How reliable is PixelChecksum ?

[JohnOne]

I ask because, I have ran it on a seemingly Identical region of the screen but produced two different checksums.

The region is quite small 12x2 pixels, would this cause unreliability ?

I captured the exact region of checksum using Screencapture_Capture, and examined them as many times as my eyes will allow.

Autoit windows info tool reports each pixel as the same colour, in both images.

Has anyone encountered this, I would appreciate your insight.

[Richard Robertson]

The checksum may involve the location of the pixels. Pixel checksums aren't meant to compare to regions of the screen. They are meant to watch a region of the screen to see if it has changed.

[JohnOne]

Yes, it was a bit strange.

My script was meant to look at an area on the screen, perform a checksum of it, and then save a screencapture of it and save to file, with its pixelchecksum return being the name of the file.

It performs this function at given intervals, and only saves a new file if the checksum has changed.

I found 2 files with different names, compared them to find the differenc and they where the same.

I can only assume picelchecksum detected a change, but by the time screencapture got it the change was gone.

I have to assume this, if just for my sanitys sake.

Thanks for your reply.