This function is used to allow access to pixels in the Device Independent Bitmap (DIB). This method is to be used in conjunction with the IKEndDibAccess function.
Parameters
| Name | Explanation |
|---|---|
| hDib | The raster image memory handle (supports 1, 4, 8, 16. 24, and 32 bit images) |
| stpDibInfo | A structure variable (user-defined type) that retrieves DIB information |
Return Value
Returns True (nonzero) if successful. Returns False (0) if unsuccessful.
Explanation
The IKStartDibAccess function is used to allow access to pixels in the Device Independent Bitmap (DIB). This method is to be used in conjunction with the IKEndDibAccess function.
For more information about IKDIB_INFO, please refer to the explanation of the IKDIB_INFO member variables at the beginning of the Ik9Effect.dll section.
To access the DIB and manipulate pixel data, you must use the following functions as a group.
IKStartDibAccess
l
IKGetDibPixel, IKSetDibPixel
l
IKEndDibAccess
Sample Code
The following code starts access to the DIB, then loops through each pixel in the image, using the IKGetDibPixel function to retrieve the pixels' rgb values. Then those values are reversed and set using the IKSetDibPixel function.
(1)Delphi
Handle: THandle;
ImageInfo: IKIMAGE_INFO;
DibInfo: IKDIB_INFO;
Ret: LongBool;
i, j: Integer;
Handle := IKFileLoad('newtone.bmp', 0, 0, 0, 0, nil, nil, nil);
if Handle = 0 then Exit;
Ret := IKGetImageType(Handle, ImageInfo);
Ret := IKStartDibAccess(Handle, DibInfo);
for i := 0 to ImageInfo.Height - 1 do
begin
for j := 0 to ImageInfo.Width - 1 do
begin
Ret := IKGetDibPixel(DibInfo, j, i);
if ImageInfo.BitCount = 1 then
begin
if DibInfo.PalNo <> 0 then
DibInfo.PalNo := 0
else
DibInfo.PalNo := 1;
end
else if ImageInfo.BitCount > 8 then
begin
DibInfo.Blue := 255 - DibInfo.Blue;
DibInfo.Green := 255 - DibInfo.Green;
DibInfo.Red := 255 - DibInfo.Red;
end;
Ret := IKSetDibPixel(DibInfo, j, i);
end;
end;
Ret := IKEndDibAccess(Handle, DibInfo);
Ret := IKBmpFileSave('newtone.bmp', Handle, False, 0, nil, nil, nil);
IKFreeMemory(Handle);
(2)Visual Basic
Dim Handle As Long
Dim ImageInfo As IKIMAGE_INFO
Dim DibInfo As IKDIB_INFO
Dim Ret As Long
Dim i As Long, j As Long
Handle = IKFileLoad("newtone.bmp", 0, 0, 0, 0, "", "", "")
If Handle = 0 Then Exit Sub
Ret = IKGetImageType(Handle, ImageInfo)
Ret = IKStartDibAccess(Handle, DibInfo)
For i = 0 To ImageInfo.Height - 1
For j = 0 To ImageInfo.Width - 1
Ret = IKGetDibPixel(DibInfo, j, i)
If ImageInfo.BitCount = 1 Then
If DibInfo.PalNo <> 0 Then
DibInfo.PalNo = 0
Else
DibInfo.PalNo = 1
End If
Else If ImageInfo.BitCount > 8 Then
DibInfo.Blue = 255 - DibInfo.Blue
DibInfo.Green = 255 - DibInfo.Green
DibInfo.Red = 255 - DibInfo.Red
End If
Ret = IKSetDibPixel(DibInfo, j, i)
Next j
Next i
Ret = IKEndDibAccess(Handle, DibInfo)
Ret = IKBmpFileSave("newtone.bmp", Handle, False, 0, "", "", "")
IKFreeMemory(Handle)