It is possible to go from Chinese to Pinyin (not necessarily 100% accurate), but from Pinyin to Chinese, it is impossible unless you have a dictionary.
For example:jinan，计算机怎么知道是济南还是暨南还是晋安?

Unless you have a dictionary mapping the following relationship:

[{ "pinyin":"shandong", "chinese":"山东" },{ "pinyin":"jinan", "chinese":"济南" }}

Why?
Because Chinese culture is broad and profound.