media/libaaudio/examples/utils/AAudioSimplePlayer.h - third_party/android/platform/frameworks/av - Git at Google

 /*
  * Copyright (C) 2017 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.
  */

 // Play sine waves using an AAudio callback.

 #ifndef AAUDIO_SIMPLE_PLAYER_H
 #define AAUDIO_SIMPLE_PLAYER_H

 #include <sched.h>
 #include <unistd.h>

 #include <aaudio/AAudio.h>
 #include "AAudioArgsParser.h"
 #include "SineGenerator.h"

 //#define SHARING_MODE  AAUDIO_SHARING_MODE_EXCLUSIVE
 #define SHARING_MODE  AAUDIO_SHARING_MODE_SHARED
 #define PERFORMANCE_MODE AAUDIO_PERFORMANCE_MODE_NONE

 // Arbitrary period for glitches
 #define FORCED_UNDERRUN_PERIOD_FRAMES    (2 * 48000)

 #define MAX_TIMESTAMPS                   16

 typedef struct Timestamp {
     int64_t position;
     int64_t nanoseconds;
 } Timestamp;

 /**
  * Simple wrapper for AAudio that opens an output stream either in callback or blocking write mode.
  */
 class AAudioSimplePlayer {
 public:
     AAudioSimplePlayer() {}
     ~AAudioSimplePlayer() {
         close();
     };

     /**
      * Call this before calling open().
      * @param requestedSharingMode
      */
     void setSharingMode(aaudio_sharing_mode_t requestedSharingMode) {
         mRequestedSharingMode = requestedSharingMode;
     }

     /**
      * Call this before calling open().
      * @param requestedPerformanceMode
      */
     void setPerformanceMode(aaudio_performance_mode_t requestedPerformanceMode) {
         mRequestedPerformanceMode = requestedPerformanceMode;
     }

     // TODO Extract a common base class for record and playback.

     /**
      * Only call this after open() has been called.
      */
     int32_t getSampleRate() const {
         if (mStream == nullptr) {
             return AAUDIO_ERROR_INVALID_STATE;
         }
         return AAudioStream_getSampleRate(mStream);
     }

     /**
      * Only call this after open() has been called.
      */
     int32_t getChannelCount() {
         if (mStream == nullptr) {
             return AAUDIO_ERROR_INVALID_STATE;
         }
         return AAudioStream_getChannelCount(mStream);
     }

     /**
      * Open a stream
      */
     aaudio_result_t open(const AAudioParameters &parameters,
                          AAudioStream_dataCallback dataCallback = nullptr,
                          AAudioStream_errorCallback errorCallback = nullptr,
                          void *userContext = nullptr) {
         aaudio_result_t result = AAUDIO_OK;

         // Use an AAudioStreamBuilder to contain requested parameters.
         AAudioStreamBuilder *builder = nullptr;
         result = AAudio_createStreamBuilder(&builder);
         if (result != AAUDIO_OK) return result;

         parameters.applyParameters(builder); // apply args

         AAudioStreamBuilder_setDirection(builder, AAUDIO_DIRECTION_OUTPUT);

         if (dataCallback != nullptr) {
             AAudioStreamBuilder_setDataCallback(builder, dataCallback, userContext);
         }
         if (errorCallback != nullptr) {
             AAudioStreamBuilder_setErrorCallback(builder, errorCallback, userContext);
         }
         //AAudioStreamBuilder_setFramesPerDataCallback(builder, CALLBACK_SIZE_FRAMES);
         //AAudioStreamBuilder_setBufferCapacityInFrames(builder, 48 * 8);

         // Open an AAudioStream using the Builder.
         result = AAudioStreamBuilder_openStream(builder, &mStream);

         if (result == AAUDIO_OK) {
             int32_t sizeInBursts = parameters.getNumberOfBursts();
             int32_t framesPerBurst = AAudioStream_getFramesPerBurst(mStream);
             int32_t bufferSizeFrames = sizeInBursts * framesPerBurst;
             AAudioStream_setBufferSizeInFrames(mStream, bufferSizeFrames);
         }

         AAudioStreamBuilder_delete(builder);
         return result;
     }

     aaudio_result_t open(int channelCount, int sampSampleRate, aaudio_format_t format,
                          AAudioStream_dataCallback dataProc,
                          AAudioStream_errorCallback errorProc,
                          void *userContext) {
         aaudio_result_t result = AAUDIO_OK;

