sl@0: // Copyright (c) 2006-2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0: // All rights reserved.
sl@0: // This component and the accompanying materials are made available
sl@0: // under the terms of "Eclipse Public License v1.0"
sl@0: // which accompanies this distribution, and is available
sl@0: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: //
sl@0: // Initial Contributors:
sl@0: // Nokia Corporation - initial contribution.
sl@0: //
sl@0: // Contributors:
sl@0: //
sl@0: // Description:
sl@0: //
sl@0: 
sl@0: #include "constants.h"
sl@0: #include "parsers.h"
sl@0: 
sl@0: #define KASFAudioMedia				"\xF8\x69\x9E\x40\x5B\x4D\x11\xCF\xA8\xFD\x00\x80\x5F\x5C\x44\x2B"
sl@0: #define KASFVideoMedia				"\xBC\x19\xEF\xC0\x5B\x4D\x11\xCF\xA8\xFD\x00\x80\x5F\x5C\x44\x2B"
sl@0: #define KASFHeaderObject 			"\x75\xB2\x26\x30\x66\x8E\x11\xCF\xA6\xD9\x00\xAA\x00\x62\xCE\x6C"
sl@0: #define KASFStreamPropertiesObject	"\xB7\xDC\x07\x91\xA9\xB7\x11\xCF\x8E\xE6\x00\xC0\x0C\x20\x53\x65"
sl@0: #define KASFCodecListObject			"\x86\xD1\x52\x40\x31\x1D\x11\xD0\xA3\xA4\x00\xA0\xC9\x03\x48\xF6"
sl@0: 
sl@0: 
sl@0: static const TInt KGUIDLen = 16; 				// 128-bit
sl@0: static const TInt KObjectLen = KGUIDLen + 8; 	// GUID followed by 64-bit size.
sl@0: static const TInt KMinObjectLen = 30; 			// From documentation
sl@0: 
sl@0: 
sl@0: typedef struct
sl@0: 	{
sl@0: 	const TText* iExt;
sl@0: 	const TText8* iVideoMime;
sl@0: 	const TText8* iAudioMime;
sl@0: 	}
sl@0: TASFType;
sl@0: 
sl@0: 
sl@0: //
sl@0: // Various ASF container MIME-types.
sl@0: //
sl@0: static const TASFType KASFTypes[] =
sl@0: 	{
sl@0: 		{KExtWMA,	KMimeWMA,	KMimeWMA},
sl@0: 		{KExtWMV,	KMimeWMV,	KMimeWMV},
sl@0: 		{KExtASF,	KMimeASF_V,	KMimeASF_A}
sl@0: 	};
sl@0: 
sl@0: #define KASFTypesCount	sizeof(KASFTypes) / sizeof(TASFType)
sl@0: 
sl@0: 
sl@0: #define KASFHeaderObjectBit		KBit1	// 00000001
sl@0: #define KASFStreamHeaderBit		KBit2	// 00000010
sl@0: #define KASFVideoBit			KBit3	// 00000100
sl@0: #define KASFConfidenceMask		0x07	// 00000111
sl@0: 
sl@0: //
sl@0: // Flags mapped to confidence levels.
sl@0: //
sl@0: // A: Extension identified.
sl@0: // B: HeaderObject GUID
sl@0: // C: StreamProperties GUID
sl@0: //
sl@0: // C B A -> Confidence
sl@0: // -------------------
sl@0: // 0 0 0 -> ENotRecognised
sl@0: // 0 0 1 -> EPossible
sl@0: // 0 1 0 -> EPossible
sl@0: // 0 1 1 -> EProbable
sl@0: // 1 0 0 -> ENotRecognised (StreamProperties occurs within HeaderObject)
sl@0: // 1 0 1 -> ENotRecognised (StreamProperties occurs within HeaderObject)
sl@0: // 1 1 0 -> EProbable
sl@0: // 1 1 1 -> ECertain
sl@0: //
sl@0: static const TInt KASFFlagsToConfidence[8] = 
sl@0: 	{
sl@0: 	KConfNotRecognised,
sl@0: 	KConfPossible,
sl@0: 	KConfPossible,
sl@0: 	KConfProbable,
sl@0: 	KConfNotRecognised,
sl@0: 	KConfNotRecognised,
sl@0: 	KConfProbable,
sl@0: 	KConfCertain
sl@0: 	};
sl@0: 
sl@0: 
sl@0: //
sl@0: //
sl@0: //
sl@0: TASFParser::TASFParser(CReader& aReader, TFlags& aFlags)
sl@0:  :	iReader(aReader),
sl@0:  	iFlags(aFlags)
sl@0: 	{
sl@0: 	}
sl@0: 
sl@0: 
sl@0: //
sl@0: // Sets the mime-type the file extension implies.
