comparison carfac/sai_test.cc @ 642:20f64146c2ce

Initial translation of SAI code to C++.

This only implements the simple (as opposed to the layered) SAI, as
implemented in SAI_Run.m.

+// Copyright 2013, Google, Inc.
+// Author: Ron Weiss <[e-mail]>
+//
+// This C++ file is part of an implementation of Lyon's cochlear model:
+// "Cascade of Asymmetric Resonators with Fast-Acting Compression"
+// to supplement Lyon's upcoming book "Human and Machine Hearing"
+//
+// 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 "sai.h"
+
+#include <iostream>
+#include <vector>
+
+#include "gtest/gtest.h"
+
+using testing::Values;
+using std::vector;
+
+vector<FloatArray> CreateZeroSegment(int n_ch, int length) {
+  vector<FloatArray> segment;
+  for (int i = 0; i < length; ++i) {
+    segment.push_back(FloatArray::Zero(n_ch));
+  }
+  return segment;
+}
+
+bool HasPeakAt(const Float2dArray& frame, int index) {
+  if (index == 0) {
+    return frame(index) > frame(index + 1);
+  } else if (index == frame.size() - 1) {
+    return frame(index) > frame(index - 1);
+  }
+  return frame(index) > frame(index + 1) && frame(index) > frame(index - 1);
+}
+
+class SAIPeriodicInputTest
+    : public testing::TestWithParam<std::tr1::tuple<int, int>> {
+ protected:
+  void SetUp() {
+    period_ = std::tr1::get<0>(GetParam());
+    phase_ = std::tr1::get<1>(GetParam());
+  }
+
+  int period_;
+  int phase_;
+};
+
+TEST_P(SAIPeriodicInputTest, SingleChannelPulseTrain) {
+  vector<FloatArray> segment = CreateZeroSegment(1, 38);
+  for (int i = phase_; i < segment.size(); i += period_) {
+    segment[i](0) = 1;
+  }
+
+  SAIParams sai_params;
+  sai_params.window_width = segment.size();
+  sai_params.n_ch = 1;
+  sai_params.width = 15;
+  // Half of the SAI should come from the future.
+  // sai_params.future_lags = sai_params.width / 2;
+  sai_params.future_lags = 0;
+  sai_params.n_window_pos = 2;
+
+  SAI sai(sai_params);
+  Float2dArray sai_frame;
+  sai.RunSegment(segment, &sai_frame);
+
+  // The output should have peaks at the same positions, regardless of
+  // input phase.
+  for (int i = sai_frame.size() - 1; i >= 0 ; i -= period_) {
+    EXPECT_TRUE(HasPeakAt(sai_frame, i));
+  }
+
+  for (int i = 0; i < segment.size(); ++i) {
+    std::cout << segment[i](0) << " ";
+  }
+  std::cout << "\n";
+  for (int i = 0; i < sai_frame.size(); ++i) {
+    std::cout << sai_frame(i) << " ";
+  }
+  std::cout << "\n";
+}
+INSTANTIATE_TEST_CASE_P(PeriodicInputVariations, SAIPeriodicInputTest,
+                        testing::Combine(Values(25, 10, 5, 2),  // periods.
+                                         Values(0, 3)));  // phases.