MLECO-2079 Adding the C++ KWS example

Signed-off-by: Eanna O Cathain <eanna.ocathain@arm.com>
Change-Id: I81899bbfaada32f478c2e2fc6441eabb94d8d0fc
diff --git a/samples/common/test/Audio/AudioCaptureTest.cpp b/samples/common/test/Audio/AudioCaptureTest.cpp
new file mode 100644
index 0000000..b8ea7b2
--- /dev/null
+++ b/samples/common/test/Audio/AudioCaptureTest.cpp
@@ -0,0 +1,61 @@
+//
+// Copyright © 2021 Arm Ltd and Contributors. All rights reserved.
+// SPDX-License-Identifier: MIT
+//
+
+#define CATCH_CONFIG_MAIN
+#include <catch.hpp>
+#include <limits>
+
+#include "AudioCapture.hpp"
+
+TEST_CASE("Test capture of audio file")
+{
+    std::string testResources = TEST_RESOURCE_DIR;
+    REQUIRE(testResources != "");
+    std::string file =  testResources + "/" + "myVoiceIsMyPassportVerifyMe04.wav";
+    audio::AudioCapture capture;
+    std::vector<float> audioData = capture.LoadAudioFile(file);
+    capture.InitSlidingWindow(audioData.data(), audioData.size(), 47712, 16000);
+
+    std::vector<float> firstAudioBlock = capture.Next();
+    float actual1 = firstAudioBlock.at(0);
+    float actual2 = firstAudioBlock.at(47000);
+    CHECK(std::to_string(actual1) == "0.000352");
+    CHECK(std::to_string(actual2) == "-0.056441");
+    CHECK(firstAudioBlock.size() == 47712);
+
+    CHECK(capture.HasNext() == true);
+
+    std::vector<float> secondAudioBlock = capture.Next();
+    float actual3 = secondAudioBlock.at(0);
+    float actual4 = secondAudioBlock.at(47000);
+    CHECK(std::to_string(actual3) == "0.102077");
+    CHECK(std::to_string(actual4) == "0.000194");
+    CHECK(capture.HasNext() == true);
+
+    std::vector<float> thirdAudioBlock = capture.Next();
+    float actual5 = thirdAudioBlock.at(0);
+    float actual6 = thirdAudioBlock.at(33500);
+    float actual7 = thirdAudioBlock.at(33600);
+    CHECK(std::to_string(actual5) == "-0.076416");
+    CHECK(std::to_string(actual6) == "-0.000275");
+    CHECK(std::to_string(actual7) == "0.000000");
+    CHECK(capture.HasNext() == false);
+}
+
+TEST_CASE("Test sliding window of audio capture")
+{
+    std::string testResources = TEST_RESOURCE_DIR;
+    REQUIRE(testResources != "");
+    std::string file =  testResources + "/" + "myVoiceIsMyPassportVerifyMe04.wav";
+    audio::AudioCapture capture;
+    std::vector<float> audioData = capture.LoadAudioFile(file);
+    capture.InitSlidingWindow(audioData.data(), audioData.size(), 47712, 16000);
+    capture.Next();
+    capture.Next();
+
+    CHECK(capture.HasNext() == true);
+    capture.Next();
+    CHECK(capture.HasNext() == false);
+}
diff --git a/samples/common/test/Audio/MathUtilsTest.cpp b/samples/common/test/Audio/MathUtilsTest.cpp
new file mode 100644
index 0000000..d7a435d
--- /dev/null
+++ b/samples/common/test/Audio/MathUtilsTest.cpp
@@ -0,0 +1,112 @@
+//
+// Copyright © 2021 Arm Ltd and Contributors. All rights reserved.
+// SPDX-License-Identifier: MIT
+//
+
+#include <catch.hpp>
+#include <limits>
+
+#include "MathUtils.hpp"
+#include <iostream>
+#include <numeric>
+
+TEST_CASE("Test DotProductF32")
+{
+    // Test  Constants:
+    const int length = 6;
+
+    float inputA[] = { 1, 1, 1, 0, 0, 0 };
+    float inputB[] = { 0, 0, 0, 1, 1, 1 };
+
+    float dot_prod = MathUtils::DotProductF32(inputA, inputB, length);
+    float expectedResult = 0;
+    CHECK(dot_prod == expectedResult);
+}
+
+TEST_CASE("Test FFT32")
+{
+    // Test  Constants:
+    std::vector<float> input(32, 0);
+    std::vector<float> output(32);
+    std::vector<float> expectedResult(32, 0);
+
+    MathUtils::FftF32(input, output);
+
+    // To avoid common failed assertions due to rounding of near-zero values a small offset is added
+    transform(output.begin(), output.end(), output.begin(),
+    bind2nd(std::plus<double>(), 0.1));
+
+    transform(expectedResult.begin(), expectedResult.end(), expectedResult.begin(),
+    bind2nd(std::plus<double>(), 0.1));
+
+    for (int i = 0; i < output.size(); i++)
+    {
+        CHECK (expectedResult[i] == Approx(output[i]));
+    }
+}
+
+TEST_CASE("Test ComplexMagnitudeSquaredF32")
+{
+    // Test  Constants:
+    float input[] = { 0.0, 0.0, 0.5, 0.5,1,1 };
+    int inputLen = (sizeof(input)/sizeof(*input));
+    float expectedResult[] = { 0.0, 0.5, 2 };
+    int outputLen = inputLen/2;
+    float output[outputLen];
+
+    MathUtils::ComplexMagnitudeSquaredF32(input, inputLen, output, outputLen);
+
+    for (int i = 0; i < outputLen; i++)
+    {
+        CHECK (expectedResult[i] == Approx(output[i]));
+    }
+}
+
+TEST_CASE("Test VecLogarithmF32")
+{
+    // Test  Constants:
+
+    std::vector<float> input = { 1, 0.1e-10 };
+    std::vector<float> expectedResult = { 0, -25.328436 };
+    std::vector<float> output(input.size());
+    MathUtils::VecLogarithmF32(input,output);
+
+    for (int i = 0; i < input.size(); i++)
+    {
+        CHECK (expectedResult[i] == Approx(output[i]));
+    }
+}
+
+TEST_CASE("Test MeanF32")
+{    
+    // Test  Constants:
+    float input[] = { 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 1.000 };
+    uint32_t inputLen = (sizeof(input)/sizeof(*input));
+    float output;
+
+    // Manually calculated mean of above array
+    float expectedResult = 0.100;
+    output = MathUtils::MeanF32(input, inputLen);
+
+    CHECK (expectedResult == Approx(output));
+}
+
+TEST_CASE("Test StdDevF32")
+{
+    // Test  Constants:
+
+    float input[] = { 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 1.000 };
+
+    uint32_t inputLen = (sizeof(input)/sizeof(*input));
+
+    // Calculate mean using std library to avoid dependency on MathUtils::MeanF32 
+    float mean = (std::accumulate(input, input + inputLen, 0.0f))/float(inputLen);
+
+    float output = MathUtils::StdDevF32(input, inputLen, mean);
+
+    // Manually calculated standard deviation of above array
+    float expectedResult = 0.300;
+
+    CHECK (expectedResult == Approx(output));
+}
+