Reading Photos.

Hi guys!

Iam new here! Iam a student of computer Graphics and I have some questions about one work I have to do.
It's suppose I have some photos of QR codes and I have to translate the content of that code.
I have been looking in some web pages and it sais that I have to convert my photo to grey scale and then apply some segmentation method.
For example the next:

• Edge detection methods
• Thresholding based methods
• Region based methods
• Cluster based methods
• Graph based methods

But I dont know which will be better... Do U have some idea?

Thank u very much!