diff --git a/media/libaaudio/src/Android.bp b/media/libaaudio/src/Android.bp
index f50b53a..e262a38 100644
--- a/media/libaaudio/src/Android.bp
+++ b/media/libaaudio/src/Android.bp
@@ -93,7 +93,6 @@
         "-Wno-unused-parameter",
         "-Wall",
         "-Werror",
-
         // By default, all symbols are hidden.
         // "-fvisibility=hidden",
         // AAUDIO_API is used to explicitly export a function or a variable as a visible symbol.
diff --git a/media/libaaudio/src/client/AAudioFlowGraph.cpp b/media/libaaudio/src/client/AAudioFlowGraph.cpp
index d0c3238..2ed3e3c 100644
--- a/media/libaaudio/src/client/AAudioFlowGraph.cpp
+++ b/media/libaaudio/src/client/AAudioFlowGraph.cpp
@@ -35,7 +35,7 @@
 #include <flowgraph/SourceI24.h>
 #include <flowgraph/SourceI32.h>
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 aaudio_result_t AAudioFlowGraph::configure(audio_format_t sourceFormat,
                           int32_t sourceChannelCount,
diff --git a/media/libaaudio/src/client/AAudioFlowGraph.h b/media/libaaudio/src/client/AAudioFlowGraph.h
index 00b6575..602c17f 100644
--- a/media/libaaudio/src/client/AAudioFlowGraph.h
+++ b/media/libaaudio/src/client/AAudioFlowGraph.h
@@ -72,17 +72,19 @@
     void setRampLengthInFrames(int32_t numFrames);
 
 private:
-    std::unique_ptr<flowgraph::FlowGraphSourceBuffered>     mSource;
-    std::unique_ptr<flowgraph::MonoBlend>                   mMonoBlend;
-    std::unique_ptr<flowgraph::ClipToRange>                 mClipper;
-    std::unique_ptr<flowgraph::MonoToMultiConverter>        mChannelConverter;
-    std::unique_ptr<flowgraph::ManyToMultiConverter>        mManyToMultiConverter;
-    std::unique_ptr<flowgraph::MultiToManyConverter>        mMultiToManyConverter;
-    std::vector<std::unique_ptr<flowgraph::RampLinear>>     mVolumeRamps;
-    std::vector<float>                                      mPanningVolumes;
-    float                                                   mTargetVolume = 1.0f;
-    android::audio_utils::Balance                           mBalance;
-    std::unique_ptr<flowgraph::FlowGraphSink>               mSink;
+    std::unique_ptr<FLOWGRAPH_OUTER_NAMESPACE::flowgraph::FlowGraphSourceBuffered> mSource;
+    std::unique_ptr<FLOWGRAPH_OUTER_NAMESPACE::flowgraph::MonoBlend> mMonoBlend;
+    std::unique_ptr<FLOWGRAPH_OUTER_NAMESPACE::flowgraph::ClipToRange> mClipper;
+    std::unique_ptr<FLOWGRAPH_OUTER_NAMESPACE::flowgraph::MonoToMultiConverter> mChannelConverter;
+    std::unique_ptr<FLOWGRAPH_OUTER_NAMESPACE::flowgraph::ManyToMultiConverter>
+            mManyToMultiConverter;
+    std::unique_ptr<FLOWGRAPH_OUTER_NAMESPACE::flowgraph::MultiToManyConverter>
+            mMultiToManyConverter;
+    std::vector<std::unique_ptr<FLOWGRAPH_OUTER_NAMESPACE::flowgraph::RampLinear>> mVolumeRamps;
+    std::vector<float> mPanningVolumes;
+    float mTargetVolume = 1.0f;
+    android::audio_utils::Balance mBalance;
+    std::unique_ptr<FLOWGRAPH_OUTER_NAMESPACE::flowgraph::FlowGraphSink> mSink;
 };
 
 
diff --git a/media/libaaudio/src/flowgraph/ChannelCountConverter.cpp b/media/libaaudio/src/flowgraph/ChannelCountConverter.cpp
index 351def2..dc80427 100644
--- a/media/libaaudio/src/flowgraph/ChannelCountConverter.cpp
+++ b/media/libaaudio/src/flowgraph/ChannelCountConverter.cpp
@@ -18,7 +18,7 @@
 #include "FlowGraphNode.h"
 #include "ChannelCountConverter.h"
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 ChannelCountConverter::ChannelCountConverter(
         int32_t inputChannelCount,
diff --git a/media/libaaudio/src/flowgraph/ChannelCountConverter.h b/media/libaaudio/src/flowgraph/ChannelCountConverter.h
index e4b6f4e..858f4d4 100644
--- a/media/libaaudio/src/flowgraph/ChannelCountConverter.h
+++ b/media/libaaudio/src/flowgraph/ChannelCountConverter.h
@@ -22,7 +22,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 /**
  * Change the number of number of channels without mixing.
@@ -47,6 +47,6 @@
         FlowGraphPortFloatOutput output;
     };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif //FLOWGRAPH_CHANNEL_COUNT_CONVERTER_H
diff --git a/media/libaaudio/src/flowgraph/ClipToRange.cpp b/media/libaaudio/src/flowgraph/ClipToRange.cpp
index d2f8a02..c6ad0b0 100644
--- a/media/libaaudio/src/flowgraph/ClipToRange.cpp
+++ b/media/libaaudio/src/flowgraph/ClipToRange.cpp
@@ -19,7 +19,7 @@
 #include "FlowGraphNode.h"
 #include "ClipToRange.h"
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 ClipToRange::ClipToRange(int32_t channelCount)
         : FlowGraphFilter(channelCount) {
diff --git a/media/libaaudio/src/flowgraph/ClipToRange.h b/media/libaaudio/src/flowgraph/ClipToRange.h
index 22b7804..2fddeee 100644
--- a/media/libaaudio/src/flowgraph/ClipToRange.h
+++ b/media/libaaudio/src/flowgraph/ClipToRange.h
@@ -23,7 +23,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 // This is 3 dB, (10^(3/20)), to match the maximum headroom in AudioTrack for float data.
 // It is designed to allow occasional transient peaks.
@@ -63,6 +63,6 @@
     float mMaximum = kDefaultMaxHeadroom;
 };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif //FLOWGRAPH_CLIP_TO_RANGE_H
diff --git a/media/libaaudio/src/flowgraph/FlowGraphNode.cpp b/media/libaaudio/src/flowgraph/FlowGraphNode.cpp
index 4c76e77..012abe7 100644
--- a/media/libaaudio/src/flowgraph/FlowGraphNode.cpp
+++ b/media/libaaudio/src/flowgraph/FlowGraphNode.cpp
@@ -19,7 +19,7 @@
 #include <sys/types.h>
 #include "FlowGraphNode.h"
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 /***************************************************************************/
 int32_t FlowGraphNode::pullData(int32_t numFrames, int64_t callCount) {
@@ -68,7 +68,7 @@
         : FlowGraphPort(parent, samplesPerFrame)
         , mFramesPerBuffer(framesPerBuffer)
         , mBuffer(nullptr) {
-    size_t numFloats = framesPerBuffer * getSamplesPerFrame();
+    size_t numFloats = static_cast<size_t>(framesPerBuffer) * getSamplesPerFrame();
     mBuffer = std::make_unique<float[]>(numFloats);
 }
 
