by Matt Smith
Television manufacturers can be a tricky bunch. Just when you think you've figured out their acronyms and slang, things change again. In the early days of HDTV people were scrambling to figure out the difference between 1080i and 1080p and manufacturers were playing sly with acronyms by sticking the EDTV (Enhanced Definition Television) acronym on sets without explaining how it differed from HD.
As the market for HDTVs matured, the manufacturers settled down and organizations began to develop standards, but the terms are still sometimes confusing. "HD Ready" and "Full HD" are short-hand definitions often attached to sets, but the difference between them isn't always clear to the layman. Read on if you still find the picture to be a bit fuzzy.
HD Ready - In The United States
The term HD Ready was used in the United States to note a display that had the ability to display a high-definition picture (720p, 1080i or 1080p) but did not have a built-in HD tuner.
In other words, the display worked like a monitor. It had to be connected to a set-top box or other high-definition content device that could drive a signal to it. A full HDTV was different because it had a built-in HD tuner that could receive HD over-the-air transmissions.
The term HD Ready became obsolete in the United States due to FCC mandates that forced television manufacturers to include a digital tuner. The mandate went into effect for all televisions sold after March 1st, 2007.
HD Ready - In Europe
The term HD Ready is different in Europe. In 2005 an industry association known as EICTA (and since re-named DIGITALEUROPE) set down a standard for the term HD Ready. For a television to qualify as HD Ready it needs to be capable of 720 horizontal lines of resolution. It also must accept certain inputs such as HDMI or DVI with copy protection (HDCP).
There's also a standard called HD Ready 1080p. This standard demands that a television have native resolution of 1920×1080. It also must be able to display 1080p and 1080i video sources without overscan (in other words, the image as displayed is exactly 1920×1080) and must be able to reproduce video formats without distortion.
As in the United States prior to the FFC mandate, an HD Ready television may not include a digital tuner and will require a separate tuner device to function.
An additional HD TV / HD TV 1080p standard has been created by DIGITALEUROPE to represent a television that has a built-in ability to decode HD television signals and display them in compliance with the HD Ready / HD Ready 1080p standard.
This is still a relevant difference because only some European countries have mandated digital tuners in all televisions.
Full HD
The term Full HD is often used in marketing materials across the globe. It is not, however, a standard that has been adopted by any government agency or trade organization. Full HD is used as a synonym for 1080p as a means of up-selling consumers looking at HD Ready sets.
1080p televisions have a resolution of 1920×1080 and are progressive scan, which means all lines of each frame of video are drawn on the set. This marks 1080p as different 1080 interlaced (1080i) which alternates between rendering only the horizontal and vertical lines of each frame.
Since Full HD is only a marketing term, it does not indicate any particular qualities besides 1080p. A set labeled as Full HD may not be capable of 1-to-1 pixel mapping or might not be able to properly display all 1080p video sources. You'll need to refer to manufacturer spec sheets and independent reviews to be sure.
Does It Matter?
Now that you know what the terms mean, we are forced to return to an age old debate. Does 1080p (aka Full HD) matter?
The answer is - it depends. The only thing that can be said about a set with 720p (a.k.a. HD Ready) resolution is that it has fewer pixels than a set that features 1080p (aka Full HD). The terms say nothing about overall image quality, color accuracy, the black levels and concerns that have a significant impact on image quality.
A 720p display may appear less sharp than a 1080p display. The difference will become more noticeable as physical display size increases and the distance between the viewer's eyes and the set decreases. A viewer with 20/20 vision sitting six feet away from a 51" television will likely see a difference. The same person sitting ten feet away may no longer notice it.
While display resolution does not directly indicate overall image quality it's worth noting that most manufacturers only sell 720p sets only as budget models. As a result, a 720p set probably won't have world-beating image quality.
Conclusion
I do not have knowledge of other parts of the world such as Asia and Africa. If there are standards in your country that don't agree with what's listed here, feel free to post them in a comment. I am sure other readers will find them helpful.
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