Audio & VideoiOS App DevelopmentFall 2010 — Lecture 19

Questions?

Announcements

• Assignment #5 — due Monday by 11:59pm

Today’s Topics

• Core Audio Components

• Playing Short Sounds

• Vibrating the Phone

• Playing Long Sounds

• Recording Audio

• Playing Video

Notes

• I’m showing the relevant portions of the view controller interfaces and implementations in these notes

• Remember to release relevant memory in the -dealloc methods — they are not shown here

• You will also need to wire up outlets and actions in IB

• Where delegates or data sources are used, they too require wiring in IB

Notes

• There’s not much (if any) error handling in the examples

• You should probably consult the documentation and look at Apple’s examples for appropriate handling techniques

Core Audio

Core Audio

• High level, easy to use

• System Sound API — short sounds

• AVAudioPlayer class — ObjC, simple API

• Lower level, takes more effort but much more control

• Audio Toolbox — recording and playback, streaming, full control

• Audio Units — processing audio

• OpenAL — 3D positional sound

• Which one you use depends on what you’re trying to do

OS Management

• The OS manages the sound system

• You can ask for behavior but the OS has control

• May preempt your audio if it sees fit

Converting Sounds

• OS X provides a command line utility called afconvert that allows you to convert between sound formats

• Supports wide variety of input and output formats

• Easily convert sounds to System Sounds formats

• Run with “-h” flag for help and usage

/usr/bin/afconvert -f aiff -d BEI16 input.mp3 output.aif

Playing Short Sounds

Playing Short Sounds

• We’re talking less than 30 seconds

• Intended for user-interface sound effects and user alerts

• It is not intended for sound effects in games

• Very simple C-based API — trades features for ease-of-use

• No looping

• No volume control

• Immediate playback

• Limited set of formats

• Linear PCM or IMA4

• In .caf, .aif or .wav file

Playing Short Sounds

• General process...

• Register the sound and get a “Sound ID”

• Play the sound — based on Sound ID

• Optionally register a callback for when sound has completed playing

• Dispose of Sound ID when finished

System Sounds Functions

• The following C-function creates a system sound from the specified reference and sets the sound ID (a handle) to the sound in the second argument (passed by reference)...

• To call the sound, simply call this function with the ID...

• Then to release the sound, pass the sound ID into dispose...

OSStatus AudioServicesCreateSystemSoundID(CFURLRef inFileURL, SystemSoundID* outSystemSoundID);

OSStatus AudioServicesDisposeSystemSoundID(SystemSoundID inSystemSoundID);

void AudioServicesPlaySystemSound(SystemSoundID inSystemSoundID);

BellViewController.xib

• In IB, we’ll create a button that allows us to play the sound

• Button wired up to play action

• We’ll also add and wire up an image view for dramatic effect

ShortSoundViewController.h

#import <UIKit/UIKit.h>#import <AudioToolbox/AudioToolbox.h>

@interface ShortSoundViewController : UIViewController {

! SystemSoundID sound;

}

@property(nonatomic, retain) IBOutlet UIImageView *imageView;

- (IBAction)play;

@end

Need to add AudioToolbox

framework to project

ShortSoundViewController.m

#import "ShortSoundViewController.h"

@implementation ShortSoundViewController

@synthesize imageView;

- (void)loadSounds {!! CFBundleRef mainBundle = CFBundleGetMainBundle();!! // Get the URL to the sound file to play. The file in this case is "bell.wav"! CFURLRef soundFileURLRef = CFBundleCopyResourceURL(mainBundle, CFSTR("bell"), ! ! ! ! ! ! ! ! ! ! ! ! ! CFSTR("wav"), NULL);!! // Create a system sound object representing the sound file! AudioServicesCreateSystemSoundID(soundFileURLRef, &sound);!}

- (IBAction)play {! AudioServicesPlaySystemSound(sound);}

/* ... */

ShortSoundViewController.m

/* ... */

- (void)loadImages {! UIImage *bell1 = [UIImage imageNamed:@"bell1"];! UIImage *bell2 = [UIImage imageNamed:@"bell2"];! UIImage *bell3 = [UIImage imageNamed:@"bell3"];! UIImage *bell4 = [UIImage imageNamed:@"bell4"];! self.imageView.animationDuration = .45;! self.imageView.animationImages = [NSArray arrayWithObjects: bell1, bell2, bell3, bell4, nil];! [self.imageView startAnimating];}