diff --git a/media/libaaudio/src/flowgraph/FlowGraphNode.h b/media/libaaudio/src/flowgraph/FlowGraphNode.h
index 69c83dd..2884c08 100644
--- a/media/libaaudio/src/flowgraph/FlowGraphNode.h
+++ b/media/libaaudio/src/flowgraph/FlowGraphNode.h
@@ -38,13 +38,26 @@
 // TODO Review use of raw pointers for connect(). Maybe use smart pointers but need to avoid
 //      run-time deallocation in audio thread.
 
-// Set this to 1 if using it inside the Android framework.
-// This code is kept here so that it can be moved easily between Oboe and AAudio.
-#ifndef FLOWGRAPH_ANDROID_INTERNAL
-#define FLOWGRAPH_ANDROID_INTERNAL 0
-#endif
+// Set flags FLOWGRAPH_ANDROID_INTERNAL and FLOWGRAPH_OUTER_NAMESPACE based on whether compiler
+// flag __ANDROID_NDK__ is defined. __ANDROID_NDK__ should be defined in oboe and not aaudio.
 
-namespace flowgraph {
+#ifndef FLOWGRAPH_ANDROID_INTERNAL
+#ifdef __ANDROID_NDK__
+#define FLOWGRAPH_ANDROID_INTERNAL 0
+#else
+#define FLOWGRAPH_ANDROID_INTERNAL 1
+#endif // __ANDROID_NDK__
+#endif // FLOWGRAPH_ANDROID_INTERNAL
+
+#ifndef FLOWGRAPH_OUTER_NAMESPACE
+#ifdef __ANDROID_NDK__
+#define FLOWGRAPH_OUTER_NAMESPACE oboe
+#else
+#define FLOWGRAPH_OUTER_NAMESPACE aaudio
+#endif // __ANDROID_NDK__
+#endif // FLOWGRAPH_OUTER_NAMESPACE
+
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 // Default block size that can be overridden when the FlowGraphPortFloat is created.
 // If it is too small then we will have too much overhead from switching between nodes.
@@ -432,6 +445,6 @@
     FlowGraphPortFloatOutput output;
 };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif /* FLOWGRAPH_FLOW_GRAPH_NODE_H */
diff --git a/media/libaaudio/src/flowgraph/FlowgraphUtilities.h b/media/libaaudio/src/flowgraph/FlowgraphUtilities.h
index b750410..ce2bc82 100644
--- a/media/libaaudio/src/flowgraph/FlowgraphUtilities.h
+++ b/media/libaaudio/src/flowgraph/FlowgraphUtilities.h
@@ -19,7 +19,7 @@
 
 #include <unistd.h>
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 class FlowgraphUtilities {
 public:
diff --git a/media/libaaudio/src/flowgraph/ManyToMultiConverter.cpp b/media/libaaudio/src/flowgraph/ManyToMultiConverter.cpp
index 879685e..4f973bc 100644
--- a/media/libaaudio/src/flowgraph/ManyToMultiConverter.cpp
+++ b/media/libaaudio/src/flowgraph/ManyToMultiConverter.cpp
@@ -18,7 +18,7 @@
 
 #include "ManyToMultiConverter.h"
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 ManyToMultiConverter::ManyToMultiConverter(int32_t channelCount)
         : inputs(channelCount)
diff --git a/media/libaaudio/src/flowgraph/ManyToMultiConverter.h b/media/libaaudio/src/flowgraph/ManyToMultiConverter.h
index c7460ff..50644cf 100644
--- a/media/libaaudio/src/flowgraph/ManyToMultiConverter.h
+++ b/media/libaaudio/src/flowgraph/ManyToMultiConverter.h
@@ -23,7 +23,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 /**
  * Combine multiple mono inputs into one interleaved multi-channel output.
@@ -48,6 +48,6 @@
 private:
 };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif //FLOWGRAPH_MANY_TO_MULTI_CONVERTER_H
diff --git a/media/libaaudio/src/flowgraph/MonoBlend.cpp b/media/libaaudio/src/flowgraph/MonoBlend.cpp
index 62e2809..4fd75e1 100644
--- a/media/libaaudio/src/flowgraph/MonoBlend.cpp
+++ b/media/libaaudio/src/flowgraph/MonoBlend.cpp
@@ -18,7 +18,7 @@
 
 #include "MonoBlend.h"
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 MonoBlend::MonoBlend(int32_t channelCount)
         : FlowGraphFilter(channelCount)
@@ -43,4 +43,4 @@
     }
 
     return numFrames;
-}
\ No newline at end of file
+}
diff --git a/media/libaaudio/src/flowgraph/MonoBlend.h b/media/libaaudio/src/flowgraph/MonoBlend.h
index 7e3c35b..f8d44ff 100644
--- a/media/libaaudio/src/flowgraph/MonoBlend.h
+++ b/media/libaaudio/src/flowgraph/MonoBlend.h
@@ -22,7 +22,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 /**
  * Combine data between multiple channels so each channel is an average
@@ -43,6 +43,6 @@
     const float mInvChannelCount;
 };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif //FLOWGRAPH_MONO_BLEND
diff --git a/media/libaaudio/src/flowgraph/MonoToMultiConverter.cpp b/media/libaaudio/src/flowgraph/MonoToMultiConverter.cpp
index c8d60b9..33eed52 100644
--- a/media/libaaudio/src/flowgraph/MonoToMultiConverter.cpp
+++ b/media/libaaudio/src/flowgraph/MonoToMultiConverter.cpp
@@ -18,7 +18,7 @@
 #include "FlowGraphNode.h"
 #include "MonoToMultiConverter.h"
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 MonoToMultiConverter::MonoToMultiConverter(int32_t outputChannelCount)
         : input(*this, 1)
diff --git a/media/libaaudio/src/flowgraph/MonoToMultiConverter.h b/media/libaaudio/src/flowgraph/MonoToMultiConverter.h
index 6e87ccb..762edb0 100644
--- a/media/libaaudio/src/flowgraph/MonoToMultiConverter.h
+++ b/media/libaaudio/src/flowgraph/MonoToMultiConverter.h
@@ -22,7 +22,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 /**
  * Convert a monophonic stream to a multi-channel interleaved stream
@@ -44,6 +44,6 @@
     FlowGraphPortFloatOutput output;
 };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif //FLOWGRAPH_MONO_TO_MULTI_CONVERTER_H
diff --git a/media/libaaudio/src/flowgraph/MultiToManyConverter.cpp b/media/libaaudio/src/flowgraph/MultiToManyConverter.cpp
index f074364..5cdf594 100644
--- a/media/libaaudio/src/flowgraph/MultiToManyConverter.cpp
+++ b/media/libaaudio/src/flowgraph/MultiToManyConverter.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 The Android Open Source Project
+ * Copyright 2021 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.
@@ -18,7 +18,7 @@
 #include "FlowGraphNode.h"
 #include "MultiToManyConverter.h"
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 MultiToManyConverter::MultiToManyConverter(int32_t channelCount)
         : outputs(channelCount)
@@ -45,4 +45,3 @@
 
