diff --git a/media/libheadtracking/Android.bp b/media/libheadtracking/Android.bp
index f64aedf..5bffb42 100644
--- a/media/libheadtracking/Android.bp
+++ b/media/libheadtracking/Android.bp
@@ -21,6 +21,7 @@
       "ScreenHeadFusion.cpp",
       "StillnessDetector.cpp",
       "Twist.cpp",
+      "VectorRecorder.cpp",
     ],
     shared_libs: [
         "libaudioutils",
@@ -35,6 +36,9 @@
     export_header_lib_headers: [
         "libeigen",
     ],
+    cflags: [
+        "-Wthread-safety",
+    ],
 }
 
 cc_library {
diff --git a/media/libheadtracking/VectorRecorder.cpp b/media/libheadtracking/VectorRecorder.cpp
new file mode 100644
index 0000000..5d0588e
--- /dev/null
+++ b/media/libheadtracking/VectorRecorder.cpp
@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2023 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 "media/VectorRecorder.h"
+
+namespace android::media {
+
+// Convert data to string with level indentation.
+// No need for a lock as the SimpleLog is thread-safe.
+std::string VectorRecorder::toString(size_t indent) const {
+    return mRecordLog.dumpToString(std::string(indent + 1, ' ').c_str(), mMaxLocalLogLine);
+}
+
+// Record into local log when it is time.
+void VectorRecorder::record(const std::vector<float>& record) {
+    if (record.size() != mVectorSize) return;
+
+    // Protect against concurrent calls to record().
+    std::lock_guard lg(mLock);
+
+    // if it is time, record average data and reset.
+    if (shouldRecordLog_l()) {
+        sumToAverage_l();
+        mRecordLog.log(
+                "mean: %s, min: %s, max %s, calculated %zu samples in %0.4f second(s)",
+                toString(mSum).c_str(),
+                toString(mMin).c_str(),
+                toString(mMax).c_str(),
+                mNumberOfSamples,
+                mNumberOfSecondsSinceFirstSample.count());
+        resetRecord_l();
+    }
+
+    // update stream average.
+    if (mNumberOfSamples++ == 0) {
+        mFirstSampleTimestamp = std::chrono::steady_clock::now();
+        for (size_t i = 0; i < mVectorSize; ++i) {
+            const float value = record[i];
+            mSum[i] += value;
+            mMax[i] = value;
+            mMin[i] = value;
+        }
+    } else {
+        for (size_t i = 0; i < mVectorSize; ++i) {
+            const float value = record[i];
+            mSum[i] += value;
+            mMax[i] = std::max(mMax[i], value);
+            mMin[i] = std::min(mMin[i], value);
+        }
+    }
+}
+
+bool VectorRecorder::shouldRecordLog_l() {
+    mNumberOfSecondsSinceFirstSample = std::chrono::duration_cast<std::chrono::seconds>(
+            std::chrono::steady_clock::now() - mFirstSampleTimestamp);
+    return mNumberOfSecondsSinceFirstSample >= mRecordThreshold;
+}
+
+void VectorRecorder::resetRecord_l() {
+    mSum.assign(mVectorSize, 0);
+    mMax.assign(mVectorSize, 0);
+    mMin.assign(mVectorSize, 0);
+    mNumberOfSamples = 0;
+    mNumberOfSecondsSinceFirstSample = std::chrono::seconds(0);
+}
+
+void VectorRecorder::sumToAverage_l() {
+    if (mNumberOfSamples == 0) return;
+    const float reciprocal = 1.f / mNumberOfSamples;
+    for (auto& p : mSum) {
+        p *= reciprocal;
+    }
+}
+
+}  // namespace android::media
diff --git a/media/libheadtracking/include/media/VectorRecorder.h b/media/libheadtracking/include/media/VectorRecorder.h
new file mode 100644
index 0000000..1fb7521
