Added methods to AudioStreamer to allow level metering, and a very ba…

…sic metering view to demonstrate usage

Conflicts:

	Classes/AudioStreamer.h

Classes/AudioStreamer.h

@@ -159,6 +159,17 @@ extern NSString * const ASPresentAlertWithTitleNotification;
 								// time)
 	double packetDuration;		// sample rate times frames per packet
 	double lastProgress;		// last calculated progress point
+	UInt32 numberOfChannels;	// Number of audio channels in the stream (1 = mono, 2 = stereo)
+
+#ifdef SHOUTCAST_METADATA
+	BOOL foundIcyStart;
+	BOOL foundIcyEnd;
+	BOOL parsedHeaders;
+	unsigned int metaDataInterval;					// how many data bytes between meta data
+	unsigned int metaDataBytesRemaining;	// how many bytes of metadata remain to be read
+	unsigned int dataBytesRead;							// how many bytes of data have been read
+	NSMutableString *metaDataString;			// the metaDataString
+#endif
 }
 
 @property AudioStreamerErrorCode errorCode;
@@ -167,6 +178,9 @@ extern NSString * const ASPresentAlertWithTitleNotification;
 @property (readonly) double duration;
 @property (readwrite) UInt32 bitRate;
 @property (readonly) NSDictionary *httpHeaders;
+@property (readonly) UInt32 numberOfChannels;
+@property (assign, getter=isMeteringEnabled) BOOL meteringEnabled;
+
 
 - (id)initWithURL:(NSURL *)aURL;
 - (void)start;
@@ -179,6 +193,11 @@ extern NSString * const ASPresentAlertWithTitleNotification;
 - (void)seekToTime:(double)newSeekTime;
 - (double)calculatedBitRate;
 
+// level metering
+- (float)peakPowerForChannel:(NSUInteger)channelNumber;
+- (float)averagePowerForChannel:(NSUInteger)channelNumber;
+
+
 @end
 
 

Classes/AudioStreamer.m

@@ -219,6 +219,8 @@ @implementation AudioStreamer
 @synthesize state;
 @synthesize bitRate;
 @synthesize httpHeaders;
+@synthesize numberOfChannels;
+
 
 //
 // initWithURL
@@ -1122,6 +1124,68 @@ - (double)duration
 	return (fileLength - dataOffset) / (calculatedBitRate * 0.125);
 }
 
+
+//
+// isMeteringEnabled
+//
+
+- (BOOL)isMeteringEnabled {
+	UInt32 enabled;
+	UInt32 propertySize = sizeof(UInt32);
+	OSStatus status = AudioQueueGetProperty(audioQueue, kAudioQueueProperty_EnableLevelMetering, &enabled, &propertySize);
+	if(!status) {
+		return (enabled == 1);
+	}
+	return NO;
+}
+
+
+//
+// setMeteringEnabled
+//
+
+- (void)setMeteringEnabled:(BOOL)enable {
+	if(enable == [self isMeteringEnabled])
+		return;
+	UInt32 enabled = (enable ? 1 : 0);
+	OSStatus status = AudioQueueSetProperty(audioQueue, kAudioQueueProperty_EnableLevelMetering, &enabled, sizeof(UInt32));
+	// do something if failed?
+	if(status)
+		return;
+}
+
+
+// level metering
+- (float)peakPowerForChannel:(NSUInteger)channelNumber {
+	if(![self isMeteringEnabled] || channelNumber >= [self numberOfChannels])
+		return 0;
+	float peakPower = 0;
+	UInt32 propertySize = [self numberOfChannels] * sizeof(AudioQueueLevelMeterState);
+	AudioQueueLevelMeterState *audioLevels = calloc(sizeof(AudioQueueLevelMeterState), [self numberOfChannels]);
+	OSStatus status = AudioQueueGetProperty(audioQueue, kAudioQueueProperty_CurrentLevelMeter, audioLevels, &propertySize);
+	if(!status) {
+		peakPower = audioLevels[channelNumber].mPeakPower;
+	}
+	free(audioLevels);
+	return peakPower;
+}
+
+
+- (float)averagePowerForChannel:(NSUInteger)channelNumber {
+	if(![self isMeteringEnabled] || channelNumber >= [self numberOfChannels])
+		return 0;
+	float peakPower = 0;
+	UInt32 propertySize = [self numberOfChannels] * sizeof(AudioQueueLevelMeterState);
+	AudioQueueLevelMeterState *audioLevels = calloc(sizeof(AudioQueueLevelMeterState), [self numberOfChannels]);
+	OSStatus status = AudioQueueGetProperty(audioQueue, kAudioQueueProperty_CurrentLevelMeter, audioLevels, &propertySize);
+	if(!status) {
+		peakPower = audioLevels[channelNumber].mAveragePower;
+	}
+	free(audioLevels);
+	return peakPower;
+}
+
+
 //
 // pause
 //
@@ -1786,6 +1850,8 @@ - (void)createQueue
 	sampleRate = asbd.mSampleRate;
 	packetDuration = asbd.mFramesPerPacket / sampleRate;
 