         // Use an AAudioStreamBuilder to contain requested parameters.
         AAudioStreamBuilder *builder = nullptr;
         result = AAudio_createStreamBuilder(&builder);
         if (result != AAUDIO_OK) return result;

         AAudioStreamBuilder_setDirection(builder, AAUDIO_DIRECTION_OUTPUT);
         AAudioStreamBuilder_setPerformanceMode(builder, mRequestedPerformanceMode);
         AAudioStreamBuilder_setSharingMode(builder, mRequestedSharingMode);

         AAudioStreamBuilder_setChannelCount(builder, channelCount);
         AAudioStreamBuilder_setSampleRate(builder, sampSampleRate);
         AAudioStreamBuilder_setFormat(builder, format);

         if (dataProc != nullptr) {
             AAudioStreamBuilder_setDataCallback(builder, dataProc, userContext);
         }
         if (errorProc != nullptr) {
             AAudioStreamBuilder_setErrorCallback(builder, errorProc, userContext);
         }
         //AAudioStreamBuilder_setFramesPerDataCallback(builder, CALLBACK_SIZE_FRAMES);
         //AAudioStreamBuilder_setBufferCapacityInFrames(builder, 48 * 8);

         // Open an AAudioStream using the Builder.
         result = AAudioStreamBuilder_openStream(builder, &mStream);

         AAudioStreamBuilder_delete(builder);

         return result;
     }

     aaudio_result_t close() {
         if (mStream != nullptr) {
             AAudioStream_close(mStream);
             mStream = nullptr;
         }
         return AAUDIO_OK;
     }

     // Write zero data to fill up the buffer and prevent underruns.
     aaudio_result_t prime() {
         int32_t samplesPerFrame = AAudioStream_getChannelCount(mStream);
         const int numFrames = 32;
         float zeros[numFrames * samplesPerFrame];
         memset(zeros, 0, sizeof(zeros));
         aaudio_result_t result = numFrames;
         while (result == numFrames) {
             result = AAudioStream_write(mStream, zeros, numFrames, 0);
         }
         return result;
     }

     // Start the stream. AAudio will start calling your callback function.
      aaudio_result_t start() {
         aaudio_result_t result = AAudioStream_requestStart(mStream);
         if (result != AAUDIO_OK) {
             printf("ERROR - AAudioStream_requestStart(output) returned %d %s\n",
                     result, AAudio_convertResultToText(result));
         }
         return result;
     }

     // Stop the stream. AAudio will stop calling your callback function.
     aaudio_result_t stop() {
         aaudio_result_t result = AAudioStream_requestStop(mStream);
         if (result != AAUDIO_OK) {
             printf("ERROR - AAudioStream_requestStop(output) returned %d %s\n",
                    result, AAudio_convertResultToText(result));
         }
         int32_t xRunCount = AAudioStream_getXRunCount(mStream);
         printf("AAudioStream_getXRunCount %d\n", xRunCount);
         return result;
     }

     // Pause the stream. AAudio will stop calling your callback function.
     aaudio_result_t pause() {
         aaudio_result_t result = AAudioStream_requestPause(mStream);
         if (result != AAUDIO_OK) {
             printf("ERROR - AAudioStream_requestPause(output) returned %d %s\n",
                    result, AAudio_convertResultToText(result));
         }
         int32_t xRunCount = AAudioStream_getXRunCount(mStream);
         printf("AAudioStream_getXRunCount %d\n", xRunCount);
         return result;
     }

     aaudio_result_t waitUntilPaused() {
         aaudio_result_t result = AAUDIO_OK;
         aaudio_stream_state_t currentState = AAudioStream_getState(mStream);
         aaudio_stream_state_t inputState = AAUDIO_STREAM_STATE_PAUSING;
         while (result == AAUDIO_OK && currentState == AAUDIO_STREAM_STATE_PAUSING) {
             result = AAudioStream_waitForStateChange(mStream, inputState,
                                                      &currentState, NANOS_PER_SECOND);
             inputState = currentState;
         }
         if (result != AAUDIO_OK) {
             return result;
         }
         return (currentState == AAUDIO_STREAM_STATE_PAUSED)
                ? AAUDIO_OK : AAUDIO_ERROR_INVALID_STATE;
     }

