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      1 /*
      2  * Copyright (C) 2009 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 #ifndef ANDROID_AUDIOEFFECT_H
     18 #define ANDROID_AUDIOEFFECT_H
     19 
     20 #include <stdint.h>
     21 #include <sys/types.h>
     22 
     23 #include <media/IAudioFlinger.h>
     24 #include <media/IAudioPolicyService.h>
     25 #include <media/IEffect.h>
     26 #include <media/IEffectClient.h>
     27 #include <hardware/audio_effect.h>
     28 #include <media/AudioSystem.h>
     29 
     30 #include <utils/RefBase.h>
     31 #include <utils/Errors.h>
     32 #include <binder/IInterface.h>
     33 
     34 
     35 namespace android {
     36 
     37 // ----------------------------------------------------------------------------
     38 
     39 class effect_param_cblk_t;
     40 
     41 // ----------------------------------------------------------------------------
     42 
     43 class AudioEffect : public RefBase
     44 {
     45 public:
     46 
     47     /*
     48      *  Static methods for effects enumeration.
     49      */
     50 
     51     /*
     52      * Returns the number of effects available. This method together
     53      * with queryEffect() is used to enumerate all effects:
     54      * The enumeration sequence is:
     55      *      queryNumberEffects(&num_effects);
     56      *      for (i = 0; i < num_effects; i++)
     57      *          queryEffect(i,...);
     58      *
     59      * Parameters:
     60      *      numEffects:    address where the number of effects should be returned.
     61      *
     62      * Returned status (from utils/Errors.h) can be:
     63      *      NO_ERROR   successful operation.
     64      *      PERMISSION_DENIED could not get AudioFlinger interface
     65      *      NO_INIT    effect library failed to initialize
     66      *      BAD_VALUE  invalid numEffects pointer
     67      *
     68      * Returned value
     69      *   *numEffects:     updated with number of effects available
     70      */
     71     static status_t queryNumberEffects(uint32_t *numEffects);
     72 
     73     /*
     74      * Returns an effect descriptor during effect
     75      * enumeration.
     76      *
     77      * Parameters:
     78      *      index:      index of the queried effect.
     79      *      descriptor: address where the effect descriptor should be returned.
     80      *
     81      * Returned status (from utils/Errors.h) can be:
     82      *      NO_ERROR        successful operation.
     83      *      PERMISSION_DENIED could not get AudioFlinger interface
     84      *      NO_INIT         effect library failed to initialize
     85      *      BAD_VALUE       invalid descriptor pointer or index
     86      *      INVALID_OPERATION  effect list has changed since last execution of queryNumberEffects()
     87      *
     88      * Returned value
     89      *   *descriptor:     updated with effect descriptor
     90      */
     91     static status_t queryEffect(uint32_t index, effect_descriptor_t *descriptor);
     92 
     93 
     94     /*
     95      * Returns the descriptor for the specified effect uuid.
     96      *
     97      * Parameters:
     98      *      uuid:       pointer to effect uuid.
     99      *      descriptor: address where the effect descriptor should be returned.
    100      *
    101      * Returned status (from utils/Errors.h) can be:
    102      *      NO_ERROR        successful operation.
    103      *      PERMISSION_DENIED could not get AudioFlinger interface
    104      *      NO_INIT         effect library failed to initialize
    105      *      BAD_VALUE       invalid uuid or descriptor pointers
    106      *      NAME_NOT_FOUND  no effect with this uuid found
    107      *
    108      * Returned value
    109      *   *descriptor updated with effect descriptor
    110      */
    111     static status_t getEffectDescriptor(const effect_uuid_t *uuid,
    112                                         effect_descriptor_t *descriptor) /*const*/;
    113 
    114 
    115     /*
    116      * Returns a list of descriptors corresponding to the pre processings enabled by default
    117      * on an AudioRecord with the supplied audio session ID.
    118      *
    119      * Parameters:
    120      *      audioSession:  audio session ID.
    121      *      descriptors: address where the effect descriptors should be returned.
    122      *      count: as input, the maximum number of descriptor than should be returned
    123      *             as output, the number of descriptor returned if status is NO_ERROR or the actual
    124      *             number of enabled pre processings if status is NO_MEMORY
    125      *
    126      * Returned status (from utils/Errors.h) can be:
    127      *      NO_ERROR        successful operation.
    128      *      NO_MEMORY       the number of descriptor to return is more than the maximum number
    129      *                      indicated by count.
    130      *      PERMISSION_DENIED could not get AudioFlinger interface
    131      *      NO_INIT         effect library failed to initialize
    132      *      BAD_VALUE       invalid audio session or descriptor pointers
    133      *
    134      * Returned value
    135      *   *descriptor updated with descriptors of pre processings enabled by default
    136      *   *count      number of descriptors returned if returned status is N_ERROR.