--- /dev/null
+++ b/media/libheadtracking/include/media/VectorRecorder.h
@@ -0,0 +1,114 @@
+/*
+ * Copyright (C) 2023 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 <android-base/stringprintf.h>
+#include <android-base/thread_annotations.h>
+#include <audio_utils/SimpleLog.h>
+#include <chrono>
+#include <math.h>
+#include <mutex>
+#include <vector>
+
+namespace android::media {
+
+/**
+ * VectorRecorder records a vector of floats computing the average, max, and min
+ * over given time periods.
+ *
+ * The class is thread-safe.
+ */
+class VectorRecorder {
+  public:
+    VectorRecorder(
+        size_t vectorSize, std::chrono::duration<double> threshold, int maxLogLine)
+        : mVectorSize(vectorSize)
+        , mRecordLog(maxLogLine)
+        , mRecordThreshold(threshold)
+    {
+        resetRecord_l();  // OK to call - we're in the constructor.
+    }
+
+    /** Convert recorded vector data to string with level indentation */
+    std::string toString(size_t indent) const;
+
+    /**
+     * @brief Record a vector of floats.
+     *
+     * @param record a vector of floats.
+     */
+    void record(const std::vector<float>& record);
+
+    /**
+     * Format vector to a string, [0.00, 0.00, 0.00, -1.29, -0.50, 15.27].
+     */
+    template <typename T>
+    static std::string toString(const std::vector<T>& record) {
+        if (record.size() == 0) {
+            return "[]";
+        }
+
+        std::string ss = "[";
+        for (size_t i = 0; i < record.size(); ++i) {
+            if (i > 0) {
+                ss.append(", ");
+            }
+            base::StringAppendF(&ss, "%0.2lf", static_cast<double>(record[i]));
+        }
+        ss.append("]");
+        return ss;
+    }
+
+  private:
+    static constexpr int mMaxLocalLogLine = 10;
+
+    const size_t mVectorSize;
+
+    // Local log for historical vector data.
+    // Locked internally, so does not need mutex below.
+    SimpleLog mRecordLog{mMaxLocalLogLine};
+
+    std::mutex mLock;
+
+    // Time threshold to record vectors in the local log.
+    // Vector data will be recorded into log at least every mRecordThreshold.
+    std::chrono::duration<double> mRecordThreshold GUARDED_BY(mLock);
+
+    // Number of seconds since first sample in mSum.
+    std::chrono::duration<double> mNumberOfSecondsSinceFirstSample GUARDED_BY(mLock);
+
+    // Timestamp of first sample recorded in mSum.
+    std::chrono::time_point<std::chrono::steady_clock> mFirstSampleTimestamp GUARDED_BY(mLock);
+
+    // Number of samples in mSum.
+    size_t mNumberOfSamples GUARDED_BY(mLock) = 0;
+
+    std::vector<double> mSum GUARDED_BY(mLock);
+    std::vector<float> mMax GUARDED_BY(mLock);
+    std::vector<float> mMin GUARDED_BY(mLock);
+
+    // Computes mNumberOfSecondsSinceFirstSample, returns true if time to record.
+    bool shouldRecordLog_l() REQUIRES(mLock);
+
+    // Resets the running mNumberOfSamples, mSum, mMax, mMin.
+    void resetRecord_l() REQUIRES(mLock);
+
+    // Convert mSum to an average.
+    void sumToAverage_l() REQUIRES(mLock);
+};  // VectorRecorder
+
+}  // namespace android::media
diff --git a/services/audiopolicy/service/Spatializer.cpp b/services/audiopolicy/service/Spatializer.cpp
index 2fe7b9e..cf9543c 100644
--- a/services/audiopolicy/service/Spatializer.cpp
+++ b/services/audiopolicy/service/Spatializer.cpp
@@ -75,6 +75,16 @@
     return maxMask;
 }
 
