Question

I have made some c code for a program, which does some psycho-acoustics on sound data.

There is a piece of code which runs very slowly.

I think it would be best to use a look up table. How would one go about implementing it?

Any pointers or help would be appreciated! 🙂

Answer 1

Your values are not equidistant so it is not that easy. But its still possible: take your greatest common divisor of all your condition-values (thats here 50) and then make your table

byteout = lut[difference/50 + 12];

And in the lookup table you can just use your values in the posted order, where you duplicate the entries in case your stepping is 100.

Btw it just see, there is a mistake, all your negative cases are catched by your first <=0 (my example assumes that you want to omit the first case).