- (void)viewDidLoad {! [super viewDidLoad];! [self loadSounds];! [self loadImages];}

- (void)dealloc { ! AudioServicesDisposeSystemSoundID(sound);! self.imageView = nil; [super dealloc];}

@end

The Resulting App

Vibrating the iPhone

Vibrating the iPhone

• The ability to vibrate an iPhone is provided by the system sound API

• iPod touches and iPads do not have vibration hardware, as such playing the “vibration sound” has no effect

• If you choose to use vibration in your app — use it sparingly

• An good use might be in a game if your vehicle blows up

• Excessive use of vibration has been known to be grounds for App Store rejection

Vibrating the iPhone

• To vibrate the phone, you actually use a special predefined sound ID for vibration...

• So, to make the phone vibrate you simply call...

• You have no control over duration

kSystemSoundID_Vibrate

AudioServicesPlaySystemSound(kSystemSoundID_Vibrate);

Simulator Support

• The simulator has no support for vibration

• Again, vibration is only available on iPhones and not iPod touches or iPads

✘

Playing Longer Sounds

AVAudioPlayer

• Play longer sounds of any length

• Locally stored files or in-memory (no network streaming)

• Loop, seek, play, pause

• Provides metering capability

• Play multiple sounds simultaneously

• ObjC API

• Initialize with file URL or data

• AVAudioPlayerDelegate for various life-cycle events

• Supports many additional formats

Playing Longer Sounds

• General process...

• Create file URL

• Allocate an AVAudioPlayer instance

• Optionally set a delegate

• Prepare to play

• Play

• Release the instance when finished

PlayerViewController.xib

• To demonstrate the metering capability we’re going to also use a pre-built metering UIView

• This example uses Chris Adamson’s LevelMeterView

• Licensed under an Apache 2.0 License

LevelMeterViews one for each left and right channels

PlayerViewController.h

#import <UIKit/UIKit.h>#import <AVFoundation/AVFoundation.h>#import "LevelMeterView.h"

@interface PlayerViewController : UIViewController <AVAudioPlayerDelegate> {

}

@property(nonatomic, retain) AVAudioPlayer *player;@property(nonatomic, retain) IBOutlet UIButton *playOrPauseButton;@property(nonatomic, retain) IBOutlet UILabel *durationLabel;@property(nonatomic, retain) IBOutlet UILabel *currentPositionLabel;@property(nonatomic, retain) IBOutlet UIProgressView *currentPositionProgress;@property(nonatomic, retain) IBOutlet UISlider *volumeSlider;@property(nonatomic, retain) IBOutlet LevelMeterView *leftMeter;@property(nonatomic, retain) IBOutlet LevelMeterView *rightMeter;

- (IBAction)playOrPause;- (IBAction)setVolume;

@end

Need to add AVFoundation framework to project

Implement delegate

PlayerViewController.m

#import "PlayerViewController.h"

@implementation PlayerViewController

@synthesize player, playOrPauseButton, durationLabel, currentPositionLabel;@synthesize currentPositionProgress, volumeSlider, leftMeter, rightMeter;

- (NSString *)timeToString:(int)time {! return [NSString stringWithFormat:@"%02d:%02d", time / 60, time % 60];}

- (IBAction)playOrPause {! if (self.player.playing) {! ! [self.playOrPauseButton setImage:[UIImage imageNamed:@"play"] ! ! ! ! ! ! ! ! forState:UIControlStateNormal]; ! ! [self.player pause];! } else {! ! [self.playOrPauseButton setImage:[UIImage imageNamed:@"pause"] ! ! ! ! ! ! ! ! forState:UIControlStateNormal]; ! ! [self.player play];! }}

/* ... */

PlayerViewController.m

/* ... */

- (void)audioPlayerDidFinishPlaying:(AVAudioPlayer *)player successfully:(BOOL)completed { if (completed) { [self.playOrPauseButton setImage:[UIImage imageNamed:@"play"] forState:UIControlStateNormal]; } }

