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Join Date: May 2008
Location: San Francisco - East Bay area
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Every video display in the world has a "native" color space. It would be impossible to create a video display that does NOT have a "native" color space. You can't have a car without an onboard means of propulsion of some kind... well, you could, but it wouldn't be worth anything. A video display without images wouldn't be worth anything either. Some TVs even have a color space menu selection and sometimes there's a "Native" choice in the list.
But there are BAD native color spaces and GOOD native color spaces. A BAD native color space would have one or more primary or complimentary colors undersaturated... if that happens, you can't fix it with TV controls or video processor controls. Once a color is at 100% saturation with the display's controls, and the color is still undersaturated, there are no controls or processor that can make the saturation 110% or 150% just so the right color is achieved. Likewise, if you have made one of the primary or complementary colors as bright as it can be made with the TV controls and it is still not bright enough, there's no way to correct that in the TVor with an external video processor.
Rec 601 is a document that described standard definition color space.
Rec 709 is a document that describes high definition color space.
You have to use the right color space for the content you are viewing or you end up with errors, probably visible errors.
If the NATIVE color space is larger than the Rec 709 color space, you should be able to make all the primary and complimentary colors (red, green, blue, cyan, magenta, yellow) accurate using the CMS controls in the TV (if they work well). If there are no CMS controls in the TV, you can make the primaries and complementaries accurate with an external video processor. But if the NATIVE color space is smaller (anywhere) than the Rec 709 color space, and the controls in the TV can't correct whatever color (or colors) is placed "inside" the Rec 709 triangle (undersaturated), there is NO way to fix it.
Fixing color problems typically WILL NOT create artifacts because video processing is done in 10-bit color (30 bits total) at least with Samsung displays having 18-bits. The displayed images are only 8-bits, so when you work in 10-bit (or larger) space when processing the images, there's a lot more "room" to do things and when you are done, you convert the 10-bit (or larger) video data back to 8-bits. That said, there are video displays that are MESSED UP internally. Some Toshiba displays I've reviewed, for example, have CMS controls with a range of +/- 10 and if you move any of the controls beyond +/- 3, you get a horrendous amount of posterization and block artifacts in the images... it's really obvious and really bad. A couple of years before that, their TVs' CMS controls had adjustment ranges of +/- 30 and you could not exceed +/- 10 without the same problems. But that's the ONLY time I've run into TV adjustments that cause image quality to tank in any obvious way.
All the SXRD displays I can remember seeing (all XBR series models) had Rec 601 and Rec 709 color space settings by resolution so you could set 480i & 480p to Rec 601 and set 720p, 1080i, and 1080p to Rec 709.
Color space is only the starting point for video performance though... there are many other image quality deciding/determining factors.
"Movies is magic..." Van Dyke Parks
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