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/IEffect.h>
     25 #include <media/IEffectClient.h>
     26 #include <media/EffectApi.h>
     27 #include <media/AudioSystem.h>
     28 
     29 #include <utils/RefBase.h>
     30 #include <utils/Errors.h>
     31 #include <binder/IInterface.h>
     32 
     33 
     34 namespace android {
     35 
     36 // ----------------------------------------------------------------------------
     37 
     38 class effect_param_cblk_t;
     39 
     40 // ----------------------------------------------------------------------------
     41 
     42 class AudioEffect : public RefBase
     43 {
     44 public:
     45 
     46     /*
     47      *  Static methods for effect libraries management.
     48      */
     49 
     50     /*
     51      *   Loads the effect library which path is given as first argument.
     52      *   This must be the full path of a dynamic library (.so) implementing one or
     53      *   more effect engines and exposing the effect library interface described in
     54      *   EffectApi.h. The function returns a handle on the library for use by
     55      *   further call to unloadEffectLibrary() to unload the library.
     56      *
     57      *   Parameters:
     58      *          libPath:    full path of the dynamic library file in the file system.
     59      *          handle:     address where to return the library handle
     60      *
     61      *   Returned status (from utils/Errors.h) can be:
     62      *          NO_ERROR    successful operation.
     63      *          PERMISSION_DENIED could not get AudioFlinger interface or
     64      *                      application does not have permission to configure audio
     65      *          NO_INIT     effect factory not initialized or
     66      *                      library could not be loaded or
     67      *                      library does not implement required functions
     68      *          BAD_VALUE   invalid libPath string or handle
     69      *
     70      *   Returned value:
     71      *          *handle updated with library handle
     72      */
     73     static status_t loadEffectLibrary(const char *libPath, int *handle);
     74 
     75     /*
     76      *   Unloads the effect library which handle is given as argument.
     77      *
     78      *   Parameters:
     79      *          handle: library handle
     80      *
     81      *   Returned status (from utils/Errors.h) can be:
     82      *          NO_ERROR    successful operation.
     83      *          PERMISSION_DENIED could not get AudioFlinger interface or
     84      *                      application does not have permission to configure audio
     85      *          NO_INIT     effect factory not initialized
     86      *          BAD_VALUE   invalid handle
     87      */
     88     static status_t unloadEffectLibrary(int handle);
     89 
     90     /*
     91      *  Static methods for effects enumeration.
     92      */
     93 
     94     /*
     95      * Returns the number of effects available. This method together
     96      * with queryEffect() is used to enumerate all effects:
     97      * The enumeration sequence is:
     98      *      queryNumberEffects(&num_effects);
     99      *      for (i = 0; i < num_effects; i++)
    100      *          queryEffect(i,...);
    101      *
    102      * Parameters:
    103      *      numEffects:    address where the number of effects should be returned.
    104      *
    105      * Returned status (from utils/Errors.h) can be:
    106      *      NO_ERROR   successful operation.
    107      *      PERMISSION_DENIED could not get AudioFlinger interface
    108      *      NO_INIT    effect library failed to initialize
    109      *      BAD_VALUE  invalid numEffects pointer
    110      *
    111      * Returned value
    112      *   *numEffects:     updated with number of effects available
    113      */
    114     static status_t queryNumberEffects(uint32_t *numEffects);
    115 
    116     /*
    117      * Returns an effect descriptor during effect
    118      * enumeration.
    119      *
    120      * Parameters:
    121      *      index:      index of the queried effect.
    122      *      descriptor: address where the effect descriptor should be returned.
    123      *
    124      * Returned status (from utils/Errors.h) can be:
    125      *      NO_ERROR        successful operation.
    126      *      PERMISSION_DENIED could not get AudioFlinger interface
    127      *      NO_INIT         effect library failed to initialize
    128      *      BAD_VALUE       invalid descriptor pointer or index
    129      *      INVALID_OPERATION  effect list has changed since last execution of queryNumberEffects()
    130      *
    131      * Returned value
    132      *   *descriptor:     updated with effect descriptor
    133      */
    134     static status_t queryEffect(uint32_t index, effect_descriptor_t *descriptor);
    135 
    136 
    137     /*
    138      * Returns the descriptor for the specified effect uuid.
    139      *
    140      * Parameters:
    141      *      uuid:       pointer to effect uuid.
    142      *      descriptor: address where the effect descriptor should be returned.
    143      *
    144      * Returned status (from utils/Errors.h) can be:
    145      *      NO_ERROR        successful operation.
