www.pudn.com > RSImageManger.rar > PICDEC.H
/*
/--------------------------------------------------------------------
|
| $Id: picdec.h,v 1.7 2000/03/30 21:24:15 Ulrich von Zadow Exp $
|
| Copyright (c) 1996-1998 Ulrich von Zadow
|
\--------------------------------------------------------------------
*/
#ifndef INCL_PICDEC
#define INCL_PICDEC
#ifndef INCL_BITMAP
#include "bitmap.h"
#endif
#ifndef INCL_DATASRC
#include "datasrc.h"
#endif
//! CPicDecoder is an abstract base class. It defines common routines
//! for all decoders. Decoders for specific file formats can be
//! derived from this class. Objects of this class interact with a
//! CDataSource to decode bitmaps.
class CPicDecoder : public CPLObject
{
public:
//! Empty constructor. The actual initialization takes place in a
//! derived class.
CPicDecoder
();
//! Destructor. Frees memory allocated.
virtual ~CPicDecoder
();
//! Decodes a picture in a file and stores the results in pBmp.
//! BPPWanted is the number of bits per pixel in the bitmap
//! returned. Valid values for BPPWanted are 8, 24, and 0.
//! 0 means 'keep the input format'. Decoding a true-color image
//! to 8 bpp is not supported. As an exception, BPPWanted can be
//! 1 for b/w tiff files.
virtual void MakeBmpFromFile
( const char * pszFName,
CBmp * pBmp,
int BPPWanted = 0,
IProgressNotification * pProgNot = NULL
);
#ifdef _WINDOWS
//! Decodes a picture in a resource by creating a resource data
//! source and calling MakeBmp with this data source.
//! BPPWanted is the number of bits per pixel in the bitmap
//! returned. Valid values for BPPWanted are 8, 24, and 0.
//! 0 means 'keep the input format'. Decoding a true-color image
//! to 8 bpp is not supported. As an exception, BPPWanted can be
//! 1 for b/w tiff files.
//! ResType is the windows resource type (e.g. "JPEG") to be used.
//!
//! New optional parameter: hResModule (04.01.2000 ms)
//! If a module handle is passed as hResModule, then the resource
//! will be loaded from this module, otherwise, the resource
//! will be searched for by AfxFindResourceHandle (! MFC dependent!)
void MakeBmpFromResource
( HINSTANCE hInstResource, int ResourceID,
CBmp * pBmp,
int BPPWanted = 0,
const char* ResType = NULL,
HMODULE hResModule = 0
);
#endif
//! Decodes a picture from a memory location which directly resembles
//! the image file as it would be on disc. The result is stored in pBmp.
//! BPPWanted is the number of bits per pixel in the bitmap
//! returned. Valid values for BPPWanted are 8, 24, and 0.
//! 0 means 'keep the input format'. Decoding a true-color image
//! to 8 bpp is not supported. As an exception, BPPWanted can be
//! 1 for b/w tiff files.
virtual void CPicDecoder::MakeBmpFromMemory
( unsigned char * ucMemSrc,
int MemSrcSize,
CBmp * pBmp,
int BPPWanted = 0,
IProgressNotification * pProgNot = NULL
);
//! Decodes a picture by getting the encoded data from pDataSrc.
//! Stores the results in pBmp. BPPWanted is the number of bits
//! per pixel in the bitmap returned. Valid values for BPPWanted
//! are 8, 24, and 0. 0 means 'keep the input format'. Decoding a
//! true-color image to 8 bpp is not supported.
virtual void MakeBmp
( CDataSource * pDataSrc,
CBmp * pBmp,
int BPPWanted = 0
);
//! Sets the amount and destination of debug traces output by the
//! debug version. pszFName contains either a valid file name or is
//! NULL. If it contains a file name, this file is used to store
//! debug information. If pszFName is NULL, the destination is
//! either the MSVC debug console or stderr depending on the
//! version of the library. Valid values for Level are:
//!
//! 0: Trace only errors.
//! 1: Trace top-level calls.
//! 2: Trace picture format information
//! 3: Trace all miscellaneous info.
//!