+std::vector<float> recordFromRotationVector(const std::vector<float>& rotationVector) {
+    constexpr float RAD_TO_DEGREE = 180.f / M_PI;
+    std::vector<float> record{
+        rotationVector[0], rotationVector[1], rotationVector[2],
+        rotationVector[3] * RAD_TO_DEGREE,
+        rotationVector[4] * RAD_TO_DEGREE,
+        rotationVector[5] * RAD_TO_DEGREE};
+    return record;
+}
+
 // ---------------------------------------------------------------------------
 
 class Spatializer::EngineCallbackHandler : public AHandler {
@@ -185,41 +195,6 @@
 };
 
 // ---------------------------------------------------------------------------
-
-// Convert recorded sensor data to string with level indentation.
-std::string Spatializer::HeadToStagePoseRecorder::toString(unsigned level) const {
-    std::string prefixSpace(level, ' ');
-    return mPoseRecordLog.dumpToString((prefixSpace + " ").c_str(), Spatializer::mMaxLocalLogLine);
-}
-
-// Compute sensor data, record into local log when it is time.
-void Spatializer::HeadToStagePoseRecorder::record(const std::vector<float>& headToStage) {
-    if (headToStage.size() != mPoseVectorSize) return;
-
-    if (mNumOfSampleSinceLastRecord++ == 0) {
-        mFirstSampleTimestamp = std::chrono::steady_clock::now();
-    }
-    // if it's time, do record and reset.
-    if (shouldRecordLog()) {
-        poseSumToAverage();
-        mPoseRecordLog.log(
-                "mean: %s, min: %s, max %s, calculated %d samples in %0.4f second(s)",
-                Spatializer::toString<double>(mPoseRadianSum, true /* radianToDegree */).c_str(),
-                Spatializer::toString<float>(mMinPoseAngle, true /* radianToDegree */).c_str(),
-                Spatializer::toString<float>(mMaxPoseAngle, true /* radianToDegree */).c_str(),
-                mNumOfSampleSinceLastRecord, mNumOfSecondsSinceLastRecord.count());
-        resetRecord();
-    }
-    // update stream average.
-    for (int i = 0; i < mPoseVectorSize; i++) {
-        mPoseRadianSum[i] += headToStage[i];
-        mMaxPoseAngle[i] = std::max(mMaxPoseAngle[i], headToStage[i]);
-        mMinPoseAngle[i] = std::min(mMinPoseAngle[i], headToStage[i]);
-    }
-    return;
-}
-
-// ---------------------------------------------------------------------------
 sp<Spatializer> Spatializer::create(SpatializerPolicyCallback *callback) {
     sp<Spatializer> spatializer;
 
@@ -590,7 +565,8 @@
     }
     std::lock_guard lock(mLock);
     if (mPoseController != nullptr) {
-        mLocalLog.log("%s with screenToStage %s", __func__, toString<float>(screenToStage).c_str());
+        mLocalLog.log("%s with screenToStage %s", __func__,
+                media::VectorRecorder::toString<float>(screenToStage).c_str());
         mPoseController->setScreenToStagePose(maybePose.value());
     }
     return Status::ok();
diff --git a/services/audiopolicy/service/Spatializer.h b/services/audiopolicy/service/Spatializer.h
index 7415b1e..f03d764 100644
--- a/services/audiopolicy/service/Spatializer.h
+++ b/services/audiopolicy/service/Spatializer.h
@@ -26,6 +26,7 @@
 #include <audio_utils/SimpleLog.h>
 #include <math.h>
 #include <media/AudioEffect.h>
+#include <media/VectorRecorder.h>
 #include <media/audiohal/EffectHalInterface.h>
 #include <media/stagefright/foundation/ALooper.h>
 #include <system/audio_effects/effect_spatializer.h>
@@ -170,30 +171,6 @@
         return result.has_value() ? media::toString(*result) : "unknown_latency_mode";
     }
 