     // Flush the stream. AAudio will stop calling your callback function.
     aaudio_result_t flush() {
         aaudio_result_t result = AAudioStream_requestFlush(mStream);
         if (result != AAUDIO_OK) {
             printf("ERROR - AAudioStream_requestFlush(output) returned %d %s\n",
                    result, AAudio_convertResultToText(result));
         }
         return result;
     }

     AAudioStream *getStream() const {
         return mStream;
     }

 private:
     AAudioStream             *mStream = nullptr;
     aaudio_sharing_mode_t     mRequestedSharingMode = SHARING_MODE;
     aaudio_performance_mode_t mRequestedPerformanceMode = PERFORMANCE_MODE;

 };

 typedef struct SineThreadedData_s {

     SineGenerator      sineOscillators[MAX_CHANNELS];
     Timestamp          timestamps[MAX_TIMESTAMPS];
     int64_t            framesTotal = 0;
     int64_t            nextFrameToGlitch = FORCED_UNDERRUN_PERIOD_FRAMES;
     int32_t            minNumFrames = INT32_MAX;
     int32_t            maxNumFrames = 0;
     int32_t            timestampCount = 0; // in timestamps
     int32_t            sampleRate = 48000;
     int32_t            prefixToneFrames = 0;
     bool               sweepSetup = false;

     int                scheduler = 0;
     bool               schedulerChecked = false;
     int32_t            hangTimeMSec = 0;

     AAudioSimplePlayer simplePlayer;
     int32_t            callbackCount = 0;
     WakeUp             waker{AAUDIO_OK};

     /**
      * Set sampleRate first.
      */
     void setupSineBlip() {
         for (int i = 0; i < MAX_CHANNELS; ++i) {
             double centerFrequency = 880.0 * (i + 2);
             sineOscillators[i].setup(centerFrequency, sampleRate);
             sineOscillators[i].setSweep(centerFrequency, centerFrequency, 0.0);
         }
     }

     void setupSineSweeps() {
         for (int i = 0; i < MAX_CHANNELS; ++i) {
             double centerFrequency = 220.0 * (i + 2);
             sineOscillators[i].setup(centerFrequency, sampleRate);
             double minFrequency = centerFrequency * 2.0 / 3.0;
             // Change range slightly so they will go out of phase.
             double maxFrequency = centerFrequency * 3.0 / 2.0;
             double sweepSeconds = 5.0 + i;
             sineOscillators[i].setSweep(minFrequency, maxFrequency, sweepSeconds);
         }
         sweepSetup = true;
     }

 } SineThreadedData_t;

 // Callback function that fills the audio output buffer.
 aaudio_data_callback_result_t SimplePlayerDataCallbackProc(
         AAudioStream *stream,
         void *userData,
         void *audioData,
         int32_t numFrames
         ) {

     // should not happen but just in case...
     if (userData == nullptr) {
         printf("ERROR - SimplePlayerDataCallbackProc needs userData\n");
         return AAUDIO_CALLBACK_RESULT_STOP;
     }
     SineThreadedData_t *sineData = (SineThreadedData_t *) userData;

     // Play an initial high tone so we can tell whether the beginning was truncated.
     if (!sineData->sweepSetup && sineData->framesTotal >= sineData->prefixToneFrames) {
         sineData->setupSineSweeps();
     }

     if (sineData->hangTimeMSec > 0) {
         if (sineData->framesTotal > sineData->nextFrameToGlitch) {
             usleep(sineData->hangTimeMSec * 1000);
             printf("Hang callback at %lld frames for %d msec\n",
                     (long long) sineData->framesTotal,
                    sineData->hangTimeMSec);
             sineData->nextFrameToGlitch += FORCED_UNDERRUN_PERIOD_FRAMES;
         }
     }

     if (!sineData->schedulerChecked) {
         sineData->scheduler = sched_getscheduler(gettid());
         sineData->schedulerChecked = true;
     }

     if (sineData->timestampCount < MAX_TIMESTAMPS) {
         Timestamp *timestamp = &sineData->timestamps[sineData->timestampCount];
         aaudio_result_t result = AAudioStream_getTimestamp(stream,
             CLOCK_MONOTONIC, &timestamp->position, &timestamp->nanoseconds);
         if (result == AAUDIO_OK && // valid?
                 (sineData->timestampCount == 0 || // first one?
                 (timestamp->position != (timestamp - 1)->position))) { // advanced position?
             sineData->timestampCount++; // keep this one
         }
     }

