Watching TV is a past-time that a lot of people and has been around for a very long time. For some the recent introduction of HDTV has brought a new era to TV viewing. In fact some consumer reports have suggested that since the introduction of HD Televisions, more consumers have purchased and began watching TV.
Originally used on analogue platforms, HDTV was able to produce picture resolutions of up to 480p or 480 lines progressively. There were some TVs that were capable of producing up to 576p which at the time was considered true HD. Most HD Televisions use progressive scan technology to process picture resolutions, it is also known P-Scan.
A brief history
P-Scan or progressive scan has been used for a number of picture displays including all LCD (Liquid Crystal Display) monitors, most CRT (Cathode Ray Tube) monitors and most HDTVs. Other types of displays including SD (standard definition) TVs use interlaced scanning technology.
Major Differences between Interlaced & Progressive Scanning:
Both interlaced scanning and progressive scanning use different methods to scan and reproduce pictures and images on the HDTVs. This is often identified by the letters I for Interlaced Scanning and p for Progressive Scanning. For example 1080i and 1080p, although having similar resolutions, the actual quality of the picture resolution will be different because of a number of things that make the two scanning technologies different.
Interlaced scanning was used with most analogue and standard definition TVs that were based on the CRT platform. Although the benefits of interlaced scanning may appear to be more attractive, there are a number of disadvantages and reasons why the technology has not being adapted worldwide. Most HDTVs support progressive scanning, there are few that support interlaced scanning. Most film production companies produce their content in 24p. It is easier to use progressive scanning because it makes reproduction of recorded content easier as compared to interlaced scanning which needs to be displayed on a deinterlacing display.
Also interlaced scanning requires that video is uncompressed whereas most digital broadcasting and technology compresses video to maintain and fit to bandwidth requirements. DVDs use progressive scanning.
Most HD TVs use progressive scanning and are able to display top quality images but for those with a desire to experience uncompressed video, interlaced HDTV displays are available and these two can display both progressive and interlaced content. The main reason interlaced HDTVs are not mainstream is because of the technologies that have been adopted by major media companies.
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