Most people are aware of High Definition (HD) even if they still have a Standard Definition (SD) television. But now there is another alternative that is called Near High Definition.
A Near High Definition is new type of television that manufactures have launched to enhance a SD picture so that it is Near to High Definition.
We already have High Definition so why do we need Near High Definition TVs ?
High definition broadcasts arent available on normal terrestrial analogue or digital broadcasts such as Freeview. The only broadcaster that provides limited HD content free of charge at present is the BBCs and ITVs Freesat broadcasts. Sky has the most HD channels but you have to pay a monthly subscription charge. The chances are that you will still watch standard definition broadcasts because not all programmes are available in HD. Alternative sources of HD are Blu-ray discs, download from the web or On-Demand services from Virgin Medias Cable serve or Tisclai. Because the options for watching HD are restricted producers believe that upscaling televisions with Near High Definition pictures will allow people to take advantage of the potential of HD television sets using a SD source.
What is a Standard Definition picture.
The picture on an LCD or Plasma television is made of many thousands of pixels. In the UK the television system is known as Pal which is broadcast with 576 hozontal lines of 768 pixels (576x768 pixels).
When a television picture is broadcast the moving picture is broken down in to frames. These frames are actually split in to two half fields A and B, where the A field consists of the odd lines and the B frame consists of the even lines. This type of picture is known as an interlaced image. When the two fields of each frame are combined or interlaced they create a complete frame as each field is alternately scanned or painted onto the television screen. Where the odd and even fields are displayed alternately each showing 25 times a second or 50 times a second when displayed alternately together, hence the term a 50hz picture.
The number of pixels that make up a picture is known as the resolution. So a television with more pixels will have a higher resolution. Generally the higher the resolution is on a television the sharper the image that it can produce. Televisions with a high resolution are known as High Definition televisions.
All UK high definition broadcasts are either at 720 p (1280pixels x 720pixels) or 1080i (1920pixels x 1080pixels). You will need a television of a specification of at least HD Ready which will be able to display a 720P broadcast. There arent any broadcasts of 1080 P ( 1920pixels x 1080pixels ) material in the UK at this moment in time. To take advantage of the full reolution of a 1080P tv set you will have to view either Blu-Ray discs or downloads from the internet.
A Full HD Ready 1080p television has a picture resolution that is about 5 times the resolution of a Standard Definition television. This is why with suitable source material a Full HD television has such a stunning picture.
On TVs that have Near HD they use an upscaler to transform an SD picture into 1080P.
An Upscaler transforms an input signals resolution to the resolution of the TVs screen. Therefore if you have an HD Ready TV (1280x720 pixels) or a Full HD 1080P TV (1920x1080 pixels) and you watch Freeview or a DVD that has a resolution of 768x576 pixels the TV has to upscale the picture to fill the different resolution TV screen. If television didnt have a digital upscaler the image wouldnt fill the screen and there would be areas of the screen that would be black and unused due the resolution mismatch of the HD TVs native resolution and the resolution of the source.
HD televisions have a video processing chip that upscales the image so that the incoming picture signal has the same resolution as the native resolution of the screen. This is done by first interlacing the picture which allows the digital algorithms and filters to interpolate the image by adding extra pixels and lines.
The ability of a TV to upscale an image is dependant on how good the source input and the quality of upscaler chip. The quality of upscaling chips varies from TV to TV as does the quality of other internal components and the actual screen which affect the quality of the picture displayed.
An upscaler is required by all LCD and Plasma TVs so that they are compatible with the various source resolutions that they may be presented with so that they fill the native resolution of the screen. It may seem that the Near HD TVs arent doing anything different to any other LCD or Plasma TV but it is how they do it that is different. The Near HD TVs use a more powerful upscaling processor chip which means that they are much better at upscaling than ordinary TVs.
No matter how sophisticated the algorithms are that guesstimate how the additional pixels should look an upscaled SD image isnt as good as an actual true 1080P HD picture.
Toshiba have a range of TVs that use the cell processor from the Sony PS3 to upscale the image to the Near HD 1080P resolution. Toshiba have called this feature Resolution + which is featured in their ZV series of TVs. This feature vastly improves the picture quality of a SD picture source.
The enhanced picture is achieved by the cell processor comparing adjacent image frames which it then combines the pixel detail of to enhance the definition. The picture quality is clearer with sharper and richer pictures. The detail is enhanced which sharpens the edge of images and reduces 3D noise. The colour palette is more natural due to enhancement of the blue and green shades minimizing the loss of clarity that upscaling can often cause. Contrast Enhancement results in dark areas becoming darker whilst at the same time the bright areas maintain their brightness. This results in Standard Definition images being crisp and rich with sharper edges and improved texture but the flat areas are not changed.
