MLECO-3183: Refactoring application sources

Platform agnostic application sources are moved into application
api module with their own independent CMake projects.

Changes for MLECO-3080 also included - they create CMake projects
individial API's (again, platform agnostic) that dependent on the
common logic. The API for KWS_API "joint" API has been removed and
now the use case relies on individual KWS, and ASR API libraries.

Change-Id: I1f7748dc767abb3904634a04e0991b74ac7b756d
Signed-off-by: Kshitij Sisodia <kshitij.sisodia@arm.com>

1 files changed, 97 insertions, 0 deletions

diff --git a/source/application/api/use_case/ad/include/AdMelSpectrogram.hpp b/source/application/api/use_case/ad/include/AdMelSpectrogram.hpp
new file mode 100644
index 0000000..05c5bfc
--- /dev/null
+++ b/source/application/api/use_case/ad/include/AdMelSpectrogram.hpp
@@ -0,0 +1,97 @@
+/*
+ * 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.
+ */
+#ifndef ADMELSPECTROGRAM_HPP
+#define ADMELSPECTROGRAM_HPP
+
+#include "MelSpectrogram.hpp"
+
+namespace arm {
+namespace app {
+namespace audio {
+
+    /* Class to provide anomaly detection specific Mel Spectrogram calculation requirements */
+    class AdMelSpectrogram : public MelSpectrogram {
+
+    public:
+        static constexpr uint32_t  ms_defaultSamplingFreq = 16000;
+        static constexpr uint32_t  ms_defaultNumFbankBins =    64;
+        static constexpr uint32_t  ms_defaultMelLoFreq    =     0;
+        static constexpr uint32_t  ms_defaultMelHiFreq    =  8000;
+        static constexpr bool      ms_defaultUseHtkMethod = false;
+
+        explicit AdMelSpectrogram(const size_t frameLen)
+                :  MelSpectrogram(MelSpecParams(
+                ms_defaultSamplingFreq, ms_defaultNumFbankBins,
+                ms_defaultMelLoFreq, ms_defaultMelHiFreq,
+                frameLen, ms_defaultUseHtkMethod))
+        {}
+
+        AdMelSpectrogram()  = delete;
+        ~AdMelSpectrogram() = default;
+
+    protected:
+
+        /**
+         * @brief       Overrides base class implementation of this function.
+         * @param[in]   fftVec                  Vector populated with FFT magnitudes
+         * @param[in]   melFilterBank           2D Vector with filter bank weights
+         * @param[in]   filterBankFilterFirst   Vector containing the first indices of filter bank
+         *                                      to be used for each bin.
+         * @param[in]   filterBankFilterLast    Vector containing the last indices of filter bank
+         *                                      to be used for each bin.
+         * @param[out]  melEnergies             Pre-allocated vector of MEL energies to be
+         *                                      populated.
+         * @return      true if successful, false otherwise
+         */
+        virtual bool ApplyMelFilterBank(
+                std::vector<float>&                 fftVec,
+                std::vector<std::vector<float>>&    melFilterBank,
+                std::vector<uint32_t>&               filterBankFilterFirst,
+                std::vector<uint32_t>&               filterBankFilterLast,
+                std::vector<float>&                 melEnergies) override;
+
+        /**
+         * @brief       Override for the base class implementation convert mel
+         *              energies to logarithmic scale. The difference from
+         *              default behaviour is that the power is converted to dB
+         *              and subsequently clamped.
+         * @param[in,out]   melEnergies - 1D vector of Mel energies
+         **/
+        virtual void ConvertToLogarithmicScale(std::vector<float>& melEnergies) override;
+
+        /**
+         * @brief       Given the low and high Mel values, get the normaliser
+         *              for weights to be applied when populating the filter
+         *              bank. Override for the base class implementation.
+         * @param[in]   leftMel - low Mel frequency value
+         * @param[in]   rightMel - high Mel frequency value
+         * @param[in]   useHTKMethod - bool to signal if HTK method is to be
+         *              used for calculation
+         * @return      Return float value to be applied 
+         *              when populating the filter bank.
+         */
+        virtual float GetMelFilterBankNormaliser(
+                const float&   leftMel,
+                const float&   rightMel,
+                const bool     useHTKMethod) override;
+    };
+
+} /* namespace audio */
+} /* namespace app */
+} /* namespace arm */
+
+#endif /* ADMELSPECTROGRAM_HPP */