    137      *               total number of pre processing enabled by default if returned status is
    138      *               NO_MEMORY. This happens if the count passed as input is less than the number
    139      *               of descriptors to return
    140      */
    141     static status_t queryDefaultPreProcessing(int audioSession,
    142                                               effect_descriptor_t *descriptors,
    143                                               uint32_t *count);
    144 
    145     /*
    146      * Events used by callback function (effect_callback_t).
    147      */
    148     enum event_type {
    149         EVENT_CONTROL_STATUS_CHANGED = 0,
    150         EVENT_ENABLE_STATUS_CHANGED = 1,
    151         EVENT_PARAMETER_CHANGED = 2,
    152         EVENT_ERROR = 3
    153     };
    154 
    155     /* Callback function notifying client application of a change in effect engine state or
    156      * configuration.
    157      * An effect engine can be shared by several applications but only one has the control
    158      * of the engine activity and configuration at a time.
    159      * The EVENT_CONTROL_STATUS_CHANGED event is received when an application loses or
    160      * retrieves the control of the effect engine. Loss of control happens
    161      * if another application requests the use of the engine by creating an AudioEffect for
    162      * the same effect type but with a higher priority. Control is returned when the
    163      * application having the control deletes its AudioEffect object.
    164      * The EVENT_ENABLE_STATUS_CHANGED event is received by all applications not having the
    165      * control of the effect engine when the effect is enabled or disabled.
    166      * The EVENT_PARAMETER_CHANGED event is received by all applications not having the
    167      * control of the effect engine when an effect parameter is changed.
    168      * The EVENT_ERROR event is received when the media server process dies.
    169      *
    170      * Parameters:
    171      *
    172      * event:   type of event notified (see enum AudioEffect::event_type).
    173      * user:    Pointer to context for use by the callback receiver.
    174      * info:    Pointer to optional parameter according to event type:
    175      *  - EVENT_CONTROL_STATUS_CHANGED:  boolean indicating if control is granted (true)
    176      *  or stolen (false).
    177      *  - EVENT_ENABLE_STATUS_CHANGED: boolean indicating if effect is now enabled (true)
    178      *  or disabled (false).
    179      *  - EVENT_PARAMETER_CHANGED: pointer to a effect_param_t structure.
    180      *  - EVENT_ERROR:  status_t indicating the error (DEAD_OBJECT when media server dies).
    181      */
    182 
    183     typedef void (*effect_callback_t)(int32_t event, void* user, void *info);
    184 
    185 
    186     /* Constructor.
    187      * AudioEffect is the base class for creating and controlling an effect engine from
    188      * the application process. Creating an AudioEffect object will create the effect engine
    189      * in the AudioFlinger if no engine of the specified type exists. If one exists, this engine
    190      * will be used. The application creating the AudioEffect object (or a derived class like
    191      * Reverb for instance) will either receive control of the effect engine or not, depending
    192      * on the priority parameter. If priority is higher than the priority used by the current
    193      * effect engine owner, the control will be transfered to the new application. Otherwise
    194      * control will remain to the previous application. In this case, the new application will be
    195      * notified of changes in effect engine state or control ownership by the effect callback.
    196      * After creating the AudioEffect, the application must call the initCheck() method and
    197      * check the creation status before trying to control the effect engine (see initCheck()).
    198      * If the effect is to be applied to an AudioTrack or MediaPlayer only the application
    199      * must specify the audio session ID corresponding to this player.
    200      */
    201 
    202     /* Simple Constructor.
    203      */
    204     AudioEffect();
    205 
    206 
    207     /* Constructor.
    208      *
    209      * Parameters:
    210      *
    211      * type:  type of effect created: can be null if uuid is specified. This corresponds to
    212      *        the OpenSL ES interface implemented by this effect.
    213      * uuid:  Uuid of effect created: can be null if type is specified. This uuid corresponds to
    214      *        a particular implementation of an effect type.
    215      * priority:    requested priority for effect control: the priority level corresponds to the
    216      *      value of priority parameter: negative values indicate lower priorities, positive values
    217      *      higher priorities, 0 being the normal priority.
    218      * cbf:         optional callback function (see effect_callback_t)
    219      * user:        pointer to context for use by the callback receiver.
    220      * sessionID:   audio session this effect is associated to. If 0, the effect will be global to
    221      *      the output mix. If not 0, the effect will be applied to all players
    222      *      (AudioTrack or MediaPLayer) within the same audio session.
    223      * io:  HAL audio output or input stream to which this effect must be attached. Leave at 0 for
    224      *      automatic output selection by AudioFlinger.