     return numFrames;
 }
-
diff --git a/media/libaaudio/src/flowgraph/MultiToManyConverter.h b/media/libaaudio/src/flowgraph/MultiToManyConverter.h
index de31475..dee40a2 100644
--- a/media/libaaudio/src/flowgraph/MultiToManyConverter.h
+++ b/media/libaaudio/src/flowgraph/MultiToManyConverter.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 The Android Open Source Project
+ * Copyright 2021 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.
@@ -22,7 +22,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 /**
  * Convert a multi-channel interleaved stream to multiple mono-channel
@@ -44,6 +44,6 @@
         flowgraph::FlowGraphPortFloatInput input;
     };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
-#endif //FLOWGRAPH_MULTI_TO_MANY_CONVERTER_H
+#endif //FLOWGRAPH_MULTI_TO_MANY_CONVERTER_H
\ No newline at end of file
diff --git a/media/libaaudio/src/flowgraph/MultiToMonoConverter.cpp b/media/libaaudio/src/flowgraph/MultiToMonoConverter.cpp
index c745108..467f95e 100644
--- a/media/libaaudio/src/flowgraph/MultiToMonoConverter.cpp
+++ b/media/libaaudio/src/flowgraph/MultiToMonoConverter.cpp
@@ -18,7 +18,7 @@
 #include "FlowGraphNode.h"
 #include "MultiToMonoConverter.h"
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 MultiToMonoConverter::MultiToMonoConverter(int32_t inputChannelCount)
         : input(*this, inputChannelCount)
diff --git a/media/libaaudio/src/flowgraph/MultiToMonoConverter.h b/media/libaaudio/src/flowgraph/MultiToMonoConverter.h
index 37c53bd..bf5b7b6 100644
--- a/media/libaaudio/src/flowgraph/MultiToMonoConverter.h
+++ b/media/libaaudio/src/flowgraph/MultiToMonoConverter.h
@@ -22,7 +22,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 /**
  * Convert a multi-channel interleaved stream to a monophonic stream
@@ -44,6 +44,6 @@
         FlowGraphPortFloatOutput output;
     };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif //FLOWGRAPH_MULTI_TO_MONO_CONVERTER_H
diff --git a/media/libaaudio/src/flowgraph/RampLinear.cpp b/media/libaaudio/src/flowgraph/RampLinear.cpp
index 905ae07..80ac72a 100644
--- a/media/libaaudio/src/flowgraph/RampLinear.cpp
+++ b/media/libaaudio/src/flowgraph/RampLinear.cpp
@@ -19,7 +19,7 @@
 #include "FlowGraphNode.h"
 #include "RampLinear.h"
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 RampLinear::RampLinear(int32_t channelCount)
         : FlowGraphFilter(channelCount) {
diff --git a/media/libaaudio/src/flowgraph/RampLinear.h b/media/libaaudio/src/flowgraph/RampLinear.h
index f285704..3839d6e 100644
--- a/media/libaaudio/src/flowgraph/RampLinear.h
+++ b/media/libaaudio/src/flowgraph/RampLinear.h
@@ -23,7 +23,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 /**
  * When the target is modified then the output will ramp smoothly
@@ -91,6 +91,6 @@
     float               mLevelTo         = 0.0f;
 };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif //FLOWGRAPH_RAMP_LINEAR_H
diff --git a/media/libaaudio/src/flowgraph/SampleRateConverter.cpp b/media/libaaudio/src/flowgraph/SampleRateConverter.cpp
index 5c3ed1f..a15fcb8 100644
--- a/media/libaaudio/src/flowgraph/SampleRateConverter.cpp
+++ b/media/libaaudio/src/flowgraph/SampleRateConverter.cpp
@@ -16,10 +16,11 @@
 
 #include "SampleRateConverter.h"
 
-using namespace flowgraph;
-using namespace resampler;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
+using namespace RESAMPLER_OUTER_NAMESPACE::resampler;
 
-SampleRateConverter::SampleRateConverter(int32_t channelCount, MultiChannelResampler &resampler)
+SampleRateConverter::SampleRateConverter(int32_t channelCount,
+                                         MultiChannelResampler &resampler)
         : FlowGraphFilter(channelCount)
         , mResampler(resampler) {
     setDataPulledAutomatically(false);
diff --git a/media/libaaudio/src/flowgraph/SampleRateConverter.h b/media/libaaudio/src/flowgraph/SampleRateConverter.h
index 57d76a4..f883e6c 100644
--- a/media/libaaudio/src/flowgraph/SampleRateConverter.h
+++ b/media/libaaudio/src/flowgraph/SampleRateConverter.h
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#ifndef OBOE_SAMPLE_RATE_CONVERTER_H
-#define OBOE_SAMPLE_RATE_CONVERTER_H
+#ifndef FLOWGRAPH_SAMPLE_RATE_CONVERTER_H
+#define FLOWGRAPH_SAMPLE_RATE_CONVERTER_H
 
 #include <unistd.h>
 #include <sys/types.h>
@@ -23,7 +23,7 @@
 #include "FlowGraphNode.h"
 #include "resampler/MultiChannelResampler.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 class SampleRateConverter : public FlowGraphFilter {
 public:
@@ -58,6 +58,6 @@
 
