tumtumtum · tgrbin · Sep 10, 2014
diff --git a/ExampleApp/ExampleApp/AppDelegate.m b/ExampleApp/ExampleApp/AppDelegate.m
@@ -61,7 +61,7 @@ -(BOOL) canBecomeFirstResponder
 
 -(void) audioPlayerViewPlayFromHTTPSelected:(AudioPlayerView*)audioPlayerView
 {
-    NSURL* url = [NSURL URLWithString:@"file:///Users/tum/Temp/airplane-cut.aac"];
+    NSURL* url = [NSURL URLWithString:@"http://streaming.swisstxt.ch/m/rsj/mp3_128"];
 
     STKDataSource* dataSource = [STKAudioPlayer dataSourceFromURL:url];
 

diff --git a/ExampleApp/ExampleApp/AudioPlayerView.h b/ExampleApp/ExampleApp/AudioPlayerView.h
@@ -50,6 +50,7 @@
 	NSTimer* timer;
     UILabel* label;
     UILabel* statusLabel;
+    UILabel* metaDataLabel;
 	UISlider* slider;
     UISwitch* enableEqSwitch;
     UISwitch* repeatSwitch;

diff --git a/ExampleApp/ExampleApp/AudioPlayerView.m b/ExampleApp/ExampleApp/AudioPlayerView.m
@@ -111,9 +111,18 @@ - (id)initWithFrame:(CGRect)frame andAudioPlayer:(STKAudioPlayer*)audioPlayerIn
         label.textAlignment = NSTextAlignmentCenter;
 
         statusLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, slider.frame.origin.y + slider.frame.size.height + label.frame.size.height + 8, frame.size.width, 50)];
-
         statusLabel.textAlignment = NSTextAlignmentCenter;
-
+
+        metaDataLabel = [[UILabel alloc] initWithFrame:
+                         CGRectMake(
+                                    0,
+                                    statusLabel.frame.origin.y - 20,
+                                    frame.size.width,
+                                    15
+                                    )];
+        metaDataLabel.font = [UIFont systemFontOfSize:12];
+        metaDataLabel.textAlignment = NSTextAlignmentCenter;
+
 		meter = [[UIView alloc] initWithFrame:CGRectMake(0, 450, 0, 20)];
 
 		meter.backgroundColor = [UIColor greenColor];
@@ -127,6 +136,7 @@ - (id)initWithFrame:(CGRect)frame andAudioPlayer:(STKAudioPlayer*)audioPlayerIn
         [self addSubview:repeatSwitch];
         [self addSubview:label];
         [self addSubview:statusLabel];
+        [self addSubview:metaDataLabel];
         [self addSubview:stopButton];
 		[self addSubview:meter];
 		[self addSubview:muteButton];
@@ -353,4 +363,9 @@ -(void) audioPlayer:(STKAudioPlayer *)audioPlayer logInfo:(NSString *)line
     NSLog(@"%@", line);
 }
 
+-(void) audioPlayer:(STKAudioPlayer *)audioPlayer didUpdateMetaData:(NSDictionary *)metaData
+{
+    metaDataLabel.text = metaData[@"StreamTitle"];
+}
+
 @end
diff --git a/ExampleAppMac/ExampleAppMac/AppDelegate.m b/ExampleAppMac/ExampleAppMac/AppDelegate.m
@@ -13,6 +13,7 @@ @interface AppDelegate()
 {
 	NSView* meter;
 	NSSlider* slider;
+    NSTextField* metaDataTextField;
 	STKAudioPlayer* audioPlayer;
 }
 @end
@@ -36,9 +37,14 @@ -(void) applicationDidFinishLaunching:(NSNotification *)aNotification
 	[meter setWantsLayer:YES];
 	meter.layer.backgroundColor = [NSColor greenColor].CGColor;
 
+	metaDataTextField = [[NSTextField alloc] initWithFrame:CGRectMake(10, 270, frame.size.width - 20, 80)];
+	metaDataTextField.alignment = NSCenterTextAlignment;
+	metaDataTextField.stringValue = @"no meta data";
+
 	[[self.window contentView] addSubview:slider];
 	[[self.window contentView] addSubview:playFromHTTPButton];
 	[[self.window contentView] addSubview:meter];
+	[[self.window contentView] addSubview:metaDataTextField];
 
 	audioPlayer = [[STKAudioPlayer alloc] initWithOptions:(STKAudioPlayerOptions){ .enableVolumeMixer = NO, .equalizerBandFrequencies = {50, 100, 200, 400, 800, 1600, 2600, 16000} } ];
 	audioPlayer.delegate = self;
@@ -58,7 +64,8 @@ -(void) test
 
 -(void) playFromHTTP
 {
-	[audioPlayer play:@"http://www.abstractpath.com/files/audiosamples/sample.mp3"];
+    // Swiss Jazz stream
+	[audioPlayer play:@"http://streaming.swisstxt.ch/m/rsj/mp3_128"];
 }
 
 -(void) tick:(NSTimer*)timer
@@ -126,4 +133,9 @@ -(void) audioPlayer:(STKAudioPlayer*)audioPlayer unexpectedError:(STKAudioPlayer
 {
 }
 
