1 /*

     2 * Copyright (c) 2005 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:  Group for equalizer controls

    15 *

    16 */

    17 

    18 

    19 #ifndef CAMMSEQUALIZERCONTROLGROUP_H

    20 #define CAMMSEQUALIZERCONTROLGROUP_H

    21 

    22 //  INCLUDES

    23 #include <e32base.h>

    24 #include "cammseffectcontrolgroup.h"

    25 #include <AudioEqualizerData.h>

    26 

    27 // CONSTANTS

    28 _LIT(KAMMSEqualizerControlClassName,

    29      ".amms.control.audioeffect.EqualizerControl");

    30 

    31 

    32 // FORWARD DECLARATIONS

    33 class CAMMSBaseEqualizerControl;

    34 class CAudioEqualizerUtility;

    35 

    36 

    37 // CLASS DECLARATION

    38 /**

    39  *  Group for equalizer controls

    40  *

    41  *  @since 3.0

    42  */

    43 NONSHARABLE_CLASS(CAMMSEqualizerControlGroup): public CAMMSEffectControlGroup

    44 {

    45 public:  // Constructors and destructor

    46 

    47     /**

    48      * Two-phased constructor.

    49      */

    50     static CAMMSEqualizerControlGroup* NewLC();

    51 

    52     /**

    53      * Destructor.

    54      */

    55     ~CAMMSEqualizerControlGroup();

    56 

    57 public: // New functions

    58     /**

    59      * Gets the band that has the most effect on the given frequency

    60      *

    61      * @param aFrequency    The frequency in milliHertz which is

    62      *                      to be equalized via the returned band

    63      *

    64      * @return The frequency band that has most effect on the given

    65      * frequency or -1 if no band has effect on the given frequency

    66      */

    67     TInt Band(TInt aFrequency);

    68 

    69     /**

    70      * Gets the gain set for the given equalizer band.

    71      *

    72      * @param aBand         The frequency band whose gain is asked.

    73      * @param aBandLevel    The returned level for the given band in millibels.

    74      *

    75      */

    76     void GetBandLevelL(TInt aBand, TInt& aBandLevel);

    77 

    78     /**

    79      * Gets the bass level.

    80      *

    81      * @return The current level that is set to the bass band. If the

    82      * bass level cannot been defined EqualizerControl.UNDEFINED will

    83      * be returned

    84      */

    85     TInt Bass();

    86 

    87     /**

    88      * Gets the center frequency of the given band

    89      *

    90      * @param aBand         The frequency band whose center frequency

    91      *                      is asked.

    92      * @param aCenterFreq   The returned center frequency in milliHertz.

    93      */

    94     void GetCenterFreqL(TInt aBand, TInt& aCenterFreq);

    95 

    96     /**

    97      * Returns the maximum band level supported

    98      *

    99      * @return the maximum band level supported

   100      */

   101     TInt MaxBandLevel();

   102 

   103     /**

   104      * Returns the minimum band level supported.

   105      *

   106      * @return the minimum band level supported.

   107      */

   108     TInt MinBandLevel();

   109 

   110     /**

   111      * Gets the number of frequency bands that the equalizer supports.

   112      *

   113      * @return the number of frequency bands that the equalizer supports.

   114      */

   115     TInt NumberOfBands();

   116 

   117     /**

   118      * Gets the treble level.

   119      *

   120      * @return The current level that is set to the treble band. If the

   121      * treble level cannot been defined EqualizerControl.UNDEFINED will

   122      * be returned

   123      */

   124     TInt Treble();

   125 

   126     /**

   127      * Sets the given equalizer band to the given gain value.

   128      *

   129      * @param aLevel    The new gain in millibels that will be set to the

   130      *                  given band

   131      * @param aBand     The frequency band that will have the new gain

   132      */

   133     void SetBandLevelL(TInt aLevel, TInt aBand);

   134 

   135     /**

   136      * Sets the bass level using a linear point scale with values between

   137      * 0 and 100: a value of 0 applies the maximum available attenuation

   138      * to frequencies in the bass band; a value of 50 gives a flat

   139      * equalization of the bass band; and a value of 100 applies the

   140      * maximum available amplification to frequencies in the bass band.