 };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
-#endif //OBOE_SAMPLE_RATE_CONVERTER_H
+#endif //FLOWGRAPH_SAMPLE_RATE_CONVERTER_H
diff --git a/media/libaaudio/src/flowgraph/SinkFloat.cpp b/media/libaaudio/src/flowgraph/SinkFloat.cpp
index 0588848..940a66b 100644
--- a/media/libaaudio/src/flowgraph/SinkFloat.cpp
+++ b/media/libaaudio/src/flowgraph/SinkFloat.cpp
@@ -19,7 +19,7 @@
 #include "FlowGraphNode.h"
 #include "SinkFloat.h"
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 SinkFloat::SinkFloat(int32_t channelCount)
         : FlowGraphSink(channelCount) {
diff --git a/media/libaaudio/src/flowgraph/SinkFloat.h b/media/libaaudio/src/flowgraph/SinkFloat.h
index c812373..3be3f5d 100644
--- a/media/libaaudio/src/flowgraph/SinkFloat.h
+++ b/media/libaaudio/src/flowgraph/SinkFloat.h
@@ -23,7 +23,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 /**
  * AudioSink that lets you read data as 32-bit floats.
@@ -40,6 +40,6 @@
     }
 };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif //FLOWGRAPH_SINK_FLOAT_H
diff --git a/media/libaaudio/src/flowgraph/SinkI16.cpp b/media/libaaudio/src/flowgraph/SinkI16.cpp
index da7fd6b..690431c 100644
--- a/media/libaaudio/src/flowgraph/SinkI16.cpp
+++ b/media/libaaudio/src/flowgraph/SinkI16.cpp
@@ -23,7 +23,7 @@
 #include <audio_utils/primitives.h>
 #endif
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 SinkI16::SinkI16(int32_t channelCount)
         : FlowGraphSink(channelCount) {}
diff --git a/media/libaaudio/src/flowgraph/SinkI16.h b/media/libaaudio/src/flowgraph/SinkI16.h
index 1e1ce3a..bf124f5 100644
--- a/media/libaaudio/src/flowgraph/SinkI16.h
+++ b/media/libaaudio/src/flowgraph/SinkI16.h
@@ -22,7 +22,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 /**
  * AudioSink that lets you read data as 16-bit signed integers.
@@ -38,6 +38,6 @@
     }
 };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif //FLOWGRAPH_SINK_I16_H
diff --git a/media/libaaudio/src/flowgraph/SinkI24.cpp b/media/libaaudio/src/flowgraph/SinkI24.cpp
index a9fb5d2..d4f68b6 100644
--- a/media/libaaudio/src/flowgraph/SinkI24.cpp
+++ b/media/libaaudio/src/flowgraph/SinkI24.cpp
@@ -25,7 +25,7 @@
 #include <audio_utils/primitives.h>
 #endif
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 SinkI24::SinkI24(int32_t channelCount)
         : FlowGraphSink(channelCount) {}
diff --git a/media/libaaudio/src/flowgraph/SinkI24.h b/media/libaaudio/src/flowgraph/SinkI24.h
index 44078a9..6b4135e 100644
--- a/media/libaaudio/src/flowgraph/SinkI24.h
+++ b/media/libaaudio/src/flowgraph/SinkI24.h
@@ -22,7 +22,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 /**
  * AudioSink that lets you read data as packed 24-bit signed integers.
@@ -39,6 +39,6 @@
     }
 };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif //FLOWGRAPH_SINK_I24_H
diff --git a/media/libaaudio/src/flowgraph/SinkI32.cpp b/media/libaaudio/src/flowgraph/SinkI32.cpp
index 9fd4e96..b14b3d2 100644
--- a/media/libaaudio/src/flowgraph/SinkI32.cpp
+++ b/media/libaaudio/src/flowgraph/SinkI32.cpp
@@ -14,15 +14,15 @@
  * limitations under the License.
  */
 
-#if FLOWGRAPH_ANDROID_INTERNAL
-#include <audio_utils/primitives.h>
-#endif
-
 #include "FlowGraphNode.h"
 #include "FlowgraphUtilities.h"
 #include "SinkI32.h"
 
-using namespace flowgraph;
+#if FLOWGRAPH_ANDROID_INTERNAL
+#include <audio_utils/primitives.h>
+#endif
+
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 SinkI32::SinkI32(int32_t channelCount)
         : FlowGraphSink(channelCount) {}
diff --git a/media/libaaudio/src/flowgraph/SinkI32.h b/media/libaaudio/src/flowgraph/SinkI32.h
index 7456d5f..35507ea 100644
--- a/media/libaaudio/src/flowgraph/SinkI32.h
+++ b/media/libaaudio/src/flowgraph/SinkI32.h
@@ -21,7 +21,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 class SinkI32 : public FlowGraphSink {
 public:
@@ -35,6 +35,6 @@
     }
 };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif //FLOWGRAPH_SINK_I32_H
diff --git a/media/libaaudio/src/flowgraph/SourceFloat.cpp b/media/libaaudio/src/flowgraph/SourceFloat.cpp
index 1b3daf1..a0c8827 100644
--- a/media/libaaudio/src/flowgraph/SourceFloat.cpp
+++ b/media/libaaudio/src/flowgraph/SourceFloat.cpp
@@ -19,7 +19,7 @@
 #include "FlowGraphNode.h"
 #include "SourceFloat.h"
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 SourceFloat::SourceFloat(int32_t channelCount)
         : FlowGraphSourceBuffered(channelCount) {
diff --git a/media/libaaudio/src/flowgraph/SourceFloat.h b/media/libaaudio/src/flowgraph/SourceFloat.h
index 4719669..78053e5 100644
--- a/media/libaaudio/src/flowgraph/SourceFloat.h
+++ b/media/libaaudio/src/flowgraph/SourceFloat.h
@@ -22,7 +22,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 /**
  * AudioSource that reads a block of pre-defined float data.
@@ -39,6 +39,6 @@
     }
 };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif //FLOWGRAPH_SOURCE_FLOAT_H
diff --git a/media/libaaudio/src/flowgraph/SourceI16.cpp b/media/libaaudio/src/flowgraph/SourceI16.cpp
index 8813023..16cd2b3 100644
--- a/media/libaaudio/src/flowgraph/SourceI16.cpp
+++ b/media/libaaudio/src/flowgraph/SourceI16.cpp
@@ -24,7 +24,7 @@
 #include <audio_utils/primitives.h>
 #endif
 
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 SourceI16::SourceI16(int32_t channelCount)
         : FlowGraphSourceBuffered(channelCount) {
diff --git a/media/libaaudio/src/flowgraph/SourceI16.h b/media/libaaudio/src/flowgraph/SourceI16.h
index fe440b2..923890c 100644
--- a/media/libaaudio/src/flowgraph/SourceI16.h
+++ b/media/libaaudio/src/flowgraph/SourceI16.h
@@ -22,7 +22,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 /**
  * AudioSource that reads a block of pre-defined 16-bit integer data.
  */
@@ -37,6 +37,6 @@
     }
 };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif //FLOWGRAPH_SOURCE_I16_H
diff --git a/media/libaaudio/src/flowgraph/SourceI24.cpp b/media/libaaudio/src/flowgraph/SourceI24.cpp
index 1975878..d54b958 100644
--- a/media/libaaudio/src/flowgraph/SourceI24.cpp
+++ b/media/libaaudio/src/flowgraph/SourceI24.cpp
@@ -17,14 +17,14 @@
 #include <algorithm>
 #include <unistd.h>
 
+#include "FlowGraphNode.h"
+#include "SourceI24.h"
+
 #if FLOWGRAPH_ANDROID_INTERNAL
 #include <audio_utils/primitives.h>
 #endif
 
