Deinterlacing refers to the technique which demands the display to
buffer one or more fields and recombine them into full frames. Theoretically,
this technique sound as simple as capturing one field and combining it with the
next field to be received and then producing a single frame. However,
deinterlacing is far more form simple in actual application. Generally
speaking, the originally recorded signal was produced as a series of fields.
What’s more, any motion of the objects during the short period between the
fields will be encoded into the display. As a result, even the slightest
differences between the two field due to the motion of the objects may lead to
a “combing” effect in the combination process of a single frame. Therefore,
deinterlacing is a very demanding technique requiring people to be careful and
patient.
Actually, there are a variety of methods for people to choose from
in terms of deinterlacing video. In addition, each method will cause different
problems or artifacts of its own. On the other hand, some methods are much
cleaner in artifacts than other methods.
Most deinterlacing techniques can be divided into three different
groups which use their own exact techniques. The first group is called field
combination deinterlacers. The name comes from the fact that they are able to
take the even and odd fields and combine them into frame displayed later. The
second group is called field extension deinterlacers for each field is extended
to the entire screen in order to make a frame. The third group is called motion
compensation which uses a combination of both.
Modern deinterlacing systems are able to buffer several fields and
use techniques like edge detection in order to locate the motion between the
fields. Therefore, this is adopted by people to interpolate the missing lines
from the original field and reducing the combining effect.
