| /* |
| * Copyright (C) 2007 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 ANDROID_AUDIOTRACK_H |
| #define ANDROID_AUDIOTRACK_H |
| |
| #include <stdint.h> |
| #include <sys/types.h> |
| |
| #include <media/IAudioFlinger.h> |
| #include <media/IAudioTrack.h> |
| #include <media/AudioSystem.h> |
| |
| #include <utils/RefBase.h> |
| #include <utils/Errors.h> |
| #include <binder/IInterface.h> |
| #include <binder/IMemory.h> |
| #include <utils/threads.h> |
| |
| |
| namespace android { |
| |
| // ---------------------------------------------------------------------------- |
| |
| class audio_track_cblk_t; |
| |
| // ---------------------------------------------------------------------------- |
| |
| class AudioTrack |
| { |
| public: |
| enum channel_index { |
| MONO = 0, |
| LEFT = 0, |
| RIGHT = 1 |
| }; |
| |
| /* Events used by AudioTrack callback function (audio_track_cblk_t). |
| */ |
| enum event_type { |
| EVENT_MORE_DATA = 0, // Request to write more data to PCM buffer. |
| EVENT_UNDERRUN = 1, // PCM buffer underrun occured. |
| EVENT_LOOP_END = 2, // Sample loop end was reached; playback restarted from loop start if loop count was not 0. |
| EVENT_MARKER = 3, // Playback head is at the specified marker position (See setMarkerPosition()). |
| EVENT_NEW_POS = 4, // Playback head is at a new position (See setPositionUpdatePeriod()). |
| EVENT_BUFFER_END = 5 // Playback head is at the end of the buffer. |
| }; |
| |
| /* Create Buffer on the stack and pass it to obtainBuffer() |
| * and releaseBuffer(). |
| */ |
| |
| class Buffer |
| { |
| public: |
| enum { |
| MUTE = 0x00000001 |
| }; |
| uint32_t flags; |
| int channelCount; |
| int format; |
| size_t frameCount; |
| size_t size; |
| union { |
| void* raw; |
| short* i16; |
| int8_t* i8; |
| }; |
| }; |
| |
| |
| /* As a convenience, if a callback is supplied, a handler thread |
| * is automatically created with the appropriate priority. This thread |
| * invokes the callback when a new buffer becomes availlable or an underrun condition occurs. |
| * Parameters: |
| * |
| * event: type of event notified (see enum AudioTrack::event_type). |
| * user: Pointer to context for use by the callback receiver. |
| * info: Pointer to optional parameter according to event type: |
| * - EVENT_MORE_DATA: pointer to AudioTrack::Buffer struct. The callback must not write |
| * more bytes than indicated by 'size' field and update 'size' if less bytes are |
| * written. |
| * - EVENT_UNDERRUN: unused. |
| * - EVENT_LOOP_END: pointer to an int indicating the number of loops remaining. |
| * - EVENT_MARKER: pointer to an uin32_t containing the marker position in frames. |
| * - EVENT_NEW_POS: pointer to an uin32_t containing the new position in frames. |
| * - EVENT_BUFFER_END: unused. |
| */ |
| |
| typedef void (*callback_t)(int event, void* user, void *info); |
| |
| /* Constructs an uninitialized AudioTrack. No connection with |
| * AudioFlinger takes place. |
| */ |
| AudioTrack(); |
| |
| /* Creates an audio track and registers it with AudioFlinger. |
| * Once created, the track needs to be started before it can be used. |
| * Unspecified values are set to the audio hardware's current |
| * values. |
| * |
| * Parameters: |
| * |
| * streamType: Select the type of audio stream this track is attached to |
| * (e.g. AudioSystem::MUSIC). |
| * sampleRate: Track sampling rate in Hz. |
| * format: Audio format (e.g AudioSystem::PCM_16_BIT for signed |
| * 16 bits per sample). |
| * channels: Channel mask: see AudioSystem::audio_channels. |
| * frameCount: Total size of track PCM buffer in frames. This defines the |
