I picked first US patent listed (US 7,292,636), and it's first claim says > 1. For a bitstream comprising a first video picture, a second video picture, and a

I picked first US patent listed (US 7,292,636), and it's first claim says > 1. For a bitstream comprising a first video picture, a second video picture, and a third video picture, a method of decoding comprising: computing a particular value that is based on (i) a first order difference value between an order value for the third video picture and an order value for the first video picture, and (ii) a second order difference value between an order value for the second video picture and the order value for the first video picture; computing a particular motion vector for the second video picture based on the particular value and a motion vector for the third video picture; and decoding at least one video picture by using the computed motion vector. That certainly sounds like math to me.