diff --git a/services/surfaceflinger/Android.bp b/services/surfaceflinger/Android.bp
index 1007b3d..fb2cb0f 100644
--- a/services/surfaceflinger/Android.bp
+++ b/services/surfaceflinger/Android.bp
@@ -143,6 +143,7 @@
         "Scheduler/LayerHistory.cpp",
         "Scheduler/MessageQueue.cpp",
         "Scheduler/Scheduler.cpp",
+        "Scheduler/SchedulerUtils.cpp",
         "StartPropertySetThread.cpp",
         "SurfaceFlinger.cpp",
         "SurfaceInterceptor.cpp",
diff --git a/services/surfaceflinger/Scheduler/LayerHistory.cpp b/services/surfaceflinger/Scheduler/LayerHistory.cpp
index 1f47949..d5ccbe1 100644
--- a/services/surfaceflinger/Scheduler/LayerHistory.cpp
+++ b/services/surfaceflinger/Scheduler/LayerHistory.cpp
@@ -26,6 +26,8 @@
 #include <utils/Timers.h>
 #include <utils/Trace.h>
 
+#include "SchedulerUtils.h"
+
 namespace android {
 
 LayerHistory::LayerHistory() {}
@@ -38,7 +40,7 @@
 
 void LayerHistory::incrementCounter() {
     mCounter++;
-    mCounter = mCounter % ARRAY_SIZE;
+    mCounter = mCounter % scheduler::ARRAY_SIZE;
     // Clear all the previous data from the history. This is a ring buffer, so we are
     // reusing memory.
     mElements[mCounter].clear();
@@ -47,7 +49,8 @@
 const std::unordered_map<std::string, nsecs_t>& LayerHistory::get(size_t index) const {
     // For the purposes of the layer history, the index = 0 always needs to start at the
     // current counter, and then decrement to access the layers in correct historical order.
-    return mElements.at((ARRAY_SIZE + (mCounter - (index % ARRAY_SIZE))) % ARRAY_SIZE);
+    return mElements.at((scheduler::ARRAY_SIZE + (mCounter - (index % scheduler::ARRAY_SIZE))) %
+                        scheduler::ARRAY_SIZE);
 }
 
 } // namespace android
\ No newline at end of file
diff --git a/services/surfaceflinger/Scheduler/LayerHistory.h b/services/surfaceflinger/Scheduler/LayerHistory.h
index 76c1352..c6fab07 100644
--- a/services/surfaceflinger/Scheduler/LayerHistory.h
+++ b/services/surfaceflinger/Scheduler/LayerHistory.h
@@ -25,6 +25,8 @@
 
 #include <utils/Timers.h>
 
+#include "SchedulerUtils.h"
+
 namespace android {
 
 /*
@@ -52,12 +54,11 @@
     const std::unordered_map<std::string, nsecs_t>& get(size_t index) const;
     // Returns the total size of the ring buffer. The value is always the same regardless
     // of how many slots we filled in.
-    static constexpr size_t getSize() { return ARRAY_SIZE; }
+    static constexpr size_t getSize() { return scheduler::ARRAY_SIZE; }
 
 private:
     size_t mCounter = 0;
-    static constexpr size_t ARRAY_SIZE = 30;
-    std::array<std::unordered_map<std::string, nsecs_t>, ARRAY_SIZE> mElements;
+    std::array<std::unordered_map<std::string, nsecs_t>, scheduler::ARRAY_SIZE> mElements;
 };
 
 } // namespace android
\ No newline at end of file
diff --git a/services/surfaceflinger/Scheduler/Scheduler.cpp b/services/surfaceflinger/Scheduler/Scheduler.cpp
index 4d3ae33..4457f72 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.cpp
+++ b/services/surfaceflinger/Scheduler/Scheduler.cpp
@@ -18,6 +18,7 @@
 
 #include "Scheduler.h"
 
+#include <algorithm>
 #include <cinttypes>
 #include <cstdint>
 #include <memory>
@@ -38,6 +39,7 @@
 #include "EventControlThread.h"
 #include "EventThread.h"
 #include "InjectVSyncSource.h"
+#include "SchedulerUtils.h"
 
 namespace android {
 
@@ -222,11 +224,6 @@
     mLayerHistory.incrementCounter();
 }
 
-nsecs_t Scheduler::calculateAverage() const {
-    nsecs_t sum = std::accumulate(mTimeDifferences.begin(), mTimeDifferences.end(), 0);
-    return (sum / ARRAY_SIZE);
-}
-
 void Scheduler::updateFrameSkipping(const int64_t skipCount) {
     ATRACE_INT("FrameSkipCount", skipCount);
     if (mSkipCount != skipCount) {
@@ -243,6 +240,7 @@
 