| * latency of the track. |
| * flags: Reserved for future use. |
| * cbf: Callback function. If not null, this function is called periodically |
| * to request new PCM data. |
| * notificationFrames: The callback function is called each time notificationFrames PCM |
| * frames have been comsumed from track input buffer. |
| * user Context for use by the callback receiver. |
| */ |
| |
| AudioTrack( int streamType, |
| uint32_t sampleRate = 0, |
| int format = 0, |
| int channels = 0, |
| int frameCount = 0, |
| uint32_t flags = 0, |
| callback_t cbf = 0, |
| void* user = 0, |
| int notificationFrames = 0); |
| |
| /* Creates an audio track and registers it with AudioFlinger. With this constructor, |
| * The PCM data to be rendered by AudioTrack is passed in a shared memory buffer |
| * identified by the argument sharedBuffer. This prototype is for static buffer playback. |
| * PCM data must be present into memory before the AudioTrack is started. |
| * The Write() and Flush() methods are not supported in this case. |
| * It is recommented to pass a callback function to be notified of playback end by an |
| * EVENT_UNDERRUN event. |
| */ |
| |
| AudioTrack( int streamType, |
| uint32_t sampleRate = 0, |
| int format = 0, |
| int channels = 0, |
| const sp<IMemory>& sharedBuffer = 0, |
| uint32_t flags = 0, |
| callback_t cbf = 0, |
| void* user = 0, |
| int notificationFrames = 0); |
| |
| /* Terminates the AudioTrack and unregisters it from AudioFlinger. |
| * Also destroys all resources assotiated with the AudioTrack. |
| */ |
| ~AudioTrack(); |
| |
| |
| /* Initialize an uninitialized AudioTrack. |
| * Returned status (from utils/Errors.h) can be: |
| * - NO_ERROR: successful intialization |
| * - INVALID_OPERATION: AudioTrack is already intitialized |
| * - BAD_VALUE: invalid parameter (channels, format, sampleRate...) |
| * - NO_INIT: audio server or audio hardware not initialized |
| * */ |
| status_t set(int streamType =-1, |
| uint32_t sampleRate = 0, |
| int format = 0, |
| int channels = 0, |
| int frameCount = 0, |
| uint32_t flags = 0, |
| callback_t cbf = 0, |
| void* user = 0, |
| int notificationFrames = 0, |
| const sp<IMemory>& sharedBuffer = 0, |
| bool threadCanCallJava = false); |
| |
| |
| /* Result of constructing the AudioTrack. This must be checked |
| * before using any AudioTrack API (except for set()), using |
| * an uninitialized AudioTrack produces undefined results. |
| * See set() method above for possible return codes. |
| */ |
| status_t initCheck() const; |
| |
| /* Returns this track's latency in milliseconds. |
| * This includes the latency due to AudioTrack buffer size, AudioMixer (if any) |
| * and audio hardware driver. |
| */ |
| uint32_t latency() const; |
| |
| /* getters, see constructor */ |
| |
| int streamType() const; |
| int format() const; |
| int channelCount() const; |
| uint32_t frameCount() const; |
| int frameSize() const; |
| sp<IMemory>& sharedBuffer(); |
| |
| |
| /* After it's created the track is not active. Call start() to |
| * make it active. If set, the callback will start being called. |
| */ |
| void start(); |
| |
| /* Stop a track. If set, the callback will cease being called and |
| * obtainBuffer returns STOPPED. Note that obtainBuffer() still works |
| * and will fill up buffers until the pool is exhausted. |
| */ |
| void stop(); |
| bool stopped() const; |
| |
| /* flush a stopped track. All pending buffers are discarded. |
| * This function has no effect if the track is not stoped. |
| */ |
| void flush(); |
| |
