_ScreenCapture_CaptureWnd not capturing window.

[Schoening]

I am trying to take a screenshot of a window that is not in the foreground.

I read the help file and I searched the forum. But somehow I just can't get it to work...

I tried multiple versions. Noone work. They simply capture my current screen OR capture a small black rectangle.

#include <ScreenCapture.au3>

Main()

Func Main()
   Local $handle
   $handle = WinGetHandle("Untitled - Notepad");
   ; Capture window
   _ScreenCapture_CaptureWnd(@MyDocumentsDir & "\test.jpg", $handle);

   ShellExecute(@MyDocumentsDir & "\test.jpg")

EndFunc

#include <ScreenCapture.au3>

Main()

Func Main()
   Local $handle
   $handle = 0x00AC05BA
   ; Capture window
   _ScreenCapture_CaptureWnd(@MyDocumentsDir & "\test.jpg", $handle);

   ShellExecute(@MyDocumentsDir & "\test.jpg")

EndFunc

Any Ideas why this is not working? I am trying to build a browser based streaming service. So it would be great if I could capture windows that are not in the front.

[UEZ]

If you are using Vista / Server 2008 try this:

#include <ScreenCapture.au3>

Main()

Func Main()
   Local $handle
   $handle = WinGetHandle("Untitled - Notepad");
   ; Capture window
   _GDIPlus_Startup("gdiplus.dll")
   _ScreenCapture_CaptureWnd(@MyDocumentsDir & "\test.jpg", $handle);
   _GDIPlus_Shutdown()

   ShellExecute(@MyDocumentsDir & "\test.jpg")

EndFunc

Br,

UEZ

[Schoening]

Thanks for the help

I am on Windows 8.1

But your example did get me slightly further. The screenshot now takes an image of whatever is at the position of the notepad window.  So basically like a _ScreenCapture_Capture with set position.

[Malkey]

This example is working on WIN_7/Service Pack 1.

expandcollapse popup

#include <ScreenCapture.au3>
#include <WinAPIConstants.au3>
Opt("WinTitleMatchMode", -2) ;1=start, 2=subStr, 3=exact, 4=advanced, -1 to -4=Nocase

_ScreenCaptureWnd(" - notepad")


Func _ScreenCaptureWnd($sWinTitle)
    Local $iMin = BitAND(WinGetState($sWinTitle), 16) ; Check if $sWinTitle window is minimized.
    ;ConsoleWrite($iMin & @LF)

    If $iMin <> 16 Then ; If not minimized
        Local $aWinList = WinList()
        For $i = 1 To UBound($aWinList) - 1
            If BitAND($aWinList[$i][1], 8) Then ; Get the top-most (active) window.
                $hTopMost = $aWinList[$i][0]
                ExitLoop
            EndIf
        Next
    Else ; If minimized
        WinSetState($sWinTitle, "", @SW_SHOW)
    EndIf

    WinActivate($sWinTitle)
    WinWaitActive($sWinTitle)
    Local $aWinPos = WinGetPos($sWinTitle) ; Get original position of $sWinTitle window.
    WinMove($sWinTitle, "", 0, 0) ; In case $sWinTitle window is partly off desktop area.

    _ScreenCapture_CaptureWnd(@MyDocumentsDir & "\test.jpg", WinGetHandle($sWinTitle))

    WinMove($sWinTitle, "", $aWinPos[0], $aWinPos[1]) ; Re-position $sWinTitle window.

    If $iMin <> 16 Then ; If not minimized
        WinActivate($hTopMost)
        WinWaitActive($hTopMost) ; Re-establish original top-most (active) window.
    Else ; If minimized
        WinSetState($sWinTitle, "", @SW_MINIMIZE)
    EndIf
    ShellExecute(@MyDocumentsDir & "\test.jpg")
EndFunc   ;==>_ScreenCaptureWnd

[Schoening]

Thanks Malkey

It works.

But sadly it relies on putting the window in the front. I was hoping to take a screenshot in the background. Similar to streaming video.