sl@0: //
sl@0: const TText8* TASFParser::MatchExtension(const TDesC& aExt, TBool aVideo)
sl@0: 	{
sl@0: 	for (TInt i = 0; i < KASFTypesCount; i++)
sl@0: 		{
sl@0: 		if (aExt.MatchF(TPtrC(KASFTypes[i].iExt)) != KErrNotFound)
sl@0: 			{
sl@0: 			return (aVideo ? KASFTypes[i].iVideoMime : KASFTypes[i].iAudioMime);
sl@0: 			}
sl@0: 		}
sl@0: 		
sl@0: 	return NULL;
sl@0: 	}
sl@0: 
sl@0: 
sl@0: //
sl@0: //
sl@0: //
sl@0: void TASFParser::DoRecognise(const TDesC& aExt, CReader& aReader, TMatch& aMatch)
sl@0: 	{
sl@0: 	TFlags flags;
sl@0: 	TASFParser parser(aReader, flags);
sl@0: 	
sl@0: 	// We need to parse first to determine if there's video content present.
sl@0: 	TRAPD(err, parser.ParseL());
sl@0: 	if (err == KErrCorrupt)
sl@0: 		{
sl@0: 		// Unrecognised content. However the extension may allow
sl@0: 		// correct identification so assume there's video content.
sl@0: 		flags.SetBit(KASFVideoBit);
sl@0: 		}
sl@0: 		
sl@0: 	const TText8* extMime = parser.MatchExtension(aExt, flags.GetBitField(KASFVideoBit));
sl@0: 	if (extMime != NULL)
sl@0: 		{
sl@0: 		// The extension was recognised.
sl@0: 		flags.SetExtensionFlag();
sl@0: 		}
sl@0: 		
sl@0: 	TInt confIndex = flags.GetBitField(KASFConfidenceMask);
sl@0: 	aMatch.iConfidence = KASFFlagsToConfidence[confIndex];
sl@0: 	if (aMatch.iConfidence != KConfNotRecognised)
sl@0: 		{
sl@0: 		// Trust the mime-type the extension maps to.
sl@0: 		// If the extension wasn't recognised, but the content was
sl@0: 		// then return the generic ASF mime type. ASF format files
sl@0: 		// can't be identified from their content; just whether they
sl@0: 		// contain video or not.
sl@0: 		aMatch.iMime = extMime;
sl@0: 		if (aMatch.iMime == NULL)
sl@0: 			{
sl@0: 			aMatch.iMime = (flags.GetBitField(KASFVideoBit) ? KMimeASF_V : KMimeASF_A);
sl@0: 			}
sl@0: 		}
sl@0: 	}
sl@0: 
sl@0: 
sl@0: //
sl@0: //
sl@0: //
sl@0: void TASFParser::ParseL()
sl@0: 	{
sl@0: 	// ASF files are logically composed of three types of top-level objects:
sl@0: 	// the Header Object, the Data Object, and the Index Object(s).
sl@0: 	// The Header Object is mandatory and must be placed at the beginning of every
sl@0: 	// ASF file. The Data Object is also mandatory and must follow the Header Object.
sl@0: 	// The Index Object(s) are optional, but they are useful in providing time-based
sl@0: 	// random access into ASF files. When present, the Index Object(s) must be the
sl@0: 	// last object in the ASF file. 
sl@0: 	
sl@0: 	TBuf8<KGUIDLen> guid;
sl@0: 	TInt64 size;
sl@0: 	const TBool useLittleEndian = ETrue;
sl@0: 	
sl@0: 	// Assume there's video content present if we only have buffer data.
sl@0: 	if (iReader.Type() == CReader::EBuffer)
sl@0: 		{
sl@0: 		iFlags.SetBit(KASFVideoBit);
sl@0: 		}
sl@0: 		
sl@0: 	ReadObjectL(guid, size);
sl@0: 	if (guid == MAKE_TPtrC8(KASFHeaderObject))
sl@0: 		{
sl@0: 		TUint32 objectCount;
sl@0: 		
sl@0: 		if (size < KMinObjectLen)
sl@0: 			{
sl@0: 			User::Leave(KErrCorrupt);
sl@0: 			}
sl@0: 			
sl@0: 		iFlags.SetBit(KASFHeaderObjectBit);
sl@0: 		// We need to find out how many objects there are.