- (IBAction)setVolume { self.player.volume = self.volumeSlider.value;}

- (void)updateDisplay { self.currentPositionProgress.progress = self.player.currentTime / self.player.duration; self.currentPositionLabel.text = [self timeToString:self.player.currentTime]; [self.player updateMeters]; [self.leftMeter setPower:[self.player averagePowerForChannel:0] peak:[self.player peakPowerForChannel:0]]; [self.rightMeter setPower:[self.player averagePowerForChannel:1] peak:[self.player peakPowerForChannel:1]];}

/* ... */

PlayerViewController.m

/* ... */

- (void)viewDidLoad { [super viewDidLoad]; NSString *soundFilePath = [[NSBundle mainBundle] pathForResource:@"sample" ofType:@"mp3"]; NSURL *fileURL = [[[NSURL alloc] initFileURLWithPath: soundFilePath] autorelease]; self.player = [[[AVAudioPlayer alloc] initWithContentsOfURL: fileURL error: nil] autorelease]; [self.player prepareToPlay]; [self.player setDelegate:self]; self.player.volume = .5; self.player.meteringEnabled = YES; self.volumeSlider.value = self.player.volume; self.currentPositionLabel.text = @"0:00"; self.durationLabel.text = [self timeToString:self.player.duration]; // fire updates [self updateDisplay]; [NSTimer scheduledTimerWithTimeInterval:.1 target:self selector:@selector(updateDisplay) userInfo:nil repeats:YES];}/* ... */

@end

The Resulting App

Other Sound Playing APIs

Audio Toolbox

• Recording audio

• Audio Queue Services

• Create a queue

• Define a callback function to receive recorded audio data

• Start the queue

• Receive callbacks with recorded data, you have to store it

• Stop the queue

• See the “SpeakHere” example project in iPhone Dev Center for an example

Audio Units

• For serious audio processing

• Graph-based audio

• Rate conversion

• Audio effects

• Mixing multiple streams

• Incredibly powerful — same as on Mac OS X

OpenAL

• High level, cross-platform API for 3D audio mixing

• Great for games where you already are defining 3D space

• Mimics OpenGL conventions

• Models audio in 3D space

• Buffers — container for Audio

• Sources — 3D point emitting Audio

• Listener — position where Sources are heard

• For more information visit the OpenAL website

• http://www.openal.org/

Recording Audio

Recoding Audio

• The AVAudioRecorder class provides basic audio recording capability in an ObjC API

• Class also has an AVAudioRecorderDelegate to provide callbacks for certain events (e.g. finished recording)

AVAudioRecorder Capabilities

• Record until the user stops the recording

• Record for a specified duration

• Pause and resume a recording

• Obtain input audio-level data that you can use to provide level metering

• A large image view and two buttons

• Each button has a different normal and selected image

• Each is wired up as outlets and wired to call an action

RecordViewController.xib

RecordViewController.h

#import <UIKit/UIKit.h>#import <AVFoundation/AVFoundation.h>

@interface RecordViewController : UIViewController <AVAudioRecorderDelegate, ! ! ! ! ! ! ! ! ! ! ! ! AVAudioSessionDelegate, AVAudioPlayerDelegate> {

}

@property(nonatomic, retain) AVAudioRecorder *audioRecorder;@property(nonatomic, retain) AVAudioPlayer *audioPlayer;@property(nonatomic, retain) IBOutlet UIButton *recordButton;@property(nonatomic, retain) IBOutlet UIButton *playButton;

- (IBAction)toggleRecord;- (IBAction)togglePlay;

@end

AVFoundation again

RecordViewController.m

#import "RecordViewController.h"#import <CoreAudio/CoreAudioTypes.h>

@implementation RecordViewController

@synthesize audioPlayer, audioRecorder;@synthesize recordButton, playButton;

- (void)audioPlayerDidFinishPlaying:(AVAudioPlayer *)player successfully:(BOOL)completed { if (completed) { self.playButton.selected = NO; }}

