);
+
+    /* Audio inference handler. */
+    bool ClassifyAudioHandler(ApplicationContext& ctx, uint32_t clipIndex, bool runAll)
+    {
+        auto& platform = ctx.Get<hal_platform&>("platform");
+
+        constexpr uint32_t dataPsnTxtInfStartX = 20;
+        constexpr uint32_t dataPsnTxtInfStartY = 40;
+        constexpr int minTensorDims = static_cast<int>(
+            (arm::app::DsCnnModel::ms_inputRowsIdx > arm::app::DsCnnModel::ms_inputColsIdx)?
+             arm::app::DsCnnModel::ms_inputRowsIdx : arm::app::DsCnnModel::ms_inputColsIdx);
+
+        platform.data_psn->clear(COLOR_BLACK);
+
+        auto& model = ctx.Get<Model&>("model");
+
+        /* If the request has a valid size, set the audio index. */
+        if (clipIndex < NUMBER_OF_FILES) {
+            if (!_SetAppCtxClipIdx(ctx, clipIndex)) {
+                return false;
+            }
+        }
+        if (!model.IsInited()) {
+            printf_err("Model is not initialised! Terminating processing.\n");
+            return false;
+        }
+
+        const auto frameLength = ctx.Get<int>("frameLength");
+        const auto frameStride = ctx.Get<int>("frameStride");
+        const auto scoreThreshold = ctx.Get<float>("scoreThreshold");
+        auto startClipIdx = ctx.Get<uint32_t>("clipIndex");
+
+        TfLiteTensor* outputTensor = model.GetOutputTensor(0);
+        TfLiteTensor* inputTensor = model.GetInputTensor(0);
+
+        if (!inputTensor->dims) {
+            printf_err("Invalid input tensor dims\n");
+            return false;
+        } else if (inputTensor->dims->size < minTensorDims) {
+            printf_err("Input tensor dimension should be >= %d\n", minTensorDims);
+            return false;
+        }
+
+        TfLiteIntArray* inputShape = model.GetInputShape(0);
+        const uint32_t kNumCols = inputShape->data[arm::app::DsCnnModel::ms_inputColsIdx];
+        const uint32_t kNumRows = inputShape->data[arm::app::DsCnnModel::ms_inputRowsIdx];
+
+        audio::DsCnnMFCC mfcc = audio::DsCnnMFCC(kNumCols, frameLength);
+        mfcc.Init();
+
+        /* Deduce the data length required for 1 inference from the network parameters. */
+        auto audioDataWindowSize = kNumRows * frameStride + (frameLength - frameStride);
+        auto mfccWindowSize = frameLength;
+        auto mfccWindowStride = frameStride;
+
+        /* We choose to move by half the window size => for a 1 second window size
+         * there is an overlap of 0.5 seconds. */
+        auto audioDataStride = audioDataWindowSize / 2;
+
+        /* To have the previously calculated features re-usable, stride must be multiple
+         * of MFCC features window stride. */
+        if (0 != audioDataStride % mfccWindowStride) {
+
+            /* Reduce the stride. */
+            audioDataStride -= audioDataStride % mfccWindowStride;
+        }
+
+        auto nMfccVectorsInAudioStride = audioDataStride/mfccWindowStride;
+
+        /* We expect to be sampling 1 second worth of data at a time.
+         * NOTE: This is only used for time stamp calculation. */
+        const float secondsPerSample = 1.0/audio::DsCnnMFCC::ms_defaultSamplingFreq;
+
+        do {
+            auto currentIndex = ctx.Get<uint32_t>("clipIndex");
+
+            /* Creating a mfcc features sliding window for the data required for 1 inference. */
+            auto audioMFCCWindowSlider = audio::SlidingWindow<const int16_t>(
+                                            get_audio_array(currentIndex),
+                                            audioDataWindowSize, mfccWindowSize,
+                                            mfccWindowStride);
+
+            /* Creating a sliding window through the whole audio clip. */
+            auto audioDataSlider = audio::SlidingWindow<const int16_t>(
+                                        get_audio_array(currentIndex),
+                                        get_audio_array_size(currentIndex),
+                                        audioDataWindowSize, audioDataStride);
+
+            /* Calculate number of the feature vectors in the window overlap region.
