implement SkAudioPLayer for Android

move SkAudioPlayer for Android to proper module
refine playback features for the Android AudioPlayer

Change-Id: I1906c3b3ef91fa4173f66c2c068dc40a3cf824ca
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/319037
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Jorge Betancourt <jmbetancourt@google.com>

BUILD.gn

@@ -2353,7 +2353,6 @@ if (skia_enable_tools) {
         ":skia",
         "modules/skottie",
         "modules/sksg:samples",
-        "//third_party/oboe",
       ]
     }
   }

modules/audioplayer/BUILD.gn

@@ -19,6 +19,10 @@ component("audioplayer") {
       "sfml-system",
       "sfml-audio",
     ]
+  } else if (is_android) {
+    sources += [ "SkAudioPlayer_oboe.cpp" ]
+    deps += [ "../../third_party/oboe" ]
+    libs = [ "OpenSLES" ]
   } else {
     sources += [ "SkAudioPlayer_none.cpp" ]
   }

modules/audioplayer/SkAudioPlayer_oboe.cpp

@@ -0,0 +1,119 @@
+/*
+* Copyright 2020 Google Inc.
+*
+* Use of this source code is governed by a BSD-style license that can be
+* found in the LICENSE file.
+*/
+
+#include "modules/audioplayer/SkAudioPlayer.h"
+
+#include "include/core/SkData.h"
+#include "oboe/Oboe.h"
+#include "stream/MemInputStream.h"
+#include "wav/WavStreamReader.h"
+
+namespace {
+
+class OboeAudioPlayer final : public SkAudioPlayer, oboe::AudioStreamCallback {
+public:
+    explicit OboeAudioPlayer(sk_sp<SkData> data)
+        : fData(std::move(data))
+        , fMemInputStream(const_cast<unsigned char *>
+          (static_cast<const unsigned char *>(fData->data())), static_cast<int32_t>(fData->size()))
+    {
+      // wrap data in MemInputStream to parse WAV header
+      fReader = std::make_unique<parselib::WavStreamReader>(&fMemInputStream);
+      fReader->parse();
+      // set member variables and builder properties using reader
+      fNumSampleFrames = fReader->getNumSampleFrames();
+
+      oboe::AudioStreamBuilder builder;
+      builder.setPerformanceMode(oboe::PerformanceMode::LowLatency);
+      builder.setSharingMode(oboe::SharingMode::Exclusive);
+      builder.setSampleRate(fReader->getSampleRate());
+      builder.setChannelCount(fReader->getNumChannels());
+      builder.setCallback(this);
+      builder.setFormat(oboe::AudioFormat::Float);
+
+      // open the stream (must manually close it when done)
+      fStream = nullptr;
+      builder.openStream(fStream);
+    }
+
+private:
+    oboe::DataCallbackResult
+    onAudioReady(oboe::AudioStream *oboeStream, void *audioData, int32_t numFrames) override {
+        // we assume float samples here
+        float *outBuffer = static_cast<float *>(audioData);
+            int framesRead = fReader->getDataFloat(outBuffer, numFrames);
+            fReadFrameIndex += framesRead;
+            int remainingFrames = numFrames - framesRead;
+            if (remainingFrames > 0) {
+                if (fIsLooping) {
+                    // handle wrap around
+                    fReader->positionToAudio();
+                    fReader->getDataFloat(&outBuffer[framesRead * fReader->getNumChannels()],
+                                         remainingFrames);
+                    fReadFrameIndex += remainingFrames;
+                } else {
+                    // render silence for rest
+                    renderSilence(&outBuffer[framesRead * fReader->getNumChannels()], remainingFrames);
+                    return oboe::DataCallbackResult::Stop;
+                }
+            }
+        return oboe::DataCallbackResult::Continue;
+    }
+
+    void renderSilence(float *start, int numFrames) {
+        for (int i = 0; i < numFrames * fReader->getNumChannels(); ++i) {
+            start[i] = 0;
+        }
+    }
+    double onGetDuration() const override {
+        return fNumSampleFrames * fStream->getChannelCount() / fStream->getSampleRate();
+    }
+
+    double onGetTime() const override {
+        return (fReadFrameIndex * fStream->getChannelCount()) / fStream->getSampleRate();
+    }
+
+    double onSetTime(double t) override {
+        fReadFrameIndex = (t * fStream->getSampleRate()) / fStream->getChannelCount();
+        return onGetTime();
+    }
+
+    State onSetState(State state) override {
+        switch (state) {
+            case State::kPlaying: fStream->start();  break;
+            case State::kStopped: fStream->close();  break;
+            case State::kPaused : fStream->pause(); break;
+        }
+
+        return state;
+    }
+
+
+    // TODO: implement rate function (change sample rate of AudioStream)
+    float onSetRate(float r) override {
+        return r;
+    }
+
+    // TODO: implement volume function (multiply each sample by desired amplitude)
+    float onSetVolume(float v) override {
+        return v;
+    }
+
+    const sk_sp<SkData>                         fData;
+    std::shared_ptr<oboe::AudioStream>          fStream;
+    std::unique_ptr<parselib::WavStreamReader>  fReader;
+    parselib::MemInputStream                    fMemInputStream;
+    int32_t                                     fReadFrameIndex {0};
+    int                                         fNumSampleFrames;
+    bool                                        fIsLooping {false};
+};
+
+} // namespace
+
+std::unique_ptr<SkAudioPlayer> SkAudioPlayer::Make(sk_sp<SkData> src) {
+    return std::unique_ptr<SkAudioPlayer>(new OboeAudioPlayer(std::move(src)));
+}

third_party/oboe/BUILD.gn

@@ -9,6 +9,7 @@ third_party("oboe") {
   public_include_dirs = [
     "../externals/oboe/include",
     "../externals/oboe/samples/parselib/src/main/cpp",
+    "../externals/oboe/src/flowgraph",
   ]
   include_dirs = [ "../externals/oboe/src" ]
 
@@ -43,10 +44,12 @@ third_party("oboe") {
     "../externals/oboe/src/fifo/FifoController.cpp",
     "../externals/oboe/src/fifo/FifoControllerBase.cpp",
     "../externals/oboe/src/fifo/FifoControllerIndirect.cpp",
+    "../externals/oboe/src/flowgraph/ChannelCountConverter.cpp",
     "../externals/oboe/src/flowgraph/ClipToRange.cpp",
     "../externals/oboe/src/flowgraph/FlowGraphNode.cpp",
     "../externals/oboe/src/flowgraph/ManyToMultiConverter.cpp",
     "../externals/oboe/src/flowgraph/MonoToMultiConverter.cpp",
+    "../externals/oboe/src/flowgraph/MultiToMonoConverter.cpp",
     "../externals/oboe/src/flowgraph/RampLinear.cpp",
     "../externals/oboe/src/flowgraph/SampleRateConverter.cpp",
     "../externals/oboe/src/flowgraph/SinkFloat.cpp",