ActiveDelphi

[douglas_kussler]

Bom dia Pessoal,
Encontrei uma função para redimensionar imagens utilizando varias extensões de arquivos: bmp, png, jpg, gif.
Ocorre que estou utilizando uma imagem do disco para passar para a function..

function ResizeImage(const ASource, ADest: String; const AWidth,
AHeight: Integer; const ABackColor: TColor;
const AType: TImageType = itUnknown): Boolean;
var
fsSource: TFileStream;
fsDest: TFileStream;
begin
Result := False;
fsSource := TFileStream.Create(ASource, fmOpenRead);
try
fsDest := TFileStream.Create(ADest, fmCreate);
try
Result := not Result; //hide compiler hint
Result := ResizeImage(fsSource, fsDest, AWidth, AHeight, ABackColor, AType);
finally
FreeAndNil(fsDest);
end;
finally
FreeAndNil(fsSource);
end;
end;

Essa function pega a imagem que passei carrega em um TFileStream e chama outra function onde o parametro é TStream. Ocorre que após chegar nessa nova function, o conteudo do TStream de origem e destino ficam vazios.

function ResizeImage(const ASource, ADest: TStream; const AWidth,
AHeight: Integer; const ABackColor: TColor;
const AType: TImageType = itUnknown): Boolean;
var
itImage: TImageType;
ifImage: TImageInfo;
bmpTemp: TBitmap;
bmpSource: TBitmap32;
bmpResized: TBitmap32;
cBackColor: TColor32;
rSource: TRect;
rDest: TRect;
dWFactor: Double;
dHFactor: Double;
dFactor: Double;
iSrcWidth: Integer;
iSrcHeight: Integer;
iWidth: Integer;
iHeight: Integer;
jpgTemp: TJPEGImage;
begin
Result := False;
itImage := AType;
if itImage = itUnknown then
begin
ifImage := GetImageInfo(ASource);
itImage := ifImage.ImgType;
if itImage = itUnknown then
Exit;
end;
bmpTemp := TBitmap.Create();
try
case itImage of
itBMP: bmpTemp.LoadFromStream(ASource);
itGIF: GIFToBMP(ASource, bmpTemp);
itJPG: JPGToBMP(ASource, bmpTemp);
itPNG: PNGToBMP(ASource, bmpTemp);
end;
bmpSource := TBitmap32.Create();
bmpResized := TBitmap32.Create();
try
cBackColor := Color32(ABackColor);
bmpSource.Assign(bmpTemp);
bmpResized.Width := AWidth;
bmpResized.Height := AHeight;
bmpResized.Clear(cBackColor);
iSrcWidth := bmpSource.Width;
iSrcHeight := bmpSource.Height;
iWidth := iSrcWidth;
iHeight := iSrcHeight;
with rSource do
begin
Left := 0;
Top := 0;
Right := iSrcWidth;
Bottom := iSrcHeight;
end;
if (iWidth > AWidth) or (iHeight > AHeight) then
begin
dWFactor := AWidth / iWidth;
dHFactor := AHeight / iHeight;
if (dWFactor > dHFactor) then
dFactor := dHFactor
else
dFactor := dWFactor;
iWidth := Floor(iWidth * dFactor);
iHeight := Floor(iHeight * dFactor);
end;
with rDest do
begin
Left := Floor((AWidth - iWidth) / 2);
Top := Floor((AHeight - iHeight) / 2);
Right := Left + iWidth;
Bottom := Top + iHeight;
end;
bmpSource.Resampler := TKernelResampler.Create;
TKernelResampler(bmpSource.Resampler).Kernel := TLanczosKernel.Create;
bmpSource.DrawMode := dmOpaque;
bmpResized.Draw(rDest, rSource, bmpSource);
bmpTemp.Assign(bmpResized);
jpgTemp := TJPEGImage.Create();
jpgTemp.CompressionQuality := 80;
try
jpgTemp.Assign(bmpTemp);
jpgTemp.SaveToStream(ADest);
Result := True;
finally
FreeAndNil(jpgTemp);
end;
finally
FreeAndNil(bmpResized);
FreeAndNil(bmpSource);
end;
finally
FreeAndNil(bmpTemp);
end;
end;

Esse campo ASource do tipo TStream fica vazio ao receber o parametro da primeira function. Eu devo passar de outra forma esse TFileStream para o TStream?

Desde ja agradeço