sl@0: 		iReader.Read32L(objectCount, useLittleEndian);
sl@0: 		iReader.SeekL(2); // Ignore reserved values (two bytes).
sl@0: 		
sl@0: 		const TDesC8& streamPropertiesGUID = MAKE_TPtrC8(KASFStreamPropertiesObject);
sl@0: 		const TDesC8& videoMediaGUID = MAKE_TPtrC8(KASFVideoMedia);
sl@0: 		
sl@0: 		for (TInt i = 0; i < objectCount; i++)
sl@0: 			{
sl@0: 			ReadObjectL(guid, size);
sl@0: 			
sl@0: 			// We want the stream properties object.
sl@0: 			if (guid == streamPropertiesGUID)
sl@0: 				{
sl@0: 				// There may be more than one present.
sl@0: 				iFlags.SetBit(KASFStreamHeaderBit);
sl@0: 				
sl@0: 				ReadGUIDL(guid);
sl@0: 				if (guid == videoMediaGUID)
sl@0: 					{
sl@0: 					iFlags.SetBit(KASFVideoBit);
sl@0: 					}
sl@0: 				iReader.SeekL(size - KObjectLen - KGUIDLen);
sl@0: 				}
sl@0: 			else
sl@0: 				{
sl@0: 				iReader.SeekL(size - KObjectLen);
sl@0: 				}
sl@0: 			}
sl@0: 		}
sl@0: 	else
sl@0: 		{
sl@0: 		User::Leave(KErrCorrupt);
sl@0: 		}
sl@0: 	}
sl@0: 	
sl@0: //
sl@0: //
sl@0: //
sl@0: void TASFParser::ReadObjectL(TDes8& aGUID, TInt64& aSize)
sl@0: 	{
sl@0: 	//The base unit of organization for ASF files is called the ASF object.
sl@0: 	//It consists of a 128-bit GUID for the object, a 64-bit integer object size,
sl@0: 	//and the variable-length object data. The value of the object size field is
sl@0: 	//the sum of 24 bytes plus the size of the object data in bytes.
sl@0: 	
sl@0: 	TUint32 word1;
sl@0: 	TUint32 word2;
sl@0: 	const TBool useLittleEndian = ETrue;
sl@0: 	
sl@0: 	aGUID.SetLength(KGUIDLen);
sl@0: 	ReadGUIDL(aGUID);
sl@0: 	
sl@0: 	iReader.Read32L(word2, useLittleEndian);
sl@0: 	iReader.Read32L(word1, useLittleEndian);
sl@0: 	
sl@0: 	aSize = MAKE_TINT64(word1, word2);
sl@0: 	}
sl@0: 
sl@0: 
sl@0: //
sl@0: //
sl@0: //
sl@0: void TASFParser::ReadGUIDL(TDes8& aGUID)
sl@0: 	{
sl@0: 	TUint8 byte;
sl@0: 	
sl@0: 	if (aGUID.Length() != KGUIDLen)
sl@0: 		{
sl@0: 		User::Leave(KErrUnderflow);
sl@0: 		}
sl@0: 	
sl@0: 	// Parts of the GUID are stored in big-endian order.
sl@0: 	// They're converted to little-endian order here.
sl@0: 	iReader.ReadByteL(byte);	aGUID[3] = byte;
sl@0: 	iReader.ReadByteL(byte);	aGUID[2] = byte;
sl@0: 	iReader.ReadByteL(byte);	aGUID[1] = byte;
sl@0: 	iReader.ReadByteL(byte);	aGUID[0] = byte;
sl@0: 	
sl@0: 	iReader.ReadByteL(byte);	aGUID[5] = byte;
sl@0: 	iReader.ReadByteL(byte);	aGUID[4] = byte;
sl@0: 	
sl@0: 	iReader.ReadByteL(byte);	aGUID[7] = byte;
sl@0: 	iReader.ReadByteL(byte);	aGUID[6] = byte;
sl@0: 	
sl@0: 	for (TInt i = 8; i < KGUIDLen; i++)
sl@0: 		{
sl@0: 		iReader.ReadByteL(byte);
sl@0: 		aGUID[i] = byte; 
sl@0: 		}
sl@0: 	}
sl@0: