HD in fact stands for High Definition. Well HD simply refers to an increase in display or also visual resolution over a previously used standard. High definition sometimes abbreviated as HD. There are quite a few terms that are associated with this high definition.

Let me here at first tell you about the high definition video.

High Definition Video

Well dear guys and girls here comes one of the concerning topic in the arena of high definition and that is high definition video. The fact about high definition video is that it is a video of higher resolution as well as quality than standard definition. There is no any standardized meaning for HD that is high definition here. And here generally any image in the video with considerably more than 480 horizontal lines or also 576 horizontal lines is considered as high-definition. Apart from this there are almost 480 scan lines that are generally the minimum even though the majority of systems greatly exceed that.

Also images of standard resolution captured at faster rate as compared to that of the normal one and this is  by a camera having rapid speed rate,  may be considered high-definition in some contexts. Well there are quite a few happenings behind this very topic that is high definition. Well let me share with you all the things regarding this topic so that you would be able to know all the points regarding this topic.

History

Well the first thing about HD video is that of electronic scanning format thing. The first electronic scanning format, 405 lines, was the first HD that is high definition television system, since the mechanical systems it replaced had far fewer. Well dear guys and girls in the year of 1939, Europe and the United States in fact tried 605 as well as 441 lines until, in 1941, the FCC mandated 525 for the United States. Let me here mentioned some of the facts about the HD definition in the following listed points.

• In the duration of 1990s, there is a process known as the FCC process, and this very process is in fact known by the ATSC. Here ATSC is an acronym that is used for Advanced television systems committee.
• Well the FCC process adopted a range of standards. And this very standard is from interlaced 1,080 line video with a maximum frame rate of 60 Hz and 720 line video, progressively scanned with a maximum frame rate of 60 Hz.
• However the DVB standard of resolutions and their respective frame rates were actually adopted in conjunction with the Europeans that were also involved in the same standardization process.
• Well dear guys in 2000s, especially in the early of 2000, it looked as if DVB would be the video standard far into the future.
• The fact is that not only Brazil but also China have adopted alternative standards for high definition video.

Therefore, these are some of the facts about high definition video.

Technical Details of HD Video

Given below are some of the things involved in the High Definition Video.

1. The first thing is the number of lines. And these number of lines are in the vertical display resolution. Here comes the HDTV that is high definition television. Well dear, these high definition television resolution is 1080 or 720 lines. As high definition is broadcast digitally, its introduction sometimes coincides with that of the DTV introduction. Also current DVD quality is not HD. The high definition disc systems Blu ray Disc and the HD DVD are.
2. So here is another one. There comes a system known as the scanning system. This includes progressive scanning or in other words also interlaced scanning. Well the first one is that of progressive one. So dear, the fact is that progressive scanning redraws an image frame when refreshing each image. On the another hand Interlaced scanning draws the image field every other line or you can say odd numbered lines during the very first image refresh operation. After then it draws the remaining ones. Or you can say it then draws even numbered lines  during the second refreshing. Also IS that is Interlaced Scanning yields greater image resolution if any subject is not moving.
3. Well in the third part, here includes the number of frames or fields per sec. In Europe the more common and widely used is 50 Hz television broadcasting on the another hand in the United States of America the same is 60 Hz television broadcasting system.

Thus dear guys these are three matter or in other words we can say that high definition video is defined in the above mentioned threefold. And the very HD video is prerecorded as well as broadcast.

HDTV

Now here comes the topic of HDTV. HDTV is actually high definition television. Now what happens in this HDTV? Well look dear, high definition television is a television system providing an image resolution. This is image resolution is of substantially higher resolution as compared o that of standard definition television. HDTV i.e higher definition television is the current standard video format used in most broadcasts. This includes following-

• Cable television
• Terrestrial broadcast television
• Satellite television
• DVDs
• Streaming video

Formats

There are various formats in which high definition television can be transmitted. Let me share with you below-

• The first one is 1080p,
• Secondly 1080i,
• And the last 720p.

It should be kept in mind that the term Full HD refers to 1080p.

The letter ‘p’ here indicates progressive scanning. On the other hand the letter ‘i’stands for interlaced. I have earlier focused about the very topic that is progressive scanning.

The another thing here is that when transmitted at two megapixels per frame, high definition television in fact provides about 5 times. Actually the transmission is about 5 times as many pixels as SD. Here SD refers to standard definition television. Thus dear the added resolution provides for a clearer as well as more detailed picture. Apart from this, progressive scan swaps the entire image out sixty times in addition, as compared to that of 30 times per sec of standard definition television. Therefore this leads to a picture without perceptible flicker.