     // Traverse through the layer history, and determine the differences in present times.
     nsecs_t newestPresentTime = framePresentTime;
+    std::string differencesText = "";
     for (int i = 1; i < mLayerHistory.getSize(); i++) {
         std::unordered_map<std::string, nsecs_t> layers = mLayerHistory.get(i);
         for (auto layer : layers) {
@@ -250,39 +248,31 @@
                 continue;
             }
             int64_t differenceMs = (newestPresentTime - layer.second) / 1000000;
-            ALOGD("%d Layer %s: %" PRId64, i, layerName.c_str(), differenceMs);
             // Dismiss noise.
             if (differenceMs > 10 && differenceMs < 60) {
                 differencesMs.push_back(differenceMs);
             }
+            IF_ALOGV() { differencesText += (std::to_string(differenceMs) + " "); }
             newestPresentTime = layer.second;
         }
     }
-    // Average is a good indicator for when 24fps videos are playing, because the frames come in
-    // 33, and 49 ms intervals with occasional 41ms.
-    int64_t average =
-            std::accumulate(differencesMs.begin(), differencesMs.end(), 0) / differencesMs.size();
-    const auto tag = "TimestampAvg_" + layerName;
-    ATRACE_INT(tag.c_str(), average);
+    ALOGV("Layer %s timestamp intervals: %s", layerName.c_str(), differencesText.c_str());
 
-    // Mode and median are good indicators for 30 and 60 fps videos, because the majority of frames
-    // come in 16, or 33 ms intervals.
-    // TODO(b/113612090): Calculate mode. Median is good for now, since we want a given interval to
-    // repeat at least ARRAY_SIZE/2 + 1 times.
-    if (differencesMs.size() > 0) {
+    if (!differencesMs.empty()) {
+        // Mean/Average is a good indicator for when 24fps videos are playing, because the frames
+        // come in 33, and 49 ms intervals with occasional 41ms.
+        const int64_t meanMs = scheduler::calculate_mean(differencesMs);
+        const auto tagMean = "TimestampMean_" + layerName;
+        ATRACE_INT(tagMean.c_str(), meanMs);
+
+        // Mode and median are good indicators for 30 and 60 fps videos, because the majority of
+        // frames come in 16, or 33 ms intervals.
         const auto tagMedian = "TimestampMedian_" + layerName;
-        ATRACE_INT(tagMedian.c_str(), calculateMedian(&differencesMs));
-    }
-}
+        ATRACE_INT(tagMedian.c_str(), scheduler::calculate_median(&differencesMs));
 
-int64_t Scheduler::calculateMedian(std::vector<int64_t>* v) {
-    if (!v || v->size() == 0) {
-        return 0;
+        const auto tagMode = "TimestampMode_" + layerName;
+        ATRACE_INT(tagMode.c_str(), scheduler::calculate_mode(differencesMs));
     }
-
-    size_t n = v->size() / 2;
-    nth_element(v->begin(), v->begin() + n, v->end());
-    return v->at(n);
 }
 
 void Scheduler::determineTimestampAverage(bool isAutoTimestamp, const nsecs_t framePresentTime) {
@@ -302,23 +292,21 @@
     }
     ATRACE_INT("TimestampDiff", differenceMs);
 
-    mTimeDifferences[mCounter % ARRAY_SIZE] = differenceMs;
+    mTimeDifferences[mCounter % scheduler::ARRAY_SIZE] = differenceMs;
     mCounter++;
-    nsecs_t average = calculateAverage();
-    ATRACE_INT("TimestampAverage", average);
+    int64_t mean = scheduler::calculate_mean(mTimeDifferences);
+    ATRACE_INT("AutoTimestampMean", mean);
 
     // TODO(b/113612090): This are current numbers from trial and error while running videos
     // from YouTube at 24, 30, and 60 fps.
-    if (average > 14 && average < 18) {
+    if (mean > 14 && mean < 18) {
         ATRACE_INT("FPS", 60);
-    } else if (average > 31 && average < 34) {
+    } else if (mean > 31 && mean < 34) {
         ATRACE_INT("FPS", 30);
-        updateFrameSkipping(1);
         return;
-    } else if (average > 39 && average < 42) {
+    } else if (mean > 39 && mean < 42) {
         ATRACE_INT("FPS", 24);
     }
-    updateFrameSkipping(0);
 }
 
