It seems that everyone buying a new HDTV this year. Conversation around the water cooler is filled with techy buzzwords. If the HDTV standard in the United States by the ATSC (Advanced Television Systems Committee) was originally defined to eighteen different standard, but not all standards are in common use.
The standards, you need to know for HDTV (high definition television) are 720p, 1080i, 1080p, and in recent times. The number in the format(For example "720") is the vertical lines of screen resolution and the letter in the format (eg "p") is the display technology. The letter "p" stands for scanning "progressive", and the letter "i" means "interlaced".
HDTV
HDTV (either 720p, 1080i and 1080p) has a widescreen aspect ratio of 16:9 (width: height). EDTV (Enhanced Definition) is a standard definition TV (SDTV HDTV format first), but with some software "interpolation". HDTV offers a framework that isbetter than SDTV, but not as sharp as HDTV. EDTV uses progressive scanning. EDTV is sometimes an aspect ratio of 16:9 (widescreen).
As a reference, standard definition TV (SDTV, HDTV format first) 480 lines of vertical resolution and an aspect ratio of 4:3. The SDTV signal is the United States in the past has been an interlaced signal. This means that the TV draws each frame in two passes: once for the horizontal and a second passage for the oddLines. The specification has a maximum resolution for the technology, but often the sources of signal is less than the maximum. For example, VHS tape, approximately 240 lines of vertical resolution, over the air broadcast SDTV has about 330 lines of vertical resolution, a DVD and SDTV has about 480 lines of vertical resolution.
Televisions in Europe and Japan were (and are) progressive format. A progressive format makes a single pass for all lines.Progressive images look a bit 'smoother than an interlaced image, especially when there is a lot of movement on the screen, such as sports.
To add to the confusion, BluRay DVD, and at the end of this year, the company broadcast satellite TV to 1080p. This standard has both a greater number of lines of vertical resolution, and preferred progressive format. The satellite Dish Network starting in August 2008 1080p HDTV with 150 channels and DirecTV beginsSatellite and Internet transmission condense until the end of 2008 with about 130 channels HD programming. The satellite companies that sound with MPEG-4 technology, the bandwidth required for transmission reduced. Currently, the only source material for movies in 1080p, originally designed specifically for the IMAX film. None of the major networks (ABC, ESPN, etc.) have announced support for 1080p. In addition, Sony PlayStation 3 and Xbox 360 games have 1080p.
HDTVVideo formats: 720p, 1080i and 1080p is, the more better, right? Although technically the 1080th has a higher resolution, is not the obvious choice. 1080th has 1080 lines of vertical resolution and 1,920 horizontal lines of resolution. 720p has 720 lines of vertical resolution and has 1280 lines of horizontal resolution. But the system is subjected to 720p progressive scan. This compensates for the lower level of resolution. The 1080p signal is the best of both worlds, more image informationwith a progressive format.
If the signal is received, for example, a satellite receiver, is mainly standard definition, a 1080p TV will not improve significantly the image than a 720p TV. The picture quality is fundamentally different from the signal source (480 lines of vertical resolution) is limited. Similarly, if the signal source has a 720, then the 1080 TV will not improve your image. All high-definition sports broadcasts from Fox, ESPN and ABC are broadcast in 720p.
SomeNetworks have opted for the 1080i format, because it offers more image information, but ABC, Fox, ESPN and National Geographic Channel, smoother images have chosen to 720p. HDTV programming on CBS, NBC and other networks broadcast in 1080i . The new HDTVs 1080i or 1080p likely that this type of programming to make a little 'sharper than it appears on a TV 720p. This is particularly important because the TV screen is larger, the visible difference in detailbetween display 720p and 1080i and 1080p is not clear. For this reason, most HDTV sets larger than 50 inches have 1080p or 1080i.
1080p HDTV system functions:
A 1080p HDTV shows all inputs to 1080p, because that is the normal resolution of the device. If the system is less than 1080i or 1080p, then a special-purpose chip in your HDTV will scale the signal. It is interpolated, not as EDTV SDTV signal. If '1080i signal, the system combines the odd and even interlaced frames and display the full signal as 1080p. The resulting performance should be similar to a real video source to 1080p.
HDTV cable:
Over 100 million American households that can receive HDTV from cable network, and all 100 cable markets in the country have access to HDTV programming. Unfortunately, most cable providers only some of the 50 + available HDTVNetworks.
HDTV Satellite:
While the selection of local HDTV channels is generally better on cable and satellite, the satellite companies offer HDTV channels as major national and most cable providers. Both DirecTV and Dish Network have promised to offer more than 130 HD channels by year's end. "Satellite is not so much how many channels as they can from those who wear it can be limited to" Bob Scherman,Satellite Business News.
Summary:
Screen resolution for HDTV has become comparable with a clock speed of the microprocessor for personal computers. While the clock speed is not necessarily a perfect indicator of overall system performance, the consumer often thinks of Sun
Interestingly, when a group of experts, the SMPTE (Society of Motion Picture and Television Engineers),recently the importance of the resolution, came in fourth. The report ranks SMPTE contrast, color saturation, color temperature and grayscale before the dissolution of meaning. The Imaging Science Foundation has reached a similar conclusion. However, most manufacturers of HDTVs combine the characteristics of quality, such as improved contrast ratio screen resolutions than the top of the line high-definition TV. So if you buy a set with the top of the screen resolution, more than likelyget the tip of the manufacturer, its product line images for other important criteria screen.
Prices have fallen significantly over the past two years, but it seems that the rate of price reduction has significantly slowed recently. "TV Buyers who attend large-scale distribution may be more interested in getting a low price and can not consult an expert. However, the TV customers should be aware that prices are lower than at mass retailers, mainly due to the fact thatthese stores tend to carry second phase of brand TVs, rather than big brands like Sony or Panasonic. When the prices of a particular model of TV than any type of seller, the prices are surprisingly similar, "JD Power and Larry Wu.
And a final note, you should look for the audio side of the system account. George Lucas (Star Wars) once said audio is half the viewing experience. It 'also true for a good football or basketball game.
HDTV - 720p, 1080i and 1080p?Western Digital WD TV Live Plus 1080p HD Media Player by Western Digital HDTV Reviews | High Definition Television Reviews And All LEDTV 3DTV
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