   141      *

   142      * @param aLevel    The new level on a linear point scale that will

   143      *                  be set to the bass band

   144      * @param aSetLevel Returned level that was actually set

   145      */

   146     void SetBassL(TInt aLevel, TInt& aSetLevel);

   147 

   148     /**

   149      * Sets the treble level using a linear point scale with values between

   150      * 0 and 100: a value of 0 applies the maximum available attenuation to

   151      * frequencies in the treble band; a value of 50 gives a flat

   152      * equalization of the treble band; and a value of 100 applies the

   153      * maximum available amplification to frequencies in the treble band

   154      *

   155      * @param aLevel    The new level on a linear point scale that will

   156      *                  be set to the treble band

   157      *

   158      * @param aSetLevel Returned level that was actually set

   159      */

   160     void SetTrebleL(TInt aLevel, TInt& aSetLevel);

   161 

   162 private: // New functions

   163     /**

   164      * Gets control. Ownership is not tranferred.

   165      *

   166      * @param aIndex Control index.

   167      */

   168     CAMMSBaseEqualizerControl* TypeSafeControl(TInt aIndex) const;

   169 

   170     /**

   171      * Checks whether the band index is between 0 and number of bands -1.

   172      * Function leaves with KErrArgument if the band is not between the

   173      * limits.

   174      */

   175     void CheckBandIndexL(TInt aBand) const;

   176 

   177     /**

   178      * Gets bands corresponding to the given preset index.

   179      * The data is obtained from controls (or from empty group utility, if the

   180      * group has no controls).

   181      * @param aPresetIndex Index of the preset whose bands are asked

   182      * @param aBands Returned bands

   183      */

   184     void GetPresetBandsL(TUint aPresetIndex,

   185                          RArray< TEfAudioEqualizerBand >& aBands);

   186 

   187 public: // Functions from base classes

   188     /**

   189      * Returns class name that identifies this control group.

   190      *

   191      * @return Control group name.

   192      */

   193     const TDesC16& ClassName();

   194 

   195 protected: // Functions from base classes

   196     /**

   197      * Called by when a new player is added

   198      *

   199      * @param aPlayer   The player being added

   200      * @param aControl  The player's control relevant to this group

   201      */

   202     void NotifyPlayerAddedL(CMMAPlayer *aPlayer, CMMAControl* aControl);

   203 

   204     /**

   205      * Called when the current preset changes

   206      */

   207     void PresetChangedL();

   208 

   209     /**

   210      * Finish initialization (after the 1st player is added)

   211      */

   212     void InitializeL();

   213 

   214     /**

   215      * Creates utilities that can be used to obtain preset names

   216      * and preset data (needed when the group has no controls).

   217      * Does nothing if the utility already exists.

   218      */

   219     void PrepareEmptyGroupUtilitiesL();

   220 

   221     /**

   222      * Deletes utilities that are used to obtain preset names

   223      * and preset data (needed when the group has no controls).

   224      * Does nothing if the utilities have already been deleted.

   225      */

   226     void DeleteEmptyGroupUtilities();

   227 

   228     /**

   229      * Gets list of preset names available.

   230      * @param aPresetNames Returned preset names

   231      */

   232     void GetPresetNamesL(CDesCArray& aPresetNames);

   233 

   234 protected:

   235     /**

   236      * C++ default constructor.

   237      */

   238     CAMMSEqualizerControlGroup();

   239 

   240     /**

   241      * By default Symbian 2nd phase constructor is private.

   242      */

   243     void ConstructL();

   244 

   245 private: // data

   246 

   247     // Needed to get preset names when the group has no controls.

   248     CAudioEqualizerUtility* iEmptyAudioEqualizerUtility;  // Owned.

   249 

   250     RArray< TEfAudioEqualizerBand > iBands;

   251     TInt iBass; // bass level

   252     TInt iTreble; // treble level

   253     TInt iMaxBandLevel;

   254     TInt iMinBandLevel;

   255 };

   256 

   257 #endif // CAMMSEQUALIZERCONTROLGROUP_H

   258 

   259