Video is a type of electronic signal that encodes and decodes images and sound. It is most commonly used to refer to the display of moving pictures on a screen, as in a movie or television program. Video can also be recorded on tape or other storage devices, and viewed later.
The word video comes from the Latin word for “I see.” The first recorded use of the term was in an article published in Scientific American in 1878. In the early days of electronics, scientists and engineers used the term to mean any kind of electrical signal that could be displayed on a screen. Today, video generally refers to digital signals that are used to create moving images.
There are two main types of digital video: interlaced and progressive scan. Interlaced scanning draws every other line on the screen, then goes back and draws the lines in between. Progressive scanning draws all of the lines on the screen at once. Most televisions use interlaced scanning, while most computers use progressive scanning.
When you take a picture with a digital camera, what you’re really doing is capturing a series of still images very rapidly—typically about 30 frames per second (fps). These images are called frames, and when they’re played back in rapid succession, they give the illusion of motion. The number of frames per second is known as the frame rate; movies are typically shot at 24 fps, while television programs are usually shot at 30 fps or 60 fps (in North America) or 50 fps (in Europe). Higher frame rates can make videos look smoother but can also require more bandwidth and processing power.
The resolution of a video signal is measured in pixels—the tiny dots that make up an image on a screen. A standard-definition television has a resolution of 480i (or 480 interlaced), which means that it displays 480 horizontal lines each composed of 525 individual pixels; when these lines are drawn progressively (480p), there are only 483 active pixel rows because each new line alternates with an existing one from previous fields. High-definition television systems have resolutions ranging from 720p (1280×720 progressive) to 1080i/1080p (1920×1080 interlaced/progressive). Ultra-high-definition television has resolutions up to 8K (7680×4320), although these systems are not yet commercially available. 4K Resolution refers to 4096×2160 – more than twice as many pixels horizontally as 1080 HDTVs!
5K Resolution refers to 5120×2880 – five times as many pixels as 1080 HDTVs! 6K Resolution refers to 6144×3456 – six times as many pixels as 1080 HDTVs![citation needed]Reduced Blur Motion artifacts caused by camera shake blur objects both during capture phase due exposure time shutter speed being too long combined high speeds movement being photographed resulting slight blurring around edges objects well background.[citation needed] Frame Rate Manipulation speeding film often done increase sense urgency drama comedies need comic relief contrast intense scenes action thrillers result shorter exposures less blurring increased sharpness image however sacrificing quality smoothness motion playback process may cause jerkiness flickering artifacts depending how big factor rate increased some cases extreme slowmotion effect achieved using highspeed cameras filming subjects extremely fast speeds then played back normal providing amazing detail otherwise imperceptible human eye such water droplets falling raindrops shattering glass etcetera.”