Cannot get bitmaps of screen from Gdip

[SuperMrTheGuy1]

I am having difficulty using Gdip to get bitmaps of windows given a window handle. I have tried using a basic script that was actually provided by another user on this forum, as seen from the link below, but the Gdip_BitmapFromScreen() returns nothing.

https://autohotkey.com/board/topic/9142 ... of-screen/

This is the code that I have tried, pToken is 928019671, and the bitmap is blank and does not save a bitmap to disk.

If you could help me at all, thanks!

F1::
pToken := Gdip_Startup()
pBitmap := Gdip_BitmapFromScreen()
Gdip_SaveBitmapToFile(pBitmap, "Image.png")
Gdip_DisposeImage(pBitmap)
Gdip_Shutdown(pToken)
msgbox %pToken% %pBitmap%
Return

[JoeWinograd]

The code you posted works perfectly here – creates a file called Image.png in the folder where the script is. Have you included the Gdip code in your script or an #Include statement for it?

[SuperMrTheGuy1]

I have included the Gdip.ahk file in my code, i have this line in it:

#include Gdip.ahk ; download form http://www.autohotkey.com/forum/topic32238.html

Also the Gdip.ahk is in the same directory as the script is running from.

[SuperMrTheGuy1]

I have included the Gdip.ahk in my script, using the following line which is near the beginning of the script:

#include Gdip.ahk ; download form http://www.autohotkey.com/forum/topic32238.html

I have also created a file called Gdip.ahk in the same directory as the script which includes the Gdip download.

[JoeWinograd]

Are you using the code at this link:
http://www.autohotkey.net/~tic/Gdip.ahk

That's what I'm using and the script you posted works perfectly with it (AHK 1.1.25.01/U32). The first troubleshooting step I would take is to put in a simple MsgBox command after each of your first three Gdip function calls to show what the functions are returning. My guess is that the Gdip_SaveBitmapToFile call is returning something other than zero — the error values (-1 through -5) are documented in the Gdip source.

[SuperMrTheGuy1]

I have changed the code so that it is the following code at the end, and still am having issues.

The ptoken value is 949203328, which I assume is ok.

pBitmap returns 0, which from reading the man pages I think is a pointer to a bitmap image, which worries me that it is 0.

Then SavebitmapToFile fails and the error code is -3, which is "Could not find matching encoder for specified file format".

I am unsure of how to proceed from this point, could I be missing additional drivers necessary?

#include Gdip.ahk ; download form http://www.autohotkey.com/forum/topic32238.html

F1::
pToken := Gdip_Startup()
msgbox ptoken %pToken%
pBitmap := Gdip_BitmapFromScreen()
msgbox pBitmap %pBitmap%
statusofsave := Gdip_SaveBitmapToFile(pBitmap, "Image.bmp")
msgbox save status %statusofsave%
Gdip_DisposeImage(pBitmap)
Gdip_Shutdown(pToken)

Return

[just me]

Are you running AHK x64? The original Gdip lib is not completely x64 compatible.

[SuperMrTheGuy1]

That fixed it! I was using x64 installation and not x32 installation. Wasted about 10 hours on this thank you so much!

[JoeWinograd]

Great catch, just me!

[ed1chandler]

Ugh, wasted a few hours on that myself. It worked perfectly while debugging in Scite (which apparently uses the 32-bit version), but wouldn't do squat when I just double-clicked the script.

My solution (and someone please tell me a better one) is to change the extension of scripts requiring the 32-bit version to ".ahk32" and then associate that extension with AutohotkeyU32.exe.

THANK YOU for pointing this out.

[iseahound]

Use Gdip_All which is 32 and 64 bit compatible.