+-(void) audioPlayer:(STKAudioPlayer *)audioPlayer didUpdateMetaData:(NSDictionary *)metaData
+{
+	metaDataTextField.stringValue = [metaData description];
+}
+
 @end
diff --git a/StreamingKit/StreamingKit/STKAudioPlayer.h b/StreamingKit/StreamingKit/STKAudioPlayer.h
@@ -129,6 +129,9 @@ typedef void(^STKFrameFilter)(UInt32 channelsPerFrame, UInt32 bytesPerFrame, UIn
 /// Raised when items queued items are cleared (usually because of a call to play, setDataSource or stop)
 -(void) audioPlayer:(STKAudioPlayer*)audioPlayer didCancelQueuedItems:(NSArray*)queuedItems;
 
+// Raised when new meta data arrives
+-(void)audioPlayer:(STKAudioPlayer *)audioPlayer didUpdateMetaData:(NSDictionary *)metaData;
+
 @end
 
 @interface STKAudioPlayer : NSObject<STKDataSourceDelegate>

diff --git a/StreamingKit/StreamingKit/STKAudioPlayer.m b/StreamingKit/StreamingKit/STKAudioPlayer.m
@@ -1611,6 +1611,13 @@ -(void) dataSourceEof:(STKDataSource*)dataSourceIn
     [self processRunloop];
 }
 
+-(void) dataSource:(STKDataSource *)dataSource didUpdateMetaData:(NSDictionary *)metaDataDictionary
+{
+    if ([self.delegate respondsToSelector:@selector(audioPlayer:didUpdateMetaData:)]) {
+        [self.delegate audioPlayer:self didUpdateMetaData:metaDataDictionary];
+    }
+}
+
 -(void) pause
 {
     pthread_mutex_lock(&playerMutex);

diff --git a/StreamingKit/StreamingKit/STKDataSource.h b/StreamingKit/StreamingKit/STKDataSource.h
@@ -41,6 +41,9 @@
 -(void) dataSourceDataAvailable:(STKDataSource*)dataSource;
 -(void) dataSourceErrorOccured:(STKDataSource*)dataSource;
 -(void) dataSourceEof:(STKDataSource*)dataSource;
+
+-(void) dataSource:(STKDataSource*)dataSource didUpdateMetaData:(NSDictionary *)metaDataDictionary;
+
 @end
 
 @interface STKDataSource : NSObject

diff --git a/StreamingKit/StreamingKit/STKDataSourceWrapper.m b/StreamingKit/StreamingKit/STKDataSourceWrapper.m
@@ -117,4 +117,9 @@ -(void) dataSourceEof:(STKDataSource*)dataSource
     [self.delegate dataSourceEof:self];
 }
 
+-(void) dataSource:(STKDataSource *)dataSource didUpdateMetaData:(NSDictionary *)metaDataDictionary
+{
+    [self.delegate dataSource:self didUpdateMetaData:metaDataDictionary];
+}
+
 @end
diff --git a/StreamingKit/StreamingKit/STKHTTPDataSource.m b/StreamingKit/StreamingKit/STKHTTPDataSource.m
@@ -50,6 +50,15 @@ @interface STKHTTPDataSource()
     NSDictionary* httpHeaders;
     AudioFileTypeID audioFileTypeHint;
     NSDictionary* requestHeaders;
+
+    // Meta data
+    BOOL metaDataPresent;
+    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
+    BOOL foundIcyStart;
+    BOOL foundIcyEnd;
+    NSMutableString *metaDataString;      //  meta data string
 }
 -(void) open;
 
@@ -90,6 +99,8 @@ -(id) initWithAsyncURLProvider:(STKAsyncURLProvider)asyncUrlProviderIn
         self->asyncUrlProvider = [asyncUrlProviderIn copy];
 
         audioFileTypeHint = [STKLocalFileDataSource audioFileTypeHintFromFileExtension:self->currentUrl.pathExtension];
+
+        metaDataString = [NSMutableString new];
     }
 
     return self;
@@ -267,6 +278,10 @@ -(int) readIntoBuffer:(UInt8*)buffer withSize:(int)size
         return read;
     }
 
+    // method will move audio bytes to the beginning of the buffer,
+    // and return their number
+    read = [self checkForMetaDataInfoWithBuffer:buffer andLength:read];
+
     relativePosition += read;
 
     return read;
@@ -313,6 +328,8 @@ -(void) openForSeek:(BOOL)forSeek
             CFHTTPMessageSetHeaderFieldValue(message, (__bridge CFStringRef)key, (__bridge CFStringRef)value);
         }
 
+        CFHTTPMessageSetHeaderFieldValue(message, CFSTR("Icy-MetaData"), CFSTR("1"));
+
         stream = CFReadStreamCreateForHTTPRequest(NULL, message);
 
         if (stream == nil)
@@ -394,4 +411,143 @@ -(NSString*) description
     return [NSString stringWithFormat:@"HTTP data source with file length: %lld and position: %lld", self.length, self.position];
 }
 
+#pragma mark - Meta data
+
+// This code was mostly taken from the link below
+// https://code.google.com/p/audiostreamer-meta/
+
+// Returns new length: the number of bytes from buffer that contain audio data.
+// Other bytes are meta data bytes and this method "consumes" them.
+-(int) checkForMetaDataInfoWithBuffer:(UInt8 *)buffer andLength:(int)length
+{
+    CFHTTPMessageRef response = (CFHTTPMessageRef)CFReadStreamCopyProperty(stream, kCFStreamPropertyHTTPResponseHeader);
+
+    if (foundIcyStart == NO && metaDataPresent == NO) {
+        // check if this is a ICY 200 OK response
+        NSString *icyCheck = [[NSString alloc] initWithBytes:buffer length:10 encoding:NSUTF8StringEncoding];
+        if (icyCheck != nil && [icyCheck caseInsensitiveCompare:@"ICY 200 OK"] == NSOrderedSame) {
+            foundIcyStart = YES;
+        } else {
+            NSString *metaInt = (__bridge NSString *) CFHTTPMessageCopyHeaderFieldValue(response, CFSTR("Icy-Metaint"));
+
+            if (metaInt) {
+                metaDataPresent = YES;
+                metaDataInterval = [metaInt intValue];
+            }
+        }
+    }
+
+    int streamStart = 0;
+
+    if (foundIcyStart == YES && foundIcyEnd == NO) {
+        char c[4] = {};
+
+        for (int lineStart = 0; streamStart + 3 < length; ++streamStart) {
+
+            memcpy(c, buffer + streamStart, 4);
+
+            if (c[0] == '\r' && c[1] == '\n') {
+                NSString *fullString = [[NSString alloc] initWithBytes:buffer length:streamStart encoding:NSUTF8StringEncoding];
+
+                NSString *line = [fullString substringWithRange:NSMakeRange(lineStart, streamStart - lineStart)];
+
+                NSArray *lineItems = [line componentsSeparatedByString:@":"];
+                if (lineItems.count > 1) {
+                    if ([lineItems[0] caseInsensitiveCompare:@"icy-metaint"] == NSOrderedSame) {
+                        metaDataInterval = [lineItems[1] intValue];
+                    } else if ([lineItems[0] caseInsensitiveCompare:@"content-type"] == NSOrderedSame) {
+                        AudioFileTypeID idFromMime = [STKHTTPDataSource audioFileTypeHintFromMimeType:lineItems[1]];
+                        if (idFromMime != 0) {
+                            audioFileTypeHint = idFromMime;
+                        }
+                    }
+                }
+
+                // this is the end of a line, the new line starts in 2
+                lineStart = streamStart + 2;
+
+                if (c[2] == '\r' && c[3] == '\n') {
+                    foundIcyEnd = YES;
+                    metaDataPresent = YES;
+                    streamStart += 4; // skip double new line
+                    break;
+                }
+            }
+        }
+    }
+
+    if (metaDataPresent == YES) {
+        int audioDataByteCount = 0;
+
+        for (int i = streamStart; i < length; ++i) {
+            // is this a metadata byte?
+            if (metaDataBytesRemaining > 0) {
+
+                [metaDataString appendFormat:@"%c", buffer[i]];
+
+                if (--metaDataBytesRemaining == 0) {
+                    dataBytesRead = 0;
+
+                    NSDictionary *metaDataDictionary = [self dictionaryFromMetaData:metaDataString];
+                    [self.delegate dataSource:self didUpdateMetaData:metaDataDictionary];
+                }
+
+                continue;
+            }
+
+            // is this the interval byte?
+            if (metaDataInterval > 0 && dataBytesRead == metaDataInterval) {
+
+                metaDataBytesRemaining = buffer[i] * 16;
+
+                metaDataString.string = @"";
+
+                if (metaDataBytesRemaining == 0) {
+                    dataBytesRead = 0;
+                }
+
+                continue;
+            }
+
+            // this is a data byte
+            ++dataBytesRead;
+
+            // overwrite beginning of the buffer with the real audio data
+            // we don't need those bytes any more, since we already examined them
+            buffer[audioDataByteCount++] = buffer[i];
+        }
+
+        return audioDataByteCount;
+
+    } else if (foundIcyStart == YES) { // still parsing icy response
+
+        return 0;
+
+    } else { // no meta data in stream
+
+        return length;
+
+    }
+}
+
+-(NSDictionary *) dictionaryFromMetaData:(NSString *)metaData
+{
+    NSArray *components = [metaData componentsSeparatedByString:@";"];
+
+    NSMutableDictionary *dictionary = [NSMutableDictionary new];
+
+    for (NSString *entry in components) {
+        NSInteger equalitySignPosition = [entry rangeOfString:@"="].location;
+        if (equalitySignPosition != NSNotFound) {
+            NSString *key = [entry substringToIndex:equalitySignPosition];
+            NSString *value = [entry substringFromIndex:equalitySignPosition + 1];
+            NSString *valueWithoutQuotes = [value substringWithRange:NSMakeRange(1, value.length - 2)];
+
+            dictionary[key] = valueWithoutQuotes;
+        }
+    }
+
+    return dictionary;
+}
+
 @end