#include <BitmapTransforms.h>
Link against: bitmaptransforms.lib

Class `CBitmapScaler`

class CBitmapScaler : public CBase;

Description

The public API for clients to call the BitmapTransforms Library bitmap scaling.

Derivation

CBase - Base class for all classes to be instantiated on the heap.

CBitmapScaler - The public API for clients to call the BitmapTransforms Library bitmap scaling.

Members

Defined in CBitmapScaler:

Cancel()Cancel any outstanding activity.
CustomCommand(TUid,TAny *)Provides custom command capabilties on CBitmapScaler. The command is dispatched ...
DisablePostProcessing(TBool) SetPostProcessing
EMaximumQualitySlowest/highest quality
EMediumQualityMiddle range speed/middle range quality
EMinimumQualityFastest/lowest quality
NewL()Constructs a CBitmapScaler object.
Scale(TRequestStatus *,CFbsBitmap &,CFbsBitmap &,TBool)Begins the bitmap re-scaling operation.
Scale(TRequestStatus *,CFbsBitmap &,const TSize &,TBool)Begins the bitmap re-scaling operation.
SetQualityAlgorithm(TQualityAlgorithm) SetQualityAlgorithm
TQualityAlgorithmAn enumeration to specify the level of quality algorithm.
UseLowMemoryAlgorithm(TBool) UseLowMemory
~CBitmapScaler()This is the destructor for the CBitmapScaler and is responsible for deallocating...

Inherited from CBase:

Delete(CBase *)Deletes the specified object.
Extension_(TUint,TAny *&,TAny *)Extension function
operator new(TUint)Allocates the object from the heap and then initialises its contents to binary z...
operator new(TUint,TAny *)Initialises the object to binary zeroes.
operator new(TUint,TLeave)Allocates the object from the heap and then initialises its contents to binary z...
operator new(TUint,TLeave,TUint)Allocates the object from the heap and then initialises its contents to binary z...
operator new(TUint,TUint)Allocates the object from the heap and then initialises its contents to binary z...

Construction and destruction

`NewL()`

IMPORT_C static CBitmapScaler* NewL();

Description

Constructs a CBitmapScaler object.

Return value

CBitmapScaler *

A pointer to a CBitmapScaler object.

`~CBitmapScaler()`

IMPORT_C ~CBitmapScaler();

Description

This is the destructor for the CBitmapScaler and is responsible for deallocating all resources alloctaed by the CBitmapScaler.

Member functions

`Scale(TRequestStatus *,CFbsBitmap &,CFbsBitmap &,TBool)`

IMPORT_C void Scale(TRequestStatus *aRequestStatus, CFbsBitmap &aSrcBitmap, CFbsBitmap &aTgtBitmap, TBool aMaintainAspectRatio=ETrue);

Description

Begins the bitmap re-scaling operation.

The scaling factor is based on the relative sizes of the source and target bitmaps. The operation is asynchronous. KErrOverFlow status is set if the sizes of input bitmaps are too large for the algorithm to handle.

Post-Condition

The result of the operation is pointed to by aRequestStatus.

Parameters

`TRequestStatus *aRequestStatus`	On return, contains a pointer to the completion status of the rescale of the bitmap.
`CFbsBitmap &aSrcBitmap`	The bitmap to be re-scaled.
`CFbsBitmap &aTgtBitmap`	The target location for the re-scaled bitmap.
`TBool aMaintainAspectRatio`	A boolean indicating if the aspect ratio is maintained. ETrue means the aspect ratio is retained; this is the default. The same scaling factor is applied in both the horizontal and vertical directions. This is the smaller of the horizontal scaling factor and the vertical scaling factor. EFalse means the aspect ratio need not be retained.

`Scale(TRequestStatus *,CFbsBitmap &,const TSize &,TBool)`

IMPORT_C void Scale(TRequestStatus *aRequestStatus, CFbsBitmap &aBitmap, const TSize &aDestinationSize, TBool aMaintainAspectRatio=ETrue);

Description

Begins the bitmap re-scaling operation.

The scaling factor is based on the relative value of the source bitmap size and the explicitly supplied size. The operation is asynchronous. When it is complete, successfully or otherwise, the TRequestStatus is set, passing the state of the operation. KErrOverFlow status is set if the sizes of input bitmaps are too large for the algorithm to handle.