+             * These feature vectors will be reused.*/
+            auto numberOfReusedFeatureVectors = audioMFCCWindowSlider.TotalStrides() + 1
+                                                - nMfccVectorsInAudioStride;
+
+            /* Construct feature calculation function. */
+            auto mfccFeatureCalc = GetFeatureCalculator(mfcc, inputTensor,
+                                                        numberOfReusedFeatureVectors);
+
+            if (!mfccFeatureCalc){
+                return false;
+            }
+
+            /* Declare a container for results. */
+            std::vector<arm::app::kws::KwsResult> results;
+
+            /* Display message on the LCD - inference running. */
+            std::string str_inf{"Running inference... "};
+            platform.data_psn->present_data_text(
+                                str_inf.c_str(), str_inf.size(),
+                                dataPsnTxtInfStartX, dataPsnTxtInfStartY, 0);
+            info("Running inference on audio clip %u => %s\n", currentIndex,
+                 get_filename(currentIndex));
+
+            /* Start sliding through audio clip. */
+            while (audioDataSlider.HasNext()) {
+                const int16_t *inferenceWindow = audioDataSlider.Next();
+
+                /* We moved to the next window - set the features sliding to the new address. */
+                audioMFCCWindowSlider.Reset(inferenceWindow);
+
+                /* The first window does not have cache ready. */
+                bool useCache = audioDataSlider.Index() > 0 && numberOfReusedFeatureVectors > 0;
+
+                /* Start calculating features inside one audio sliding window. */
+                while (audioMFCCWindowSlider.HasNext()) {
+                    const int16_t *mfccWindow = audioMFCCWindowSlider.Next();
+                    std::vector<int16_t> mfccAudioData = std::vector<int16_t>(mfccWindow,
+                                                            mfccWindow + mfccWindowSize);
+                    /* Compute features for this window and write them to input tensor. */
+                    mfccFeatureCalc(mfccAudioData,
+                                    audioMFCCWindowSlider.Index(),
+                                    useCache,
+                                    nMfccVectorsInAudioStride);
+                }
+
+                info("Inference %zu/%zu\n", audioDataSlider.Index() + 1,
+                     audioDataSlider.TotalStrides() + 1);
+
+                /* Run inference over this audio clip sliding window. */
+                arm::app::RunInference(platform, model);
+
+                std::vector<ClassificationResult> classificationResult;
+                auto& classifier = ctx.Get<KwsClassifier&>("classifier");
+                classifier.GetClassificationResults(outputTensor, classificationResult,
+                                                    ctx.Get<std::vector<std::string>&>("labels"), 1);
+
+                results.emplace_back(kws::KwsResult(classificationResult,
+                    audioDataSlider.Index() * secondsPerSample * audioDataStride,
+                    audioDataSlider.Index(), scoreThreshold));
+
+#if VERIFY_TEST_OUTPUT
+                arm::app::DumpTensor(outputTensor);
+#endif /* VERIFY_TEST_OUTPUT */
+            } /* while (audioDataSlider.HasNext()) */
+
+            /* Erase. */
+            str_inf = std::string(str_inf.size(), ' ');
+            platform.data_psn->present_data_text(
+                                str_inf.c_str(), str_inf.size(),
+                                dataPsnTxtInfStartX, dataPsnTxtInfStartY, false);
+
+            ctx.Set<std::vector<arm::app::kws::KwsResult>>("results", results);
+
+            if (!_PresentInferenceResult(platform, results)) {
+                return false;
+            }
+
+            _IncrementAppCtxClipIdx(ctx);
+
+        } while (runAll && ctx.Get<uint32_t>("clipIndex") != startClipIdx);
+
+        return true;
+    }
+