- (NSURL *)getSoundURL { NSArray *segments = [NSArray arrayWithObjects:NSHomeDirectory(), @"Documents", @"recording.caf", nil]; NSString *soundFilePath = [NSString pathWithComponents:segments]; return [[[NSURL alloc] initFileURLWithPath: soundFilePath] autorelease];!}

/* ... */

RecordViewController.m

/* ... */

- (void)setupAudioSession { AVAudioSession *audioSession = [AVAudioSession sharedInstance]; audioSession.delegate = self; [audioSession setActive:YES error: NULL]; [audioSession setCategory:AVAudioSessionCategoryPlayAndRecord error:NULL];!}

- (void)tearDownAudioSession { [[AVAudioSession sharedInstance] setActive:NO error:NULL];}

/* ... */

RecordViewController.m

/* ... */

- (void)setupRecorder {! [self setupAudioSession];! // allocate a recorder for use NSDictionary *recordSettings = [NSDictionary dictionaryWithObjectsAndKeys: [NSNumber numberWithFloat: 44100.0], AVSampleRateKey, [NSNumber numberWithInt: kAudioFormatAppleLossless], AVFormatIDKey, [NSNumber numberWithInt: 1], AVNumberOfChannelsKey, [NSNumber numberWithInt: AVAudioQualityMax], AVEncoderAudioQualityKey, nil]; self.audioRecorder = [[AVAudioRecorder alloc] initWithURL: [self getSoundURL] settings: recordSettings error: NULL]; self.audioRecorder.delegate = self; [self.audioRecorder prepareToRecord];}

/* ... */

RecordViewController.m

/* ... */

- (IBAction)toggleRecord { if (self.recordButton.selected) { [self tearDownAudioSession]; [self.audioRecorder stop]; } else { [self setupAudioSession]; [self.audioRecorder record]; } self.recordButton.selected = !self.recordButton.selected;}

/* ... */

RecordViewController.m

/* ... */

- (IBAction)togglePlay { if (self.playButton.selected) { [self tearDownAudioSession]; [self.audioPlayer stop]; } else { [self setupAudioSession]; self.audioPlayer = [[[AVAudioPlayer alloc] initWithContentsOfURL:[self getSoundURL] error:NULL] autorelease]; self.audioPlayer.delegate = self; [self.audioPlayer prepareToPlay]; [self.audioPlayer play];! ! ! } self.playButton.selected = !self.playButton.selected;}

- (void)viewDidLoad { [super viewDidLoad]; [self setupRecorder];}

/* ... */

@end

The Resulting App

Playing Video

MPMoviePlayerController

• The MPMoviePlayerController provides several different video playback options

• Playback styles — full screen or render in a view

• Video source

• Can play back movies stored in your application’s bundle, Document, or temp directories

• Can also play movies and audio files loaded from a network-based URL

• Note: prior to iOS 3.2 only full-screen playback was supported

MPMoviePlayerController

• Has many properties/methods that allow you to change the appearance and behavior of the movie playback

• A sampling of some of the more common ones are shown below...

- (NSURL *)contentURL;- (void)setContentURL:(NSURL *)contentURL;

// The style of the playback controls. // Defaults to MPMovieControlStyleDefault.@property(nonatomic) MPMovieControlStyle controlStyle;

// Determines how the movie player repeats when reaching // the end of playback. Defaults to MPMovieRepeatModeNone.@property(nonatomic) MPMovieRepeatMode repeatMode;

// Determines if the movie is presented in the entire screen // (obscuring all other application content). Default is NO.// Setting this property to YES before the movie player's view// is visible will have no effect.@property(nonatomic, getter=isFullscreen) BOOL fullscreen;- (void)setFullscreen:(BOOL)fullscreen animated:(BOOL)animated;

MPMovieControlStyle

• Different playback controls...

enum { MPMovieControlStyleNone, // No controls MPMovieControlStyleEmbedded, // Controls for an embedded view MPMovieControlStyleFullscreen, // Controls for fullscreen playback MPMovieControlStyleDefault = MPMovieControlStyleEmbedded};typedef NSInteger MPMovieControlStyle;

MPMediaPlayback

• MPMoviePlayerController adopts the MPMediaPlayback protocol

@protocol MPMediaPlayback

- (void)prepareToPlay;

@property(nonatomic, readonly) BOOL isPreparedToPlay;

- (void)play;- (void)pause;- (void)stop;

@property(nonatomic) NSTimeInterval currentPlaybackTime;

@property(nonatomic) float currentPlaybackRate;

- (void)beginSeekingForward;- (void)beginSeekingBackward;- (void)endSeeking;

@end

Examples

• Let’s look at 2 different use cases...

