plpicdec.h

/*
/--------------------------------------------------------------------
|
|      $Id: plpicdec.h,v 1.10 2003/08/03 12:54:10 uzadow Exp $
|
|      Copyright (c) 1996-2002 Ulrich von Zadow
|
\--------------------------------------------------------------------
*/

#ifndef INCL_PLPICDEC
#define INCL_PLPICDEC

#ifndef INCL_PLBITMAP
#include "plbitmap.h"
#endif

#ifndef INCL_PLDATASRC
#include "pldatasrc.h"
#endif

//! PLPicDecoder 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
//! PLDataSource to decode bitmaps.
class PLPicDecoder : public PLBmpInfo
{

public:
  //! Empty constructor. The actual initialization takes place in a
  //! derived class.
  PLPicDecoder
    ();

  //! Destructor. Frees memory allocated.
  virtual ~PLPicDecoder
    ();

  //! 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,
      PLBmp * pBmp,
      int BPPWanted = 0,
      PLIProgressNotification * pProgNot = NULL
    );

#ifdef _WINDOWS  
  //! Decodes a picture in a file and stores the results in pBmp.
  //! Wide-Character version (windows only). 
  virtual void MakeBmpFromFileW
    ( const wchar_t * pszwFName,
      PLBmp * pBmp,
      int BPPWanted = 0,
      PLIProgressNotification * pProgNot = NULL
    );
#endif


  //! 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 MakeBmpFromURL
    ( const char * pszURL,
      PLBmp * pBmp,
      int BPPWanted = 0,
      PLIProgressNotification * pProgNot = NULL
    );

#ifdef _WINDOWS
  //! Decodes a picture in a windows 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.
  //! 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!)
  virtual void MakeBmpFromResource
    ( HINSTANCE hInstResource, int ResourceID,
      PLBmp * 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 MakeBmpFromMemory
    ( unsigned char * ucMemSrc,
      int MemSrcSize,
      PLBmp * pBmp,
      int BPPWanted = 0,
      PLIProgressNotification * pProgNot = NULL
    );

#ifdef _WINDOWS
  void OpenFileW
    ( const wchar_t * pszwFName, 
      PLIProgressNotification * pProgNot = NULL
    );
#endif
  //! 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
    ( PLBmp * pBmp,
      int BPPWanted = 0
    );

  //! Decodes a picture by getting the encoded data from pDataSrc.
  //! Open should be called before, close after this routine is called.
  void OpenFile
    ( const char * pszFName, 
      PLIProgressNotification * pProgNot = NULL
    );
  
  //!
  virtual void Close
    ();

  //! 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: <BR>
  //! <BR>
  //! 0: Trace only errors.<BR>
  //! 1: Trace top-level calls.<BR>
  //! 2: Trace picture format information<BR>
  //! 3: Trace all miscellaneous info.<BR>
  //! <BR>
  //! The trace configuration is global to all decoders.
  static void SetTraceConfig
    ( int Level,
      char * pszFName
    );

  //!
  virtual void Open (PLDataSource * pDataSrc)=0;

  //!
  virtual void GetImage (PLBmp & Bmp) = 0;

  // Used only by PLAnyPicDecoder
  void SetDataSrc (PLDataSource * pDataSrc);

  // 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:
  // TODO: What is this doing here?!
  PLBYTE * unpackPictRow
    ( PLBYTE * pLineBuf,
      PLDataSource * pDataSrc,
      int Width,
      int rowBytes,
      int SrcBytes
    );

  PLBYTE ReadByte
    ( PLDataSource * pDataSrc
    );

  // Machine-independent routines for byte-order conversion.

  PLWORD ReadIWord
    ( PLDataSource * pDataSrc
    );

  PLWORD ReadMWord
    ( PLDataSource * pDataSrc
    );

  PLLONG ReadILong
    ( PLDataSource * pDataSrc
    );

  PLLONG ReadMLong
    ( PLDataSource * pDataSrc
    );

  PLDataSource * m_pDataSrc;

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 PLBYTE PLPicDecoder::ReadByte
    ( PLDataSource * pDataSrc
    )
{

  return *(pDataSrc->ReadNBytes (1));
}


inline PLWORD PLPicDecoder::ReadIWord
    ( PLDataSource * pDataSrc
    )
{
  PLBYTE * pData = pDataSrc->Read2Bytes ();
  // This should work regardless of the destination byte order ;-)
  return pData[0] + (pData[1]<<8);
}


inline PLWORD PLPicDecoder::ReadMWord
    ( PLDataSource * pDataSrc
    )
{
  PLBYTE * pData = pDataSrc->Read2Bytes ();
  return pData[1] + (pData[0]<<8);
}


inline PLLONG PLPicDecoder::ReadILong
    ( PLDataSource * pDataSrc
    )
{
  PLBYTE * pData = pDataSrc->Read4Bytes ();
  return pData[0] + (pData[1]<<8) + (pData[2]<<16) + (pData[3]<<24);
}

inline PLLONG PLPicDecoder::ReadMLong
    ( PLDataSource * pDataSrc
    )
{
  PLBYTE * pData = pDataSrc->Read4Bytes ();
  return pData[3] + (pData[2]<<8) + (pData[1]<<16) + (pData[0]<<24);
}

#endif
/*
/--------------------------------------------------------------------
|
|      $Log: plpicdec.h,v $
|      Revision 1.10  2003/08/03 12:54:10  uzadow
|      Fixed broken linux build.
|
|      Revision 1.9  2003/08/03 12:03:20  uzadow
|      Added unicode support; fixed some header includes.
|
|      Revision 1.8  2003/03/19 14:33:13  uzadow
|      Added Rect.Contains
|
|      Revision 1.7  2003/02/15 21:26:58  uzadow
|      Added win32 version of url data source.
|
|      Revision 1.6  2002/08/04 20:08:01  uzadow
|      Added PLBmpInfo class, ability to extract metainformation from images without loading the whole image and proper greyscale support.
|
|      Revision 1.5  2002/03/06 22:46:54  uzadow
|      Fixed major PLAnyDec bug
|
|      Revision 1.4  2002/03/03 16:29:55  uzadow
|      Re-added BPPWanted.
|
|      Revision 1.3  2001/10/21 17:12:40  uzadow
|      Added PSD decoder beta, removed BPPWanted from all decoders, added PLFilterPixel.
|
|      Revision 1.2  2001/10/06 22:03:26  uzadow
|      Added PL prefix to basic data types.
|
|      Revision 1.1  2001/09/16 19:03:22  uzadow
|      Added global name prefix PL, changed most filenames.
|
|      Revision 1.8  2000/12/18 22:42:52  uzadow
|      Replaced RGBAPIXEL with PLPixel32.
|
|      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
|
|
\--------------------------------------------------------------------
*/

---