Hi.
Now i'm applying for return resident paper, it require 3 different photographs.

according to the application form, the requirement for photograph is as following: "recent photographs showing a full front view of the head and shoulders, without head covering,taken against a plain white background. each photograph must be on single weight unglazed(mattle finish) paper and is to measure no more than 1-1/2 *1-3/4 inches(38*44 mm)"

My questions are:
1. what "against plain white background" mean? my understanding is it's not color photograph, but black and white photo. Is that right?
2.what "unglazed paper" mean. can anybody explain it in chinese?

Any help is tremendously appreciated.