Deinterlacing refers to the technique of converting interlaced
video. For example, when you are converting the common analog television
signals or 1080i format signal into a non-interlaced form, you are performing
the process of deinterlacing by your own. Generally speaking, interlaced video
can be directly displayed on ALiS plasma panels and the old CRTs. However,
modern computer video displays and TV sets are mostly based on LCD technology,
the majority of which adopt progressive scanning. Therefore, interlaced video
can not be directly displayed on such modern computer video displays and TV
sets. Under this circumstance, the technique of deinterlacing is of great
necessity and value in our daily life. The process of deinterlacing plays a
vital role for people to display interlaced video on a progressive scan
display.
As a matter of fact, interlaced video is made up of two sub-fields
which are taken in sequence. Generally speaking, each of the two sub-fields is
sequentially scanned at odd and even lines of the image sensor separately. This
technique is adopted by the analog television because less transmission
bandwidth is allowed for and the perceived flicker can be eliminated to a
greater degree. Displays based on CRT were able to correctly display interlaced
video because of its complete analog nature. On the other hand, all of the
modern displays are designed to be digital in nature because the display
consists of discrete pixels. As a result, the two fields need to be combined
into a single frame, which will lead to a variety of visual defects. The
technique of deinterlacing should try to avoid such conditions as much as
possible.
People have been dedicated to improving the technique of
deinterlacing for decades. What’s more, complex processing algorithms have been
adopted as well. Unfortunately, it is rather difficult to achieve consistent
results. However, we should have confidence in technologists and the more and
more developed science and technology. The technique of deinterlacing will be
improved step by step.