     if (numFrames > sineData->maxNumFrames) {
         sineData->maxNumFrames = numFrames;
     }
     if (numFrames < sineData->minNumFrames) {
         sineData->minNumFrames = numFrames;
     }

     int32_t samplesPerFrame = AAudioStream_getChannelCount(stream);


     int numActiveOscilators = (samplesPerFrame > MAX_CHANNELS) ? MAX_CHANNELS : samplesPerFrame;
     switch (AAudioStream_getFormat(stream)) {
         case AAUDIO_FORMAT_PCM_I16: {
             int16_t *audioBuffer = (int16_t *) audioData;
             for (int i = 0; i < numActiveOscilators; ++i) {
                 sineData->sineOscillators[i].render(&audioBuffer[i], samplesPerFrame,
                                                     numFrames);
             }
         }
             break;
         case AAUDIO_FORMAT_PCM_FLOAT: {
             float *audioBuffer = (float *) audioData;
             for (int i = 0; i < numActiveOscilators; ++i) {
                 sineData->sineOscillators[i].render(&audioBuffer[i], samplesPerFrame,
                                                     numFrames);
             }
         }
             break;
         default:
             return AAUDIO_CALLBACK_RESULT_STOP;
     }

     sineData->callbackCount++;
     sineData->framesTotal += numFrames;
     return AAUDIO_CALLBACK_RESULT_CONTINUE;
 }

 void SimplePlayerErrorCallbackProc(
         AAudioStream *stream __unused,
         void *userData __unused,
         aaudio_result_t error) {
     // should not happen but just in case...
     if (userData == nullptr) {
         printf("ERROR - MyPlayerErrorCallbackProc needs userData\n");
         return;
     }
     SineThreadedData_t *sineData = (SineThreadedData_t *) userData;
     android::status_t ret = sineData->waker.wake(error);
     printf("Error Callback, error: %d, futex wake returns %d\n", error, ret);
 }


 #endif //AAUDIO_SIMPLE_PLAYER_H
	/*
	* Copyright (C) 2017 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.
	*/

	// Play sine waves using an AAudio callback.

	#ifndef AAUDIO_SIMPLE_PLAYER_H
	#define AAUDIO_SIMPLE_PLAYER_H

	#include <sched.h>
	#include <unistd.h>

	#include <aaudio/AAudio.h>
	#include "AAudioArgsParser.h"
	#include "SineGenerator.h"

	//#define SHARING_MODE AAUDIO_SHARING_MODE_EXCLUSIVE
	#define SHARING_MODE AAUDIO_SHARING_MODE_SHARED
	#define PERFORMANCE_MODE AAUDIO_PERFORMANCE_MODE_NONE

	// Arbitrary period for glitches
	#define FORCED_UNDERRUN_PERIOD_FRAMES (2 * 48000)

	#define MAX_TIMESTAMPS 16

	typedef struct Timestamp {
	int64_t position;
	int64_t nanoseconds;
	} Timestamp;

	/**
	* Simple wrapper for AAudio that opens an output stream either in callback or blocking write mode.
	*/
	class AAudioSimplePlayer {
	public:
	AAudioSimplePlayer() {}
	~AAudioSimplePlayer() {
	close();
	};

	/**
	* Call this before calling open().
	* @param requestedSharingMode
	*/
	void setSharingMode(aaudio_sharing_mode_t requestedSharingMode) {
	mRequestedSharingMode = requestedSharingMode;
	}

	/**
	* Call this before calling open().
	* @param requestedPerformanceMode
	*/
	void setPerformanceMode(aaudio_performance_mode_t requestedPerformanceMode) {
	mRequestedPerformanceMode = requestedPerformanceMode;
	}

	// TODO Extract a common base class for record and playback.

