Photoshop script odd number

Question

I need to open an image and check that the width and height are even numbers. If they are not -1px.

How do I check to see if a number is odd?

291px would = 290px

333px would = 332px

121px would = 120px

Answer 1

Untested, but you should be able to do this:

if(x&1) {x--}

That tests if the least significant bit is one (i.e. x is odd) and decrements it if so.