Here are some suggestions: Whatever method you try, look at a large number of dirty floor samples to get an idea of the range of things - is it a darker area, is it streaks, etc. For a simple idea, ...

Assuming you are talking about a cryptographic hash (as opposed to a hash used for speeding lookups, say), I think you are posing contradictory requirements. The purpose of a hash is to remove any ...

The formula says that the resized (smaller) image pixel at (x,y) is a bilinear approximation of the pixel at location (2ax+b, 2ay+b). Ignoring b for the moment, you can see that the scale factor (or &...

Assuming that the filter is a linear FIR filter and you know (or choose) the size of the filter, this can be solved the following way. We have a known image f and an output image g, and we want to ...

You said fastest way, I assume you mean calculation operations, as opposed to code run time - not sure if there is an optimized routine for the algorithm I describe. You can use row reduction (...