    146      *      PERMISSION_DENIED could not get AudioFlinger interface
    147      *      NO_INIT         effect library failed to initialize
    148      *      BAD_VALUE       invalid uuid or descriptor pointers
    149      *      NAME_NOT_FOUND  no effect with this uuid found
    150      *
    151      * Returned value
    152      *   *descriptor updated with effect descriptor
    153      */
    154     static status_t getEffectDescriptor(effect_uuid_t *uuid, effect_descriptor_t *descriptor);
    155 
    156 
    157     /*
    158      * Events used by callback function (effect_callback_t).
    159      */
    160     enum event_type {
    161         EVENT_CONTROL_STATUS_CHANGED = 0,
    162         EVENT_ENABLE_STATUS_CHANGED = 1,
    163         EVENT_PARAMETER_CHANGED = 2,
    164         EVENT_ERROR = 3
    165     };
    166 
    167     /* Callback function notifying client application of a change in effect engine state or
    168      * configuration.
    169      * An effect engine can be shared by several applications but only one has the control
    170      * of the engine activity and configuration at a time.
    171      * The EVENT_CONTROL_STATUS_CHANGED event is received when an application loses or
    172      * retrieves the control of the effect engine. Loss of control happens
    173      * if another application requests the use of the engine by creating an AudioEffect for
    174      * the same effect type but with a higher priority. Control is returned when the
    175      * application having the control deletes its AudioEffect object.
    176      * The EVENT_ENABLE_STATUS_CHANGED event is received by all applications not having the
    177      * control of the effect engine when the effect is enabled or disabled.
    178      * The EVENT_PARAMETER_CHANGED event is received by all applications not having the
    179      * control of the effect engine when an effect parameter is changed.
    180      * The EVENT_ERROR event is received when the media server process dies.
    181      *
    182      * Parameters:
    183      *
    184      * event:   type of event notified (see enum AudioEffect::event_type).
    185      * user:    Pointer to context for use by the callback receiver.
    186      * info:    Pointer to optional parameter according to event type:
    187      *  - EVENT_CONTROL_STATUS_CHANGED:  boolean indicating if control is granted (true)
    188      *  or stolen (false).
    189      *  - EVENT_ENABLE_STATUS_CHANGED: boolean indicating if effect is now enabled (true)
    190      *  or disabled (false).
    191      *  - EVENT_PARAMETER_CHANGED: pointer to a effect_param_t structure.
    192      *  - EVENT_ERROR:  status_t indicating the error (DEAD_OBJECT when media server dies).
    193      */
    194 
    195     typedef void (*effect_callback_t)(int32_t event, void* user, void *info);
    196 
    197 
    198     /* Constructor.
    199      * AudioEffect is the base class for creating and controlling an effect engine from
    200      * the application process. Creating an AudioEffect object will create the effect engine
    201      * in the AudioFlinger if no engine of the specified type exists. If one exists, this engine
    202      * will be used. The application creating the AudioEffect object (or a derived class like
    203      * Reverb for instance) will either receive control of the effect engine or not, depending
    204      * on the priority parameter. If priority is higher than the priority used by the current
    205      * effect engine owner, the control will be transfered to the new application. Otherwise
    206      * control will remain to the previous application. In this case, the new application will be
    207      * notified of changes in effect engine state or control ownership by the effect callback.
    208      * After creating the AudioEffect, the application must call the initCheck() method and
    209      * check the creation status before trying to control the effect engine (see initCheck()).
    210      * If the effect is to be applied to an AudioTrack or MediaPlayer only the application
    211      * must specify the audio session ID corresponding to this player.
    212      */
    213 
    214     /* Simple Constructor.
    215      */
    216     AudioEffect();
    217 
    218 
    219     /* Constructor.
    220      *
    221      * Parameters:
    222      *
    223      * type:  type of effect created: can be null if uuid is specified. This corresponds to
    224      *        the OpenSL ES interface implemented by this effect.
    225      * uuid:  Uuid of effect created: can be null if type is specified. This uuid corresponds to
    226      *        a particular implementation of an effect type.
    227      * priority:    requested priority for effect control: the priority level corresponds to the
    228      *      value of priority parameter: negative values indicate lower priorities, positive values
    229      *      higher priorities, 0 being the normal priority.
    230      * cbf:         optional callback function (see effect_callback_t)
    231      * user:        pointer to context for use by the callback receiver.
    232      * sessionID:   audio session this effect is associated to. If 0, the effect will be global to
    233      *      the output mix. If not 0, the effect will be applied to all players
    234      *      (AudioTrack or MediaPLayer) within the same audio session.
    235      * output:  HAL audio output stream to which this effect must be attached. Leave at 0 for
    236      *      automatic output selection by AudioFlinger.