+    static void _IncrementAppCtxClipIdx(ApplicationContext& ctx)
+    {
+        auto curAudioIdx = ctx.Get<uint32_t>("clipIndex");
+
+        if (curAudioIdx + 1 >= NUMBER_OF_FILES) {
+            ctx.Set<uint32_t>("clipIndex", 0);
+            return;
+        }
+        ++curAudioIdx;
+        ctx.Set<uint32_t>("clipIndex", curAudioIdx);
+    }
+
+    static bool _SetAppCtxClipIdx(ApplicationContext& ctx, const uint32_t idx)
+    {
+        if (idx >= NUMBER_OF_FILES) {
+            printf_err("Invalid idx %u (expected less than %u)\n",
+                       idx, NUMBER_OF_FILES);
+            return false;
+        }
+        ctx.Set<uint32_t>("clipIndex", idx);
+        return true;
+    }
+
+    static bool _PresentInferenceResult(hal_platform& platform,
+                                        const std::vector<arm::app::kws::KwsResult>& results)
+    {
+        constexpr uint32_t dataPsnTxtStartX1 = 20;
+        constexpr uint32_t dataPsnTxtStartY1 = 30;
+        constexpr uint32_t dataPsnTxtYIncr   = 16;  /* Row index increment. */
+
+        platform.data_psn->set_text_color(COLOR_GREEN);
+
+        /* Display each result */
+        uint32_t rowIdx1 = dataPsnTxtStartY1 + 2 * dataPsnTxtYIncr;
+
+        for (uint32_t i = 0; i < results.size(); ++i) {
+
+            std::string topKeyword{"<none>"};
+            float score = 0.f;
+
+            if (results[i].m_resultVec.size()) {
+                topKeyword = results[i].m_resultVec[0].m_label;
+                score = results[i].m_resultVec[0].m_normalisedVal;
+            }
+
+            std::string resultStr =
+                std::string{"@"} + std::to_string(results[i].m_timeStamp) +
+                std::string{"s: "} + topKeyword + std::string{" ("} +
+                std::to_string(static_cast<int>(score * 100)) + std::string{"%)"};
+
+            platform.data_psn->present_data_text(
+                                    resultStr.c_str(), resultStr.size(),
+                                    dataPsnTxtStartX1, rowIdx1, false);
+            rowIdx1 += dataPsnTxtYIncr;
+
+            info("For timestamp: %f (inference #: %u); threshold: %f\n",
+                    results[i].m_timeStamp, results[i].m_inferenceNumber,
+                    results[i].m_threshold);
+            for (uint32_t j = 0; j < results[i].m_resultVec.size(); ++j) {
+                info("\t\tlabel @ %u: %s, score: %f\n", j,
+                    results[i].m_resultVec[j].m_label.c_str(),
+                    results[i].m_resultVec[j].m_normalisedVal);
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * @brief Generic feature calculator factory.
+     *
+     * Returns lambda function to compute features using features cache.
+     * Real features math is done by a lambda function provided as a parameter.
+     * Features are written to input tensor memory.
+     *
+     * @tparam T            Feature vector type.
+     * @param inputTensor   Model input tensor pointer.
+     * @param cacheSize     Number of feature vectors to cache. Defined by the sliding window overlap.
+     * @param compute       Features calculator function.
+     * @return              Lambda function to compute features.
+     */
+    template<class T>
+    std::function<void (std::vector<int16_t>&, size_t, bool, size_t)>
+    _FeatureCalc(TfLiteTensor* inputTensor, size_t cacheSize,
+                 std::function<std::vector<T> (std::vector<int16_t>& )> compute)
+    {
+        /* Feature cache to be captured by lambda function. */
+        static std::vector<std::vector<T>> featureCache = std::vector<std::vector<T>>(cacheSize);
+
+        return [=](std::vector<int16_t>& audioDataWindow,
+                                     size_t index,
+                                     bool useCache,
+                                     size_t featuresOverlapIndex)
+        {
+            T *tensorData = tflite::GetTensorData<T>(inputTensor);
+            std::vector<T> features;
+
+            /* Reuse features from cache if cache is ready and sliding windows overlap.
