media/libaaudio/src/utility/AAudioUtilities.h - third_party/android/platform/frameworks/av - Git at Google

 /*
  * Copyright 2016 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.
  */

 #ifndef UTILITY_AAUDIO_UTILITIES_H
 #define UTILITY_AAUDIO_UTILITIES_H

 #include <algorithm>
 #include <functional>
 #include <stdint.h>
 #include <sys/types.h>

 #include <utils/Errors.h>
 #include <hardware/audio.h>

 #include "aaudio/AAudio.h"

 /**
  * Convert an AAudio result into the closest matching Android status.
  */
 android::status_t AAudioConvert_aaudioToAndroidStatus(aaudio_result_t result);

 /**
  * Convert an Android status into the closest matching AAudio result.
  */
 aaudio_result_t AAudioConvert_androidToAAudioResult(android::status_t status);

 /**
  * Convert an array of floats to an array of int16_t.
  *
  * @param source
  * @param destination
  * @param numSamples number of values in the array
  * @param amplitude level between 0.0 and 1.0
  */
 void AAudioConvert_floatToPcm16(const float *source,
                                 int16_t *destination,
                                 int32_t numSamples,
                                 float amplitude);

 /**
  * Convert floats to int16_t and scale by a linear ramp.
  *
  * The ramp stops just short of reaching amplitude2 so that the next
  * ramp can start at amplitude2 without causing a discontinuity.
  *
  * @param source
  * @param destination
  * @param numFrames
  * @param samplesPerFrame AKA number of channels
  * @param amplitude1 level at start of ramp, between 0.0 and 1.0
  * @param amplitude2 level past end of ramp, between 0.0 and 1.0
  */
 void AAudioConvert_floatToPcm16(const float *source,
                                 int16_t *destination,
                                 int32_t numFrames,
                                 int32_t samplesPerFrame,
                                 float amplitude1,
                                 float amplitude2);

 /**
  * Convert int16_t array to float array ranging from -1.0 to +1.0.
  * @param source
  * @param destination
  * @param numSamples
  */
 //void AAudioConvert_pcm16ToFloat(const int16_t *source, int32_t numSamples,
 //                                float *destination);

 /**
  *
  * Convert int16_t array to float array ranging from +/- amplitude.
  * @param source
  * @param destination
  * @param numSamples
  * @param amplitude
  */
 void AAudioConvert_pcm16ToFloat(const int16_t *source,
                                 float *destination,
                                 int32_t numSamples,
                                 float amplitude);

 /**
  * Convert floats to int16_t and scale by a linear ramp.
  *
  * The ramp stops just short of reaching amplitude2 so that the next
  * ramp can start at amplitude2 without causing a discontinuity.
  *
  * @param source
  * @param destination
  * @param numFrames
  * @param samplesPerFrame AKA number of channels
  * @param amplitude1 level at start of ramp, between 0.0 and 1.0
  * @param amplitude2 level at end of ramp, between 0.0 and 1.0
  */
 void AAudioConvert_pcm16ToFloat(const int16_t *source,
                                 float *destination,
                                 int32_t numFrames,
                                 int32_t samplesPerFrame,
                                 float amplitude1,
                                 float amplitude2);

 /**
  * Scale floats by a linear ramp.
  *
  * The ramp stops just short of reaching amplitude2 so that the next
  * ramp can start at amplitude2 without causing a discontinuity.
  *
  * @param source
  * @param destination
  * @param numFrames
  * @param samplesPerFrame
  * @param amplitude1
  * @param amplitude2
  */
 void AAudio_linearRamp(const float *source,
                        float *destination,
                        int32_t numFrames,
                        int32_t samplesPerFrame,
                        float amplitude1,
                        float amplitude2);

 /**
  * Scale int16_t's by a linear ramp.
  *
  * The ramp stops just short of reaching amplitude2 so that the next
  * ramp can start at amplitude2 without causing a discontinuity.
  *
  * @param source
  * @param destination
  * @param numFrames
  * @param samplesPerFrame
  * @param amplitude1
  * @param amplitude2
  */
 void AAudio_linearRamp(const int16_t *source,
                        int16_t *destination,
                        int32_t numFrames,
                        int32_t samplesPerFrame,
                        float amplitude1,
                        float amplitude2);

