The earliest known form of video compression was the use of the interlaced format, developed roughly 70 years ago to address early TV technology challenges and broadcast bandwidth constraints. In interlaced video, each field of a video image displays every other horizontal line of the complete image. For example, in the first interlaced field, the even-numbered lines making up the complete image would be displayed, and then with the second field, the odd-number lines of that image would be shown.
The main benefit of interlaced video is that it allows more detailed images to be created than would otherwise be possible within a given amount of bandwidth — in effect, interlacing allows a doubling of image resolution. But interlaced video comes with real-world downside, including image softening that occurs during fast-motion sequences as well as moire or strobing artifacts that sometimes appear when striped shirts, plaid jackets, bricks in a building, or similar types of objects are shown.
Progressive video, on the other hand, is made up of consecutively displayed video frames that contain all of the horizontal lines that make up the image being shown. As a result, images appear smoother, fast-motion sequences are sharper and artifacts are much less prevalent. The primary drawback to progressive video, at least until very recently, was the higher bandwidth requirement.
But today, television systems and packaged media such as DVD are moving away from analog transmission and storage to digital variants, allowing considerably more efficient video compression to be applied.
This results in even higher resolution images than were possible via interlaced analog video, using the same amount of bandwidth. While interlaced video will continue to be with us for some time as a result of the 1,line interlaced i HD format used by broadcasters in the US and some other countries, both displays and packaged media are moving exclusively toward progressive video formats, such as and line progressive p and p formats.
Progressive has become the standard because of its better video compression abilities, and higher quality images. Your content goes here. You must have noticed that a video resolution is followed by a letter "i" or "p", such as i and p.
What do the letters mean? Actually, i stands for interlaced scan while p is short for progressive scan. They are two different kinds of scanning types. What is interlaced scanning? What is progressive scanning? Here we'll explain them and compare them. Interlaced Scan is an old technology. In interlaced scan, every frame in a video is divided into a number of horizontal scan lines. For example, every frame in i video will be divided into horizontal scan lines.
Then, it will split those lines into groups of odd lines and even lines. A complete frame is displayed in two times. So this is interlaced scan. It is used to help display traditional analog TV broadcasts on a TV screen.
In contrast to interlaced scan, progressive scan aka. This is a more modern display technology. The difference between interlaced scan and progressive scan involves how they display a frame. Interlaced video divides a frame into even filed and odd filed to display while progressive video displays the entire frame at once.
Interlacing provides full vertical detail with the same bandwidth that would be required for a full progressive scan, but with twice the perceived frame rate and refresh rate.
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