In The Records of the Grand Historian, or Shiji, a historical account of the period 109-91 BC by Sima Qian, Confucius is described as having an unusual look - with a head that was somewhat depressed in the center and raised on the sides.

Shiji also describes the adult Confucius as being about 1.9m tall in today's measurements, giving him the height of an average basketball player. The book also cites someone who ran into Confucius as saying he was "tall and slim, with a pale green complexion."

In Kongcongzi, a book written around 2,000 years ago, Confucius had a slight hunchback and long arms.

Zhuangzi, a classic on Taosim, mentions Confucius' upper body as longer than the lower one.

Most portraits of Confucius seen today are based on the depiction by Wu Daozi, a painter of the Tang Dynasty (AD 618-907). The philosopher is shown as a tall old man sporting a long beard. He looks learned and amiable.

In September 2006, the Confucius Federation released a "standard portrait of Confucius". While still based on the painting by Wu Daozi, the philosopher is portrayed as a gentle old man in a robe, with a square face, broad mouth, big ears and long beard.

It created quite a stir. Some slammed it saying every one has his or her own conception of Confucius and the idea of a "standard portrait" is meaningless.

Some felt the federation was just out to make money as it claimed the portrait's copyright and reportedly said it would charge those who made use of the image.

Whether or not Chow makes a convincing Confucius remains to be seen, but director Hu is ready for all reactions.

"It is impossible to avoid controversy when you are making a film abut Confucius," she says. "This is the first film about Confucius, making it a double-edged sword. On the one hand, no one is totally confident criticizing my choice as none of them has seen Confucius; on the other, everybody is deeply concerned about this film, which is kind of stressful."