• A short in-app video — applicable for...

• In-app help

• Cut-scene sequences in games

• Loading fullscreen video from a website — applicable for...

• Content changes regularly

• Too large to reasonably bundle in app

• Live streaming Streaming

In-App Video

In-App Video

• Let’s simulate a cut-scene sequence in a game...

• Turn down lights (fade to black)

• Load content from a local source

• Play in-line within application

• When done playing, turn up lights

• This in-app video will have no user facing playback controls

VideoViewController.xib

• Fairly simple NIB

• A button wired up to an outlet

• Will call an action method

VideoViewController.h

#import <UIKit/UIKit.h>#import <MediaPlayer/MediaPlayer.h>

@interface VideoViewController : UIViewController {! int level;}

@property(nonatomic, retain) MPMoviePlayerController *player;@property(nonatomic, retain) IBOutlet UIButton *button;@property(nonatomic, retain) UIView *overlayView;

- (IBAction)playMovie;

@end

Need to add MediaPlayer Framework

VideoViewController.m

#import "VideoViewController.h"

@implementation VideoViewController

@synthesize player, button, overlayView;

- (IBAction)playMovie {! // if first time through, set everything up if (!self.overlayView) {! // create and configure view self.overlayView = [[[UIView alloc] initWithFrame:self.view.bounds] autorelease]; self.overlayView.backgroundColor = [UIColor clearColor];! ! /* ... */

Programmatically create a clear UIView the same size as the view controller’s view

VideoViewController.m

/* ... */

// prep video NSString *videoPath = [[NSBundle mainBundle] pathForResource:@"big-buck-bunny" ofType:@"m4v"]; NSURL *videoURL = [NSURL fileURLWithPath: videoPath]; self.player = [[[MPMoviePlayerController alloc] initWithContentURL: videoURL] autorelease]; self.player.controlStyle = MPMovieControlStyleNone; [[self.player view] setFrame: [self.overlayView bounds]];! ! // register for notification when movie is done playing [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(playbackFinished:)! !! ! ! ! ! ! ! ! name:@"MPMoviePlayerPlaybackDidFinishNotification" object:nil];! ! ! ! // speed up movie - useful for debugging // self.player.currentPlaybackRate = 2.0;! }

/* ... */

Create the video player

with no controls & add to overlay

Use the notification center to get a notification when playback has completed

VideoViewController.m

/* ... */

// add overlay view [self.view addSubview:self.overlayView];! // animate in then start playing video [UIView animateWithDuration:2.0 animations:^ { self.overlayView.backgroundColor = [UIColor blackColor]; } completion:^ (BOOL finished) { [self.overlayView addSubview: [self.player view]]; [self.player play];! }];}

/* ... */

Add clear overlay to view, fade to black, then add player to overlay and start playback

VideoViewController.m

/* ... */

- (void)playbackFinished:(NSNotification*)notification {! // update background scene NSString *buttonTitle = [NSString stringWithFormat:@"Go onto level %d", ++level + 1]; [self.button setTitle:buttonTitle forState:UIControlStateNormal];! // remove player from overlay [[self.player view] removeFromSuperview];! // animate out then remove overlay [UIView animateWithDuration:2.0 animations:^ { self.overlayView.backgroundColor = [UIColor clearColor]; } completion:^ (BOOL finished) { [self.overlayView removeFromSuperview]; }];}

/* ... */

@end

When playback has finished, remove player from view, fade

up and remove overlay

The Resulting App

Full-Screen Video

Full-Screen Video

• You can also easily do full-screen video from within your app

• You could do this by packing a MPMoviePlayerController view into a view controller where it takes up the whole screen and push it onto the view controller stack

• It turns out that this is a common enough of an operation that Apple provided a view controller class to do just that...

