1 files changed, 93 insertions, 0 deletions
diff --git a/third_party/libwebrtc/rtc_tools/frame_analyzer/linear_least_squares_unittest.cc b/third_party/libwebrtc/rtc_tools/frame_analyzer/linear_least_squares_unittest.cc
new file mode 100644
index 0000000000..d4a23e87a6
--- /dev/null
+++ b/third_party/libwebrtc/rtc_tools/frame_analyzer/linear_least_squares_unittest.cc
@@ -0,0 +1,93 @@
+/*
+ *  Copyright (c) 2018 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 "rtc_tools/frame_analyzer/linear_least_squares.h"
+
+#include <cstdint>
+
+#include "test/gtest.h"
+
+namespace webrtc {
+namespace test {
+
+TEST(LinearLeastSquares, ScalarIdentityOneObservation) {
+  IncrementalLinearLeastSquares lls;
+  lls.AddObservations({{1}}, {{1}});
+  EXPECT_EQ(std::vector<std::vector<double>>({{1.0}}), lls.GetBestSolution());
+}
+
+TEST(LinearLeastSquares, ScalarIdentityTwoObservationsOneCall) {
+  IncrementalLinearLeastSquares lls;
+  lls.AddObservations({{1, 2}}, {{1, 2}});
+  EXPECT_EQ(std::vector<std::vector<double>>({{1.0}}), lls.GetBestSolution());
+}
+
+TEST(LinearLeastSquares, ScalarIdentityTwoObservationsTwoCalls) {
+  IncrementalLinearLeastSquares lls;
+  lls.AddObservations({{1}}, {{1}});
+  lls.AddObservations({{2}}, {{2}});
+  EXPECT_EQ(std::vector<std::vector<double>>({{1.0}}), lls.GetBestSolution());
+}
+
+TEST(LinearLeastSquares, MatrixIdentityOneObservation) {
+  IncrementalLinearLeastSquares lls;
+  lls.AddObservations({{1, 2}, {3, 4}}, {{1, 2}, {3, 4}});
+  EXPECT_EQ(std::vector<std::vector<double>>({{1.0, 0.0}, {0.0, 1.0}}),
+            lls.GetBestSolution());
+}
+
+TEST(LinearLeastSquares, MatrixManyObservations) {
+  IncrementalLinearLeastSquares lls;
+  // Test that we can find the solution of the overspecified equation system:
+  // [1, 2] [1, 3] = [5,  11]
+  // [3, 4] [2, 4]   [11, 25]
+  // [5, 6]          [17, 39]
+  lls.AddObservations({{1}, {2}}, {{5}, {11}});
+  lls.AddObservations({{3}, {4}}, {{11}, {25}});
+  lls.AddObservations({{5}, {6}}, {{17}, {39}});
+
+  const std::vector<std::vector<double>> result = lls.GetBestSolution();
+  // We allow some numerical flexibility here.
+  EXPECT_DOUBLE_EQ(1.0, result[0][0]);
+  EXPECT_DOUBLE_EQ(2.0, result[0][1]);
+  EXPECT_DOUBLE_EQ(3.0, result[1][0]);
+  EXPECT_DOUBLE_EQ(4.0, result[1][1]);
+}
+
+TEST(LinearLeastSquares, MatrixVectorOneObservation) {
+  IncrementalLinearLeastSquares lls;
+  // Test that we can find the solution of the overspecified equation system:
+  // [1, 2] [1] = [5]
+  // [3, 4] [2]   [11]
+  // [5, 6]       [17]
+  lls.AddObservations({{1, 3, 5}, {2, 4, 6}}, {{5, 11, 17}});
+
+  const std::vector<std::vector<double>> result = lls.GetBestSolution();
+  // We allow some numerical flexibility here.
+  EXPECT_DOUBLE_EQ(1.0, result[0][0]);
+  EXPECT_DOUBLE_EQ(2.0, result[0][1]);
+}
+
+TEST(LinearLeastSquares, LinearLeastSquaresNonPerfectSolution) {
+  IncrementalLinearLeastSquares lls;
+  // Test that we can find the non-perfect solution of the overspecified
+  // equation system:
+  // [1] [20] = [21]
+  // [2]        [39]
+  // [3]        [60]
+  // [2]        [41]
+  // [1]        [19]
+  lls.AddObservations({{1, 2, 3, 2, 1}}, {{21, 39, 60, 41, 19}});
+
+  EXPECT_DOUBLE_EQ(20.0, lls.GetBestSolution()[0][0]);
+}
+
+}  // namespace test
+}  // namespace webrtc