Scales an image by a given factor
#include <GDIPlus.au3>
_GDIPlus_ImageScale ( $hImage, $iScaleW, $iScaleH [, $iInterpolationMode = $GDIP_INTERPOLATIONMODE_HIGHQUALITYBICUBIC] )
| $hImage | A handle value |
| $iScaleW | A floating point value |
| $iScaleH | A floating point value |
| $iInterpolationMode | [optional] An integer value. Default is $GDIP_INTERPOLATIONMODE_HIGHQUALITYBICUBIC. |
| Success: | Returns a handle to a new Bitmap object |
| Failure: | 0 and sets the @error flag to non-zero. |
| @error: | 1 - unable to get width of image 2 - unable to get height of image 3 - unable to create new bitmap 4 - unable to create graphics context 5 - unable to set interpolation mode on graphics context 6 - unable to copy image to scaled bitmap |
Scale factor greater than 1 means enlarging the image whereas smaller than 1 means decrease the size.
_GDIPlus_BitmapCreateFromScan0, _GDIPlus_GraphicsDrawImageRect, _GDIPlus_GraphicsSetInterpolationMode, _GDIPlus_ImageGetGraphicsContext
#include <GDIPlus.au3>
#include <GUIConstantsEx.au3>
#include <ScreenCapture.au3>
#include <WinAPIHObj.au3>
Example()
Func Example()
_GDIPlus_Startup()
Local Const $iW = @DesktopWidth / 4, $iH = @DesktopHeight / 4
Local $hHBmp = _ScreenCapture_Capture("", 0, 0, $iW, $iH) ;create a GDI bitmap by capturing 1/16 of desktop
Local $hBitmap = _GDIPlus_BitmapCreateFromHBITMAP($hHBmp) ;convert GDI bitmap to GDI+ bitmap
_WinAPI_DeleteObject($hHBmp) ;release GDI bitmap resource because not needed anymore
Local $iScale = 2.75 ;1.0 is without any scaling
Local $hBitmap_Scaled = _GDIPlus_ImageScale($hBitmap, $iScale, $iScale, $GDIP_INTERPOLATIONMODE_NEARESTNEIGHBOR) ;scale image by 275% (magnify)
Local $hGUI = GUICreate("GDI+ test", $iW * $iScale, $iH * $iScale, -1, -1) ;create a test gui to display the resized image
GUISetState(@SW_SHOW)
Local $hGraphics = _GDIPlus_GraphicsCreateFromHWND($hGUI) ;create a graphics object from a window handle
_GDIPlus_GraphicsDrawImage($hGraphics, $hBitmap_Scaled, 0, 0) ;display scaled image
While 1
Switch GUIGetMsg()
Case $GUI_EVENT_CLOSE
ExitLoop
EndSwitch
WEnd
;cleanup resources
_GDIPlus_GraphicsDispose($hGraphics)
_GDIPlus_BitmapDispose($hBitmap)
_GDIPlus_BitmapDispose($hBitmap_Scaled)
_GDIPlus_Shutdown()
GUIDelete($hGUI)
EndFunc ;==>Example
#include <GDIPlus.au3>
#include <GUIConstantsEx.au3>
Example()
Func Example()
; Load an image
Local $sFile = FileOpenDialog("Select an image", "", "Image (*.jpg;*.png;*.bmp;*.gif;*.tif)")
If @error Then Exit MsgBox($MB_ICONWARNING, "Waring", "No image was selected! Exiting script...")
_GDIPlus_Startup()
Local $hBitmap = _GDIPlus_ImageLoadFromFile($sFile)
Local $aDim = _GDIPlus_ImageGetDimension($hBitmap)
Local $iScale = 4 ;1.0 is without any scaling
Local $hBitmap_Scaled = _GDIPlus_ImageScale($hBitmap, $iScale, $iScale, 4)
Local $hGUI = GUICreate("GDI+ test", $aDim[0] * $iScale, $aDim[1] * $iScale, -1, -1) ;create a test gui to display the resized image
GUISetState(@SW_SHOW)
Local $hGraphics = _GDIPlus_GraphicsCreateFromHWND($hGUI) ;create a graphics object from a window handle
_GDIPlus_GraphicsDrawImage($hGraphics, $hBitmap_Scaled, 0, 0) ;display scaled image
While 1
Switch GUIGetMsg()
Case $GUI_EVENT_CLOSE
ExitLoop
EndSwitch
WEnd
;cleanup resources
_GDIPlus_GraphicsDispose($hGraphics)
_GDIPlus_BitmapDispose($hBitmap)
_GDIPlus_BitmapDispose($hBitmap_Scaled)
_GDIPlus_Shutdown()
GUIDelete($hGUI)
EndFunc ;==>Example