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We’re eternally grateful tohim for his contributions throughout the project, and to Adi for her initialwork on the book. We’d also like to thank all the reviewers, who gaveexemplary feedback under tight deadlines. Thanks Mike, Patrick, James,Roman, Brian, Petteri, Gábor, Pamela, Les and Anthony. We’d also liketo acknowledge Magnus Ingelsten and Fadi Abbas from Scalado, for theirreview of Chapter 3, and Andrew Till of Motorola, for contributing theForeword.Thanks also go to Annabel Cooke for the images used in Chapter 1and to Lane Roberts, for acting as official archivist, and casting his mindback in time to the days of the media server.It’s been a huge project, with many people involved.

If we’ve missedthanking anyone here, we apologize. You know who you are, and thankyou!Code Conventions and NotationsFor you to get the most out of this book, let’s quickly run through thenotation we use. The text is straightforward and where we quote examplecode, resource files or project definition files, they will be highlighted asfollows:This is example code;Symbian C++ uses established naming conventions. We encourageyou to follow them in order for your own code to be understood mosteasily by other Symbian OS developers, and because the conventionshave been chosen carefully to reflect object cleanup and ownership,and to make code more comprehensible. An additional benefit of usingthe conventions is that your code can then be tested with automaticcode-analysis tools that can flag potential bugs or areas to review.If you are not familiar with them, the best way to get used to theconventions is to look at code examples in this book and those providedwith your chosen SDK.CapitalizationThe first letter of class names is capitalized:class TColor;xxviCODE CONVENTIONS AND NOTATIONSThe words making up variable, class or function names are adjoining,with the first letter of each word capitalized.

Classes and functions havetheir initial letter capitalized while, in contrast, function parameters, local,global and member variables have a lower case first letter.Apart from the first letter of each word, the rest of each word is givenin lower case, including abbreviations. For example:void CalculateScore(TInt aCorrectAnswers, TInt aQuestionsAnswered);class CActiveScheduler;TInt localVariable;CShape* iShape;class CBbc;//Abbreviations are not usually written in upper casePrefixesMember variables are prefixed with a lower case ‘i’ which stands for‘instance’:TInt iCount;CBackground* iBitmap;Parameters are prefixed with a lower case ‘a’ which stands for ‘argument’:void ExampleFunction(TBool aExampleBool, const TDesC& aName);We do not use ‘an’ for arguments that start with a vowel: TBoolaExampleBool rather than TBool anExampleBool.Local variables have no prefix:TInt localVariable;CMyClass* ptr = NULL;Class names should be prefixed with the letter appropriate to theirSymbian OS type (usually ‘C’, ‘R’, ‘T’ or ‘M’):classclassclassclassCActive;TParse;RFs;MCallback;CODE CONVENTIONS AND NOTATIONSxxviiConstants are prefixed with ‘K’:const TInt KMaxFilenameLength = 256;#define KMaxFilenameLength 256Enumerations are simple types and so are prefixed with ‘T’.

Enumeration members are prefixed with ‘E’:enum TWeekdays {EMonday, ETuesday, ...};SuffixesA trailing ‘L’ on a function name indicates that the function may leave:void AllocL();A trailing ‘C’ on a function name indicates that the function returns apointer that has been pushed onto the cleanup stack:CCylon* NewLC();A trailing ‘D’ on a function name means that it will result in thedeletion of the object referred to by the function.TInt ExecuteLD(TInt aResourceId);UnderscoresUnderscores are avoided in names except in macros (__ASSERT_DEBUG)or resource files (MENU_ITEM).Code LayoutThe curly bracket layout convention in Symbian OS code, used throughout this book, is to indent the bracket as well as the following statement:xxviiiCODE CONVENTIONS AND NOTATIONSvoid CNotifyChange::StartFilesystemMonitor(){ // Only allow one request to be submitted at a time// Caller must call Cancel() before submitting anotherif (IsActive()){_LIT(KAOExamplePanic, "CNotifyChange");User::Panic(KAOExamplePanic, KErrInUse);}iFs.NotifyChange(ENotifyAll, iStatus, *iPath);SetActive(); // Mark this object active}1Introduction1.1 The Convergence DeviceConvergence has been one of the major technology trends of the lastdecade.