 } // namespace android
diff --git a/services/surfaceflinger/Scheduler/Scheduler.h b/services/surfaceflinger/Scheduler/Scheduler.h
index adfc071..764ad00 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.h
+++ b/services/surfaceflinger/Scheduler/Scheduler.h
@@ -27,6 +27,7 @@
 #include "EventThread.h"
 #include "InjectVSyncSource.h"
 #include "LayerHistory.h"
+#include "SchedulerUtils.h"
 
 namespace android {
 
@@ -111,8 +112,6 @@
     void incrementFrameCounter();
 
 protected:
-    friend class SchedulerTest;
-
     virtual std::unique_ptr<EventThread> makeEventThread(
             const std::string& connectionName, DispSync* dispSync, int64_t phaseOffsetNs,
             impl::EventThread::ResyncWithRateLimitCallback resyncCallback,
@@ -124,9 +123,6 @@
     // Collects the statistical mean (average) and median between timestamp
     // intervals for each frame for each layer.
     void determineLayerTimestampStats(const std::string layerName, const nsecs_t framePresentTime);
-    // Calculates the statistical median in the vector. Return 0 if the vector is empty. The
-    // function modifies the vector contents.
-    int64_t calculateMedian(std::vector<int64_t>* v);
     // Collects the average difference between timestamps for each frame regardless
     // of which layer the timestamp came from.
     void determineTimestampAverage(bool isAutoTimestamp, const nsecs_t framePresentTime);
@@ -163,8 +159,7 @@
     // simulate 30Hz rendering, we skip every other frame, and this variable is set
     // to 1.
     int64_t mSkipCount = 0;
-    static constexpr size_t ARRAY_SIZE = 30;
-    std::array<int64_t, ARRAY_SIZE> mTimeDifferences;
+    std::array<int64_t, scheduler::ARRAY_SIZE> mTimeDifferences{};
     size_t mCounter = 0;
 
     LayerHistory mLayerHistory;
diff --git a/services/surfaceflinger/Scheduler/SchedulerUtils.cpp b/services/surfaceflinger/Scheduler/SchedulerUtils.cpp
new file mode 100644
index 0000000..191022d
--- /dev/null
+++ b/services/surfaceflinger/Scheduler/SchedulerUtils.cpp
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2018 The Android Open Source Project
+ *
+ * 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 "SchedulerUtils.h"
+
+#include <cinttypes>
+#include <numeric>
+#include <unordered_map>
+#include <vector>
+
+namespace android {
+namespace scheduler {
+
+int64_t calculate_median(std::vector<int64_t>* v) {
+    if (!v || v->empty()) {
+        return 0;
+    }
+
+    size_t n = v->size() / 2;
+    nth_element(v->begin(), v->begin() + n, v->end());
+    return v->at(n);
+}
+
+int64_t calculate_mode(const std::vector<int64_t>& v) {
+    if (v.empty()) {
+        return 0;
+    }
+
+    // Create a map with all the counts for the indivicual values in the vector.
+    std::unordered_map<int64_t, int64_t> counts;
+    for (int64_t value : v) {
+        counts[value]++;
+    }
+
+    // Sort the map, and return the number with the highest count. If two numbers have
+    // the same count, first one is returned.
+    using ValueType = const decltype(counts)::value_type&;
+    const auto compareCounts = [](ValueType l, ValueType r) { return l.second <= r.second; };
+    return std::max_element(counts.begin(), counts.end(), compareCounts)->first;
+}
+
+} // namespace scheduler
+} // namespace android
diff --git a/services/surfaceflinger/Scheduler/SchedulerUtils.h b/services/surfaceflinger/Scheduler/SchedulerUtils.h
new file mode 100644
index 0000000..17c57db
--- /dev/null
+++ b/services/surfaceflinger/Scheduler/SchedulerUtils.h
@@ -0,0 +1,46 @@
+/*
+ * Copyright 2018 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#pragma once
+
+#include <cinttypes>
+#include <numeric>
+#include <vector>
+
+namespace android {
+namespace scheduler {
+// This number is used to set the size of the arrays in scheduler that hold information
+// about layers.
+static constexpr size_t ARRAY_SIZE = 30;
+
+// Calculates the statistical mean (average) in the data structure (array, vector). The
+// function does not modify the contents of the array.
+template <typename T>
+auto calculate_mean(const T& v) {
+    using V = typename T::value_type;
+    V sum = std::accumulate(v.begin(), v.end(), 0);
+    return sum / static_cast<V>(v.size());
+}
+
+// Calculates the statistical median in the vector. Return 0 if the vector is empty. The
+// function modifies the vector contents.
+int64_t calculate_median(std::vector<int64_t>* v);
+
+// Calculates the statistical mode in the vector. Return 0 if the vector is empty.
+int64_t calculate_mode(const std::vector<int64_t>& v);
+
+} // namespace scheduler
+} // namespace android
\ No newline at end of file
diff --git a/services/surfaceflinger/tests/unittests/Android.bp b/services/surfaceflinger/tests/unittests/Android.bp
index 58f1e9c..28f3ef2 100644
--- a/services/surfaceflinger/tests/unittests/Android.bp
+++ b/services/surfaceflinger/tests/unittests/Android.bp
@@ -31,6 +31,7 @@
         "EventThreadTest.cpp",
         "LayerHistoryTest.cpp",
         "SchedulerTest.cpp",
+        "SchedulerUtilsTest.cpp",
         "mock/DisplayHardware/MockComposer.cpp",
         "mock/DisplayHardware/MockDisplaySurface.cpp",
         "mock/DisplayHardware/MockPowerAdvisor.cpp",
diff --git a/services/surfaceflinger/tests/unittests/SchedulerTest.cpp b/services/surfaceflinger/tests/unittests/SchedulerTest.cpp
index e967742..d0cf1b7 100644
--- a/services/surfaceflinger/tests/unittests/SchedulerTest.cpp
+++ b/services/surfaceflinger/tests/unittests/SchedulerTest.cpp
@@ -59,8 +59,6 @@
     SchedulerTest();
     ~SchedulerTest() override;
 
