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How to select a rectangular portion of a TImage Bitmap?

How to select a rectangular portion of a TImage Bitmap?

How to select a rectangular portion of a TImage Bitmap?

I have a Bitmap image and need to select a particular position rectangular to select this position I must save her.

Example: Picture 800x600 size to be located / copied somewhere 300x400 photo where is the face of a person.

I found several examples but none that me an idea of ​​how to do this sad Examples for very complex tasks that I will not use. If I have not been clear, let me know. Sorry for my english.

RE: How to select a rectangular portion of a TImage Bitmap?

Hi jhcbrito...

I hope this is usefull... Use TCanvas.CopyRect method.

Code examples from Embarcadero.

The following code illustrates the differences between
CopyRect and BrushCopy. The bitmap graphic ‘FACTORY.BMP’ is
loaded into Bitmap and displayed on the Canvas of Form1.
BrushCopy replaces the color black in the graphic with the
brush of the canvas, while CopyRect leaves the colors intact.
procedure TForm1.Button1Click(Sender: TObject);
Bitmap: TBitmap;
MyRect, MyOther: TRect;
MyRect := Rect(10,10,150,150);
MyOther := Rect(10,161,150,301);
Bitmap := TBitmap.Create;
'c:\Program Files\Common Files\CodeGear Shared\Images\Splash\256color\factory.bmp');
Form1.Canvas.BrushCopy(MyRect, Bitmap, MyRect, clBlack);
Copy Code
The following example uses the CopyMode of an image’s canvas
to blank out the image when the user chooses the "Cut" menu
item. This example requires a Main menu with a Copy and a
Cut menu item that have their OnClick error handlers populated.
Note: CopyMode and CopyRect are members of the destination
procedure TForm1.Copy1Click(Sender: TObject);
DstRect, SrcRect: TRect;
with Image2.Canvas do
CopyMode := cmSrcCopy;
DstRect := Rect(0, 0, Image2.Width, Image2.Height);
SrcRect := Rect(0, 0, Image1.Width, Image1.Height);
CopyRect(DstRect, Image1.Canvas, SrcRect);

procedure TForm1.Cut1Click(Sender: TObject);
ARect: TRect;
Copy1Click(Sender); { do the same thing as the copy menu item }
with Image1.Canvas do
CopyMode := cmWhiteness;
ARect := Rect(0, 0, Image1.Width, Image1.Height);
CopyRect(ARect, Image1.Canvas, ARect);
CopyMode := cmSrcCopy; { restore the copy mode }

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