Video Resolution

Video Resolution:

We have heard about 240p, 480p, 720p, 1080p etc resolution for monitors, TV or mobile screens. What is the meaning of it?

These are all video resolutions which denote the vertical resolution. This denotes the number of vertical lines drawn in each frame. For example, 720p means that 720 lines are drawn in each frame.
There are two types of video broadcasting formats: progressive (p) and interlaced (i). The difference between the two is in the number of columns of pixels taken up in displaying the video (interlaced video takes information from alternate columns).

Most Common Video Resolutions are the following ones:

•     352 x 240 (240p) (SD)
•     480 x 360 (360p)
•     858 x 480 (480p)
•     1280 x 720 (720p) (Half HD)
•     1920 x 1080 (1080p) (Full HD)
•     3860 x 2160 (2160p) (Ultra-HD) (4K)

How to calculate number of pixels based on vertical resolution?

For digital video, you can multiply the vertical lines with aspect ratio to calculate the number of pixels to be placed in each vertical line. This gives the number of pixels placed in one vertical line. Multiplication of (Total number of pixels in one vertical line) x (Number of vertical lines) = gives total number of pixels.

For example, 720p display will contain 720 vertical lines. the number of pixels present in each vertical line is calculated by 720*(16/9) = 1280 pixels where 16:9 is the aspect ratio.
The same can be achieved for 1080p where 1080*(16/9) = 1920 pixels.