-#include "FlowGraphNode.h"
-#include "SourceI24.h"
-
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 constexpr int kBytesPerI24Packed = 3;
 
diff --git a/media/libaaudio/src/flowgraph/SourceI24.h b/media/libaaudio/src/flowgraph/SourceI24.h
index 3779534..fb66d4a 100644
--- a/media/libaaudio/src/flowgraph/SourceI24.h
+++ b/media/libaaudio/src/flowgraph/SourceI24.h
@@ -22,7 +22,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 /**
  * AudioSource that reads a block of pre-defined 24-bit packed integer data.
@@ -38,6 +38,6 @@
     }
 };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif //FLOWGRAPH_SOURCE_I24_H
diff --git a/media/libaaudio/src/flowgraph/SourceI32.cpp b/media/libaaudio/src/flowgraph/SourceI32.cpp
index 4b2e8c4..b1c8f75 100644
--- a/media/libaaudio/src/flowgraph/SourceI32.cpp
+++ b/media/libaaudio/src/flowgraph/SourceI32.cpp
@@ -17,14 +17,14 @@
 #include <algorithm>
 #include <unistd.h>
 
+#include "FlowGraphNode.h"
+#include "SourceI32.h"
+
 #if FLOWGRAPH_ANDROID_INTERNAL
 #include <audio_utils/primitives.h>
 #endif
 
-#include "FlowGraphNode.h"
-#include "SourceI32.h"
-
-using namespace flowgraph;
+using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
 
 SourceI32::SourceI32(int32_t channelCount)
         : FlowGraphSourceBuffered(channelCount) {
diff --git a/media/libaaudio/src/flowgraph/SourceI32.h b/media/libaaudio/src/flowgraph/SourceI32.h
index b4e0d7b..7109469 100644
--- a/media/libaaudio/src/flowgraph/SourceI32.h
+++ b/media/libaaudio/src/flowgraph/SourceI32.h
@@ -21,7 +21,7 @@
 
 #include "FlowGraphNode.h"
 
-namespace flowgraph {
+namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph {
 
 class SourceI32 : public FlowGraphSourceBuffered {
 public:
@@ -37,6 +37,6 @@
     static constexpr float kScale = 1.0 / (1UL << 31);
 };
 
-} /* namespace flowgraph */
+} /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */
 
 #endif //FLOWGRAPH_SOURCE_I32_H
diff --git a/media/libaaudio/src/flowgraph/resampler/HyperbolicCosineWindow.h b/media/libaaudio/src/flowgraph/resampler/HyperbolicCosineWindow.h
index f6479ae..76ec0e7 100644
--- a/media/libaaudio/src/flowgraph/resampler/HyperbolicCosineWindow.h
+++ b/media/libaaudio/src/flowgraph/resampler/HyperbolicCosineWindow.h
@@ -19,7 +19,9 @@
 
 #include <math.h>
 
-namespace resampler {
+#include "ResamplerDefinitions.h"
+
+namespace RESAMPLER_OUTER_NAMESPACE::resampler {
 
 /**
  * Calculate a HyperbolicCosineWindow window centered at 0.
@@ -64,5 +66,6 @@
     double mInverseCoshAlpha = 1.0;
 };
 
-} // namespace resampler
+} /* namespace RESAMPLER_OUTER_NAMESPACE::resampler */
+
 #endif //RESAMPLER_HYPERBOLIC_COSINE_WINDOW_H
diff --git a/media/libaaudio/src/flowgraph/resampler/IntegerRatio.cpp b/media/libaaudio/src/flowgraph/resampler/IntegerRatio.cpp
index 4bd75b3..39e9b24 100644
--- a/media/libaaudio/src/flowgraph/resampler/IntegerRatio.cpp
+++ b/media/libaaudio/src/flowgraph/resampler/IntegerRatio.cpp
@@ -16,7 +16,7 @@
 
 #include "IntegerRatio.h"
 
-using namespace resampler;
+using namespace RESAMPLER_OUTER_NAMESPACE::resampler;
 
 // Enough primes to cover the common sample rates.
 static const int kPrimes[] = {
diff --git a/media/libaaudio/src/flowgraph/resampler/IntegerRatio.h b/media/libaaudio/src/flowgraph/resampler/IntegerRatio.h
index 8c044d8..a6b524c 100644
--- a/media/libaaudio/src/flowgraph/resampler/IntegerRatio.h
+++ b/media/libaaudio/src/flowgraph/resampler/IntegerRatio.h
@@ -14,12 +14,14 @@
  * limitations under the License.
  */
 
-#ifndef OBOE_INTEGER_RATIO_H
-#define OBOE_INTEGER_RATIO_H
+#ifndef RESAMPLER_INTEGER_RATIO_H
+#define RESAMPLER_INTEGER_RATIO_H
 
 #include <sys/types.h>
 
-namespace resampler {
+#include "ResamplerDefinitions.h"
+
+namespace RESAMPLER_OUTER_NAMESPACE::resampler {
 
 /**
  * Represent the ratio of two integers.
@@ -47,6 +49,6 @@
     int32_t mDenominator;
 };
 
-} // namespace resampler
+} /* namespace RESAMPLER_OUTER_NAMESPACE::resampler */
 
-#endif //OBOE_INTEGER_RATIO_H
+#endif //RESAMPLER_INTEGER_RATIO_H
diff --git a/media/libaaudio/src/flowgraph/resampler/KaiserWindow.h b/media/libaaudio/src/flowgraph/resampler/KaiserWindow.h
index 73dbc41..f99f9b4 100644
--- a/media/libaaudio/src/flowgraph/resampler/KaiserWindow.h
+++ b/media/libaaudio/src/flowgraph/resampler/KaiserWindow.h
@@ -19,7 +19,9 @@
 
 #include <math.h>
 
-namespace resampler {
+#include "ResamplerDefinitions.h"
+
+namespace RESAMPLER_OUTER_NAMESPACE::resampler {
 
 /**
  * Calculate a Kaiser window centered at 0.
@@ -83,5 +85,6 @@
     double mInverseBesselBeta = 1.0;
 };
 
-} // namespace resampler
+} /* namespace RESAMPLER_OUTER_NAMESPACE::resampler */
+
 #endif //RESAMPLER_KAISER_WINDOW_H
diff --git a/media/libaaudio/src/flowgraph/resampler/LinearResampler.cpp b/media/libaaudio/src/flowgraph/resampler/LinearResampler.cpp
index a7748c1..cb4932a 100644
--- a/media/libaaudio/src/flowgraph/resampler/LinearResampler.cpp
+++ b/media/libaaudio/src/flowgraph/resampler/LinearResampler.cpp
@@ -16,7 +16,7 @@
 
 #include "LinearResampler.h"
 