DVD Players with Near HD
A DVD players with near HD picture processing isnt the same as one with progressive scan which converts interlaced images into full frames by combining the two fields that make up the frame so that they are both displayed at the same time. This results in more fluid motion, improved vertical resolution and no interlace artifacts such as flickering between lines. Progressive scan uses the existing two A and B fields pixels from each frame to create a full frame but it doesnt generate additional lines or pixels like an upscaler does.
There is a number of upscaling DVD players presently available on the market. These machines dont deinterlace the image before upscaling it from SD. Only Toshiba currently has an upscaling Near HD DVD Player, the XDE model, that upscales the SD 576 line picture to 1080P lines Near HD. This is done in a similar way to the Resolution + TVs from Toshiba where the picture is enhanced so that it is more detailed with lifelike colours and better contrast levels.
Should you buy Near HD TVs and DVD Players?
Obviously an upscaled SD 576 line picture is not as good as a 1080P Full HD picture no matter how much digital processing is done. Nonetheless there is no doubt that a much better upscaler in a television produces a noticeable improvement in the picture quality so that it is closer to 1080P picture. A Near HD TV makes even more sense if you arent willing to pay a monthly charge for HD from Sky, Virgin Medias Cable, Tiscalis Service or Blu-Ray discs. Even if you opt for Freesat there is a limited amount of HD channels available so your choice of programmes is limited. Because HD isnt freely available, especially with out paying for it, a Near HD TV is worth considering that will produce an improved picture with virtually any content including 480i, 576i, 720p as well as DVD, Standard Definition Broadcasts and computer games. With all of these sources the picture will be upscaled to 1080P.
The Near HD TVs offer the ultimate flexibility with the ability to enhance almost any source. As more HD options become available either chargeable or free the TV is capable of receiving and displaying 1080P sources so you wont need to upgrade your TV. Toshiba is the only company that offers Near HD TVs and a DVD Player but others will follow soon.
A Near High Definition is new type of television that manufactures have launched to enhance a SD picture so that it is Near to High Definition.
We already have High Definition so why do we need Near High Definition TVs ?
High definition broadcasts arent available on normal terrestrial analogue or digital broadcasts such as Freeview. The only broadcaster that provides limited HD content free of charge at present is the BBCs and ITVs Freesat broadcasts. Sky has the most HD channels but you have to pay a monthly subscription charge. The chances are that you will still watch standard definition broadcasts because not all programmes are available in HD. Alternative sources of HD are Blu-ray discs, download from the web or On-Demand services from Virgin Medias Cable serve or Tisclai. Because the options for watching HD are restricted producers believe that upscaling televisions with Near High Definition pictures will allow people to take advantage of the potential of HD television sets using a SD source.
What is a Standard Definition picture.
The picture on an LCD or Plasma television is made of many thousands of pixels. In the UK the television system is known as Pal which is broadcast with 576 hozontal lines of 768 pixels (576x768 pixels).
When a television picture is broadcast the moving picture is broken down in to frames. These frames are actually split in to two half fields A and B, where the A field consists of the odd lines and the B frame consists of the even lines. This type of picture is known as an interlaced image. When the two fields of each frame are combined or interlaced they create a complete frame as each field is alternately scanned or painted onto the television screen. Where the odd and even fields are displayed alternately each showing 25 times a second or 50 times a second when displayed alternately together, hence the term a 50hz picture.
The number of pixels that make up a picture is known as the resolution. So a television with more pixels will have a higher resolution. Generally the higher the resolution is on a television the sharper the image that it can produce. Televisions with a high resolution are known as High Definition televisions.
All UK high definition broadcasts are either at 720 p (1280pixels x 720pixels) or 1080i (1920pixels x 1080pixels). You will need a television of a specification of at least HD Ready which will be able to display a 720P broadcast. There arent any broadcasts of 1080 P ( 1920pixels x 1080pixels ) material in the UK at this moment in time. To take advantage of the full reolution of a 1080P tv set you will have to view either Blu-Ray discs or downloads from the internet.
A Full HD Ready 1080p television has a picture resolution that is about 5 times the resolution of a Standard Definition television. This is why with suitable source material a Full HD television has such a stunning picture.
On TVs that have Near HD they use an upscaler to transform an SD picture into 1080P.