 /**
  * Calculate the number of bytes and prevent numeric overflow.
  * @param numFrames frame count
  * @param bytesPerFrame size of a frame in bytes
  * @param sizeInBytes total size in bytes
  * @return AAUDIO_OK or negative error, eg. AAUDIO_ERROR_OUT_OF_RANGE
  */
 int32_t AAudioConvert_framesToBytes(int32_t numFrames,
                                             int32_t bytesPerFrame,
                                             int32_t *sizeInBytes);

 audio_format_t AAudioConvert_aaudioToAndroidDataFormat(aaudio_format_t aaudio_format);

 aaudio_format_t AAudioConvert_androidToAAudioDataFormat(audio_format_t format);

 /**
  * @return the size of a sample of the given format in bytes or AAUDIO_ERROR_ILLEGAL_ARGUMENT
  */
 int32_t AAudioConvert_formatToSizeInBytes(aaudio_format_t format);


 // Note that this code may be replaced by Settings or by some other system configuration tool.

 #define AAUDIO_PROP_MMAP_POLICY           "aaudio.mmap_policy"

 /**
  * Read system property.
  * @return AAUDIO_UNSPECIFIED, AAUDIO_POLICY_NEVER or AAUDIO_POLICY_AUTO or AAUDIO_POLICY_ALWAYS
  */
 int32_t AAudioProperty_getMMapPolicy();

 #define AAUDIO_PROP_MMAP_EXCLUSIVE_POLICY "aaudio.mmap_exclusive_policy"

 /**
  * Read system property.
  * @return AAUDIO_UNSPECIFIED, AAUDIO_POLICY_NEVER or AAUDIO_POLICY_AUTO or AAUDIO_POLICY_ALWAYS
  */
 int32_t AAudioProperty_getMMapExclusivePolicy();

 #define AAUDIO_PROP_MIXER_BURSTS           "aaudio.mixer_bursts"

 /**
  * Read system property.
  * @return number of bursts per AAudio service mixer cycle
  */
 int32_t AAudioProperty_getMixerBursts();

 #define AAUDIO_PROP_HW_BURST_MIN_USEC      "aaudio.hw_burst_min_usec"

 /**
  * Read a system property that specifies the number of extra microseconds that a thread
  * should sleep when waiting for another thread to service a FIFO. This is used
  * to avoid the waking thread from being overly optimistic about the other threads
  * wakeup timing. This value should be set high enough to cover typical scheduling jitter
  * for a real-time thread.
  *
  * @return number of microseconds to delay the wakeup.
  */
 int32_t AAudioProperty_getWakeupDelayMicros();

 #define AAUDIO_PROP_WAKEUP_DELAY_USEC      "aaudio.wakeup_delay_usec"

 /**
  * Read a system property that specifies the minimum sleep time when polling the FIFO.
  *
  * @return minimum number of microseconds to sleep.
  */
 int32_t AAudioProperty_getMinimumSleepMicros();

 #define AAUDIO_PROP_MINIMUM_SLEEP_USEC      "aaudio.minimum_sleep_usec"

 /**
  * Read system property.
  * This is handy in case the DMA is bursting too quickly for the CPU to keep up.
  * For example, there may be a DMA burst every 100 usec but you only
  * want to feed the MMAP buffer every 2000 usec.
  *
  * This will affect the framesPerBurst for an MMAP stream.
  *
  * @return minimum number of microseconds for a MMAP HW burst
  */
 int32_t AAudioProperty_getHardwareBurstMinMicros();

 /**
  * Try a function f until it returns true.
  *
  * The function is always called at least once.
  *
  * @param f the function to evaluate, which returns a bool.
  * @param times the number of times to evaluate f.
  * @param sleepMs the sleep time per check of f, if greater than 0.
  * @return true if f() eventually returns true.
  */
 static inline bool AAudio_tryUntilTrue(
         std::function<bool()> f, int times, int sleepMs) {
     static const useconds_t US_PER_MS = 1000;

     sleepMs = std::max(sleepMs, 0);
     for (;;) {
         if (f()) return true;
         if (times <= 1) return false;
         --times;
         usleep(sleepMs * US_PER_MS);
     }
 }