	/**
	* Only call this after open() has been called.
	*/
	int32_t getSampleRate() const {
	if (mStream == nullptr) {
	return AAUDIO_ERROR_INVALID_STATE;
	}
	return AAudioStream_getSampleRate(mStream);
	}

	/**
	* Only call this after open() has been called.
	*/
	int32_t getChannelCount() {
	if (mStream == nullptr) {
	return AAUDIO_ERROR_INVALID_STATE;
	}
	return AAudioStream_getChannelCount(mStream);
	}

	/**
	* Open a stream
	*/
	aaudio_result_t open(const AAudioParameters &parameters,
	AAudioStream_dataCallback dataCallback = nullptr,
	AAudioStream_errorCallback errorCallback = nullptr,
	void *userContext = nullptr) {
	aaudio_result_t result = AAUDIO_OK;

	// Use an AAudioStreamBuilder to contain requested parameters.
	AAudioStreamBuilder *builder = nullptr;
	result = AAudio_createStreamBuilder(&builder);
	if (result != AAUDIO_OK) return result;

	parameters.applyParameters(builder); // apply args

	AAudioStreamBuilder_setDirection(builder, AAUDIO_DIRECTION_OUTPUT);

	if (dataCallback != nullptr) {
	AAudioStreamBuilder_setDataCallback(builder, dataCallback, userContext);
	}
	if (errorCallback != nullptr) {
	AAudioStreamBuilder_setErrorCallback(builder, errorCallback, userContext);
	}
	//AAudioStreamBuilder_setFramesPerDataCallback(builder, CALLBACK_SIZE_FRAMES);
	//AAudioStreamBuilder_setBufferCapacityInFrames(builder, 48 * 8);

	// Open an AAudioStream using the Builder.
	result = AAudioStreamBuilder_openStream(builder, &mStream);

	if (result == AAUDIO_OK) {
	int32_t sizeInBursts = parameters.getNumberOfBursts();
	int32_t framesPerBurst = AAudioStream_getFramesPerBurst(mStream);
	int32_t bufferSizeFrames = sizeInBursts * framesPerBurst;
	AAudioStream_setBufferSizeInFrames(mStream, bufferSizeFrames);
	}

	AAudioStreamBuilder_delete(builder);
	return result;
	}

	aaudio_result_t open(int channelCount, int sampSampleRate, aaudio_format_t format,
	AAudioStream_dataCallback dataProc,
	AAudioStream_errorCallback errorProc,
	void *userContext) {
	aaudio_result_t result = AAUDIO_OK;

	// Use an AAudioStreamBuilder to contain requested parameters.
	AAudioStreamBuilder *builder = nullptr;
	result = AAudio_createStreamBuilder(&builder);
	if (result != AAUDIO_OK) return result;

	AAudioStreamBuilder_setDirection(builder, AAUDIO_DIRECTION_OUTPUT);
	AAudioStreamBuilder_setPerformanceMode(builder, mRequestedPerformanceMode);
	AAudioStreamBuilder_setSharingMode(builder, mRequestedSharingMode);

	AAudioStreamBuilder_setChannelCount(builder, channelCount);
	AAudioStreamBuilder_setSampleRate(builder, sampSampleRate);
	AAudioStreamBuilder_setFormat(builder, format);

	if (dataProc != nullptr) {
	AAudioStreamBuilder_setDataCallback(builder, dataProc, userContext);
	}
	if (errorProc != nullptr) {
	AAudioStreamBuilder_setErrorCallback(builder, errorProc, userContext);
	}
	//AAudioStreamBuilder_setFramesPerDataCallback(builder, CALLBACK_SIZE_FRAMES);
	//AAudioStreamBuilder_setBufferCapacityInFrames(builder, 48 * 8);

	// Open an AAudioStream using the Builder.
	result = AAudioStreamBuilder_openStream(builder, &mStream);

	AAudioStreamBuilder_delete(builder);

	return result;
	}

	aaudio_result_t close() {
	if (mStream != nullptr) {
	AAudioStream_close(mStream);
	mStream = nullptr;
	}
	return AAUDIO_OK;
	}

	// Write zero data to fill up the buffer and prevent underruns.
	aaudio_result_t prime() {
	int32_t samplesPerFrame = AAudioStream_getChannelCount(mStream);
	const int numFrames = 32;
	float zeros[numFrames * samplesPerFrame];
	memset(zeros, 0, sizeof(zeros));
	aaudio_result_t result = numFrames;
	while (result == numFrames) {
	result = AAudioStream_write(mStream, zeros, numFrames, 0);
	}
	return result;
	}