Parameters

`TRequestStatus *aRequestStatus`	On return, contains a pointer to the completion status of the rescale of the bitmap.
`CFbsBitmap &aBitmap`	The bitmap to be re-scaled. This reference is also the target location for the re-scaled bitmap.
`const TSize &aDestinationSize`	The requested target size for the re-scaled bitmap.
`TBool aMaintainAspectRatio`	A boolean indicating if the aspect ratio is maintained. ETrue means the aspect ratio is retained; this is the default. The same scaling factor is applied in both the horizontal and vertical directions. This is the smaller of the horizontal scaling factor and the vertical scaling factor. EFalse means the aspect ratio need not be retained.

`Cancel()`

IMPORT_C void Cancel();

Description

Cancel any outstanding activity.

`CustomCommand(TUid,TAny *)`

IMPORT_C TInt CustomCommand(TUid aUid, TAny *aParam);

Pre-Condition

When a command requires parameters aParam is not NULL.

Description

Provides custom command capabilties on CBitmapScaler. The command is dispatched on aUid and if the command is not known KErrNotSupported will be returned. This function is synchronous.

The Default implementation will support one command to enable and disable post processing on the scale operation The uid of this command is published in the header file. Changes to the status of Post Processing Enabled will become effective only after an exising scaling operation has completed.

Parameters

`TUid aUid`	The ID of the command.
`TAny *aParam`	The command specific information.

Return value

TInt

`DisablePostProcessing(TBool)`

inline TInt DisablePostProcessing(TBool aState);

Description

SetPostProcessing

Parameters


                                 						TBool aState

a boolean flag which if true will set post processing on (Note by defualt the scaler has post processing on)

Return value


                                 						TInt

`UseLowMemoryAlgorithm(TBool)`

inline TInt UseLowMemoryAlgorithm(TBool aState);

Description

UseLowMemory

Parameters


                                 						TBool aState

a boolean flag which if true will enable the low memory algorithm (Note by defualt the scaler does not use the low memory algorithm)

Return value


                                 						TInt

`SetQualityAlgorithm(TQualityAlgorithm)`

inline TInt SetQualityAlgorithm(TQualityAlgorithm aQualityLevel);

Description

SetQualityAlgorithm

Parameters


                                 						CBitmapScaler::TQualityAlgorithm aQualityLevel

an enumeration which sets the quality algorithm

Return value


                                 						TInt

Member enumerations

Enum `TQualityAlgorithm`

TQualityAlgorithm

Description

An enumeration to specify the level of quality algorithm.

`EMinimumQuality`	Fastest/lowest quality
`EMediumQuality`	Middle range speed/middle range quality
`EMaximumQuality`	Slowest/highest quality

Class CBitmapScaler

Description

Derivation

Members

Construction and destruction

NewL()

Description

Return value

~CBitmapScaler()

Description

Member functions

Scale(TRequestStatus *,CFbsBitmap &,CFbsBitmap &,TBool)

Description

Post-Condition

Parameters

Scale(TRequestStatus *,CFbsBitmap &,const TSize &,TBool)

Description

Parameters

Cancel()

Description

CustomCommand(TUid,TAny *)

Pre-Condition

Description

Parameters

Return value

DisablePostProcessing(TBool)

Description

Parameters

Return value

UseLowMemoryAlgorithm(TBool)

Description

Parameters

Return value

SetQualityAlgorithm(TQualityAlgorithm)

Description

Parameters

Return value

Member enumerations

Enum TQualityAlgorithm

Description

Class `CBitmapScaler`

`NewL()`

`~CBitmapScaler()`

`Scale(TRequestStatus *,CFbsBitmap &,CFbsBitmap &,TBool)`

`Scale(TRequestStatus *,CFbsBitmap &,const TSize &,TBool)`

`Cancel()`

`CustomCommand(TUid,TAny *)`

`DisablePostProcessing(TBool)`

`UseLowMemoryAlgorithm(TBool)`

`SetQualityAlgorithm(TQualityAlgorithm)`

Enum `TQualityAlgorithm`