-    int64_t calculateMedian(std::vector<int64_t>* v);
-
     sp<Scheduler::ConnectionHandle> mConnectionHandle;
     mock::DispSync* mPrimaryDispSync = new mock::DispSync();
     mock::EventThread* mEventThread;
@@ -97,10 +95,6 @@
     ALOGD("**** Tearing down after %s.%s\n", test_info->test_case_name(), test_info->name());
 }
 
-int64_t SchedulerTest::calculateMedian(std::vector<int64_t>* v) {
-    return mScheduler->calculateMedian(v);
-}
-
 namespace {
 /* ------------------------------------------------------------------------
  * Test cases
@@ -190,38 +184,5 @@
     EXPECT_CALL(*mEventThread, setPhaseOffset(10)).Times(1);
     ASSERT_NO_FATAL_FAILURE(mScheduler->setPhaseOffset(mConnectionHandle, 10));
 }
-
-TEST_F(SchedulerTest, calculateMedian) {
-    std::vector<int64_t> testVector;
-    // Calling the function on empty vector returns 0.
-    EXPECT_EQ(0, calculateMedian(&testVector));
-
-    testVector.push_back(33);
-    EXPECT_EQ(33, calculateMedian(&testVector));
-    testVector.push_back(33);
-    testVector.push_back(33);
-    EXPECT_EQ(33, calculateMedian(&testVector));
-    testVector.push_back(42);
-    EXPECT_EQ(33, calculateMedian(&testVector));
-    testVector.push_back(33);
-    EXPECT_EQ(33, calculateMedian(&testVector));
-    testVector.push_back(42);
-    EXPECT_EQ(33, calculateMedian(&testVector));
-    testVector.push_back(42);
-    EXPECT_EQ(33, calculateMedian(&testVector));
-    testVector.push_back(42);
-    EXPECT_EQ(42, calculateMedian(&testVector));
-    testVector.push_back(60);
-    EXPECT_EQ(42, calculateMedian(&testVector));
-    testVector.push_back(60);
-    EXPECT_EQ(42, calculateMedian(&testVector));
-    testVector.push_back(33);
-    EXPECT_EQ(42, calculateMedian(&testVector));
-    testVector.push_back(33);
-    EXPECT_EQ(42, calculateMedian(&testVector));
-    testVector.push_back(33);
-    EXPECT_EQ(33, calculateMedian(&testVector));
-}
-
 } // namespace
 } // namespace android
diff --git a/services/surfaceflinger/tests/unittests/SchedulerUtilsTest.cpp b/services/surfaceflinger/tests/unittests/SchedulerUtilsTest.cpp
new file mode 100644
index 0000000..5865579
--- /dev/null
+++ b/services/surfaceflinger/tests/unittests/SchedulerUtilsTest.cpp
@@ -0,0 +1,131 @@
+/*
+ * Copyright 2018 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#undef LOG_TAG
+#define LOG_TAG "SchedulerUnittests"
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+#include <array>
+
+#include "Scheduler/SchedulerUtils.h"
+
+namespace android {
+namespace scheduler {
+
+class SchedulerUtilsTest : public testing::Test {
+public:
+    SchedulerUtilsTest() = default;
+    ~SchedulerUtilsTest() override = default;
+};
+
+namespace {
+TEST_F(SchedulerUtilsTest, calculate_mean) {
+    std::array<int64_t, 30> testArray{};
+    // Calling the function on empty array returns 0.
+    EXPECT_EQ(0, calculate_mean(testArray));
+
+    testArray[0] = 33;
+    EXPECT_EQ(1, calculate_mean(testArray));
+    testArray[1] = 33;
+    testArray[2] = 33;
+    EXPECT_EQ(3, calculate_mean(testArray));
+    testArray[3] = 42;
