Re: Grabbing the pixels of a bmp

From:

"Jack" <jl@knight.com>

Newsgroups:

microsoft.public.vc.language

Date:

Fri, 26 May 2006 10:55:55 +0800

Message-ID:

<OyEyu$GgGHA.3588@TK2MSFTNGP02.phx.gbl>

==================== still no good
pBitmap->GetBitmap(&bmpX);
  //LPVOID bmpinfo = new BYTE[sizeof(BITMAP)];
  //pBitmap->GetObject(sizeof(BITMAP), bmpinfo);
  BYTE* bmpBuffer = (BYTE *)GlobalAlloc (GPTR, bmpX.bmWidth*bmpX.bmHeight);
  pBitmap->GetBitmapBits(bmpX.bmWidthBytes*bmpX.bmHeight,bmpBuffer);
  for (int i = 0; i < ds.dsBm.bmHeight; i++) {
   for (int j = 0; j < ds.dsBm.bmWidth; j+=4) { // 32 bit bitmap
    if (bmpBuffer[i*ds.dsBm.bmHeight+j] == 255 &&
bmpBuffer[i*ds.dsBm.bmHeight+j+1] == 0 &&
        bmpBuffer[i*ds.dsBm.bmHeight+j+2] == 0 &&
bmpBuffer[i*ds.dsBm.bmHeight+j+3] == 255)
           AfxMessageBox ("Hit it", MB_OK, NULL);

=====================
"Jack" <jl@knight.com> ???g???l???s?D:uUwxK2GgGHA.1204@TK2MSFTNGP02.phx.gbl...

Still doesn't work
pBitmap->GetBitmap(&bmpX);
//LPVOID bmpinfo = new BYTE[sizeof(BITMAP)];
//pBitmap->GetObject(sizeof(BITMAP), bmpinfo);
  BYTE* bmpBuffer = (BYTE *)GlobalAlloc (GPTR,
bmpX.bmWidth*bmpX.bmHeight);
pBitmap->GetBitmapBits(bmpX.bmWidthBytes*bmpX.bmHeight,bmpBuffer);
for (int i = 0; i < ds.dsBm.bmHeight; i) {
  for (int j = 0; j < ds.dsBm.bmWidth; j=4) { // 32 bit bitmap
   if (bmpBuffer[i*ds.dsBm.bmHeight] == 0 && bmpBuffer[i*ds.dsBm.bmHeight??]
== 0 &&
    bmpBuffer[i*ds.dsBm.bmHeight??] == 255)
    AfxMessageBox ("Hit it", MB_OK, NULL);

----------------------------------------
"Jack" <jl@knight.com> ???gco?l?Do?Ps?D:%23i33krGgGHA.4172@TK2MSFTNGP04.phx.gbl...

The problem I am having now is the bitmap pointer is byte-based.
I want to read 24 to 32 bit bitmaps
Any comments?
Jack

"Jack" <jl@knight.com> ???gco?l?FDo!Ps?D:OjJxcaGgGHA.1204@TK2MSFTNGP02.phx.gbl...

"doug mansell" <doug_mansell@hotmail.com>
???????:umIGUg$fGHA.3916@TK2MSFTNGP04.phx.gbl...

Jack wrote:

Hi,
I wonder how to grab the 'current' pixel of a bitmap
say
*****************
*((**************)

is the bitmap
I want to get the first row, first column pixel value
How do I do that in VC?
Thanks
Jack

You could read about this function: GetBitmapBits

doesn't work either
pBitmap->GetBitmap(&bmpX);
BYTE* bmpBuffer = (BYTE *)GlobalAlloc (GPTR,
bmpX.bmWidth*bmpX.bmHeight);
for (int i = 0; i < ds.dsBm.bmHeight; i) {
  for (int j = 0; i < ds.dsBm.bmWidth; j) {
   if (bmpBuffer[i*ds.dsBm.bmHeight] == RGB(255,255,0))
       AfxMessageBox ("Hit it", MB_OK, NULL);
  }
}
}