+	numberOfChannels = asbd.mChannelsPerFrame;
+
 	// create the audio queue
 	err = AudioQueueNewOutput(&asbd, MyAudioQueueOutputCallback, self, NULL, NULL, 0, &audioQueue);
 	if (err)

Classes/LevelMeterView.h

@@ -0,0 +1,20 @@
+//
+//  LevelMeterView.h
+//  iPhoneStreamingPlayer
+//
+//  Created by Carlos Oliva G. on 07-08-10.
+//  Copyright 2010 iDev Software. All rights reserved.
+//
+
+#import <UIKit/UIKit.h>
+
+
+@interface LevelMeterView : UIView {
+	CGFloat leftValue;
+	CGFloat rightValue;
+}
+
+- (void)updateMeterWithLeftValue:(CGFloat)left rightValue:(CGFloat)right;
+
+
+@end

Classes/LevelMeterView.m

@@ -0,0 +1,51 @@
+//
+//  LevelMeterView.m
+//  iPhoneStreamingPlayer
+//
+//  Created by Carlos Oliva G. on 07-08-10.
+//  Copyright 2010 iDev Software. All rights reserved.
+//
+
+#import "LevelMeterView.h"
+
+#define kMeterViewFullWidth 275.0
+
+@implementation LevelMeterView
+
+
+- (id)initWithFrame:(CGRect)frame {
+    if ((self = [super initWithFrame:frame])) {
+        // Initialization code
+		self.backgroundColor = [UIColor blackColor];
+    }
+    return self;
+}
+
+// Only override drawRect: if you perform custom drawing.
+// An empty implementation adversely affects performance during animation.
+- (void)drawRect:(CGRect)rect {
+    // Drawing code
+	[[UIColor whiteColor] set];
+	[@"L" drawInRect:CGRectMake(0.0, 10.0, 15.0, 15.0) withFont:[UIFont boldSystemFontOfSize:[UIFont systemFontSize]] lineBreakMode:UILineBreakModeWordWrap alignment:UITextAlignmentCenter];
+	[@"R" drawInRect:CGRectMake(0.0, 35.0, 15.0, 15.0) withFont:[UIFont boldSystemFontOfSize:[UIFont systemFontSize]] lineBreakMode:UILineBreakModeWordWrap alignment:UITextAlignmentCenter];
+
+	CGContextRef context = UIGraphicsGetCurrentContext();
+	CGContextSetFillColorWithColor(context, [UIColor greenColor].CGColor);
+	CGContextFillRect(context, CGRectMake(15.0, 10.0, kMeterViewFullWidth * leftValue, 15.0));
+	CGContextFillRect(context, CGRectMake(15.0, 35.0, kMeterViewFullWidth * rightValue, 15.0));
+	CGContextFlush(context);
+}
+
+
+- (void)updateMeterWithLeftValue:(CGFloat)left rightValue:(CGFloat)right {
+	leftValue = left;
+	rightValue = right;
+	[self setNeedsDisplay];
+}
+
+- (void)dealloc {
+    [super dealloc];
+}
+
+
+@end

Classes/iPhoneStreamingPlayerViewController.h

@@ -14,7 +14,7 @@
 
 #import <UIKit/UIKit.h>
 
-@class AudioStreamer;
+@class AudioStreamer, LevelMeterView;
 
 @interface iPhoneStreamingPlayerViewController : UIViewController
 {
@@ -25,6 +25,8 @@
 	IBOutlet UISlider *progressSlider;
 	AudioStreamer *streamer;
 	NSTimer *progressUpdateTimer;
+	NSTimer *levelMeterUpdateTimer;
+	LevelMeterView *levelMeterView;
 }
 
 - (IBAction)buttonPressed:(id)sender;