MPMoviePlayerViewController

• MPMoviePlayerViewController class wraps up a player into a view controller

• Can access the underlaying player via a property...

• Method to init with a given video...

• Also extends UIView with the following 2 methods...

- (id)initWithContentURL:(NSURL *)contentURL;

@property(nonatomic, readonly) MPMoviePlayerController *moviePlayer;

- (void)presentMoviePlayerViewControllerAnimated: (MPMoviePlayerViewController *)moviePlayerViewController;- (void)dismissMoviePlayerViewControllerAnimated;

Full Screen Video App

• Let’s simulate being able to browse a list of videos online and selecting one for viewing

• Table view with selections

• Tap to play

• Video will play fullscreen

• When done playing, return to list

RootViewController.h

#import <UIKit/UIKit.h>#import <MediaPlayer/MediaPlayer.h>

@interface RootViewController : UITableViewController {! NSMutableArray * videos;}

@property(nonatomic, retain) MPMoviePlayerViewController *playerController;

@end

RootViewController.m

#import "RootViewController.h"

@implementation RootViewController

@synthesize playerController;

#pragma mark -#pragma mark View lifecycle

- (void)viewDidLoad {! self.title = @"Videos";!! // might load data from some other online resource! // here we'll just load from the local file system! NSString *plist = [[NSBundle mainBundle] pathForResource:@"videos" ! ! ! ! ! ! ! ! ! ! ! ! ! ofType:@"plist"];! videos = [[NSArray alloc] initWithContentsOfFile:plist];!! // create an instance of the movie player! self.playerController = [[[MPMoviePlayerController alloc] init] autorelease];}

/* ... */

RootViewController.m

/* ... */

#pragma mark -#pragma mark Table view data source

// Customize the number of sections in the table view.- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { return 1;}

// Customize the number of rows in the table view.- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return [videos count];}

/* ... */

RootViewController.m

/* ... */

// Customize the appearance of table view cells.- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"Cell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease]; cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator; } // Configure the cell. NSDictionary *video = [videos objectAtIndex:indexPath.row]; cell.textLabel.text = [video objectForKey:@"title"]; NSURL *url = [NSURL URLWithString:[video objectForKey:@"image"]]; NSData *data = [NSData dataWithContentsOfURL:url]; cell.imageView.image = [UIImage imageWithData:data]; return cell;}

/* ... */

RootViewController.m

/* ... */

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { ! NSString *urlString = [[videos objectAtIndex:indexPath.row] objectForKey:@"video"];! NSURL *url = [NSURL URLWithString:urlString];! self.playerController = [[[MPMoviePlayerViewController alloc] initWithContentURL:url] autorelease];! [self presentMoviePlayerViewControllerAnimated: self.playerController];!}

/* ... */

@end

The Resulting App

Additional Resources

• Audio Session Programming Guide• http://developer.apple.com/library/ios/documentation/

Audio/Conceptual/AudioSessionProgrammingGuide/• Core Audio Overview

• http://developer.apple.com/library/ios/documentation/MusicAudio/Conceptual/CoreAudioOverview/

• Audio Queue Services Programming Guide• http://developer.apple.com/library/ios/documentation/

MusicAudio/Conceptual/AudioQueueProgrammingGuide/• Audio & Video Coding How-To's

• http://developer.apple.com/library/ios/codinghowtos/AudioAndVideo/

For Next Class

• UIWebView Class Reference• http://developer.apple.com/library/ios/documentation/

UIKit/Reference/UIWebView_Class/• MFMailComposeViewController Class Reference

• http://developer.apple.com/library/ios/documentation/MessageUI/Reference/MFMailComposeViewController_class/

• Concurrency Programming Guide

• http://developer.apple.com/library/ios/documentation/General/Conceptual/ConcurrencyProgrammingGuide/

For Next Class

• CFNetwork Programming Guide• http://developer.apple.com/library/ios/

DOCUMENTATION/Networking/Conceptual/CFNetwork/

• cocoahttpserver on Google Code

• http://code.google.com/p/cocoahttpserver/

• iOS Man pages (for BSD sockets)

• http://developer.apple.com/library/ios/documentation/System/Conceptual/ManPages_iPhoneOS/