Changing Bitmap colors...

[digelo]

Hi
I got a bitmap picture i need to change it to black and white and then negative all colors in it ...
Can anybody gimme a clue ?

[dedndave]

i assume you mean greyscale

Y = 0.587G + 0.299R + 0.114B

Y = luminance
set R, G, B all to the same Y value

to make it negative, 0FFh-Y

[donkey]

I posted code quite a long time ago to create a litho of an image, that is only black or white, no grey scale. I also posted greyscale code if you need it. You can find the code in my graphics library, only good for 32bit DIBs though. InvertImage might be what you want for your negative colors, its also in the lib.

Graphics.lib

(source is included)

[digelo]

My mind stuck ...

i used graphic lib but when i translated it to masm my translated code didnt work ,then i found another example (http://www.masm32.com/board/index.php?topic=2640.0 ) but again when i added it to my application , its didnt grayed my bitmap.
I guess i have somekinda problem with bitmaps or converting my bitmap to a compatible bitmap  for those exapmles.

i used bitblt for copying my bitmap to a bitmap that i prepared for those examples but destination bitmap was colorful  lol

i put my code with explaining about what exactly i wanna do:
i got a bitmap that i print it , i want to print it in grayscale and negative colors then result would save inc and ganna be more beauty.

Code Select Expand


PrintStuff  proc 
LOCAL _di:DOCINFO
LOCAL p2:PRINTDLG
LOCAL p_dim:POINT
LOCAL p_dim2:POINT
LOCAL psd:PAGESETUPDLG
LOCAL sci:SCROLLINFO

LOCAL memdc :DWORD
LOCAL hbmp :DWORD
LOCAL xxWidth:DWORD
LOCAL bmp :BITMAP


invoke memfill, addr _di,sizeof DOCINFO,0
mov _di.cbSize,sizeof DOCINFO

mov _di.lpszDocName,eax
mov _di.lpszOutput,0
mov _di.lpszDatatype,0
mov _di.fwType,0

invoke memfill, addr p2,sizeof PRINTDLG-4,0
mov p2.lStructSize,sizeof PRINTDLG
mov p2.Flags,PD_RETURNDC or PD_USEDEVMODECOPIESANDCOLLATE
      mov p2.nToPage,1000
      mov p2.nMinPage,1
      mov p2.nMaxPage,1000
     
      invoke PrintDlg,addr p2
      .if eax!=0
      .if p2.hDC==0
      invoke MessageBox,0,CADD("Printer DC is wrong"),0,0
      .endif
     
      invoke GetDeviceCaps,p2.hDC,HORZRES
      mov p_dim.x,eax
      invoke GetDeviceCaps,p2.hDC,VERTRES
      mov p_dim.y,eax
     
     
     
      invoke StartDoc,p2.hDC,addr _di
      .if eax==SP_ERROR
      invoke MessageBox,0,CADD("Cannot start, document"),0,0
      .endif
     
      invoke StartPage,p2.hDC
      .if eax<=0
      invoke MessageBox,0,CADD("Cannot start printer"),0,0
      .endif
     
     
     
           
invoke CreateCompatibleDC,p2.hDC
mov memdc,eax
invoke CreateCompatibleBitmap,p2.hDC,p_dim.x,p_dim.y
mov hbmp,eax
invoke SelectObject,memdc,hbmp

push eax

invoke GetObject,hbmp,SIZEOF bmp,ADDR bmp

mov sci.cbSize,SIZEOF sci
mov sci.fMask,SIF_POS
invoke GetScrollInfo,hChild1,SB_VERT,ADDR sci

.if hReflex == 1
mov xxWidth,535
.else
mov xxWidth,423
.endif


invoke StretchBlt,memdc,0,0,bmp.bmWidth,bmp.bmHeight,hDrawDC,0,sci.nPos,xxWidth,663,SRCCOPY

invoke BitBlt,p2.hDC,0,15,bmp.bmWidth,bmp.bmHeight,memdc,0,0, SRCCOPY

pop eax
invoke SelectObject,memdc,eax
invoke DeleteDC,memdc
invoke DeleteObject,hbmp
;;;
        invoke EndPage,p2.hDC
      invoke EndDoc,p2.hDC
      invoke DeleteDC,p2.hDC
     
      .endif

    ret
PrintStuff endp