Classes/iPhoneStreamingPlayerViewController.m

@@ -15,6 +15,7 @@
 #import "iPhoneStreamingPlayerAppDelegate.h"
 #import "iPhoneStreamingPlayerViewController.h"
 #import "AudioStreamer.h"
+#import "LevelMeterView.h"
 #import <QuartzCore/CoreAnimation.h>
 #import <MediaPlayer/MediaPlayer.h>
 #import <CFNetwork/CFNetwork.h>
@@ -105,6 +106,11 @@ - (void)createStreamer
 			selector:@selector(updateProgress:)
 			userInfo:nil
 			repeats:YES];
+	levelMeterUpdateTimer = [NSTimer scheduledTimerWithTimeInterval:.1 
+															 target:self 
+														   selector:@selector(updateLevelMeters:) 
+														   userInfo:nil 
+															repeats:YES];
 	[[NSNotificationCenter defaultCenter]
 		addObserver:self
 		selector:@selector(playbackStateChanged:)
@@ -135,6 +141,9 @@ - (void)viewDidLoad
 	[volumeView sizeToFit];
 
 	[self setButtonImage:[UIImage imageNamed:@"playbutton.png"]];
+
+	levelMeterView = [[LevelMeterView alloc] initWithFrame:CGRectMake(10.0, 310.0, 300.0, 60.0)];
+	[self.view addSubview:levelMeterView];
 }
 
 - (void)viewDidAppear:(BOOL)animated {
@@ -256,14 +265,20 @@ - (void)playbackStateChanged:(NSNotification *)aNotification
 {
 	if ([streamer isWaiting])
 	{
+		[levelMeterView updateMeterWithLeftValue:0.0 
+									  rightValue:0.0];
+		[streamer setMeteringEnabled:NO];
 		[self setButtonImage:[UIImage imageNamed:@"loadingbutton.png"]];
 	}
 	else if ([streamer isPlaying])
 	{
+		[streamer setMeteringEnabled:YES];
 		[self setButtonImage:[UIImage imageNamed:@"stopbutton.png"]];
 	}
 	else if ([streamer isIdle])
 	{
+		[levelMeterView updateMeterWithLeftValue:0.0 
+									  rightValue:0.0];
 		[self destroyStreamer];
 		[self setButtonImage:[UIImage imageNamed:@"playbutton.png"]];
 	}
@@ -351,6 +366,20 @@ - (void)updateProgress:(NSTimer *)updatedTimer
 	}
 }
 
+
+//
+// updateLevelMeters:
+//
+
+- (void)updateLevelMeters:(NSTimer *)timer {
+	iPhoneStreamingPlayerAppDelegate *appDelegate = (iPhoneStreamingPlayerAppDelegate *)[[UIApplication sharedApplication] delegate];
+	if([streamer isMeteringEnabled] && appDelegate.uiIsVisible) {
+		[levelMeterView updateMeterWithLeftValue:[streamer averagePowerForChannel:0] 
+									  rightValue:[streamer averagePowerForChannel:1]];
+	}
+}
+
+
 //
 // textFieldShouldReturn:
 //
@@ -381,6 +410,11 @@ - (void)dealloc
 		[progressUpdateTimer invalidate];
 		progressUpdateTimer = nil;
 	}
+	if(levelMeterUpdateTimer) {
+		[levelMeterUpdateTimer invalidate];
+		levelMeterUpdateTimer = nil;
+	}
+	[levelMeterView release];
 	[super dealloc];
 }
 

iPhone Resources/iPhoneStreamingPlayerViewController.xib

@@ -136,7 +136,7 @@
 					<object class="IBUILabel" id="1000478862">
 						<reference key="NSNextResponder" ref="774585933"/>
 						<int key="NSvFlags">292</int>
-						<string key="NSFrame">{{20, 356}, {280, 21}}</string>
+						<string key="NSFrame">{{20, 376}, {280, 21}}</string>
 						<reference key="NSSuperview" ref="774585933"/>
 						<bool key="IBUIOpaque">NO</bool>
 						<bool key="IBUIClipsSubviews">YES</bool>
@@ -151,7 +151,7 @@
 					<object class="IBUIView" id="1067123130">
 						<reference key="NSNextResponder" ref="774585933"/>
 						<int key="NSvFlags">292</int>
-						<string key="NSFrame">{{20, 385}, {280, 55}}</string>
+						<string key="NSFrame">{{20, 405}, {280, 35}}</string>
 						<reference key="NSSuperview" ref="774585933"/>
 						<object class="NSColor" key="IBUIBackgroundColor">
 							<int key="NSColorSpace">3</int>
@@ -490,7 +490,7 @@
 					<string>com.apple.InterfaceBuilder.IBCocoaTouchPlugin</string>
 					<string>com.apple.InterfaceBuilder.IBCocoaTouchPlugin</string>
 					<string>com.apple.InterfaceBuilder.IBCocoaTouchPlugin</string>
-					<string>{{623, 248}, {320, 480}}</string>
+					<string>{{740, 290}, {320, 480}}</string>
 					<string>com.apple.InterfaceBuilder.IBCocoaTouchPlugin</string>
 				</object>
 			</object>

