Compare Images with ImageMagick

[CableGuy]

Hi,

I want to compare 2 images i get from _ScreenCapture_Capture(). I search a while and read a lot about ImageMagick and i think i figured out 2 ways i can do this.

The first way could be an DllCall. The other way is the COM-Object.

First i tried the DllCall but this is not working. I´m always get an Error 1. I think there something wrong with my parameters.

Local $result = DllCall($dll, "double", "MagickCompareImages","metric","PSNR","uint",$hReference,"uint",$hImage)

COM-Object could work but it seems that he´s not accepting the variable which contains the HBITMAP returned from

ScreenCapture_Capture(). I also tried to use _GDIPlus_BitmapCreateFromHBITMAP() for this variable, with no luck. He always returns

me "The requested action with this object has failed."

$oCompareObject = ObjCreate("ImageMagickObject.MagickImage")

    $result = $oCompareObject.Compare("-metric", "PSNR", _
            $hReference, _
            $hImage, _
            "null:")

Could anyone help me to fix this problem ?

Thanks in advance

[jftuga]

If you can't find an AutoIt solution, I solved this problem some time ago with another program.

Here is the info:

https://github.com/jftuga/Misc/tree/master/Finding_the_differences_between_two_similar_images

-John

[CableGuy]

Thanks for your reply!

Calling an exe could be a solution but it is too slow for my program.

Any other ideas ?

[water]

What do you want to achieve? Compare the images and check if they are equal? Or get the areas where the picture has changed?

[CableGuy]

I want to check if two pictures are equal. And if they are not equal i want to get an percentages or something else for the difference between the two pictures.

Thank you

[water]

I see.

Can you please tell us what you try to achieve? I mean, why do you need to compare two screenshots?

[CableGuy]

i want detect changes made on my desktop. if the images are equal it´s not necessary to save the screenshot again.

[water]

Changes on the desktop means: New, deleted or moved icons. Anything else? Wouldn't it be easier to monitor the icons?

[CableGuy]

i´m also want to see if someone is working on my pc, starting programs, browse my files and so on....

[water]

I would lock the PC so noone can work there

But I think it is easier to check for Mouse moves, new tasks etc.

[CableGuy]

Thanks for your suggestion.

But i would prefer to make screenshots so it´s easier to reproduce changes.

[CableGuy]

*bump*

[Rogue5099]

Although the intentions may be pure and for security, this could also lead to spyware.