+             * Overlap is in the beginning of sliding window with a size of a feature cache. */
+            if (useCache && index < featureCache.size()) {
+                features = std::move(featureCache[index]);
+            } else {
+                features = std::move(compute(audioDataWindow));
+            }
+            auto size = features.size();
+            auto sizeBytes = sizeof(T) * size;
+            std::memcpy(tensorData + (index * size), features.data(), sizeBytes);
+
+            /* Start renewing cache as soon iteration goes out of the windows overlap. */
+            if (index >= featuresOverlapIndex) {
+                featureCache[index - featuresOverlapIndex] = std::move(features);
+            }
+        };
+    }
+
+    template std::function<void (std::vector<int16_t>&, size_t , bool, size_t)>
+        _FeatureCalc<int8_t>(TfLiteTensor* inputTensor,
+                            size_t cacheSize,
+                            std::function<std::vector<int8_t> (std::vector<int16_t>& )> compute);
+
+    template std::function<void (std::vector<int16_t>&, size_t , bool, size_t)>
+        _FeatureCalc<uint8_t>(TfLiteTensor* inputTensor,
+                              size_t cacheSize,
+                              std::function<std::vector<uint8_t> (std::vector<int16_t>& )> compute);
+
+    template std::function<void (std::vector<int16_t>&, size_t , bool, size_t)>
+        _FeatureCalc<int16_t>(TfLiteTensor* inputTensor,
+                              size_t cacheSize,
+                              std::function<std::vector<int16_t> (std::vector<int16_t>& )> compute);
+
+    template std::function<void(std::vector<int16_t>&, size_t, bool, size_t)>
+        _FeatureCalc<float>(TfLiteTensor *inputTensor,
+                            size_t cacheSize,
+                            std::function<std::vector<float>(std::vector<int16_t>&)> compute);
+
+
+    static std::function<void (std::vector<int16_t>&, int, bool, size_t)>
+    GetFeatureCalculator(audio::DsCnnMFCC& mfcc, TfLiteTensor* inputTensor, size_t cacheSize)
+    {
+        std::function<void (std::vector<int16_t>&, size_t, bool, size_t)> mfccFeatureCalc;
+
+        TfLiteQuantization quant = inputTensor->quantization;
+
+        if (kTfLiteAffineQuantization == quant.type) {
+
+            auto *quantParams = (TfLiteAffineQuantization *) quant.params;
+            const float quantScale = quantParams->scale->data[0];
+            const int quantOffset = quantParams->zero_point->data[0];
+
+            switch (inputTensor->type) {
+                case kTfLiteInt8: {
+                    mfccFeatureCalc = _FeatureCalc<int8_t>(inputTensor,
+                                                           cacheSize,
+                                                           [=, &mfcc](std::vector<int16_t>& audioDataWindow) {
+                                                               return mfcc.MfccComputeQuant<int8_t>(audioDataWindow,
+                                                                                                    quantScale,
+                                                                                                    quantOffset);
+                                                           }
+                    );
+                    break;
+                }
+                case kTfLiteUInt8: {
+                    mfccFeatureCalc = _FeatureCalc<uint8_t>(inputTensor,
+                                                            cacheSize,
+                                                           [=, &mfcc](std::vector<int16_t>& audioDataWindow) {
+                                                               return mfcc.MfccComputeQuant<uint8_t>(audioDataWindow,
+                                                                                                     quantScale,
+                                                                                                     quantOffset);
+                                                           }
+                    );
+                    break;
+                }
+                case kTfLiteInt16: {
+                    mfccFeatureCalc = _FeatureCalc<int16_t>(inputTensor,
+                                                            cacheSize,
+                                                            [=, &mfcc](std::vector<int16_t>& audioDataWindow) {
+                                                                return mfcc.MfccComputeQuant<int16_t>(audioDataWindow,
+                                                                                                      quantScale,
+                                                                                                      quantOffset);
+                                                            }
+                    );
+                    break;
+                }
+                default:
+                    printf_err("Tensor type %s not supported\n", TfLiteTypeGetName(inputTensor->type));
+            }
+
+
+        } else {
+            mfccFeatureCalc = mfccFeatureCalc = _FeatureCalc<float>(inputTensor,
+                                                                    cacheSize,
+                                                                    [&mfcc](std::vector<int16_t>& audioDataWindow) {
+                                                                        return mfcc.MfccCompute(audioDataWindow);
+                                                                    });
+        }
+        return mfccFeatureCalc;
+    }
+
+} /* namespace app */
+} /* namespace arm */
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