An Upscaler transforms an input signals resolution to the resolution of the TVs screen. Therefore if you have an HD Ready TV (1280x720 pixels) or a Full HD 1080P TV (1920x1080 pixels) and you watch Freeview or a DVD that has a resolution of 768x576 pixels the TV has to upscale the picture to fill the different resolution TV screen. If television didnt have a digital upscaler the image wouldnt fill the screen and there would be areas of the screen that would be black and unused due the resolution mismatch of the HD TVs native resolution and the resolution of the source.
HD televisions have a video processing chip that upscales the image so that the incoming picture signal has the same resolution as the native resolution of the screen. This is done by first interlacing the picture which allows the digital algorithms and filters to interpolate the image by adding extra pixels and lines.
The ability of a TV to upscale an image is dependant on how good the source input and the quality of upscaler chip. The quality of upscaling chips varies from TV to TV as does the quality of other internal components and the actual screen which affect the quality of the picture displayed.
An upscaler is required by all LCD and Plasma TVs so that they are compatible with the various source resolutions that they may be presented with so that they fill the native resolution of the screen. It may seem that the Near HD TVs arent doing anything different to any other LCD or Plasma TV but it is how they do it that is different. The Near HD TVs use a more powerful upscaling processor chip which means that they are much better at upscaling than ordinary TVs.
No matter how sophisticated the algorithms are that guesstimate how the additional pixels should look an upscaled SD image isnt as good as an actual true 1080P HD picture.
Toshiba have a range of TVs that use the cell processor from the Sony PS3 to upscale the image to the Near HD 1080P resolution. Toshiba have called this feature Resolution + which is featured in their ZV series of TVs. This feature vastly improves the picture quality of a SD picture source.
The enhanced picture is achieved by the cell processor comparing adjacent image frames which it then combines the pixel detail of to enhance the definition. The picture quality is clearer with sharper and richer pictures. The detail is enhanced which sharpens the edge of images and reduces 3D noise. The colour palette is more natural due to enhancement of the blue and green shades minimizing the loss of clarity that upscaling can often cause. Contrast Enhancement results in dark areas becoming darker whilst at the same time the bright areas maintain their brightness. This results in Standard Definition images being crisp and rich with sharper edges and improved texture but the flat areas are not changed.
DVD Players with Near HD
A DVD players with near HD picture processing isnt the same as one with progressive scan which converts interlaced images into full frames by combining the two fields that make up the frame so that they are both displayed at the same time. This results in more fluid motion, improved vertical resolution and no interlace artifacts such as flickering between lines. Progressive scan uses the existing two A and B fields pixels from each frame to create a full frame but it doesnt generate additional lines or pixels like an upscaler does.
There is a number of upscaling DVD players presently available on the market. These machines dont deinterlace the image before upscaling it from SD. Only Toshiba currently has an upscaling Near HD DVD Player, the XDE model, that upscales the SD 576 line picture to 1080P lines Near HD. This is done in a similar way to the Resolution + TVs from Toshiba where the picture is enhanced so that it is more detailed with lifelike colours and better contrast levels.
Should you buy Near HD TVs and DVD Players?
Obviously an upscaled SD 576 line picture is not as good as a 1080P Full HD picture no matter how much digital processing is done. Nonetheless there is no doubt that a much better upscaler in a television produces a noticeable improvement in the picture quality so that it is closer to 1080P picture. A Near HD TV makes even more sense if you arent willing to pay a monthly charge for HD from Sky, Virgin Medias Cable, Tiscalis Service or Blu-Ray discs. Even if you opt for Freesat there is a limited amount of HD channels available so your choice of programmes is limited. Because HD isnt freely available, especially with out paying for it, a Near HD TV is worth considering that will produce an improved picture with virtually any content including 480i, 576i, 720p as well as DVD, Standard Definition Broadcasts and computer games. With all of these sources the picture will be upscaled to 1080P.
The Near HD TVs offer the ultimate flexibility with the ability to enhance almost any source. As more HD options become available either chargeable or free the TV is capable of receiving and displaying 1080P sources so you wont need to upgrade your TV. Toshiba is the only company that offers Near HD TVs and a DVD Player but others will follow soon.
About the Author:
Armadeus Cornelius is an AV enthusiast and expert with nearly 20 years experience in consumer electronics. His website at www.digitaldirect.co.uk offers 'Near HD' TVsand a large selection of AV products at low prices. For your convenience you may also find these links useful dvd player upconvert and toshiba hd
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