	// Start the stream. AAudio will start calling your callback function.
	aaudio_result_t start() {
	aaudio_result_t result = AAudioStream_requestStart(mStream);
	if (result != AAUDIO_OK) {
	printf("ERROR - AAudioStream_requestStart(output) returned %d %s\n",
	result, AAudio_convertResultToText(result));
	}
	return result;
	}

	// Stop the stream. AAudio will stop calling your callback function.
	aaudio_result_t stop() {
	aaudio_result_t result = AAudioStream_requestStop(mStream);
	if (result != AAUDIO_OK) {
	printf("ERROR - AAudioStream_requestStop(output) returned %d %s\n",
	result, AAudio_convertResultToText(result));
	}
	int32_t xRunCount = AAudioStream_getXRunCount(mStream);
	printf("AAudioStream_getXRunCount %d\n", xRunCount);
	return result;
	}

	// Pause the stream. AAudio will stop calling your callback function.
	aaudio_result_t pause() {
	aaudio_result_t result = AAudioStream_requestPause(mStream);
	if (result != AAUDIO_OK) {
	printf("ERROR - AAudioStream_requestPause(output) returned %d %s\n",
	result, AAudio_convertResultToText(result));
	}
	int32_t xRunCount = AAudioStream_getXRunCount(mStream);
	printf("AAudioStream_getXRunCount %d\n", xRunCount);
	return result;
	}

	aaudio_result_t waitUntilPaused() {
	aaudio_result_t result = AAUDIO_OK;
	aaudio_stream_state_t currentState = AAudioStream_getState(mStream);
	aaudio_stream_state_t inputState = AAUDIO_STREAM_STATE_PAUSING;
	while (result == AAUDIO_OK && currentState == AAUDIO_STREAM_STATE_PAUSING) {
	result = AAudioStream_waitForStateChange(mStream, inputState,
	&currentState, NANOS_PER_SECOND);
	inputState = currentState;
	}
	if (result != AAUDIO_OK) {
	return result;
	}
	return (currentState == AAUDIO_STREAM_STATE_PAUSED)
	? AAUDIO_OK : AAUDIO_ERROR_INVALID_STATE;
	}

	// Flush the stream. AAudio will stop calling your callback function.
	aaudio_result_t flush() {
	aaudio_result_t result = AAudioStream_requestFlush(mStream);
	if (result != AAUDIO_OK) {
	printf("ERROR - AAudioStream_requestFlush(output) returned %d %s\n",
	result, AAudio_convertResultToText(result));
	}
	return result;
	}

	AAudioStream *getStream() const {
	return mStream;
	}

	private:
	AAudioStream *mStream = nullptr;
	aaudio_sharing_mode_t mRequestedSharingMode = SHARING_MODE;
	aaudio_performance_mode_t mRequestedPerformanceMode = PERFORMANCE_MODE;

	};

	typedef struct SineThreadedData_s {

	SineGenerator sineOscillators[MAX_CHANNELS];
	Timestamp timestamps[MAX_TIMESTAMPS];
	int64_t framesTotal = 0;
	int64_t nextFrameToGlitch = FORCED_UNDERRUN_PERIOD_FRAMES;
	int32_t minNumFrames = INT32_MAX;
	int32_t maxNumFrames = 0;
	int32_t timestampCount = 0; // in timestamps
	int32_t sampleRate = 48000;
	int32_t prefixToneFrames = 0;
	bool sweepSetup = false;

	int scheduler = 0;
	bool schedulerChecked = false;
	int32_t hangTimeMSec = 0;

	AAudioSimplePlayer simplePlayer;
	int32_t callbackCount = 0;
	WakeUp waker{AAUDIO_OK};

	/**
	* Set sampleRate first.
	*/
	void setupSineBlip() {
	for (int i = 0; i < MAX_CHANNELS; ++i) {
	double centerFrequency = 880.0 * (i + 2);
	sineOscillators[i].setup(centerFrequency, sampleRate);
	sineOscillators[i].setSweep(centerFrequency, centerFrequency, 0.0);
	}
	}

	void setupSineSweeps() {
	for (int i = 0; i < MAX_CHANNELS; ++i) {
	double centerFrequency = 220.0 * (i + 2);
	sineOscillators[i].setup(centerFrequency, sampleRate);
	double minFrequency = centerFrequency * 2.0 / 3.0;
	// Change range slightly so they will go out of phase.
	double maxFrequency = centerFrequency * 3.0 / 2.0;
	double sweepSeconds = 5.0 + i;
	sineOscillators[i].setSweep(minFrequency, maxFrequency, sweepSeconds);
	}
	sweepSetup = true;
	}