I guess I look into Python and other options

[UEZ]

Then try this:

expandcollapse popup

#include <GDIPlus.au3>

_GDIPlus_Startup()
Global $handle = WinGetHandle("[CLASS:Notepad]")
Global $hBitmap = Capture_Window($handle, _WinAPI_GetWindowWidth($handle), _WinAPI_GetWindowHeight($handle))
_GDIPlus_ImageSaveToFile($hBitmap, @ScriptDir & "\test.jpg")
_GDIPlus_Shutdown()

ShellExecute(@ScriptDir & "\test.jpg")


Func Capture_Window($hWnd, $w, $h)
    If Not IsHWnd($hWnd) Then Return SetError(1, 0, 0)
    If Int($w) < 1 Then Return SetError(2, 0, 0)
    If Int($h) < 1 Then Return SetError(3, 0, 0)
    Local Const $hDC_Capture = _WinAPI_GetDC(HWnd($hWnd))
    Local Const $hMemDC = _WinAPI_CreateCompatibleDC($hDC_Capture)
    Local Const $hHBitmap = _WinAPI_CreateCompatibleBitmap($hDC_Capture, $w, $h)
    Local Const $hObjectOld = _WinAPI_SelectObject($hMemDC, $hHBitmap)
    DllCall("gdi32.dll", "int", "SetStretchBltMode", "hwnd", $hDC_Capture, "uint", 4)
    DllCall("user32.dll", "int", "PrintWindow", "hwnd", $hWnd, "handle", $hMemDC, "int", 0)

    _WinAPI_DeleteDC($hMemDC)
    _WinAPI_SelectObject($hMemDC, $hObjectOld)
    _WinAPI_ReleaseDC($hWnd, $hDC_Capture)

    Local Const $hFullScreen = WinGetHandle("[TITLE:Program Manager;CLASS:Progman]")
    Local Const $aFullScreen = WinGetPos($hFullScreen)
    Local Const $c1 = $aFullScreen[2] - @DesktopWidth, $c2 = $aFullScreen[3] - @DesktopHeight
    Local Const $wc1 = $w - $c1, $hc2 = $h - $c2

    If (($wc1 > 1 And $wc1 < $w) Or ($w - @DesktopWidth > 1) Or ($hc2 > 7 And $hc2 < $h) Or ($h - @DesktopHeight > 1)) And (BitAND(WinGetState(HWnd($hWnd)), 32) = 32) Then
        Local $hBmp_t = _GDIPlus_BitmapCreateFromHBITMAP($hHBitmap)
        $hBmp = _GDIPlus_BitmapCloneArea($hBmp_t, 8, 8, $w - 16, $h - 16)
        _GDIPlus_BitmapDispose($hBmp_t)
    Else
        $hBmp = _GDIPlus_BitmapCreateFromHBITMAP($hHBitmap)
    EndIf
    _WinAPI_DeleteObject($hHBitmap)
    Return $hBmp
EndFunc   ;==>Capture_Window

The captured window might be looking different than the original window. This is a problem with the PrintWindow function!

Br,

UEZ

[Schoening]

It works! Sir you are a gentlemen and a scholar!

Thanks to both of you. It all works perfectly now

[tntaien]

Apologies for refreshing the topic, but with windows 7 x64 ,  sometimes it will capture the screen successfully, and sometimes it's just a black screen.  However when i test it with a static window like mspaint, it is 100%.   Is there anything i can do to ensure the non-static window can capture it successfully? for example freeze the window during a capture perhaps?  Or is there anything i can look into to test around? Thanks.

[UEZ]

On same window or on different windows? If different windows then what kind of appl. are you trying? Video? Games?

[tntaien]

sorry for getting back late.  i would be lying if i said it wasn't for a game.  Yes, i know it's against the rules.  but if you wanted to know it's for bluestacks, however it's more for the reward of solving a problem.  but thanks for what you posted it could be useful someday. 

Edited May 31, 2015 by tntaien

[Jos]

sorry for getting back late.  i would be lying if i said it wasn't for a game.  Yes, i know it's against the rules.  but if you wanted to know it's for bluestacks, however it's more for the reward of solving a problem.  but thanks for what you posted it could be useful someday.  

​You better think before posting one more post on this topic. Our rules are crystal clear and since you knew already you are posting on a topic hat isn't allowed, you've use up all your credits.

Jos
 

Edited May 30, 2015 by Jos

[tntaien]

ok thanks for warning.  I'll edit the post so it doesn't contain any info on the topic.  

[Jos]

ok thanks for warning.  I'll edit the post so it doesn't contain any info on the topic.  

​The Forum rules are also pretty clear about this.

Jos