Pinyin is not a proper alternative as written Chinese characters, like Bramiozo and Rubber Duck pointed out, it is ambiguous and has the one to many conversion difficulties. (Both of whom I admired with so much knowledge being non-Chinese natives).
To demonstrate their points, take the example of the name Mao Xiaofei, who wrote earlier.
MAO can be any of the following in writing (just to name a few):
毛-hair, 帽-hat, 猫-cat, 茂-flourish, 贸-trade, 茅-spear, 描-copy
XIAO can be the following:
小-little, 笑-laugh, 消-cancel, 宵-night, 晓-morning, 箫-flute, �*�-college
FEI can be the following:
非-not, 飞-fly, 肥-fat, 匪-bandit, 肺-lung, 废-discard, 妃-Concubine
Like 宵 and 晓, are completely opposite, but both pronounced xiao, straightly speaking, xiao1 and xiao2.
To guess what his name is, the surname is 毛, because it is the most common one, but I may be wrong, as 茂 and 描 are both rare but existing surnames in minority tribes.
His name should be 小飞, means little flyer, a popular name to imply who will go far. If you say he is 笑匪, a laughing bandit, both his parents must be mad. (just joking)
But mind you this could be meaningful if not used in a name, like 消肥, reduce fat, slimming, also pronounced xiao fei.
One can only make intelligent guess according to the context and in no way I know 毛小飞 is correct, because 描晓飞 could be very possible, for morning or early take off.
There are so many combinations in the 7x7x7 example above, but picking one on each word, the pinyin is only one: Mao Xiao Fei. You see the problem? Almost irreversible.
No Chinese reads writings in pinyin, they read IDN characters. To give a page typed in pinyin to the translator, he won't do it unless you pay him 7 times more.
Since so many are interested in Chinese IDNs, the following are 2 more useful translation site links.
http://www.lexiconer.com/ecresult.php http://www.lexiconer.com/ceresult.php
Please note in the above thread, 檡-college is wrong, it is �*�-college.
While 消肥 can mean reduce fat, don't try to register this as IDN, the proper phrase is 消脂-burn out the grease, or 减肥-slimming, both of them registered already.
(�*�-college)
Still wrong! A bug in DNForum character set!
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