In television, one half of horizontal pixels rows are refreshed in one cycle and the other half in the next cycle. This process is known as ______.

Question

Question

This question was previously asked in

RRB ALP Mechanic Radio & TV 23 Jan 2019 Official Paper (Shift 3)

Answer 1

The correct option is 3

Concept:

In Interlaced Scanning, the screen is refreshed in two cycles. During the first cycle, all the odd-numbered lines (or horizontal pixel rows) are drawn on the screen, and during the next cycle, all the even-numbered lines are drawn. These cycles are so fast that our eyes perceive them as continuous motion.
The advantage of interlaced scanning over progressive (where every line is refreshed sequentially during each cycle) is that it provides smoother motion in video with a lower bandwidth or data usage because you're effectively only refreshing half the screen at a time.
Also, interlaced scanning was particularly useful in the days of older analogue television broadcasts in maintaining a high image quality without needing a high transmission bandwidth. However, for static images or slow-motion videos, it can cause a visible "combing" or "feathering" effect.
The ‘interlaced scanning’ is shown in the figure below:

F1 S.B Deepak 28.12.2019 D1