    225      */
    226 
    227     AudioEffect(const effect_uuid_t *type,
    228                 const effect_uuid_t *uuid = NULL,
    229                   int32_t priority = 0,
    230                   effect_callback_t cbf = NULL,
    231                   void* user = NULL,
    232                   int sessionId = 0,
    233                   audio_io_handle_t io = 0
    234                   );
    235 
    236     /* Constructor.
    237      *      Same as above but with type and uuid specified by character strings
    238      */
    239     AudioEffect(const char *typeStr,
    240                     const char *uuidStr = NULL,
    241                     int32_t priority = 0,
    242                     effect_callback_t cbf = NULL,
    243                     void* user = NULL,
    244                     int sessionId = 0,
    245                     audio_io_handle_t io = 0
    246                     );
    247 
    248     /* Terminates the AudioEffect and unregisters it from AudioFlinger.
    249      * The effect engine is also destroyed if this AudioEffect was the last controlling
    250      * the engine.
    251      */
    252                         ~AudioEffect();
    253 
    254     /* Initialize an uninitialized AudioEffect.
    255     * Returned status (from utils/Errors.h) can be:
    256     *  - NO_ERROR or ALREADY_EXISTS: successful initialization
    257     *  - INVALID_OPERATION: AudioEffect is already initialized
    258     *  - BAD_VALUE: invalid parameter
    259     *  - NO_INIT: audio flinger or audio hardware not initialized
    260     * */
    261             status_t    set(const effect_uuid_t *type,
    262                             const effect_uuid_t *uuid = NULL,
    263                             int32_t priority = 0,
    264                             effect_callback_t cbf = NULL,
    265                             void* user = NULL,
    266                             int sessionId = 0,
    267                             audio_io_handle_t io = 0
    268                             );
    269 
    270     /* Result of constructing the AudioEffect. This must be checked
    271      * before using any AudioEffect API.
    272      * initCheck() can return:
    273      *  - NO_ERROR:    the effect engine is successfully created and the application has control.
    274      *  - ALREADY_EXISTS: the effect engine is successfully created but the application does not
    275      *              have control.
    276      *  - NO_INIT:     the effect creation failed.
    277      *
    278      */
    279             status_t    initCheck() const;
    280 
    281 
    282     /* Returns the unique effect Id for the controlled effect engine. This ID is unique
    283      * system wide and is used for instance in the case of auxiliary effects to attach
    284      * the effect to an AudioTrack or MediaPlayer.
    285      *
    286      */
    287             int32_t     id() const { return mId; }
    288 
    289     /* Returns a descriptor for the effect (see effect_descriptor_t in audio_effect.h).
    290      */
    291             effect_descriptor_t descriptor() const;
    292 
    293     /* Returns effect control priority of this AudioEffect object.
    294      */
    295             int32_t     priority() const { return mPriority; }
    296 
    297 
    298     /* Enables or disables the effect engine.
    299      *
    300      * Parameters:
    301      *  enabled: requested enable state.
    302      *
    303      * Returned status (from utils/Errors.h) can be:
    304      *  - NO_ERROR: successful operation
    305      *  - INVALID_OPERATION: the application does not have control of the effect engine or the
    306      *  effect is already in the requested state.
    307      */
    308     virtual status_t    setEnabled(bool enabled);
    309             bool        getEnabled() const;
    310 
    311     /* Sets a parameter value.
    312      *
    313      * Parameters:
    314      *      param:  pointer to effect_param_t structure containing the parameter
    315      *          and its value (See audio_effect.h).
    316      * Returned status (from utils/Errors.h) can be:
    317      *  - NO_ERROR: successful operation.
    318      *  - INVALID_OPERATION: the application does not have control of the effect engine.
    319      *  - BAD_VALUE: invalid parameter identifier or value.
    320      *  - DEAD_OBJECT: the effect engine has been deleted.
    321      */
    322      virtual status_t   setParameter(effect_param_t *param);
    323 
    324     /* Prepare a new parameter value that will be set by next call to
    325      * setParameterCommit(). This method can be used to set multiple parameters
    326      * in a synchronous manner or to avoid multiple binder calls for each
    327      * parameter.
    328      *
    329      * Parameters:
    330      *      param:  pointer to effect_param_t structure containing the parameter
    331      *          and its value (See audio_effect.h).
    332      *
    333      * Returned status (from utils/Errors.h) can be:
    334      *  - NO_ERROR: successful operation.
    335      *  - INVALID_OPERATION: the application does not have control of the effect engine.
    336      *  - NO_MEMORY: no more space available in shared memory used for deferred parameter
    337      *  setting.
    338      */
    339      virtual status_t   setParameterDeferred(effect_param_t *param);
    340 
    341      /* Commit all parameter values previously prepared by setParameterDeferred().