| /* Pause a track. If set, the callback will cease being called and |
| * obtainBuffer returns STOPPED. Note that obtainBuffer() still works |
| * and will fill up buffers until the pool is exhausted. |
| */ |
| void pause(); |
| |
| /* mute or unmutes this track. |
| * While mutted, the callback, if set, is still called. |
| */ |
| void mute(bool); |
| bool muted() const; |
| |
| |
| /* set volume for this track, mostly used for games' sound effects |
| */ |
| void setVolume(float left, float right); |
| void getVolume(float* left, float* right); |
| |
| /* set sample rate for this track, mostly used for games' sound effects |
| */ |
| status_t setSampleRate(int sampleRate); |
| uint32_t getSampleRate(); |
| |
| /* Enables looping and sets the start and end points of looping. |
| * |
| * Parameters: |
| * |
| * loopStart: loop start expressed as the number of PCM frames played since AudioTrack start. |
| * loopEnd: loop end expressed as the number of PCM frames played since AudioTrack start. |
| * loopCount: number of loops to execute. Calling setLoop() with loopCount == 0 cancels any pending or |
| * active loop. loopCount = -1 means infinite looping. |
| * |
| * For proper operation the following condition must be respected: |
| * (loopEnd-loopStart) <= framecount() |
| */ |
| status_t setLoop(uint32_t loopStart, uint32_t loopEnd, int loopCount); |
| status_t getLoop(uint32_t *loopStart, uint32_t *loopEnd, int *loopCount); |
| |
| |
| /* Sets marker position. When playback reaches the number of frames specified, a callback with event |
| * type EVENT_MARKER is called. Calling setMarkerPosition with marker == 0 cancels marker notification |
| * callback. |
| * If the AudioTrack has been opened with no callback function associated, the operation will fail. |
| * |
| * Parameters: |
| * |
| * marker: marker position expressed in frames. |
| * |
| * Returned status (from utils/Errors.h) can be: |
| * - NO_ERROR: successful operation |
| * - INVALID_OPERATION: the AudioTrack has no callback installed. |
| */ |
| status_t setMarkerPosition(uint32_t marker); |
| status_t getMarkerPosition(uint32_t *marker); |
| |
| |
| /* Sets position update period. Every time the number of frames specified has been played, |
| * a callback with event type EVENT_NEW_POS is called. |
| * Calling setPositionUpdatePeriod with updatePeriod == 0 cancels new position notification |
| * callback. |
| * If the AudioTrack has been opened with no callback function associated, the operation will fail. |
| * |
| * Parameters: |
| * |
| * updatePeriod: position update notification period expressed in frames. |
| * |
| * Returned status (from utils/Errors.h) can be: |
| * - NO_ERROR: successful operation |
| * - INVALID_OPERATION: the AudioTrack has no callback installed. |
| */ |
| status_t setPositionUpdatePeriod(uint32_t updatePeriod); |
| status_t getPositionUpdatePeriod(uint32_t *updatePeriod); |
| |
| |
| /* Sets playback head position within AudioTrack buffer. The new position is specified |
| * in number of frames. |
| * This method must be called with the AudioTrack in paused or stopped state. |
| * Note that the actual position set is <position> modulo the AudioTrack buffer size in frames. |
| * Therefore using this method makes sense only when playing a "static" audio buffer |
| * as opposed to streaming. |
| * The getPosition() method on the other hand returns the total number of frames played since |
| * playback start. |
| * |
| * Parameters: |
| * |
| * position: New playback head position within AudioTrack buffer. |
| * |
| * Returned status (from utils/Errors.h) can be: |
