DECODER.H

//==========================================================================; 
// 
//  THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY 
//  KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE 
//  IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR 
//  PURPOSE. 
// 
//  Copyright (c) 1992 - 1997  Microsoft Corporation.  All Rights Reserved. 
// 
//--------------------------------------------------------------------------; 
// 
/******************************Module*Header*******************************\ 
* Module Name: Decoder.h 
* 
* 
\**************************************************************************/ 
 
#ifndef _INC_DECODER_H 
#define _INC_DECODER_H 
 
 
// ------------------------------------------------------------------------- 
// Forward declaration to resolve circular reference. 
// ------------------------------------------------------------------------- 
// 
class CMpegAudioCodec; 
 
 
// ------------------------------------------------------------------------- 
// Audio decoder class 
// 
// This class encapsulates a low-level mpeg video decoder. 
// ------------------------------------------------------------------------- 
// 
 
// Decode control option 
enum { 
    DECODE_MONO       = 0x00000001L, 
    DECODE_STEREO     = 0x00000002L, 
    DECODE_QUARTER    = 0x00000800L, 
    DECODE_HALF       = 0x00001000L, 
    DECODE_FULL       = 0x00002000L, 
    DECODE_HALF_HIQ   = 0x00004000L, 
    DECODE_HALF_FULLQ = 0x00008000L, 
    DECODE_16BIT      = 0x00010000L, 
    DECODE_8BIT       = 0x00020000L, 
    DECODE_QSOUND     = 0x00040000L, 
    DECODE_QUART_INT  = 0x00080000L 
}; 
 
 
 
// Function Return Values 
enum { 
    DECODE_SUCCESS    = 0x0000L, 
    DECODE_ERR_MEMORY = 0x0001L, 
    DECODE_ERR_DATA   = 0x0002L, 
    DECODE_ERR_PARAM  = 0x0004L, 
    DECODE_ERR_QUARTZ = 0x0008L     // error from Quartz callback 
}; 
 
struct AudioCtrl { 
 
    // 
    // Output Frame Buffer 
    // 
    DWORD   dwOutBuffUsed; 
    DWORD   dwOutBuffSize; 
    DWORD   dwMpegError; 
 
    // 
    // Frame decoder control 
    // 
    DWORD   dwCtrl; 
 
 
    // 
    // Input buffer fields 
    // 
    DWORD   dwNumFrames; 
    LPBYTE  pCmprRead; 
    LPBYTE  pCmprWrite; 
    LPBYTE  pOutBuffer; 
}; 
 
 
class CAudioDecoder 
    : public CCritSec { 
 
private: 
    // 
    // Back pointer to the object that created us. 
    // 
    CMpegAudioCodec *m_pCodec; 
    AudioCtrl       *m_pCtrl; 
 
    BOOL    SkipFrame(); 
 
public: 
    CAudioDecoder(CMpegAudioCodec *pMpegCodec); 
 
    DWORD   ResetAudio(); 
    DWORD   DecodeAudioFrame(AudioCtrl *pCtrl); 
}; 
#endif