Found a piece of code on the net, this should be the fastest (do not use GDI +), especially for a larger version, but it is rotated 90 degrees, how to make it spin - 90 degrees, tall person to give directions, thank you first!

Procedure Rotate270 (Bitmap: TBitmap);
Var
AStream: TMemorystream;
//memory flow
Header: TBITMAPINFO;
Dc: hDC.
P: ^ THelpRGB;
X, y, w, h: Integer;//w width, height h
RowOut: pRGBArray;
The begin
//create a memory stream
AStream:=TMemoryStream. Create;
//set size, must be in multiples of 4
AStream. SetSize (Bitmap. The Bitmap Height *. Width * 4);
With the header. The bmiHeader do//bitmap file
The begin
BiSize:=SizeOf (TBITMAPINFOHEADER);//size
BiWidth:=Bitmap. The Width;//bitmap width
BiHeight:=Bitmap. The Height;//bitmap high
BiPlanes:=1;
BiBitCount:=32;
//no compression
BiCompression:=0;
BiSizeimage:=aStream. Size;
BiXPelsPerMeter:=1;//horizontal resolution
BiYPelsPerMeter:=1;//vertical resolution
BiClrUsed:=0;
BiClrImportant:=0;
end;
Dc:=GetDC (0);
P:=aStream. The Memory;
GetDIBits (dc, Bitmap. The Handle, 0, Bitmap. The Height, P, header, dib_RGB_Colors);
ReleaseDC (0, dc);
H:=bitmap. The Height;//source high figure
W:=bitmap. The Width;//source map width
//specify to create bitmap size
Bitmap. Width:=h;
Bitmap. Height:=w;
For: y=0 to (w - 1) do
The begin
RowOut:=Bitmap. ScanLine [y];//get the new bitmap information
P:=aStream. The Memory;//set the file pointer
Inc (p, y);//pointer shift
For: x=0 to (h - 1) do
The begin
Rowout [x] :=p ^. RGB.//data transfer
Inc (p, w);
end;
end;
AStream. Free;//release resources
end;

CodePudding user response:

Procedure TForm1. Button1Click (Sender: TObject);
Var
WicImg: TWICImage;
The Factory: IWICImagingFactory; {class factory interface}
FlipRotator: IWICBitmapFlipRotator; {rotation transformation interface}
The begin
{establish TWICImage first class and load the picture}
WicImg:=TWICImage. Create;
WicImg. LoadFromFile (' c: \ temp \ test. JPG); {get class factory interface}
The Factory:=WicImg. ImagingFactory; {let plants rotation transformation interface}
Factory. CreateBitmapFlipRotator (FlipRotator); {perform rotation transformation, here is the rotation Angle of 90 degrees; Note data after the rotation in FlipRotator}

FlipRotator. The Initialize (WicImg. Handle, WICBitmapTransformRotate270); The image in {update TWICImage}
WicImg. Handle:=IWicBitmap (FlipRotator); {at}
Canvas. The Draw (0, 0, WicImg); Released {}
FlipRotator:=nil; The Factory:=nil; WicImg. Free;
end;//or the above procedures, gave some return value judgment procedure TForm1. Button2Click (Send

CodePudding user response:

USES Wincodec

CodePudding user response:

Thank you for your reply, upstairs haven't read it, slowly study,

In addition I the above code Rotate270 (Bitmap: TBitmap), 270 should be 90, forget to change, I am want to change on the original code to rotate 270 degrees, the result not to get into,

CodePudding user response:

Remember there are directly under the Windows API for image deformation of the API

CodePudding user response:

According to the file format to manipulate files directly,

CodePudding user response:

Use gdi +, otherwise very trouble,

CodePudding user response:

Good learning how to learn