-using namespace resampler;
+using namespace RESAMPLER_OUTER_NAMESPACE::resampler;
 
 LinearResampler::LinearResampler(const MultiChannelResampler::Builder &builder)
         : MultiChannelResampler(builder) {
diff --git a/media/libaaudio/src/flowgraph/resampler/LinearResampler.h b/media/libaaudio/src/flowgraph/resampler/LinearResampler.h
index 6bde81d..5434379 100644
--- a/media/libaaudio/src/flowgraph/resampler/LinearResampler.h
+++ b/media/libaaudio/src/flowgraph/resampler/LinearResampler.h
@@ -14,15 +14,17 @@
  * limitations under the License.
  */
 
-#ifndef OBOE_LINEAR_RESAMPLER_H
-#define OBOE_LINEAR_RESAMPLER_H
+#ifndef RESAMPLER_LINEAR_RESAMPLER_H
+#define RESAMPLER_LINEAR_RESAMPLER_H
 
 #include <memory>
 #include <sys/types.h>
 #include <unistd.h>
-#include "MultiChannelResampler.h"
 
-namespace resampler {
+#include "MultiChannelResampler.h"
+#include "ResamplerDefinitions.h"
+
+namespace RESAMPLER_OUTER_NAMESPACE::resampler {
 
 /**
  * Simple resampler that uses bi-linear interpolation.
@@ -40,5 +42,6 @@
     std::unique_ptr<float[]> mCurrentFrame;
 };
 
-} // namespace resampler
-#endif //OBOE_LINEAR_RESAMPLER_H
+} /* namespace RESAMPLER_OUTER_NAMESPACE::resampler */
+
+#endif //RESAMPLER_LINEAR_RESAMPLER_H
diff --git a/media/libaaudio/src/flowgraph/resampler/MultiChannelResampler.cpp b/media/libaaudio/src/flowgraph/resampler/MultiChannelResampler.cpp
index d630520..7193ff3 100644
--- a/media/libaaudio/src/flowgraph/resampler/MultiChannelResampler.cpp
+++ b/media/libaaudio/src/flowgraph/resampler/MultiChannelResampler.cpp
@@ -25,11 +25,12 @@
 #include "SincResampler.h"
 #include "SincResamplerStereo.h"
 
-using namespace resampler;
+using namespace RESAMPLER_OUTER_NAMESPACE::resampler;
 
 MultiChannelResampler::MultiChannelResampler(const MultiChannelResampler::Builder &builder)
         : mNumTaps(builder.getNumTaps())
-        , mX(builder.getChannelCount() * builder.getNumTaps() * 2)
+        , mX(static_cast<size_t>(builder.getChannelCount())
+                * static_cast<size_t>(builder.getNumTaps()) * 2)
         , mSingleFrame(builder.getChannelCount())
         , mChannelCount(builder.getChannelCount())
         {
@@ -110,7 +111,7 @@
     if (--mCursor < 0) {
         mCursor = getNumTaps() - 1;
     }
-    float *dest = &mX[mCursor * getChannelCount()];
+    float *dest = &mX[static_cast<size_t>(mCursor) * static_cast<size_t>(getChannelCount())];
     int offset = getNumTaps() * getChannelCount();
     for (int channel = 0; channel < getChannelCount(); channel++) {
         // Write twice so we avoid having to wrap when reading.
@@ -130,7 +131,7 @@
                                               int32_t numRows,
                                               double phaseIncrement,
                                               float normalizedCutoff) {
-    mCoefficients.resize(getNumTaps() * numRows);
+    mCoefficients.resize(static_cast<size_t>(getNumTaps()) * static_cast<size_t>(numRows));
     int coefficientIndex = 0;
     double phase = 0.0; // ranges from 0.0 to 1.0, fraction between samples
     // Stretch the sinc function for low pass filtering.
@@ -150,7 +151,7 @@
 #if MCR_USE_KAISER
             float window = mKaiserWindow(tapPhase * numTapsHalfInverse);
 #else
-            float window = mCoshWindow(tapPhase * numTapsHalfInverse);
+            float window = mCoshWindow(static_cast<double>(tapPhase) * numTapsHalfInverse);
 #endif
             float coefficient = sinc(radians * cutoffScaler) * window;
             mCoefficients.at(coefficientIndex++) = coefficient;
diff --git a/media/libaaudio/src/flowgraph/resampler/MultiChannelResampler.h b/media/libaaudio/src/flowgraph/resampler/MultiChannelResampler.h
index da79cad..717f3fd 100644
--- a/media/libaaudio/src/flowgraph/resampler/MultiChannelResampler.h
+++ b/media/libaaudio/src/flowgraph/resampler/MultiChannelResampler.h
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#ifndef OBOE_MULTICHANNEL_RESAMPLER_H
-#define OBOE_MULTICHANNEL_RESAMPLER_H
+#ifndef RESAMPLER_MULTICHANNEL_RESAMPLER_H
+#define RESAMPLER_MULTICHANNEL_RESAMPLER_H
 
 #include <memory>
 #include <vector>
@@ -34,7 +34,9 @@
 #include "HyperbolicCosineWindow.h"
 #endif
 
-namespace resampler {
+#include "ResamplerDefinitions.h"
+
+namespace RESAMPLER_OUTER_NAMESPACE::resampler {
 
 class MultiChannelResampler {
 
@@ -267,5 +269,6 @@
     const int              mChannelCount;
 };
 
-} // namespace resampler
-#endif //OBOE_MULTICHANNEL_RESAMPLER_H
+} /* namespace RESAMPLER_OUTER_NAMESPACE::resampler */
+
+#endif //RESAMPLER_MULTICHANNEL_RESAMPLER_H
diff --git a/media/libaaudio/src/flowgraph/resampler/PolyphaseResampler.cpp b/media/libaaudio/src/flowgraph/resampler/PolyphaseResampler.cpp
index aa4ffd9..e47ee8e 100644
--- a/media/libaaudio/src/flowgraph/resampler/PolyphaseResampler.cpp
+++ b/media/libaaudio/src/flowgraph/resampler/PolyphaseResampler.cpp
@@ -19,7 +19,7 @@
 #include "IntegerRatio.h"
 #include "PolyphaseResampler.h"
 
-using namespace resampler;
+using namespace RESAMPLER_OUTER_NAMESPACE::resampler;
 
 PolyphaseResampler::PolyphaseResampler(const MultiChannelResampler::Builder &builder)
         : MultiChannelResampler(builder)
@@ -42,7 +42,7 @@
 