iPhoneStreamingPlayer.xcodeproj/project.pbxproj

@@ -13,6 +13,7 @@
 		1DF5F4E00D08C38300B7A737 /* UIKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 1DF5F4DF0D08C38300B7A737 /* UIKit.framework */; };
 		288765A50DF7441C002DB57D /* CoreGraphics.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 288765A40DF7441C002DB57D /* CoreGraphics.framework */; };
 		28D7ACF80DDB3853001CB0EB /* iPhoneStreamingPlayerViewController.m in Sources */ = {isa = PBXBuildFile; fileRef = 28D7ACF70DDB3853001CB0EB /* iPhoneStreamingPlayerViewController.m */; };
+		762375BF120E049F00518DB5 /* LevelMeterView.m in Sources */ = {isa = PBXBuildFile; fileRef = 762375BE120E049F00518DB5 /* LevelMeterView.m */; };
 		7646A326120C8F3C000ED48C /* UIDevice+Hardware.m in Sources */ = {isa = PBXBuildFile; fileRef = 7646A325120C8F3C000ED48C /* UIDevice+Hardware.m */; };
 		C9423DF10EF8AA6B003B785B /* CFNetwork.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C9423DF00EF8AA6B003B785B /* CFNetwork.framework */; };
 		C9AB93E20FCF816F0047C0FA /* AudioToolbox.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C9AB93E10FCF816F0047C0FA /* AudioToolbox.framework */; };
@@ -38,6 +39,8 @@
 		28D7ACF70DDB3853001CB0EB /* iPhoneStreamingPlayerViewController.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = iPhoneStreamingPlayerViewController.m; sourceTree = "<group>"; };
 		29B97316FDCFA39411CA2CEA /* main.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = main.m; sourceTree = "<group>"; };
 		32CA4F630368D1EE00C91783 /* iPhoneStreamingPlayer_Prefix.pch */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = iPhoneStreamingPlayer_Prefix.pch; sourceTree = "<group>"; };
+		762375BD120E049F00518DB5 /* LevelMeterView.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = LevelMeterView.h; sourceTree = "<group>"; };
+		762375BE120E049F00518DB5 /* LevelMeterView.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = LevelMeterView.m; sourceTree = "<group>"; };
 		7646A324120C8F3C000ED48C /* UIDevice+Hardware.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = "UIDevice+Hardware.h"; sourceTree = "<group>"; };
 		7646A325120C8F3C000ED48C /* UIDevice+Hardware.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = "UIDevice+Hardware.m"; sourceTree = "<group>"; };
 		C9423DF00EF8AA6B003B785B /* CFNetwork.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = CFNetwork.framework; path = System/Library/Frameworks/CFNetwork.framework; sourceTree = SDKROOT; };
@@ -77,12 +80,14 @@
 			isa = PBXGroup;
 			children = (
 				7646A321120C8F25000ED48C /* Additions */,
-				C9C2D8780EB6E09C00A3D071 /* AudioStreamer.m */,
 				C9C2D8790EB6E09C00A3D071 /* AudioStreamer.h */,
+				C9C2D8780EB6E09C00A3D071 /* AudioStreamer.m */,
 				1D3623240D0F684500981E51 /* iPhoneStreamingPlayerAppDelegate.h */,
 				1D3623250D0F684500981E51 /* iPhoneStreamingPlayerAppDelegate.m */,
 				28D7ACF60DDB3853001CB0EB /* iPhoneStreamingPlayerViewController.h */,
 				28D7ACF70DDB3853001CB0EB /* iPhoneStreamingPlayerViewController.m */,
+				762375BD120E049F00518DB5 /* LevelMeterView.h */,
+				762375BE120E049F00518DB5 /* LevelMeterView.m */,
 			);
 			path = Classes;
 			sourceTree = "<group>";
@@ -216,6 +221,7 @@
 				28D7ACF80DDB3853001CB0EB /* iPhoneStreamingPlayerViewController.m in Sources */,
 				C9C2D87A0EB6E09C00A3D071 /* AudioStreamer.m in Sources */,
 				7646A326120C8F3C000ED48C /* UIDevice+Hardware.m in Sources */,
+				762375BF120E049F00518DB5 /* LevelMeterView.m in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};