Like all trends, its roots go back much further; in this case youwould probably trace them back to the first combination of computing andcommunications technologies that led to the birth of the Internet. Humaninteractions that had previously taken place via the physical transportationof paper could now occur almost instantaneously to any connectedcomputer in the world. Increases in computing power, digital storagecapacity and communications bandwidth then enabled more complexmedia – such as voice, music, high resolution images and video – toenter this digital world. Today, near instant global communicationsare available in multiple media, or multimedia, as they’re commonlydescribed.At the same time this was happening, communications were shiftingfrom fixed wires to mobile radio technologies, allowing people to connectwith one another from anywhere. Computing has become increasinglyportable, freeing users to work and play on the move.

Imaging and videoconverged with computing to give us digital cameras and camcorders.Music and video distribution and storage have gone first digital andthen portable. Global positioning technology combined with portablecomputing has brought us personal navigation devices. Almost inevitably,miniaturization and integration have led to the development of theultimate convergence device – the multimedia smartphone.The term ‘smartphone’ was first applied to devices which combinedthe features of a mobile phone and a Personal Digital Assistant (PDA).As technology has advanced, that functionality is now available in somefairly low-end models.

In response, the definition of what constitutes asmartphone has changed over time. High-end models are now differentiated with additional features, including hardware-accelerated graphicsand video, multi-megapixel cameras, GPS and more sophisticated and2INTRODUCTIONintuitive input methods – smartphones are getting smarter! Symbiancurrently defines a smartphone as:a mobile phone that uses an operating system based on industry standards,designed for the requirements of advanced mobile telephony communication on 2.5G networks or above.The key distinction between a smartphone and a less capable ‘featurephone’ is the operating system.

A smartphone operating system is capableof supporting the installation of native applications after the device hasbeen purchased. Examples of smartphones include devices based onSymbian OS and Microsoft Windows Mobile as well as RIM’s BlackBerrydevices and Apple’s iPhone.Smartphones are often referred to as the Swiss Army knives of theconsumer electronics world – they have multiple functions, as Figure 1.1shows. Arguably, the screen size of current smartphones isn’t ideal forweb browsing or viewing pictures and videos, the input methods arelimited and the quality of camera optics and speakers are constrainedby the size of the device. However, there are massive advantages incost and in having all of these functions available at any time in asingle device.

Unlike the humble Swiss Army knife, the smartphone isprogrammable – enabling new synergies and combinations of features notFigure 1.1 Some of the functions of a typical convergence device: taking still and videoimages, playing music and radio, navigating by GPS, browsing the web and, of course,making voice calls and SMSTRANSFORMATION OF THE MEDIA INDUSTRY3possible on separate devices.

For example, you can discover, purchaseand download new music and video content direct to your device; ablogger, social network user or Internet journalist can capture, compose,upload and view content with a single gadget – no need to transferbetween devices or convert between formats. Better still, because mostsmartphones are open to third-party software, you can customize yourdevice and add new features throughout its life as new technologies andservices become available.When discussing the importance and utility of the smartphone, it is certainly worth considering the developing world.

When current smartphoneusers evaluate devices their perceptions are shaped by their experienceswith the Internet on a PC, video on their televisions and DVD players,music on their home stereos and possibly photography on a high-endcamera or camcorder. In contrast to that, there are many hundreds ofmillions of people whose first experiences of the Internet have been, orwill be, on a mobile phone. As devices become cheaper and today’s latestmodel is replaced with something more powerful it seems very likely that,for many of those same people, their first experiences of television, photography and other applications will be on today’s smartphones. Perhapssome will even be able to share their world and perspectives with a wideraudience for the first time.Although it’s easy for most users to take new technology for grantedafter a very short time, it isn’t only engineers, enthusiasts and thosewho’ve skipped earlier generations of technology who can get excitedabout the multimedia capabilities of smartphones – mobile multimedia isbig business too!1.2 Transformation of the Media IndustryThe media industry is familiar with disruptive technologies coming alongand changing its business models.