Tone-Dialer Decoder

This idea has sprung from my Miniature Tone Dialer idea (see link). As [imaginality] said there, how do you know what number is on that strange tone-dialer? This device reads those beeps and decodes them into the numbers they represent. This idea isn't commercailly baked, so it would be helpful (some people can distinguish the difference between the beeps, but this is faster for most people.) Not only would this help with the odd spam tone-dialer, it could be used for more practical purposes. For example, telling the difference between a beeping tone-dialer and a beeping bomb (it could be both: see first link again.) Number-based codes just got better with this! One person inputs the code in a mini tone-dialer and the other uses this to turn it back into a workable code again. Auto-solver functions available for police units everywhere, but all additional settings extra.