 #endif //UTILITY_AAUDIO_UTILITIES_H
	/*
	* Copyright 2016 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.
	*/

	#ifndef UTILITY_AAUDIO_UTILITIES_H
	#define UTILITY_AAUDIO_UTILITIES_H

	#include <algorithm>
	#include <functional>
	#include <stdint.h>
	#include <sys/types.h>

	#include <utils/Errors.h>
	#include <hardware/audio.h>

	#include "aaudio/AAudio.h"

	/**
	* Convert an AAudio result into the closest matching Android status.
	*/
	android::status_t AAudioConvert_aaudioToAndroidStatus(aaudio_result_t result);

	/**
	* Convert an Android status into the closest matching AAudio result.
	*/
	aaudio_result_t AAudioConvert_androidToAAudioResult(android::status_t status);

	/**
	* Convert an array of floats to an array of int16_t.
	*
	* @param source
	* @param destination
	* @param numSamples number of values in the array
	* @param amplitude level between 0.0 and 1.0
	*/
	void AAudioConvert_floatToPcm16(const float *source,
	int16_t *destination,
	int32_t numSamples,
	float amplitude);

	/**
	* Convert floats to int16_t and scale by a linear ramp.
	*
	* The ramp stops just short of reaching amplitude2 so that the next
	* ramp can start at amplitude2 without causing a discontinuity.
	*
	* @param source
	* @param destination
	* @param numFrames
	* @param samplesPerFrame AKA number of channels
	* @param amplitude1 level at start of ramp, between 0.0 and 1.0
	* @param amplitude2 level past end of ramp, between 0.0 and 1.0
	*/
	void AAudioConvert_floatToPcm16(const float *source,
	int16_t *destination,
	int32_t numFrames,
	int32_t samplesPerFrame,
	float amplitude1,
	float amplitude2);

	/**
	* Convert int16_t array to float array ranging from -1.0 to +1.0.
	* @param source
	* @param destination
	* @param numSamples
	*/
	//void AAudioConvert_pcm16ToFloat(const int16_t *source, int32_t numSamples,
	// float *destination);

	/**
	*
	* Convert int16_t array to float array ranging from +/- amplitude.
	* @param source
	* @param destination
	* @param numSamples
	* @param amplitude
	*/
	void AAudioConvert_pcm16ToFloat(const int16_t *source,
	float *destination,
	int32_t numSamples,
	float amplitude);

	/**
	* Convert floats to int16_t and scale by a linear ramp.
	*
	* The ramp stops just short of reaching amplitude2 so that the next
	* ramp can start at amplitude2 without causing a discontinuity.
	*
	* @param source
	* @param destination
	* @param numFrames
	* @param samplesPerFrame AKA number of channels
	* @param amplitude1 level at start of ramp, between 0.0 and 1.0
	* @param amplitude2 level at end of ramp, between 0.0 and 1.0
	*/
	void AAudioConvert_pcm16ToFloat(const int16_t *source,
	float *destination,
	int32_t numFrames,
	int32_t samplesPerFrame,
	float amplitude1,
	float amplitude2);

	/**
	* Scale floats by a linear ramp.
	*
	* The ramp stops just short of reaching amplitude2 so that the next
	* ramp can start at amplitude2 without causing a discontinuity.
	*
	* @param source
	* @param destination
	* @param numFrames
	* @param samplesPerFrame
	* @param amplitude1
	* @param amplitude2
	*/
	void AAudio_linearRamp(const float *source,
	float *destination,
	int32_t numFrames,
	int32_t samplesPerFrame,
	float amplitude1,
	float amplitude2);

	/**
	* Scale int16_t's by a linear ramp.
	*
	* The ramp stops just short of reaching amplitude2 so that the next
	* ramp can start at amplitude2 without causing a discontinuity.
	*
	* @param source
	* @param destination
	* @param numFrames
	* @param samplesPerFrame
	* @param amplitude1
	* @param amplitude2
	*/
	void AAudio_linearRamp(const int16_t *source,
	int16_t *destination,
	int32_t numFrames,
	int32_t samplesPerFrame,
	float amplitude1,
	float amplitude2);

