Progressive Scan vs. Interlaced Scan
First, I want to inform you that the meaning of ‘P’ after any display resolution (like 1080p or 720p or
1440p, or 2160p) is not ‘Pixel’,. The meaning of ‘P’ is ‘Progressive’. And there is also another like that, which is called ‘i’(1080i) i.e. ‘Interlaced’
On other hand, a television screen updates
each field of a video frame separately. For this reason, the television has to update its
display twice to show a complete frame. The first time, it updates the odd fields, and after 1/60th of a second, it updates the even fields. It continues alternating between the odd and lines 60 times in a second. A television displays content at 60 frames per second. This is called an interlaced display.
L.C.D. T.V. that is coming with a
progressive scanning display in the market. Because the progressive scanning
display creates much more clarity than the interlaced scanning display. But here
is a drawback, you have to reduce the resolution for the quality.
we process the interlaced signal to a progressive signal there occurs an
annoying situation that is called ‘Combing’. Combing is created when
each individual frame transfers from interlaced to progressive which is done by
your Digital SetTop box or the T.V. itself. This combing only happens when you
watch T.V. with a Progressive screen or on a computer monitor via a T.V. tuner.
processes. Let’s discuss it below.
The motion appears smoother and more realistic.
There are no interlace artefacts in
the frames and can be captured for use as still photos.
movies and video games, there is always used a
progressive scanning process.
It also offers clearer and
faster results for scaling higher resolutions than its
equivalent interlaced video, such as upconverting 480p video to display
on a 1080p
The most important factors in analogue
television are signal bandwidth, which is measured in megahertz (Mhz). The
greater the bandwidth, the more expensive and complex it will be. This
includes cameras, storage devices, broadcast and reception systems i.e. the terrestrial,
cable, satellite, Internet, and end-user displays (TVs and computer monitors).
The interlaced video can also provide a higher resolution than a progressive scan if we give a fixed bandwidth and high refresh rate. For example, 1920×1080 pixel resolution interlaced
HDTV with a 60 Hz refresh rate (i.e. known as 1080i 60Hz) has a
similar bandwidth with 1280×720 pixel progressive scan TV with a 60 Hz frame
rate (i.e. 720p 60Hz), but it achieves approximately twice the spatial
resolution in terms of slow-motion scenes.
Interlacing can be used to produce
3D TV cinema, especially with a CRT display, and more especially, for colour-filtered glasses by transmitting the colour-keyed picture for each eye in the
alternating fields. There is not any requirement for significant alterations to
existing equipment. We can use shutter glasses, certainly with the requirement
of achieving synchronization. When we try to use a progressive scan display to view this type of programming and also try to deinterlace, then the rendered picture becomes useless.