     // Multiply input times windowed sinc function.
     float *coefficients = &mCoefficients[mCoefficientCursor];
-    float *xFrame = &mX[mCursor * getChannelCount()];
+    float *xFrame = &mX[static_cast<size_t>(mCursor) * static_cast<size_t>(getChannelCount())];
     for (int i = 0; i < mNumTaps; i++) {
         float coefficient = *coefficients++;
         for (int channel = 0; channel < getChannelCount(); channel++) {
diff --git a/media/libaaudio/src/flowgraph/resampler/PolyphaseResampler.h b/media/libaaudio/src/flowgraph/resampler/PolyphaseResampler.h
index 1aeb680..3642fce 100644
--- a/media/libaaudio/src/flowgraph/resampler/PolyphaseResampler.h
+++ b/media/libaaudio/src/flowgraph/resampler/PolyphaseResampler.h
@@ -14,16 +14,18 @@
  * limitations under the License.
  */
 
-#ifndef OBOE_POLYPHASE_RESAMPLER_H
-#define OBOE_POLYPHASE_RESAMPLER_H
+#ifndef RESAMPLER_POLYPHASE_RESAMPLER_H
+#define RESAMPLER_POLYPHASE_RESAMPLER_H
 
 #include <memory>
 #include <vector>
 #include <sys/types.h>
 #include <unistd.h>
-#include "MultiChannelResampler.h"
 
-namespace resampler {
+#include "MultiChannelResampler.h"
+#include "ResamplerDefinitions.h"
+
+namespace RESAMPLER_OUTER_NAMESPACE::resampler {
 /**
  * Resampler that is optimized for a reduced ratio of sample rates.
  * All of the coefficients for each possible phase value are pre-calculated.
@@ -46,6 +48,6 @@
 
 };
 
-} // namespace resampler
+} /* namespace RESAMPLER_OUTER_NAMESPACE::resampler */
 
-#endif //OBOE_POLYPHASE_RESAMPLER_H
+#endif //RESAMPLER_POLYPHASE_RESAMPLER_H
diff --git a/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerMono.cpp b/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerMono.cpp
index c0e29b7..fdaf13e 100644
--- a/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerMono.cpp
+++ b/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerMono.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "PolyphaseResamplerMono.h"
 
-using namespace resampler;
+using namespace RESAMPLER_OUTER_NAMESPACE::resampler;
 
 #define MONO  1
 
diff --git a/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerMono.h b/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerMono.h
index 0a691a3..fe020b5 100644
--- a/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerMono.h
+++ b/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerMono.h
@@ -14,14 +14,16 @@
  * limitations under the License.
  */
 
-#ifndef OBOE_POLYPHASE_RESAMPLER_MONO_H
-#define OBOE_POLYPHASE_RESAMPLER_MONO_H
+#ifndef RESAMPLER_POLYPHASE_RESAMPLER_MONO_H
+#define RESAMPLER_POLYPHASE_RESAMPLER_MONO_H
 
 #include <sys/types.h>
 #include <unistd.h>
-#include "PolyphaseResampler.h"
 
-namespace resampler {
+#include "PolyphaseResampler.h"
+#include "ResamplerDefinitions.h"
+
+namespace RESAMPLER_OUTER_NAMESPACE::resampler {
 
 class PolyphaseResamplerMono : public PolyphaseResampler {
 public:
@@ -34,6 +36,6 @@
     void readFrame(float *frame) override;
 };
 
-} // namespace resampler
+} /* namespace RESAMPLER_OUTER_NAMESPACE::resampler */
 
-#endif //OBOE_POLYPHASE_RESAMPLER_MONO_H
+#endif //RESAMPLER_POLYPHASE_RESAMPLER_MONO_H
diff --git a/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerStereo.cpp b/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerStereo.cpp
index e4bef74..b381851 100644
--- a/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerStereo.cpp
+++ b/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerStereo.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "PolyphaseResamplerStereo.h"
 
-using namespace resampler;
+using namespace RESAMPLER_OUTER_NAMESPACE::resampler;
 
 #define STEREO  2
 
diff --git a/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerStereo.h b/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerStereo.h
index e608483..ee4caba 100644
--- a/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerStereo.h
+++ b/media/libaaudio/src/flowgraph/resampler/PolyphaseResamplerStereo.h
@@ -14,14 +14,16 @@
  * limitations under the License.
  */
 
-#ifndef OBOE_POLYPHASE_RESAMPLER_STEREO_H
-#define OBOE_POLYPHASE_RESAMPLER_STEREO_H
+#ifndef RESAMPLER_POLYPHASE_RESAMPLER_STEREO_H
+#define RESAMPLER_POLYPHASE_RESAMPLER_STEREO_H
 
 #include <sys/types.h>
 #include <unistd.h>
-#include "PolyphaseResampler.h"
 
-namespace resampler {
+#include "PolyphaseResampler.h"
+#include "ResamplerDefinitions.h"
+
+namespace RESAMPLER_OUTER_NAMESPACE::resampler {
 
 class PolyphaseResamplerStereo : public PolyphaseResampler {
 public:
@@ -34,6 +36,6 @@
     void readFrame(float *frame) override;
 };
 
-} // namespace resampler
+} /* namespace RESAMPLER_OUTER_NAMESPACE::resampler */
 
-#endif //OBOE_POLYPHASE_RESAMPLER_STEREO_H
+#endif //RESAMPLER_POLYPHASE_RESAMPLER_STEREO_H
diff --git a/media/libaaudio/src/flowgraph/resampler/README.md b/media/libaaudio/src/flowgraph/resampler/README.md
index 05d8a89..ea319c7 100644
--- a/media/libaaudio/src/flowgraph/resampler/README.md
+++ b/media/libaaudio/src/flowgraph/resampler/README.md
@@ -5,6 +5,17 @@
 The converter is based on a sinc function that has been windowed by a hyperbolic cosine.
 We found this had fewer artifacts than the more traditional Kaiser window.
 
+## Building the Resampler
+
+It is part of [Oboe](https://github.com/google/oboe) but has no dependencies on Oboe.
+So the contents of this folder can be used outside of Oboe.
+
+To build it for use outside of Oboe:
+
+1. Copy the "resampler" folder to a folder in your project that is in the include path.
+2. Add all of the \*.cpp files in the resampler folder to your project IDE or Makefile.
+3. In ResamplerDefinitions.h, define RESAMPLER_OUTER_NAMESPACE with your own project name. Alternatively, use -DRESAMPLER_OUTER_NAMESPACE=mynamespace when compiling to avoid modifying the resampler code.
+
 ## Creating a Resampler
 
 Include the [main header](MultiChannelResampler.h) for the resampler.
@@ -88,4 +99,3 @@
 When you are done, you should delete the Resampler to avoid a memory leak.
 
