Home | History | Annotate | Download | only in media
      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 struct 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.
    221      *      If equal to AUDIO_SESSION_OUTPUT_MIX, the effect will be global to
    222      *      the output mix.  Otherwise, the effect will be applied to all players
    223      *      (AudioTrack or MediaPLayer) within the same audio session.
    224      * io:  HAL audio output or input stream to which this effect must be attached. Leave at 0 for
    225      *      automatic output selection by AudioFlinger.
    226      */
    227 
    228     AudioEffect(const effect_uuid_t *type,
    229                 const effect_uuid_t *uuid = NULL,
    230                   int32_t priority = 0,
    231                   effect_callback_t cbf = NULL,
    232                   void* user = NULL,
    233                   int sessionId = AUDIO_SESSION_OUTPUT_MIX,
    234                   audio_io_handle_t io = AUDIO_IO_HANDLE_NONE
    235                   );
    236 
    237     /* Constructor.
    238      *      Same as above but with type and uuid specified by character strings
    239      */
    240     AudioEffect(const char *typeStr,
    241                     const char *uuidStr = NULL,
    242                     int32_t priority = 0,
    243                     effect_callback_t cbf = NULL,
    244                     void* user = NULL,
    245                     int sessionId = AUDIO_SESSION_OUTPUT_MIX,
    246                     audio_io_handle_t io = AUDIO_IO_HANDLE_NONE
    247                     );
    248 
    249     /* Terminates the AudioEffect and unregisters it from AudioFlinger.
    250      * The effect engine is also destroyed if this AudioEffect was the last controlling
    251      * the engine.
    252      */
    253                         ~AudioEffect();
    254 
    255     /* Initialize an uninitialized AudioEffect.
    256     * Returned status (from utils/Errors.h) can be:
    257     *  - NO_ERROR or ALREADY_EXISTS: successful initialization
    258     *  - INVALID_OPERATION: AudioEffect is already initialized
    259     *  - BAD_VALUE: invalid parameter
    260     *  - NO_INIT: audio flinger or audio hardware not initialized
    261     * */
    262             status_t    set(const effect_uuid_t *type,
    263                             const effect_uuid_t *uuid = NULL,
    264                             int32_t priority = 0,
    265                             effect_callback_t cbf = NULL,
    266                             void* user = NULL,
    267                             int sessionId = AUDIO_SESSION_OUTPUT_MIX,
    268                             audio_io_handle_t io = AUDIO_IO_HANDLE_NONE
    269                             );
    270 
    271     /* Result of constructing the AudioEffect. This must be checked
    272      * before using any AudioEffect API.
    273      * initCheck() can return:
    274      *  - NO_ERROR:    the effect engine is successfully created and the application has control.
    275      *  - ALREADY_EXISTS: the effect engine is successfully created but the application does not
    276      *              have control.
    277      *  - NO_INIT:     the effect creation failed.
    278      *
    279      */
    280             status_t    initCheck() const;
    281 
    282 
    283     /* Returns the unique effect Id for the controlled effect engine. This ID is unique
    284      * system wide and is used for instance in the case of auxiliary effects to attach
    285      * the effect to an AudioTrack or MediaPlayer.
    286      *
    287      */
    288             int32_t     id() const { return mId; }
    289 
    290     /* Returns a descriptor for the effect (see effect_descriptor_t in audio_effect.h).
    291      */
    292             effect_descriptor_t descriptor() const;
    293 
    294     /* Returns effect control priority of this AudioEffect object.
    295      */
    296             int32_t     priority() const { return mPriority; }
    297 
    298 
    299     /* Enables or disables the effect engine.
    300      *
    301      * Parameters:
    302      *  enabled: requested enable state.
    303      *
    304      * Returned status (from utils/Errors.h) can be:
    305      *  - NO_ERROR: successful operation
    306      *  - INVALID_OPERATION: the application does not have control of the effect engine or the
    307      *  effect is already in the requested state.
    308      */
    309     virtual status_t    setEnabled(bool enabled);
    310             bool        getEnabled() const;
    311 
    312     /* Sets a parameter value.
    313      *
    314      * Parameters:
    315      *      param:  pointer to effect_param_t structure containing the parameter
    316      *          and its value (See audio_effect.h).
    317      * Returned status (from utils/Errors.h) can be:
    318      *  - NO_ERROR: successful operation.
    319      *  - INVALID_OPERATION: the application does not have control of the effect engine.
    320      *  - BAD_VALUE: invalid parameter identifier or value.
    321      *  - DEAD_OBJECT: the effect engine has been deleted.
    322      */
    323      virtual status_t   setParameter(effect_param_t *param);
    324 
    325     /* Prepare a new parameter value that will be set by next call to
    326      * setParameterCommit(). This method can be used to set multiple parameters
    327      * in a synchronous manner or to avoid multiple binder calls for each
    328      * parameter.
    329      *
    330      * Parameters:
    331      *      param:  pointer to effect_param_t structure containing the parameter
    332      *          and its value (See audio_effect.h).
    333      *
    334      * Returned status (from utils/Errors.h) can be:
    335      *  - NO_ERROR: successful operation.
