chromium/third_party/tflite/src/tensorflow/lite/kernels/mfcc.cc

/* Copyright 2018 The TensorFlow Authors. All Rights Reserved.

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 "tensorflow/lite/kernels/internal/mfcc.h"

#include <stddef.h>
#include <stdint.h>

#include <vector>

#include "flatbuffers/flexbuffers.h"  // from @flatbuffers
#include "tensorflow/lite/core/c/common.h"
#include "tensorflow/lite/kernels/internal/compatibility.h"
#include "tensorflow/lite/kernels/internal/mfcc_dct.h"
#include "tensorflow/lite/kernels/internal/mfcc_mel_filterbank.h"
#include "tensorflow/lite/kernels/internal/optimized/optimized_ops.h"
#include "tensorflow/lite/kernels/internal/reference/reference_ops.h"
#include "tensorflow/lite/kernels/internal/tensor.h"
#include "tensorflow/lite/kernels/internal/tensor_ctypes.h"
#include "tensorflow/lite/kernels/kernel_util.h"

namespace tflite {
namespace ops {
namespace custom {
namespace mfcc {

enum KernelType { … };

TfLiteMfccParams;

constexpr int kInputTensorWav = …;
constexpr int kInputTensorRate = …;
constexpr int kOutputTensor = …;

void* Init(TfLiteContext* context, const char* buffer, size_t length) { … }

void Free(TfLiteContext* context, void* buffer) { … }

TfLiteStatus Prepare(TfLiteContext* context, TfLiteNode* node) { … }

// Input is a single squared-magnitude spectrogram frame. The input spectrum
// is converted to linear magnitude and weighted into bands using a
// triangular mel filterbank, and a discrete cosine transform (DCT) of the
// values is taken. Output is populated with the lowest dct_coefficient_count
// of these values.
template <KernelType kernel_type>
TfLiteStatus Eval(TfLiteContext* context, TfLiteNode* node) { … }

}  // namespace mfcc

TfLiteRegistration* Register_MFCC() { … }

}  // namespace custom
}  // namespace ops
}  // namespace tflite