Make the nonlinear beamformer steerable

webrtc/modules/audio_processing/beamformer/nonlinear_beamformer_unittest.cc

Index: webrtc/modules/audio_processing/beamformer/nonlinear_beamformer_unittest.cc
diff --git a/webrtc/modules/audio_processing/beamformer/nonlinear_beamformer_unittest.cc b/webrtc/modules/audio_processing/beamformer/nonlinear_beamformer_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..c453045b6f3b4824667ea125098d78a26f0134aa
--- /dev/null
+++ b/webrtc/modules/audio_processing/beamformer/nonlinear_beamformer_unittest.cc
@@ -0,0 +1,58 @@
+/*
+ *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/modules/audio_processing/beamformer/nonlinear_beamformer.h"
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace webrtc {
+namespace {
+
+SphericalPointf AzimuthToPoint(float azimuth_radians) {
+  return SphericalPointf(azimuth_radians, 0.f, 1.f);
+}
+
+void Verify(NonlinearBeamformer* bf, float target_azimuth_radians) {
+  const float kHalfBeamWidthRadians = DegreesToRadians(20.f);
+  EXPECT_TRUE(bf->IsInBeam(AzimuthToPoint(target_azimuth_radians)));
+  EXPECT_TRUE(bf->IsInBeam(
+      AzimuthToPoint(target_azimuth_radians - kHalfBeamWidthRadians + 0.001f)));
+  EXPECT_TRUE(bf->IsInBeam(
+      AzimuthToPoint(target_azimuth_radians + kHalfBeamWidthRadians - 0.001f)));
+  EXPECT_FALSE(bf->IsInBeam(
+      AzimuthToPoint(target_azimuth_radians - kHalfBeamWidthRadians - 0.001f)));
+  EXPECT_FALSE(bf->IsInBeam(
+      AzimuthToPoint(target_azimuth_radians + kHalfBeamWidthRadians + 0.001f)));
+}
+
+void AimAndVerify(NonlinearBeamformer* bf, float target_azimuth_radians) {
+  bf->AimAt(AzimuthToPoint(target_azimuth_radians));
+  Verify(bf, target_azimuth_radians);
+}
+
+}  // namespace
+
+TEST(NonlinearBeamformerTest, AimingModifiesBeam) {

[Andrew MacDonald, 2015/10/21 03:27:43]

Can you add another test to verify non-x-axis-aligned arrays?

[aluebs-webrtc, 2015/10/27 18:08:16]

The array doesn't affect the steering. Just had to put some geometry for it to
run.

[Andrew MacDonald, 2015/10/28 01:57:56]

Got it.

+  const int kChunkSizeMs = 10;
+  const int kSampleRateHz = 16000;
+  std::vector<Point> array_geometry;
+  array_geometry.push_back(Point(-0.025f, 0.f, 0.f));
+  array_geometry.push_back(Point(0.025f, 0.f, 0.f));
+  NonlinearBeamformer bf(array_geometry);
+  bf.Initialize(kChunkSizeMs, kSampleRateHz);
+  // The default constructor parameter sets the target angle to PI / 2.
+  Verify(&bf, M_PI / 2.f);
+  AimAndVerify(&bf, M_PI / 3.f);
+  AimAndVerify(&bf, 3.f * M_PI / 4.f);
+  AimAndVerify(&bf, M_PI / 6.f);
+  AimAndVerify(&bf, M_PI);
+}
+
+}  // namespace webrtc