    237      */
    238 
    239     AudioEffect(const effect_uuid_t *type,
    240                 const effect_uuid_t *uuid = NULL,
    241                   int32_t priority = 0,
    242                   effect_callback_t cbf = 0,
    243                   void* user = 0,
    244                   int sessionId = 0,
    245                   audio_io_handle_t output = 0
    246                   );
    247 
    248     /* Constructor.
    249      *      Same as above but with type and uuid specified by character strings
    250      */
    251     AudioEffect(const char *typeStr,
    252                     const char *uuidStr = NULL,
    253                     int32_t priority = 0,
    254                     effect_callback_t cbf = 0,
    255                     void* user = 0,
    256                     int sessionId = 0,
    257                     audio_io_handle_t output = 0
    258                     );
    259 
    260     /* Terminates the AudioEffect and unregisters it from AudioFlinger.
    261      * The effect engine is also destroyed if this AudioEffect was the last controlling
    262      * the engine.
    263      */
    264                         ~AudioEffect();
    265 
    266     /* Initialize an uninitialized AudioEffect.
    267     * Returned status (from utils/Errors.h) can be:
    268     *  - NO_ERROR or ALREADY_EXISTS: successful initialization
    269     *  - INVALID_OPERATION: AudioEffect is already initialized
    270     *  - BAD_VALUE: invalid parameter
    271     *  - NO_INIT: audio flinger or audio hardware not initialized
    272     * */
    273             status_t    set(const effect_uuid_t *type,
    274                             const effect_uuid_t *uuid = NULL,
    275                             int32_t priority = 0,
    276                             effect_callback_t cbf = 0,
    277                             void* user = 0,
    278                             int sessionId = 0,
    279                             audio_io_handle_t output = 0
    280                             );
    281 
    282     /* Result of constructing the AudioEffect. This must be checked
    283      * before using any AudioEffect API.
    284      * initCheck() can return:
    285      *  - NO_ERROR:    the effect engine is successfully created and the application has control.
    286      *  - ALREADY_EXISTS: the effect engine is successfully created but the application does not
    287      *              have control.
    288      *  - NO_INIT:     the effect creation failed.
    289      *
    290      */
    291             status_t    initCheck() const;
    292 
    293 
    294     /* Returns the unique effect Id for the controlled effect engine. This ID is unique
    295      * system wide and is used for instance in the case of auxiliary effects to attach
    296      * the effect to an AudioTrack or MediaPlayer.
    297      *
    298      */
    299             int32_t     id() const { return mId; }
    300 
    301     /* Returns a descriptor for the effect (see effect_descriptor_t in EffectApi.h).
    302      */
    303             effect_descriptor_t descriptor() const;
    304 
    305     /* Returns effect control priority of this AudioEffect object.
    306      */
    307             int32_t     priority() const { return mPriority; }
    308 
    309 
    310     /* Enables or disables the effect engine.
    311      *
    312      * Parameters:
    313      *  enabled: requested enable state.
    314      *
    315      * Returned status (from utils/Errors.h) can be:
    316      *  - NO_ERROR: successful operation
    317      *  - INVALID_OPERATION: the application does not have control of the effect engine or the
    318      *  effect is already in the requested state.
    319      */
    320     virtual status_t    setEnabled(bool enabled);
    321             bool        getEnabled() const;
    322 
    323     /* Sets a parameter value.
    324      *
    325      * Parameters:
    326      *      param:  pointer to effect_param_t structure containing the parameter
    327      *          and its value (See EffectApi.h).
    328      * Returned status (from utils/Errors.h) can be:
    329      *  - NO_ERROR: successful operation.
    330      *  - INVALID_OPERATION: the application does not have control of the effect engine.
    331      *  - BAD_VALUE: invalid parameter identifier or value.
    332      *  - DEAD_OBJECT: the effect engine has been deleted.
    333      */
    334      virtual status_t   setParameter(effect_param_t *param);
    335 
    336     /* Prepare a new parameter value that will be set by next call to
    337      * setParameterCommit(). This method can be used to set multiple parameters
    338      * in a synchronous manner or to avoid multiple binder calls for each
    339      * parameter.
    340      *
    341      * Parameters:
    342      *      param:  pointer to effect_param_t structure containing the parameter
    343      *          and its value (See EffectApi.h).
    344      *
    345      * Returned status (from utils/Errors.h) can be:
    346      *  - NO_ERROR: successful operation.
    347      *  - INVALID_OPERATION: the application does not have control of the effect engine.
    348      *  - NO_MEMORY: no more space available in shared memory used for deferred parameter
    349      *  setting.
    350      */
    351      virtual status_t   setParameterDeferred(effect_param_t *param);
    352 
    353      /* Commit all parameter values previously prepared by setParameterDeferred().