	/**
	* Calculate the number of bytes and prevent numeric overflow.
	* @param numFrames frame count
	* @param bytesPerFrame size of a frame in bytes
	* @param sizeInBytes total size in bytes
	* @return AAUDIO_OK or negative error, eg. AAUDIO_ERROR_OUT_OF_RANGE
	*/
	int32_t AAudioConvert_framesToBytes(int32_t numFrames,
	int32_t bytesPerFrame,
	int32_t *sizeInBytes);

	audio_format_t AAudioConvert_aaudioToAndroidDataFormat(aaudio_format_t aaudio_format);

	aaudio_format_t AAudioConvert_androidToAAudioDataFormat(audio_format_t format);

	/**
	* @return the size of a sample of the given format in bytes or AAUDIO_ERROR_ILLEGAL_ARGUMENT
	*/
	int32_t AAudioConvert_formatToSizeInBytes(aaudio_format_t format);


	// Note that this code may be replaced by Settings or by some other system configuration tool.

	#define AAUDIO_PROP_MMAP_POLICY "aaudio.mmap_policy"

	/**
	* Read system property.
	* @return AAUDIO_UNSPECIFIED, AAUDIO_POLICY_NEVER or AAUDIO_POLICY_AUTO or AAUDIO_POLICY_ALWAYS
	*/
	int32_t AAudioProperty_getMMapPolicy();

	#define AAUDIO_PROP_MMAP_EXCLUSIVE_POLICY "aaudio.mmap_exclusive_policy"

	/**
	* Read system property.
	* @return AAUDIO_UNSPECIFIED, AAUDIO_POLICY_NEVER or AAUDIO_POLICY_AUTO or AAUDIO_POLICY_ALWAYS
	*/
	int32_t AAudioProperty_getMMapExclusivePolicy();

	#define AAUDIO_PROP_MIXER_BURSTS "aaudio.mixer_bursts"

	/**
	* Read system property.
	* @return number of bursts per AAudio service mixer cycle
	*/
	int32_t AAudioProperty_getMixerBursts();

	#define AAUDIO_PROP_HW_BURST_MIN_USEC "aaudio.hw_burst_min_usec"

	/**
	* Read a system property that specifies the number of extra microseconds that a thread
	* should sleep when waiting for another thread to service a FIFO. This is used
	* to avoid the waking thread from being overly optimistic about the other threads
	* wakeup timing. This value should be set high enough to cover typical scheduling jitter
	* for a real-time thread.
	*
	* @return number of microseconds to delay the wakeup.
	*/
	int32_t AAudioProperty_getWakeupDelayMicros();

	#define AAUDIO_PROP_WAKEUP_DELAY_USEC "aaudio.wakeup_delay_usec"

	/**
	* Read a system property that specifies the minimum sleep time when polling the FIFO.
	*
	* @return minimum number of microseconds to sleep.
	*/
	int32_t AAudioProperty_getMinimumSleepMicros();

	#define AAUDIO_PROP_MINIMUM_SLEEP_USEC "aaudio.minimum_sleep_usec"

	/**
	* Read system property.
	* This is handy in case the DMA is bursting too quickly for the CPU to keep up.
	* For example, there may be a DMA burst every 100 usec but you only
	* want to feed the MMAP buffer every 2000 usec.
	*
	* This will affect the framesPerBurst for an MMAP stream.
	*
	* @return minimum number of microseconds for a MMAP HW burst
	*/
	int32_t AAudioProperty_getHardwareBurstMinMicros();

	/**
	* Try a function f until it returns true.
	*
	* The function is always called at least once.
	*
	* @param f the function to evaluate, which returns a bool.
	* @param times the number of times to evaluate f.
	* @param sleepMs the sleep time per check of f, if greater than 0.
	* @return true if f() eventually returns true.
	*/
	static inline bool AAudio_tryUntilTrue(
	std::function<bool()> f, int times, int sleepMs) {
	static const useconds_t US_PER_MS = 1000;

	sleepMs = std::max(sleepMs, 0);
	for (;;) {
	if (f()) return true;
	if (times <= 1) return false;
	--times;
	usleep(sleepMs * US_PER_MS);
	}
	}

	#endif //UTILITY_AAUDIO_UTILITIES_H