+    EXPECT_EQ(4, calculate_mean(testArray));
+    testArray[4] = 33;
+    EXPECT_EQ(5, calculate_mean(testArray));
+    testArray[5] = 42;
+    EXPECT_EQ(7, calculate_mean(testArray));
+    for (int i = 6; i < 30; i++) {
+        testArray[i] = 33;
+    }
+    EXPECT_EQ(33, calculate_mean(testArray));
+}
+
+TEST_F(SchedulerUtilsTest, calculate_median) {
+    std::vector<int64_t> testVector;
+    // Calling the function on empty vector returns 0.
+    EXPECT_EQ(0, calculate_median(&testVector));
+
+    testVector.push_back(33);
+    EXPECT_EQ(33, calculate_median(&testVector));
+    testVector.push_back(33);
+    testVector.push_back(33);
+    EXPECT_EQ(33, calculate_median(&testVector));
+    testVector.push_back(42);
+    EXPECT_EQ(33, calculate_median(&testVector));
+    testVector.push_back(33);
+    EXPECT_EQ(33, calculate_median(&testVector));
+    testVector.push_back(42);
+    EXPECT_EQ(33, calculate_median(&testVector));
+    testVector.push_back(42);
+    EXPECT_EQ(33, calculate_median(&testVector));
+    testVector.push_back(42);
+    EXPECT_EQ(42, calculate_median(&testVector));
+    testVector.push_back(60);
+    EXPECT_EQ(42, calculate_median(&testVector));
+    testVector.push_back(60);
+    EXPECT_EQ(42, calculate_median(&testVector));
+    testVector.push_back(33);
+    EXPECT_EQ(42, calculate_median(&testVector));
+    testVector.push_back(33);
+    EXPECT_EQ(42, calculate_median(&testVector));
+    testVector.push_back(33);
+    EXPECT_EQ(33, calculate_median(&testVector));
+}
+
+TEST_F(SchedulerUtilsTest, calculate_mode) {
+    std::vector<int64_t> testVector;
+    // Calling the function on empty vector returns 0.
+    EXPECT_EQ(0, calculate_mode(testVector));
+
+    testVector.push_back(33);
+    EXPECT_EQ(33, calculate_mode(testVector));
+    testVector.push_back(33);
+    testVector.push_back(33);
+    EXPECT_EQ(33, calculate_mode(testVector));
+    testVector.push_back(42);
+    EXPECT_EQ(33, calculate_mode(testVector));
+    testVector.push_back(33);
+    EXPECT_EQ(33, calculate_mode(testVector));
+    testVector.push_back(42);
+    EXPECT_EQ(33, calculate_mode(testVector));
+    testVector.push_back(42);
+    EXPECT_EQ(33, calculate_mode(testVector));
+    testVector.push_back(42);
+    EXPECT_EQ(33, calculate_mode(testVector));
+    testVector.push_back(60);
+    EXPECT_EQ(33, calculate_mode(testVector));
+    testVector.push_back(60);
+    EXPECT_EQ(33, calculate_mode(testVector));
+    testVector.push_back(33);
+    // 5 occurences of 33.
+    EXPECT_EQ(33, calculate_mode(testVector));
+    testVector.push_back(42);
+    // 5 occurences of 33, 5 occurences of 42. We choose the first one.
+    EXPECT_EQ(33, calculate_mode(testVector));
+    testVector.push_back(42);
+    // 5 occurences of 33, 6 occurences of 42.
+    EXPECT_EQ(42, calculate_mode(testVector));
+    testVector.push_back(42);
+    // 5 occurences of 33, 7 occurences of 42.
+    EXPECT_EQ(42, calculate_mode(testVector));
+}
+
+} // namespace
+} // namespace scheduler
+} // namespace android
\ No newline at end of file