    342       *
    343       * Parameters:
    344       *     none
    345       *
    346       * Returned status (from utils/Errors.h) can be:
    347       *  - NO_ERROR: successful operation.
    348       *  - INVALID_OPERATION: No new parameter values ready for commit.
    349       *  - BAD_VALUE: invalid parameter identifier or value: there is no indication
    350       *     as to which of the parameters caused this error.
    351       *  - DEAD_OBJECT: the effect engine has been deleted.
    352       */
    353      virtual status_t   setParameterCommit();
    354 
    355     /* Gets a parameter value.
    356      *
    357      * Parameters:
    358      *      param:  pointer to effect_param_t structure containing the parameter
    359      *          and the returned value (See audio_effect.h).
    360      *
    361      * Returned status (from utils/Errors.h) can be:
    362      *  - NO_ERROR: successful operation.
    363      *  - INVALID_OPERATION: the AudioEffect was not successfully initialized.
    364      *  - BAD_VALUE: invalid parameter identifier.
    365      *  - DEAD_OBJECT: the effect engine has been deleted.
    366      */
    367      virtual status_t   getParameter(effect_param_t *param);
    368 
    369      /* Sends a command and receives a response to/from effect engine.
    370       *     See audio_effect.h for details on effect command() function, valid command codes
    371       *     and formats.
    372       */
    373      virtual status_t command(uint32_t cmdCode,
    374                               uint32_t cmdSize,
    375                               void *cmdData,
    376                               uint32_t *replySize,
    377                               void *replyData);
    378 
    379 
    380      /*
    381       * Utility functions.
    382       */
    383 
    384      /* Converts the string passed as first argument to the effect_uuid_t
    385       * pointed to by second argument
    386       */
    387      static status_t stringToGuid(const char *str, effect_uuid_t *guid);
    388      /* Converts the effect_uuid_t pointed to by first argument to the
    389       * string passed as second argument
    390       */
    391      static status_t guidToString(const effect_uuid_t *guid, char *str, size_t maxLen);
    392 
    393 protected:
    394      bool                    mEnabled;           // enable state
    395      int32_t                 mSessionId;         // audio session ID
    396      int32_t                 mPriority;          // priority for effect control
    397      status_t                mStatus;            // effect status
    398      effect_callback_t       mCbf;               // callback function for status, control and
    399                                                  // parameter changes notifications
    400      void*                   mUserData;          // client context for callback function
    401      effect_descriptor_t     mDescriptor;        // effect descriptor
    402      int32_t                 mId;                // system wide unique effect engine instance ID
    403      Mutex                   mLock;               // Mutex for mEnabled access
    404 
    405      // IEffectClient
    406      virtual void controlStatusChanged(bool controlGranted);
    407      virtual void enableStatusChanged(bool enabled);
    408      virtual void commandExecuted(uint32_t cmdCode,
    409              uint32_t cmdSize,
    410              void *pCmdData,
    411              uint32_t replySize,
    412              void *pReplyData);
    413 
    414 private:
    415 
    416      // Implements the IEffectClient interface
    417     class EffectClient : public android::BnEffectClient,  public android::IBinder::DeathRecipient
    418     {
    419     public:
    420 
    421         EffectClient(AudioEffect *effect) : mEffect(effect){}
    422 
    423         // IEffectClient
    424         virtual void controlStatusChanged(bool controlGranted) {
    425             mEffect->controlStatusChanged(controlGranted);
    426         }
    427         virtual void enableStatusChanged(bool enabled) {
    428             mEffect->enableStatusChanged(enabled);
    429         }
    430         virtual void commandExecuted(uint32_t cmdCode,
    431                                      uint32_t cmdSize,
    432                                      void *pCmdData,
    433                                      uint32_t replySize,
    434                                      void *pReplyData) {
    435             mEffect->commandExecuted(cmdCode, cmdSize, pCmdData, replySize, pReplyData);
    436         }
    437 
    438         // IBinder::DeathRecipient
    439         virtual void binderDied(const wp<IBinder>& who) {mEffect->binderDied();}
    440 
    441     private:
    442         AudioEffect *mEffect;
    443     };
    444 
    445     void binderDied();
    446 
    447     sp<IEffect>             mIEffect;           // IEffect binder interface
    448     sp<EffectClient>        mIEffectClient;     // IEffectClient implementation
    449     sp<IMemory>             mCblkMemory;        // shared memory for deferred parameter setting
    450     effect_param_cblk_t*    mCblk;              // control block for deferred parameter setting
    451 };
    452 
    453 
    454 }; // namespace android
    455 
    456 #endif // ANDROID_AUDIOEFFECT_H
    457