| * - NO_ERROR: successful operation |
| * - INVALID_OPERATION: the AudioTrack is not stopped. |
| * - BAD_VALUE: The specified position is beyond the number of frames present in AudioTrack buffer |
| */ |
| status_t setPosition(uint32_t position); |
| status_t getPosition(uint32_t *position); |
| |
| /* Forces AudioTrack buffer full condition. When playing a static buffer, this method avoids |
| * rewriting the buffer before restarting playback after a stop. |
| * This method must be called with the AudioTrack in paused or stopped state. |
| * |
| * Returned status (from utils/Errors.h) can be: |
| * - NO_ERROR: successful operation |
| * - INVALID_OPERATION: the AudioTrack is not stopped. |
| */ |
| status_t reload(); |
| |
| /* returns a handle on the audio output used by this AudioTrack. |
| * |
| * Parameters: |
| * none. |
| * |
| * Returned value: |
| * handle on audio hardware output |
| */ |
| audio_io_handle_t getOutput(); |
| |
| /* obtains a buffer of "frameCount" frames. The buffer must be |
| * filled entirely. If the track is stopped, obtainBuffer() returns |
| * STOPPED instead of NO_ERROR as long as there are buffers availlable, |
| * at which point NO_MORE_BUFFERS is returned. |
| * Buffers will be returned until the pool (buffercount()) |
| * is exhausted, at which point obtainBuffer() will either block |
| * or return WOULD_BLOCK depending on the value of the "blocking" |
| * parameter. |
| */ |
| |
| enum { |
| NO_MORE_BUFFERS = 0x80000001, |
| STOPPED = 1 |
| }; |
| |
| status_t obtainBuffer(Buffer* audioBuffer, int32_t waitCount); |
| void releaseBuffer(Buffer* audioBuffer); |
| |
| |
| /* As a convenience we provide a write() interface to the audio buffer. |
| * This is implemented on top of lockBuffer/unlockBuffer. For best |
| * performance |
| * |
| */ |
| ssize_t write(const void* buffer, size_t size); |
| |
| /* |
| * Dumps the state of an audio track. |
| */ |
| status_t dump(int fd, const Vector<String16>& args) const; |
| |
| private: |
| /* copying audio tracks is not allowed */ |
| AudioTrack(const AudioTrack& other); |
| AudioTrack& operator = (const AudioTrack& other); |
| |
| /* a small internal class to handle the callback */ |
| class AudioTrackThread : public Thread |
| { |
| public: |
| AudioTrackThread(AudioTrack& receiver, bool bCanCallJava = false); |
| private: |
| friend class AudioTrack; |
| virtual bool threadLoop(); |
| virtual status_t readyToRun(); |
| virtual void onFirstRef(); |
| AudioTrack& mReceiver; |
| Mutex mLock; |
| }; |
| |
| bool processAudioBuffer(const sp<AudioTrackThread>& thread); |
| status_t createTrack(int streamType, |
| uint32_t sampleRate, |
| int format, |
| int channelCount, |
| int frameCount, |
| uint32_t flags, |
| const sp<IMemory>& sharedBuffer, |
| audio_io_handle_t output); |
| |
| sp<IAudioTrack> mAudioTrack; |
| sp<IMemory> mCblkMemory; |
| sp<AudioTrackThread> mAudioTrackThread; |
| |
| float mVolume[2]; |
| uint32_t mFrameCount; |
| |
| audio_track_cblk_t* mCblk; |
| uint8_t mStreamType; |
| uint8_t mFormat; |
| uint8_t mChannelCount; |
| uint8_t mMuted; |
| uint32_t mChannels; |
| status_t mStatus; |
| uint32_t mLatency; |
| |
| volatile int32_t mActive; |
| |
| callback_t mCbf; |
| void* mUserData; |
| uint32_t mNotificationFrames; |
| sp<IMemory> mSharedBuffer; |
| int mLoopCount; |
| uint32_t mRemainingFrames; |
| uint32_t mMarkerPosition; |
| bool mMarkerReached; |
| uint32_t mNewPosition; |
| uint32_t mUpdatePeriod; |
| uint32_t mFlags; |
| }; |
| |
| |
| }; // namespace android |
| |
| #endif // ANDROID_AUDIOTRACK_H |