	} SineThreadedData_t;

	// Callback function that fills the audio output buffer.
	aaudio_data_callback_result_t SimplePlayerDataCallbackProc(
	AAudioStream *stream,
	void *userData,
	void *audioData,
	int32_t numFrames
	) {

	// should not happen but just in case...
	if (userData == nullptr) {
	printf("ERROR - SimplePlayerDataCallbackProc needs userData\n");
	return AAUDIO_CALLBACK_RESULT_STOP;
	}
	SineThreadedData_t sineData = (SineThreadedData_t ) userData;

	// Play an initial high tone so we can tell whether the beginning was truncated.
	if (!sineData->sweepSetup && sineData->framesTotal >= sineData->prefixToneFrames) {
	sineData->setupSineSweeps();
	}

	if (sineData->hangTimeMSec > 0) {
	if (sineData->framesTotal > sineData->nextFrameToGlitch) {
	usleep(sineData->hangTimeMSec * 1000);
	printf("Hang callback at %lld frames for %d msec\n",
	(long long) sineData->framesTotal,
	sineData->hangTimeMSec);
	sineData->nextFrameToGlitch += FORCED_UNDERRUN_PERIOD_FRAMES;
	}
	}

	if (!sineData->schedulerChecked) {
	sineData->scheduler = sched_getscheduler(gettid());
	sineData->schedulerChecked = true;
	}

	if (sineData->timestampCount < MAX_TIMESTAMPS) {
	Timestamp *timestamp = &sineData->timestamps[sineData->timestampCount];
	aaudio_result_t result = AAudioStream_getTimestamp(stream,
	CLOCK_MONOTONIC, &timestamp->position, &timestamp->nanoseconds);
	if (result == AAUDIO_OK && // valid?
	(sineData->timestampCount == 0 \|\| // first one?
	(timestamp->position != (timestamp - 1)->position))) { // advanced position?
	sineData->timestampCount++; // keep this one
	}
	}

	if (numFrames > sineData->maxNumFrames) {
	sineData->maxNumFrames = numFrames;
	}
	if (numFrames < sineData->minNumFrames) {
	sineData->minNumFrames = numFrames;
	}

	int32_t samplesPerFrame = AAudioStream_getChannelCount(stream);


	int numActiveOscilators = (samplesPerFrame > MAX_CHANNELS) ? MAX_CHANNELS : samplesPerFrame;
	switch (AAudioStream_getFormat(stream)) {
	case AAUDIO_FORMAT_PCM_I16: {
	int16_t audioBuffer = (int16_t ) audioData;
	for (int i = 0; i < numActiveOscilators; ++i) {
	sineData->sineOscillators[i].render(&audioBuffer[i], samplesPerFrame,
	numFrames);
	}
	}
	break;
	case AAUDIO_FORMAT_PCM_FLOAT: {
	float audioBuffer = (float ) audioData;
	for (int i = 0; i < numActiveOscilators; ++i) {
	sineData->sineOscillators[i].render(&audioBuffer[i], samplesPerFrame,
	numFrames);
	}
	}
	break;
	default:
	return AAUDIO_CALLBACK_RESULT_STOP;
	}

	sineData->callbackCount++;
	sineData->framesTotal += numFrames;
	return AAUDIO_CALLBACK_RESULT_CONTINUE;
	}

	void SimplePlayerErrorCallbackProc(
	AAudioStream *stream __unused,
	void *userData __unused,
	aaudio_result_t error) {
	// should not happen but just in case...
	if (userData == nullptr) {
	printf("ERROR - MyPlayerErrorCallbackProc needs userData\n");
	return;
	}
	SineThreadedData_t sineData = (SineThreadedData_t ) userData;
	android::status_t ret = sineData->waker.wake(error);
	printf("Error Callback, error: %d, futex wake returns %d\n", error, ret);
	}


	#endif //AAUDIO_SIMPLE_PLAYER_H