Searching For An Image In An Image / Image Comparison / API Call

[ss7thirty]

I was wondering what the best way to go about this was. I am going to be taking a screenshot of a piece of the screen. What I want to do is find out a good way to select a section of a window (outside of my application) and compare that selection to a larger image and see where on the image that piece is. This may be very hard but I need to figure out how to do this.

I don't have much yet because the other part of the application have been time consuming but I will continue to research the necesary API calls. But the 2.0 framework has a lot more in the Drawing namespace and I think that I should easily be able to take a piece of the screen and compare it to another image.

 

[JohnH]

Maybe if you explained what you are doing someone could think of a better way to do it? One example of difficulty is if you copy part of an image it will often change slightly due to graphics settings and possibly compression, so while it looks the same it is not possible to get a match.

 

[ss7thirty]

Sorry, I will try to explain further. You have been beyond helpful thus far and it is greatly appreciated.

I am going to have a bmp screenshot file. I will also have a folder of bmp screenshots taken using the same script using the same software. I want to take the bmp screenshot and compare it to the ones in the file structure and based on the match carry out the necessary tasks.

 

[JohnH]

If you're looking for unique screenshots, ie discarding identical shots, just compare the file sizes.

 

[ss7thirty]

I was thinking about that...It would be highly unlikely that two screenshots would have the exact same ammount of bytes I guess.