1

engine/audio/private/VBRHeader.h

@@ -0,0 +1,72 @@
+//========= Copyright Valve Corporation, All rights reserved. ============//
+//
+// Purpose: 
+//
+//=============================================================================
+
+#ifndef VBRHEADER_H
+#define VBRHEADER_H
+#ifdef _WIN32
+#pragma once
+#endif
+
+// for XING VBR Header flags
+#define FRAMES_FLAG     0x0001
+#define BYTES_FLAG      0x0002
+#define TOC_FLAG        0x0004
+#define VBR_SCALE_FLAG  0x0008
+
+class CMPAFile;
+
+class CVBRHeader
+{
+public:
+	enum VBRHeaderType
+	{
+		NoHeader,
+		XINGHeader,
+		VBRIHeader
+	};
+
+	CVBRHeader( CMPAFile* pMPAFile, VBRHeaderType HeaderType, uint32 dwOffset );
+	~CVBRHeader(void);
+
+	static bool IsVBRHeaderAvailable( CMPAFile* pMPAFile, VBRHeaderType& HeaderType, uint32& dwOffset );
+	bool SeekPoint(float fPercent, uint32& dwSeekPoint);
+
+	uint32 m_dwBytesPerSec;
+	uint32 m_dwBytes;		// total number of bytes
+	uint32 m_dwFrames;		// total number of frames
+
+private:
+	static uint32 m_dwXINGOffsets[2][2];
+
+	static bool CheckID( CMPAFile* pMPAFile, char ch0, char ch1, char ch2, char ch3, uint32& dwOffset );
+	static bool CheckXING( CMPAFile* pMPAFile, uint32& dwOffset );
+	static bool CheckVBRI( CMPAFile* pMPAFile, uint32& dwOffset );
+
+	bool ExtractLAMETag( uint32 dwOffset );
+	bool ExtractXINGHeader( uint32 dwOffset );	
+	bool ExtractVBRIHeader( uint32 dwOffset );
+
+	uint32 SeekPointXING(float fPercent)const ;
+	uint32 SeekPointVBRI(float fPercent) const;
+	uint32 SeekPointByTimeVBRI(float fEntryTimeMS) const;
+
+	CMPAFile* m_pMPAFile;
+public:	
+	VBRHeaderType m_HeaderType;
+	uint32 m_dwOffset;
+	uint32 m_dwQuality;	// quality (0..100)
+	int* m_pnToc;				// TOC points for seeking (must be freed)
+	uint32 m_dwTableSize;	// size of table (number of entries)	
+
+	// only VBRI
+	float m_fDelay;	
+	uint32 m_dwTableScale;	// for seeking
+	uint32 m_dwBytesPerEntry;
+    uint32 m_dwFramesPerEntry;
+	uint32 m_dwVersion;
+};
+
+#endif // VBRHEADER_H