--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mmlibs/mmfw/Recogniser/src/id3parser.cpp	Thu Oct 07 22:34:12 2010 +0100
@@ -0,0 +1,93 @@
+// Copyright (c) 2006-2009 Nokia Corporation and/or its subsidiary(-ies).
+// All rights reserved.
+// This component and the accompanying materials are made available
+// under the terms of "Eclipse Public License v1.0"
+// which accompanies this distribution, and is available
+// at the URL "http://www.eclipse.org/legal/epl-v10.html".
+//
+// Initial Contributors:
+// Nokia Corporation - initial contribution.
+//
+// Contributors:
+//
+// Description:
+//
+
+#include "parsers.h"
+
+// The ID3 tag has a 10 byte header.
+static const TInt KID3HeaderSize = 10;
+
+
+//
+// Checks if an ID3 header is present at the current
+// reader position, and skips over it if it is.
+// Returns ETrue if a header was found, EFalse otherwise.
+//
+TBool TID3Parser::ReadAndSkipID3L(CReader& aReader)
+	{
+	TBuf8<KID3HeaderSize> header;
+	TUint8 a;
+	TUint8 b;
+	TUint8 c;
+	TUint8 d;
+	
+	header.SetLength(KID3HeaderSize);
+	aReader.ReadBytesL(header);
+	
+	do
+		{
+		// Look for the ID3 header.
+		if ((header[0] != 'I') || (header[1] != 'D') || (header[2] != '3'))
+			{
+			break;
+			}
+			
+		// The last 4 bits of byte[5] should be zero.
+		if ((header[5] & 0x0f))	// [00001111]
+			{
+			break;
+			}
+			
+		// Read the tag size. It's stored in a sync-safe manner
+		// (the highest bit is never set so it won't be confused
+		// with a frame-sync). If the highest bit is set, it's invalid.
+		a = header[6];
+		b = header[7];
+		c = header[8];
+		d = header[9];
+		
+		// OR the values together and check that the highest bit of
+		// the result isn't set. Saves on doing four individual checks.
+		if ((a | b | c | d) & 0x80) // [10000000]
+			{
+			break;
+			}
+		
+		// Convert from sync-safe format to normal format.
+		// [0aaaaaaa][0bbbbbbb][0ccccccc][0ddddddd] is changed to
+		// [0000aaaa][aaabbbbb][bbcccccc][cddddddd]
+		//
+		// Copy bit[0] of c into bit[7] of d.
+		d |= ((c & 0x01) << 7);
+		c >>= 1;
+		
+		// Copy bit[1,0] of b into bit[7,6] of c.
+		c |= ((b & 0x03) << 6);
+		b >>= 2;
+		
+		// Copy bit[2,1,0] of a into bit[7,6,5] of b.
+		b |= ((a & 0x07) << 5);
+		a >>= 3;
+		
+		TInt length = MAKE_INT32(a, b, c, d);
+		aReader.SeekL(length);
+		return ETrue;
+		}
+	while (EFalse);
+	
+	// It's not an ID3 header.
+	// Undo the header read.
+	aReader.SeekL(-KID3HeaderSize);
+	return EFalse;
+	}