//! The trace configuration is global to all decoders.
static void SetTraceConfig
( int Level,
char * pszFName
);
// This function is needed by callbacks outside of any object,
// so it's public and static. It should not be called from
// outside of the library.
static void raiseError
( int Code,
char * pszErr
);
//! Called to output status messages to the current debug console
static void Trace
( int TraceLevel,
const char * pszMessage
);
protected:
//! Implements the actual decoding process. Uses variables local to
//! the object to retrieve and store the data. Implemented in
//! derived classes.
//!
//! This routine should never be called. It's here so derived classes
//! can override MakeDIB directly if they want to. (CAnyDecoder does
//! this).
virtual void DoDecode
( CBmp * pBmp,
RGBAPIXEL ** ppPal,
int * pDestBPP,
CDataSource * pDataSrc
);
// These routines expand pixel data of various bit depths to 32 bpp.
// The original intent was for several derived classes to use them.
// As it is, they are too slow & therefore almost unused.
void Expand1bpp
( BYTE * pDest,
BYTE * pSrc,
int Width, // Width in pixels
RGBAPIXEL * pPal
);
void Expand2bpp
( BYTE * pDest,
BYTE * pSrc,
int Width, // Width in pixels
RGBAPIXEL * pPal
);
void Expand4bpp
( BYTE * pDest,
BYTE * pSrc,
int Width, // Width in pixels
RGBAPIXEL * pPal
);
void Expand8bpp
( BYTE * pDest,
BYTE * pSrc,
int Width, // Width in pixels
RGBAPIXEL * pPal
);
BYTE ReadByte
( CDataSource * pDataSrc
);
// Machine-independent routines for byte-order conversion.
WORD ReadIWord
( CDataSource * pDataSrc
);
WORD ReadMWord
( CDataSource * pDataSrc
);
LONG ReadILong
( CDataSource * pDataSrc
);
LONG ReadMLong
( CDataSource * pDataSrc
);
void CalcDestBPP
( int SrcBPP,
int* DestBPP
);
private:
///////////////////////////////////////////////////////////////////
// Member variables.
static int m_TraceLevel; // 0: Trace only errors.
// 1: Trace top-level calls.
// 2: Trace picture format info.
// 3: Trace misc. info.
static char * m_pszTraceFName; // Name of trace file. NULL if trace to
// MSVC debug console.
};
inline BYTE CPicDecoder::ReadByte
( CDataSource * pDataSrc
)
{
return *(pDataSrc->ReadNBytes (1));
}
inline WORD CPicDecoder::ReadIWord
( CDataSource * pDataSrc
)
{
BYTE * pData = pDataSrc->Read2Bytes ();
// This should work regardless of the destination byte order ;-)
return pData[0] + (pData[1]<<8);
}
inline WORD CPicDecoder::ReadMWord
( CDataSource * pDataSrc
)
{
BYTE * pData = pDataSrc->Read2Bytes ();
return pData[1] + (pData[0]<<8);
}
inline LONG CPicDecoder::ReadILong
( CDataSource * pDataSrc
)
{
BYTE * pData = pDataSrc->Read4Bytes ();
return pData[0] + (pData[1]<<8) + (pData[2]<<16) + (pData[3]<<24);
}
inline LONG CPicDecoder::ReadMLong
( CDataSource * pDataSrc
)
{
BYTE * pData = pDataSrc->Read4Bytes ();
return pData[3] + (pData[2]<<8) + (pData[1]<<16) + (pData[0]<<24);
}
#endif
/*
/--------------------------------------------------------------------
|
| $Log: picdec.h,v $
| Revision 1.7 2000/03/30 21:24:15 Ulrich von Zadow
| Added MakeBmpFromMemory() function by Markus Ewald
|
| Revision 1.6 2000/01/16 20:43:14 anonymous
| Removed MFC dependencies
|
| Revision 1.5 2000/01/11 21:40:30 Ulrich von Zadow
| Added instance handle parameter to LoadFromResource()
|
| Revision 1.4 2000/01/08 15:51:30 Ulrich von Zadow
| Misc. modifications to png encoder.
|
| Revision 1.3 1999/11/08 22:12:51 Ulrich von Zadow
| Andreas Koepf: Added resource type as parameter to
| MakeBmpFromResource
|
|
\--------------------------------------------------------------------
*/