    354       *
    355       * Parameters:
    356       *     none
    357       *
    358       * Returned status (from utils/Errors.h) can be:
    359       *  - NO_ERROR: successful operation.
    360       *  - INVALID_OPERATION: No new parameter values ready for commit.
    361       *  - BAD_VALUE: invalid parameter identifier or value: there is no indication
    362       *     as to which of the parameters caused this error.
    363       *  - DEAD_OBJECT: the effect engine has been deleted.
    364       */
    365      virtual status_t   setParameterCommit();
    366 
    367     /* Gets a parameter value.
    368      *
    369      * Parameters:
    370      *      param:  pointer to effect_param_t structure containing the parameter
    371      *          and the returned value (See EffectApi.h).
    372      *
    373      * Returned status (from utils/Errors.h) can be:
    374      *  - NO_ERROR: successful operation.
    375      *  - INVALID_OPERATION: the AudioEffect was not successfully initialized.
    376      *  - BAD_VALUE: invalid parameter identifier.
    377      *  - DEAD_OBJECT: the effect engine has been deleted.
    378      */
    379      virtual status_t   getParameter(effect_param_t *param);
    380 
    381      /* Sends a command and receives a response to/from effect engine.
    382       *     See EffectApi.h for details on effect command() function, valid command codes
    383       *     and formats.
    384       */
    385      virtual status_t command(uint32_t cmdCode,
    386                               uint32_t cmdSize,
    387                               void *cmdData,
    388                               uint32_t *replySize,
    389                               void *replyData);
    390 
    391 
    392      /*
    393       * Utility functions.
    394       */
    395 
    396      /* Converts the string passed as first argument to the effect_uuid_t
    397       * pointed to by second argument
    398       */
    399      static status_t stringToGuid(const char *str, effect_uuid_t *guid);
    400      /* Converts the effect_uuid_t pointed to by first argument to the
    401       * string passed as second argument
    402       */
    403      static status_t guidToString(const effect_uuid_t *guid, char *str, size_t maxLen);
    404 
    405 protected:
    406      volatile int32_t        mEnabled;           // enable state
    407      int32_t                 mSessionId;         // audio session ID
    408      int32_t                 mPriority;          // priority for effect control
    409      status_t                mStatus;            // effect status
    410      effect_callback_t       mCbf;               // callback function for status, control and
    411                                                  // parameter changes notifications
    412      void*                   mUserData;          // client context for callback function
    413      effect_descriptor_t     mDescriptor;        // effect descriptor
    414      int32_t                 mId;                // system wide unique effect engine instance ID
    415 
    416 private:
    417 
    418      // Implements the IEffectClient interface
    419     class EffectClient : public android::BnEffectClient,  public android::IBinder::DeathRecipient
    420     {
    421     public:
    422 
    423         EffectClient(AudioEffect *effect) : mEffect(effect){}
    424 
    425         // IEffectClient
    426         virtual void controlStatusChanged(bool controlGranted) {
    427             mEffect->controlStatusChanged(controlGranted);
    428         }
    429         virtual void enableStatusChanged(bool enabled) {
    430             mEffect->enableStatusChanged(enabled);
    431         }
    432         virtual void commandExecuted(uint32_t cmdCode,
    433                                      uint32_t cmdSize,
    434                                      void *pCmdData,
    435                                      uint32_t replySize,
    436                                      void *pReplyData) {
    437             mEffect->commandExecuted(cmdCode, cmdSize, pCmdData, replySize, pReplyData);
    438         }
    439 
    440         // IBinder::DeathRecipient
    441         virtual void binderDied(const wp<IBinder>& who) {mEffect->binderDied();}
    442 
    443     private:
    444         AudioEffect *mEffect;
    445     };
    446 
    447 
    448     friend class EffectClient;
    449 
    450     // IEffectClient
    451     void controlStatusChanged(bool controlGranted);
    452     void enableStatusChanged(bool enabled);
    453     void commandExecuted(uint32_t cmdCode,
    454                          uint32_t cmdSize,
    455                          void *pCmdData,
    456                          uint32_t replySize,
    457                          void *pReplyData);
    458     void binderDied();
    459 
    460 
    461     sp<IEffect>             mIEffect;           // IEffect binder interface
    462     sp<EffectClient>        mIEffectClient;     // IEffectClient implementation
    463     sp<IMemory>             mCblkMemory;        // shared memory for deferred parameter setting
    464     effect_param_cblk_t*    mCblk;              // control block for deferred parameter setting
    465 };
    466 
    467 
    468 }; // namespace android
    469 
    470 #endif // ANDROID_AUDIOEFFECT_H
    471