-    /**
-     * Format head to stage vector to a string, [0.00, 0.00, 0.00, -1.29, -0.50, 15.27].
-     */
-    template <typename T>
-    static std::string toString(const std::vector<T>& vec, bool radianToDegree = false) {
-        if (vec.size() == 0) {
-            return "[]";
-        }
-
-        std::string ss = "[";
-        for (auto f = vec.begin(); f != vec.end(); ++f) {
-            if (f != vec.begin()) {
-                ss .append(", ");
-            }
-            if (radianToDegree) {
-                base::StringAppendF(&ss, "%0.2f", HeadToStagePoseRecorder::getDegreeWithRadian(*f));
-            } else {
-                base::StringAppendF(&ss, "%f", *f);
-            }
-        }
-        ss.append("]");
-        return ss;
-    };
-
     // If the Spatializer is not created, we send the status for metrics purposes.
     // OK:      Spatializer not expected to be created.
     // NO_INIT: Spatializer creation failed.
@@ -425,92 +402,12 @@
      * @brief Calculate and record sensor data.
      * Dump to local log with max/average pose angle every mPoseRecordThreshold.
      */
-    class HeadToStagePoseRecorder {
-      public:
-        HeadToStagePoseRecorder(std::chrono::duration<double> threshold, int maxLogLine)
-            : mPoseRecordThreshold(threshold), mPoseRecordLog(maxLogLine) {
-            resetRecord();
-        }
-
-        /** Convert recorded sensor data to string with level indentation */
-        std::string toString(unsigned level) const;
-
-        /**
-         * @brief Calculate sensor data, record into local log when it is time.
-         *
-         * @param headToStage The vector from Pose3f::toVector().
-         */
-        void record(const std::vector<float>& headToStage);
-
-        static constexpr float getDegreeWithRadian(const float radian) {
-            float radianToDegreeRatio = (180 / PI);
-            return (radian * radianToDegreeRatio);
-        }
-
-      private:
-        static constexpr float PI = M_PI;
-        /**
-         * Pose recorder time threshold to record sensor data in local log.
-         * Sensor data will be recorded into log at least every mPoseRecordThreshold.
-         */
-        std::chrono::duration<double> mPoseRecordThreshold;
-        // Number of seconds pass since last record.
-        std::chrono::duration<double> mNumOfSecondsSinceLastRecord;
-        /**
-         * According to frameworks/av/media/libheadtracking/include/media/Pose.h
-         * "The vector will have exactly 6 elements, where the first three are a translation vector
-         * and the last three are a rotation vector."
-         */
-        static constexpr size_t mPoseVectorSize = 6;
-        /**
-         * Timestamp of last sensor data record in local log.
-         */
-        std::chrono::time_point<std::chrono::steady_clock> mFirstSampleTimestamp;
-        /**
-         * Number of sensor samples received since last record, sample rate is ~100Hz which produce
-         * ~6k samples/minute.
-         */
-        uint32_t mNumOfSampleSinceLastRecord = 0;
-        /* The sum of pose angle represented by radian since last dump, div
-         * mNumOfSampleSinceLastRecord to get arithmetic mean. Largest possible value: 2PI * 100Hz *
-         * mPoseRecordThreshold.
-         */
-        std::vector<double> mPoseRadianSum;
-        std::vector<float> mMaxPoseAngle;
-        std::vector<float> mMinPoseAngle;
-        // Local log for history sensor data.
-        SimpleLog mPoseRecordLog{mMaxLocalLogLine};
-
-        bool shouldRecordLog() {
-            mNumOfSecondsSinceLastRecord = std::chrono::duration_cast<std::chrono::seconds>(
-                    std::chrono::steady_clock::now() - mFirstSampleTimestamp);
-            return mNumOfSecondsSinceLastRecord >= mPoseRecordThreshold;
-        }
-
-        void resetRecord() {
-            mPoseRadianSum.assign(mPoseVectorSize, 0);
-            mMaxPoseAngle.assign(mPoseVectorSize, -PI);
-            mMinPoseAngle.assign(mPoseVectorSize, PI);
-            mNumOfSampleSinceLastRecord = 0;
-            mNumOfSecondsSinceLastRecord = std::chrono::seconds(0);
-        }
-
-        // Add each sample to sum and only calculate when record.
-        void poseSumToAverage() {
-            if (mNumOfSampleSinceLastRecord == 0) return;
-            for (auto& p : mPoseRadianSum) {
-                const float reciprocal = 1.f / mNumOfSampleSinceLastRecord;
-                p *= reciprocal;
-            }
-        }
-    };  // HeadToStagePoseRecorder
-
     // Record one log line per second (up to mMaxLocalLogLine) to capture most recent sensor data.
-    HeadToStagePoseRecorder mPoseRecorder GUARDED_BY(mLock) =
-            HeadToStagePoseRecorder(std::chrono::seconds(1), mMaxLocalLogLine);
+    media::VectorRecorder mPoseRecorder GUARDED_BY(mLock) {
+        6 /* vectorSize */, std::chrono::seconds(1), mMaxLocalLogLine };
     // Record one log line per minute (up to mMaxLocalLogLine) to capture durable sensor data.
-    HeadToStagePoseRecorder mPoseDurableRecorder GUARDED_BY(mLock) =
-            HeadToStagePoseRecorder(std::chrono::minutes(1), mMaxLocalLogLine);
+    media::VectorRecorder mPoseDurableRecorder  GUARDED_BY(mLock) {
+        6 /* vectorSize */, std::chrono::minutes(1), mMaxLocalLogLine };
 };  // Spatializer
 
 }; // namespace android