    336      *  - INVALID_OPERATION: the application does not have control of the effect engine.
    337      *  - NO_MEMORY: no more space available in shared memory used for deferred parameter
    338      *  setting.
    339      */
    340      virtual status_t   setParameterDeferred(effect_param_t *param);
    341 
    342      /* Commit all parameter values previously prepared by setParameterDeferred().
    343       *
    344       * Parameters:
    345       *     none
    346       *
    347       * Returned status (from utils/Errors.h) can be:
    348       *  - NO_ERROR: successful operation.
    349       *  - INVALID_OPERATION: No new parameter values ready for commit.
    350       *  - BAD_VALUE: invalid parameter identifier or value: there is no indication
    351       *     as to which of the parameters caused this error.
    352       *  - DEAD_OBJECT: the effect engine has been deleted.
    353       */
    354      virtual status_t   setParameterCommit();
    355 
    356     /* Gets a parameter value.
    357      *
    358      * Parameters:
    359      *      param:  pointer to effect_param_t structure containing the parameter
    360      *          and the returned value (See audio_effect.h).
    361      *
    362      * Returned status (from utils/Errors.h) can be:
    363      *  - NO_ERROR: successful operation.
    364      *  - INVALID_OPERATION: the AudioEffect was not successfully initialized.
    365      *  - BAD_VALUE: invalid parameter identifier.
    366      *  - DEAD_OBJECT: the effect engine has been deleted.
    367      */
    368      virtual status_t   getParameter(effect_param_t *param);
    369 
    370      /* Sends a command and receives a response to/from effect engine.
    371       *     See audio_effect.h for details on effect command() function, valid command codes
    372       *     and formats.
    373       */
    374      virtual status_t command(uint32_t cmdCode,
    375                               uint32_t cmdSize,
    376                               void *cmdData,
    377                               uint32_t *replySize,
    378                               void *replyData);
    379 
    380 
    381      /*
    382       * Utility functions.
    383       */
    384 
    385      /* Converts the string passed as first argument to the effect_uuid_t
    386       * pointed to by second argument
    387       */
    388      static status_t stringToGuid(const char *str, effect_uuid_t *guid);
    389      /* Converts the effect_uuid_t pointed to by first argument to the
    390       * string passed as second argument
    391       */
    392      static status_t guidToString(const effect_uuid_t *guid, char *str, size_t maxLen);
    393 
    394 protected:
    395      bool                    mEnabled;           // enable state
    396      int32_t                 mSessionId;         // audio session ID
    397      int32_t                 mPriority;          // priority for effect control
    398      status_t                mStatus;            // effect status
    399      effect_callback_t       mCbf;               // callback function for status, control and
    400                                                  // parameter changes notifications
    401      void*                   mUserData;          // client context for callback function
    402      effect_descriptor_t     mDescriptor;        // effect descriptor
    403      int32_t                 mId;                // system wide unique effect engine instance ID
    404      Mutex                   mLock;               // Mutex for mEnabled access
    405 
    406      // IEffectClient
    407      virtual void controlStatusChanged(bool controlGranted);
    408      virtual void enableStatusChanged(bool enabled);
    409      virtual void commandExecuted(uint32_t cmdCode,
    410              uint32_t cmdSize,
    411              void *pCmdData,
    412              uint32_t replySize,
    413              void *pReplyData);
    414 
    415 private:
    416 
    417      // Implements the IEffectClient interface
    418     class EffectClient : public android::BnEffectClient,  public android::IBinder::DeathRecipient
    419     {
    420     public:
    421 
    422         EffectClient(AudioEffect *effect) : mEffect(effect){}
    423 
    424         // IEffectClient
    425         virtual void controlStatusChanged(bool controlGranted) {
    426             mEffect->controlStatusChanged(controlGranted);
    427         }
    428         virtual void enableStatusChanged(bool enabled) {
    429             mEffect->enableStatusChanged(enabled);
    430         }
    431         virtual void commandExecuted(uint32_t cmdCode,
    432                                      uint32_t cmdSize,
    433                                      void *pCmdData,
    434                                      uint32_t replySize,
    435                                      void *pReplyData) {
    436             mEffect->commandExecuted(cmdCode, cmdSize, pCmdData, replySize, pReplyData);
    437         }
    438 
    439         // IBinder::DeathRecipient
    440         virtual void binderDied(const wp<IBinder>& who) {mEffect->binderDied();}
    441 
    442     private:
    443         AudioEffect *mEffect;
    444     };
    445 
    446     void binderDied();
    447 
    448     sp<IEffect>             mIEffect;           // IEffect binder interface
    449     sp<EffectClient>        mIEffectClient;     // IEffectClient implementation
    450     sp<IMemory>             mCblkMemory;        // shared memory for deferred parameter setting
    451     effect_param_cblk_t*    mCblk;              // control block for deferred parameter setting
    452     pid_t                   mClientPid;
    453 };
    454 
    455 
    456 }; // namespace android
    457 
    458 #endif // ANDROID_AUDIOEFFECT_H
    459