epoc32/include/icl/exifimagedisplayext.h
branchSymbian2
changeset 2 2fe1408b6811
child 4 837f303aceeb
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/epoc32/include/icl/exifimagedisplayext.h	Tue Mar 16 16:12:26 2010 +0000
     1.3 @@ -0,0 +1,82 @@
     1.4 +// Copyright (c) 2005-2009 Nokia Corporation and/or its subsidiary(-ies).
     1.5 +// All rights reserved.
     1.6 +// This component and the accompanying materials are made available
     1.7 +// under the terms of the License "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members
     1.8 +// which accompanies this distribution, and is available
     1.9 +// at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".
    1.10 +//
    1.11 +// Initial Contributors:
    1.12 +// Nokia Corporation - initial contribution.
    1.13 +//
    1.14 +// Contributors:
    1.15 +//
    1.16 +// Description:
    1.17 +// This is the extension to the plugin API for the Image Display framework
    1.18 +// 
    1.19 +//
    1.20 +
    1.21 +#ifndef EXIFIMAGEDISPLAYEXT_H
    1.22 +#define EXIFIMAGEDISPLAYEXT_H
    1.23 +
    1.24 +#include <e32base.h>
    1.25 +#include <icl/imagedisplaypluginext.h>
    1.26 +#include <icl/exifimagedisplay.hrh>
    1.27 +
    1.28 +const TUid KExifImageDisplayExtensionUid={KUidExifImageDisplayExtension};
    1.29 +
    1.30 +class MExifMetadataReader;
    1.31 +
    1.32 +/**
    1.33 +This class extends the functionality of the Image Display Library client API defined 
    1.34 +in the class CImageDisplay. This extension is supported only by the EXIF-specific framework
    1.35 +plug-ins. In order to invoke the extended functionality, the user needs to call the 
    1.36 +CImageDisplay::ExtensionInterface( ) with the KExifImageDisplayExtensionUid interface UID
    1.37 +and an interface pointer to the object of this class.
    1.38 +
    1.39 +@publishedAll
    1.40 +@released
    1.41 +*/
    1.42 +class MExifImageDisplayExtension :public MImageDisplayPluginExtension
    1.43 +	{
    1.44 +public:
    1.45 +	/**
    1.46 +	Obtains an MExifMetadataReader that can be used to access the EXIF metadata of the image.
    1.47 +	@param aPtr A reference to a pointer to the MExifMetadataReader that can be used to access the EXIF
    1.48 +				metadata of the image.
    1.49 +	@return A system-wide error code.
    1.50 +	*/
    1.51 +	virtual TInt GetExifMetadataReader(MExifMetadataReader*& aPtr)=0;
    1.52 +	
    1.53 +	/**
    1.54 +	Sets the level of quality for the scaling algorithm.
    1.55 +	If quality level is not set by calling this function then 
    1.56 +	the fastest/lowest quality algorithm is used.
    1.57 +	Note: This function must be called before calling CImageDisplay::Play()
    1.58 +	
    1.59 +	@param aQualityLevel Quality level value for the scaling algorithm.
    1.60 +				See CBitmapScaler::TQualityAlgorithm for a set of possible values.
    1.61 +	@return A system-wide error code.
    1.62 +	*/	
    1.63 +	virtual TInt SetScaleQuality(TInt aQualityLevel)=0;
    1.64 +	
    1.65 +	/**
    1.66 +	Sets the maximum quality reduction factor for image decoding.
    1.67 +	By default, the plug-in calculates an optimal maximum reduction factor 
    1.68 +	and uses it to produce a series of roughly-decoded images, passing each of 
    1.69 +	them to the observer interface with the CImageDisplayPlugin::EStatusPartialFrame flag set.
    1.70 +	Note: This function must be called before calling CImageDisplay::Play().
    1.71 +	
    1.72 +	@param aMaxReductionFactor
    1.73 +				The maximum quality reduction factor.
    1.74 +				Usually the maximum reduction can be specfied in range of 0-3.
    1.75 +				A value of 0 means no quality reduction is allowed, so a full-quality image will be decoded as the first frame.
    1.76 +				A value of 1 means (1/2)^1=1/2 of the original image quality. 
    1.77 +				A value of 3 means (1/2)^3=1/8 of the original image quality. 
    1.78 +				If the reduction factor is not set by calling this function then
    1.79 +				the reduction factor value of 3 is used for jpeg images.
    1.80 +	@return KErrArgument if the aMaxReductionFactor parameter is not in the supported range, or a system-wide error code.
    1.81 +	*/	
    1.82 +	virtual TInt SetMaximumReductionFactor(TInt aMaxReductionFactor)=0;
    1.83 +	};
    1.84 +
    1.85 +#endif // EXIFIMAGEDISPLAYEXT_H