     delete resampler;
-
diff --git a/media/libaaudio/src/flowgraph/resampler/ResamplerDefinitions.h b/media/libaaudio/src/flowgraph/resampler/ResamplerDefinitions.h
new file mode 100644
index 0000000..c6791ec
--- /dev/null
+++ b/media/libaaudio/src/flowgraph/resampler/ResamplerDefinitions.h
@@ -0,0 +1,27 @@
+/*
+ * Copyright 2022 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.
+ */
+
+// Set flag RESAMPLER_OUTER_NAMESPACE based on whether compiler flag
+// __ANDROID_NDK__ is defined. __ANDROID_NDK__ should be defined in oboe
+// but not in android.
+
+#ifndef RESAMPLER_OUTER_NAMESPACE
+#ifdef __ANDROID_NDK__
+#define RESAMPLER_OUTER_NAMESPACE oboe
+#else
+#define RESAMPLER_OUTER_NAMESPACE aaudio
+#endif // __ANDROID_NDK__
+#endif // RESAMPLER_OUTER_NAMESPACE
diff --git a/media/libaaudio/src/flowgraph/resampler/SincResampler.cpp b/media/libaaudio/src/flowgraph/resampler/SincResampler.cpp
index 5e8a9e0..42d0ca2 100644
--- a/media/libaaudio/src/flowgraph/resampler/SincResampler.cpp
+++ b/media/libaaudio/src/flowgraph/resampler/SincResampler.cpp
@@ -18,7 +18,7 @@
 #include <math.h>
 #include "SincResampler.h"
 
-using namespace resampler;
+using namespace RESAMPLER_OUTER_NAMESPACE::resampler;
 
 SincResampler::SincResampler(const MultiChannelResampler::Builder &builder)
         : MultiChannelResampler(builder)
@@ -52,10 +52,12 @@
         index2 -= mNumRows;
     }
 
-    float *coefficients1 = &mCoefficients[index1 * getNumTaps()];
-    float *coefficients2 = &mCoefficients[index2 * getNumTaps()];
+    float *coefficients1 = &mCoefficients[static_cast<size_t>(index1)
+            * static_cast<size_t>(getNumTaps())];
+    float *coefficients2 = &mCoefficients[static_cast<size_t>(index2)
+            * static_cast<size_t>(getNumTaps())];
 
-    float *xFrame = &mX[mCursor * getChannelCount()];
+    float *xFrame = &mX[static_cast<size_t>(mCursor) * static_cast<size_t>(getChannelCount())];
     for (int i = 0; i < mNumTaps; i++) {
         float coefficient1 = *coefficients1++;
         float coefficient2 = *coefficients2++;
diff --git a/media/libaaudio/src/flowgraph/resampler/SincResampler.h b/media/libaaudio/src/flowgraph/resampler/SincResampler.h
index b235188..05ff092 100644
--- a/media/libaaudio/src/flowgraph/resampler/SincResampler.h
+++ b/media/libaaudio/src/flowgraph/resampler/SincResampler.h
@@ -14,15 +14,17 @@
  * limitations under the License.
  */
 
-#ifndef OBOE_SINC_RESAMPLER_H
-#define OBOE_SINC_RESAMPLER_H
+#ifndef RESAMPLER_SINC_RESAMPLER_H
+#define RESAMPLER_SINC_RESAMPLER_H
 
 #include <memory>
 #include <sys/types.h>
 #include <unistd.h>
-#include "MultiChannelResampler.h"
 
-namespace resampler {
+#include "MultiChannelResampler.h"
+#include "ResamplerDefinitions.h"
+
+namespace RESAMPLER_OUTER_NAMESPACE::resampler {
 
 /**
  * Resampler that can interpolate between coefficients.
@@ -43,5 +45,6 @@
     double             mPhaseScaler = 1.0;
 };
 
-} // namespace resampler
-#endif //OBOE_SINC_RESAMPLER_H
+} /* namespace RESAMPLER_OUTER_NAMESPACE::resampler */
+
+#endif //RESAMPLER_SINC_RESAMPLER_H
diff --git a/media/libaaudio/src/flowgraph/resampler/SincResamplerStereo.cpp b/media/libaaudio/src/flowgraph/resampler/SincResamplerStereo.cpp
index ce00302..432137e 100644
--- a/media/libaaudio/src/flowgraph/resampler/SincResamplerStereo.cpp
+++ b/media/libaaudio/src/flowgraph/resampler/SincResamplerStereo.cpp
@@ -19,7 +19,7 @@
 
 #include "SincResamplerStereo.h"
 
-using namespace resampler;
+using namespace RESAMPLER_OUTER_NAMESPACE::resampler;
 
 #define STEREO  2
 
@@ -54,13 +54,15 @@
     // Determine indices into coefficients table.
     double tablePhase = getIntegerPhase() * mPhaseScaler;
     int index1 = static_cast<int>(floor(tablePhase));
-    float *coefficients1 = &mCoefficients[index1 * getNumTaps()];
+    float *coefficients1 = &mCoefficients[static_cast<size_t>(index1)
+            * static_cast<size_t>(getNumTaps())];
     int index2 = (index1 + 1);
     if (index2 >= mNumRows) { // no guard row needed because we wrap the indices
         index2 = 0;
     }
-    float *coefficients2 = &mCoefficients[index2 * getNumTaps()];
-    float *xFrame = &mX[mCursor * getChannelCount()];
+    float *coefficients2 = &mCoefficients[static_cast<size_t>(index2)
+            * static_cast<size_t>(getNumTaps())];
+    float *xFrame = &mX[static_cast<size_t>(mCursor) * static_cast<size_t>(getChannelCount())];
     for (int i = 0; i < mNumTaps; i++) {
         float coefficient1 = *coefficients1++;
         float coefficient2 = *coefficients2++;
diff --git a/media/libaaudio/src/flowgraph/resampler/SincResamplerStereo.h b/media/libaaudio/src/flowgraph/resampler/SincResamplerStereo.h
index 7d49ec7..d5576d1 100644
--- a/media/libaaudio/src/flowgraph/resampler/SincResamplerStereo.h
+++ b/media/libaaudio/src/flowgraph/resampler/SincResamplerStereo.h
@@ -14,14 +14,16 @@
  * limitations under the License.
  */
 
-#ifndef OBOE_SINC_RESAMPLER_STEREO_H
-#define OBOE_SINC_RESAMPLER_STEREO_H
+#ifndef RESAMPLER_SINC_RESAMPLER_STEREO_H
+#define RESAMPLER_SINC_RESAMPLER_STEREO_H
 
 #include <sys/types.h>
 #include <unistd.h>
-#include "SincResampler.h"
 
-namespace resampler {
+#include "SincResampler.h"
+#include "ResamplerDefinitions.h"
+
+namespace RESAMPLER_OUTER_NAMESPACE::resampler {
 
 class SincResamplerStereo : public SincResampler {
 public:
@@ -35,5 +37,6 @@
 
 };
 
-} // namespace resampler
-#endif //OBOE_SINC_RESAMPLER_STEREO_H
+} /* namespace RESAMPLER_OUTER_NAMESPACE::resampler */
+
+#endif //RESAMPLER_SINC_RESAMPLER_STEREO_H