utilities/CxImage/ximawbmp.cpp

   1 /*
   2  * File:        ximawbmp.cpp
   3  * Purpose:     Platform Independent WBMP Image Class Loader and Writer
   4  * 12/Jul/2002 Davide Pizzolato - www.xdp.it
   5  * CxImage version 6.0.0 02/Feb/2008
   6  */
   7
   8 #include "ximawbmp.h"
   9
  10 #if CXIMAGE_SUPPORT_WBMP
  11
  12 #include "ximaiter.h"
  13
  14 ////////////////////////////////////////////////////////////////////////////////
  15 #if CXIMAGE_SUPPORT_DECODE
  16 ////////////////////////////////////////////////////////////////////////////////
  17 bool CxImageWBMP::Decode(CxFile *hFile)
  18 {
  19         if (hFile == NULL) return false;
  20
  21         WBMPHEADER wbmpHead;
  22
  23   cx_try
  24   {
  25         ReadOctet(hFile, &wbmpHead.Type);
  26
  27         DWORD dat;
  28         ReadOctet(hFile, &dat);
  29         wbmpHead.FixHeader = (BYTE)dat;
  30
  31         ReadOctet(hFile, &wbmpHead.ImageWidth);
  32         ReadOctet(hFile, &wbmpHead.ImageHeight);
  33
  34         if (hFile->Eof())
  35                 cx_throw("Not a WBMP");
  36
  37         if (wbmpHead.Type != 0)
  38                 cx_throw("Unsupported WBMP type");
  39
  40         head.biWidth = wbmpHead.ImageWidth;
  41         head.biHeight= wbmpHead.ImageHeight;
  42
  43         if (head.biWidth<=0 || head.biHeight<=0)
  44                 cx_throw("Corrupted WBMP");
  45
  46         if (info.nEscape == -1){
  47                 info.dwType = CXIMAGE_FORMAT_WBMP;
  48                 return true;
  49         }
  50
  51         Create(head.biWidth, head.biHeight, 1, CXIMAGE_FORMAT_WBMP);
  52         if (!IsValid()) cx_throw("WBMP Create failed");
  53         SetGrayPalette();
  54
  55         int linewidth=(head.biWidth+7)/8;
  56     CImageIterator iter(this);
  57         iter.Upset();
  58     for (long y=0; y < head.biHeight; y++){
  59                 hFile->Read(iter.GetRow(),linewidth,1);
  60                 iter.PrevRow();
  61     }
  62
  63   } cx_catch {
  64         if (strcmp(message,"")) strncpy(info.szLastError,message,255);
  65         return FALSE;
  66   }
  67     return true;
  68 }
  69 ////////////////////////////////////////////////////////////////////////////////
  70 bool CxImageWBMP::ReadOctet(CxFile * hFile, DWORD *data)
  71 {
  72         BYTE c;
  73         *data = 0;
  74         do {
  75                 if (hFile->Eof()) return false;
  76                 c = (BYTE)hFile->GetC();
  77                 *data <<= 7;
  78                 *data |= (c & 0x7F);
  79         } while ((c&0x80)!=0);
  80         return true;
  81 }
  82 ////////////////////////////////////////////////////////////////////////////////
  83 #endif //CXIMAGE_SUPPORT_DECODE
  84 ////////////////////////////////////////////////////////////////////////////////
  85 #if CXIMAGE_SUPPORT_ENCODE
  86 ////////////////////////////////////////////////////////////////////////////////
  87 bool CxImageWBMP::Encode(CxFile * hFile)
  88 {
  89         if (EncodeSafeCheck(hFile)) return false;
  90
  91         //check format limits
  92         if (head.biBitCount!=1){
  93                 strcpy(info.szLastError,"Can't save this image as WBMP");
  94                 return false;
  95         }
  96
  97         WBMPHEADER wbmpHead;
  98         wbmpHead.Type=0;
  99         wbmpHead.FixHeader=0;
 100         wbmpHead.ImageWidth=head.biWidth;
 101         wbmpHead.ImageHeight=head.biHeight;
 102
 103     // Write the file header
 104         hFile->PutC('\0');
 105         hFile->PutC('\0');
 106         WriteOctet(hFile,wbmpHead.ImageWidth);
 107         WriteOctet(hFile,wbmpHead.ImageHeight);
 108     // Write the pixels
 109         int linewidth=(wbmpHead.ImageWidth+7)/8;
 110     CImageIterator iter(this);
 111         iter.Upset();
 112     for (DWORD y=0; y < wbmpHead.ImageHeight; y++){
 113                 hFile->Write(iter.GetRow(),linewidth,1);
 114                 iter.PrevRow();
 115     }
 116         return true;
 117 }
 118 ////////////////////////////////////////////////////////////////////////////////
 119 bool CxImageWBMP::WriteOctet(CxFile * hFile, const DWORD data)
 120 {
 121         int ns = 0;
 122         while (data>>(ns+7)) ns+=7;
 123         while (ns>0){
 124                 if (!hFile->PutC(0x80 | (BYTE)(data>>ns))) return false;
 125                 ns-=7;
 126         }
 127         if (!(hFile->PutC((BYTE)(0x7F & data)))) return false;
 128         return true;
 129 }
 130 ////////////////////////////////////////////////////////////////////////////////
 131 #endif // CXIMAGE_SUPPORT_ENCODE
 132 ////////////////////////////////////////////////////////////////////////////////
 133 #endif // CXIMAGE_SUPPORT_WBMP
 134