Reply To: Making a scanning preview

[GaaraTheKasekage]

Can be this part of the problem maybe is not the triplet at all maybe it is the bmp watch this code:

function TTwainSource.PrepareMemXfer(var BitmapHandle: HBitmap; var PixelType: TW_INT16): TW_UINT16;

const

PixelColor: Array[TTwainPixelFlavor] of Array[0..1] of Byte =

((0, $FF), ($FF, 00), (0, $FF));

var

Handle: HGlobal;

Info: TW_IMAGEINFO;

Setup: TW_SETUPMEMXFER;

structsize, index, Size, Blocks: Integer;

XRes, YRes: Extended;

Pal   : TW_PALETTE8;

vUnit : TTwainUnit;

vUnits: TTwainUnitSet;

Dib   : pBitmapInfo;

PixelFlavor: TTwainPixelFlavor;

PixelFlavors: TTwainPixelFlavorSet;

DC: HDC;

Data  : Pointer;

begin

{First of all, get information on the image being acquired}

Result := Owner.TwainProc(AppInfo, @Structure, DG_IMAGE, DAT_IMAGEINFO,MSG_GET, @Info);

if Result <> TWRC_SUCCESS then exit;



{Calculate image size}

with Info do

size := ((((ImageWidth * BitsPerPixel + 31) div 32)*4) * info.ImageLength);



{Obtain image buffer transference sizes}

Owner.TwainProc(AppInfo, @Structure, DG_CONTROL, DAT_SETUPMEMXFER, MSG_GET, @Setup);

blocks := (size div Integer(setup.Preferred));

size := (blocks + 1) * Integer(setup.Preferred);



{Prepare new bitmap}

structsize := size + sizeof(BITMAPINFOHEADER) + 256 * sizeof(RGBQUAD);



Handle := GlobalAlloc(GHND, StructSize);

Dib := GlobalLock(Handle);

Fillchar(Dib^, structsize, #0);

{Fill image information}

Dib^.bmiHeader.biSize := sizeof(BITMAPINFOHEADER);

Dib^.bmiHeader.biWidth := info.ImageWidth;

Dib^.bmiHeader.biHeight := info.ImageLength;

{Only 1 plane supported}

Dib^.bmiHeader.biPlanes := 1;

Dib^.bmiHeader.biBitCount := info.BitsPerPixel;

{No compression}

Dib^.bmiHeader.biCompression := BI_RGB;

Dib^.bmiHeader.biSizeImage := Size;



{Adjust units}

XRes := Fix32ToFloat(Info.XResolution);

YRes := Fix32ToFloat(Info.YResolution);

GetICapUnits(vUnit, vUnits);

case vUnit of

tuInches: begin

Dib^.bmiHeader.biXPelsPerMeter := Trunc((XRes*2.54)*100);

Dib^.bmiHeader.biYPelsPerMeter := Trunc((YRes*2.54)*100);

end;

tuCentimeters: begin

Dib^.bmiHeader.biXPelsPerMeter := Trunc(XRes*100);

Dib^.bmiHeader.biYPelsPerMeter := Trunc(YRes*100);

end

else begin

Dib^.bmiHeader.biXPelsPerMeter := 0;

Dib^.bmiHeader.biYPelsPerMeter := 0;

end

end {case vUnits of};



{Now it should setup the palette to be used by the image}

{by either building a definied palette or retrieving the}

{image's one}

Did u do something like this?