Hi All:
I have an application that allows the user to capture signatures on pre Palm
OS 3.5 devices then transfer them to a PC. That works fine.
I recently attempted to port it to Palm OS 3.5 and higher and was able to do
that successfully as well on the device. The problem lies in the conduit. I
am attempting to use the same conduit that I use for the pre Palm OS 3.5
application (since my signatures are using 1 pixel depth and only supported
on non-color devices), but when I save the signatures to the PC they all
start in the middle of the bitmap and wrap around to the beginning. Not
being an image or bitmap expert I am having problems resolving this issue.
I have attached the code below that writes the bitmap (this was originally
extracted from Signature++). Any impute would be appreciated.
- Martin
void WriteOutBitmap(CStdioFile& theLocalFile, WORD* theBitmapPtr)
{
BYTE theTempByte=0;
WORD* theData = theBitmapPtr;
WORD* theScanLine;
LONG theWidth, theHeight, theRowBytes;
LONG theBMPRowBytes;
BITMAPFILEHEADER theBitmapHeader; // 14 bytes
BITMAPINFOHEADER theBitmapInfo; // 40 bytes
RGBQUAD theBitmapColors[2]; // 8 bytes
int i, j;
// First, grab the important information from the pointer to the Palm OS
// bitmap.
theWidth = SyncHHToHostWord( *(theData++) );
theHeight = SyncHHToHostWord( *(theData++) );
theRowBytes = SyncHHToHostWord( *(theData++) );
// Advance past the rest of the Palm OS bitmap header information so that
// our pointer is sitting at the actual bitmap data.
theData+=5;
// Each scan line must end on a four-byte boundary, so calculate
// our BMP row bytes.
theBMPRowBytes = ((theRowBytes + 3)/4) * 4;
// First, fill in the file information structure
// Since we are writing a version 3 BMP file, the file size is the size of
the file header
// plus the size of the bitmap header plus the size of the color palette
plus the size of
// the bitmap data
theBitmapHeader.bfType = 0x4D42; // is always "BM";
theBitmapHeader.bfSize = sizeof( BITMAPFILEHEADER ) + sizeof(
BITMAPINFOHEADER ) + sizeof( theBitmapColors ) + (theHeight *
theBMPRowBytes);
theBitmapHeader.bfReserved1 = 0;
theBitmapHeader.bfReserved2 = 0;
theBitmapHeader.bfOffBits = sizeof( BITMAPFILEHEADER ) + sizeof(
BITMAPINFOHEADER ) + sizeof( theBitmapColors );
// Write out the header information to the file
theLocalFile.Write( &theBitmapHeader, sizeof(BITMAPFILEHEADER) );
// Next fill in the bitmap information structure
theBitmapInfo.biSize = sizeof( BITMAPINFOHEADER );
theBitmapInfo.biWidth = theWidth;
theBitmapInfo.biHeight = theHeight;
theBitmapInfo.biPlanes = 1;
theBitmapInfo.biBitCount = 1;
theBitmapInfo.biCompression = BI_RGB;
theBitmapInfo.biSizeImage = theHeight * theBMPRowBytes;
theBitmapInfo.biXPelsPerMeter = 0x0B13; // Default value
theBitmapInfo.biYPelsPerMeter = 0x0B13; // Default value
theBitmapInfo.biClrUsed = 2;
theBitmapInfo.biClrImportant = 2;
// Write out the bitmap information to the file
theLocalFile.Write( &theBitmapInfo, sizeof(BITMAPINFOHEADER) );
theBitmapColors[0].rgbBlue = 255;
theBitmapColors[0].rgbRed = 255;
theBitmapColors[0].rgbGreen = 255;
theBitmapColors[0].rgbReserved = 0;
theBitmapColors[1].rgbBlue = 0;
theBitmapColors[1].rgbRed = 0;
theBitmapColors[1].rgbGreen = 0;
theBitmapColors[1].rgbReserved = 0;
// Write out the header information to the file
theLocalFile.Write( &theBitmapColors, sizeof(theBitmapColors) );
// Write out each scan line from the bottom up, adding
// padding if necessary.
theTempByte = 0;
for (i=(theHeight-1); i>=0; i--)
{
// Grab a pointer to the scan line
theScanLine = theData + (i*(theRowBytes/2));
theLocalFile.Write( theScanLine, theRowBytes );
// Finally, add padding if necessary so that the
// bitmap is word aligned
if (theRowBytes != theBMPRowBytes)
{
for (j=theRowBytes; j<theBMPRowBytes; j++)
theLocalFile.Write( &theTempByte, 1 );
}
}
}
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