what is 36 bit and deep color ?

[hammer]

I would like to know what they mean by a tv and blue ray player that can display 36 bit and deep color. Do they work with each other ? I was told that blue ray disc are not even made at 36 bit, is it something the human eye can actually see or is this a case of marketing hype ?

[MrBoylan]

Originally Posted by hammer

I would like to know what they mean by a tv and blue ray player that can display 36 bit and deep color. Do they work with each other ? I was told that blue ray disc are not even made at 36 bit, is it something the human eye can actually see or is this a case of marketing hype ?

First a small comment about units - "36-bit color support" translates to 12-bit color. Huh? Yes, it's true. They're the same thing. 12-bit color encoding times three channels (red, green and blue) means you have "36-bit color support." So really it's just two different ways of referring to the same measurement. For our purposes, let's refer to "36-bit color support" as 12-bit color, for comparison purposes (and because this is the standard way of referring to color encoding).

DeepColor support (available in HDMI 1.3 and above) allows the HDMI spec to support 10-bit, 12-bit and 16-bit color precision. And while it's true that Blu-ray Discs only support 8-bit color encoding (using 4:2:0 chroma subsampling), this doesn't mean that enhanced color precision available in DeepColor is complete marketing hype. Some Blu-ray players with DeepColor support can "upsample" the 8-bit color palate to 10, 12 or 16 bits in order to interpolate intermediate colors between the color values encoded on the disc. This can help to produce smoother color transitions (with no "banding") when such upconverted material is displayed on a DeepColor-compatible display device.

Another way that players and displays can support enhanced color precision is by compensating for color encoding errors that happen as a result of Blu-ray's chroma subsampling scheme. The Blu-ray format itself uses "4:2:0 chroma subsampling." This means that while Black and White data (aka brightness or luma) is stored for each and every one of the 1920x1080 pixels, the color data is only stored for half the pixels vertically and horizontally. So for every block of 4 pixels on the screen, luma data is stored for all 4 pixels while color data is stored once for that 4-pixel block. Because the human eye is much more sensitive to brightness and line detail than to color detail, the additional color data that is discarded is not generally noticeable at normal viewing distances.

But a "clever" Blu-ray player (like the Panasonic BD60/BD80, for example with its Uniphier processor as well as some Pioneer players) can analyze the 4:2:0-encoded signal and then interpolate the missing color data, outputting a 4:4:4 output, with color detail accompanying every single pixel. The primary benefit of this is better gradations of color across thes screen and cleaner edges along colored borders. Typically this kind of thing is only visible in large screen sizes (50 inches and up). But in order to see the benefits of this 4:4:4 color processing, the display must also support a 4:4:4 input. Not all displays support this.

And although having "DeepColor" support with 36-bit color (aka 12-bit color) does not always mean that a display will also support a 4:4:4 color input, you do frequently see both specs on higher end displays. In the 2009 Panasonic display line, for example, only the V10 and Z1 series support 4:4:4 color inputs, while others in the line also support DeepColor.

To make matters even more confusing, there is another color spec called "x.v.color" or xvYCC which you'll also find listed as a spec on many players and displays. This is not the same thing as DeepColor. While DeepColor allows you to map gradations of color with more precision, xvYCC allows you to map colors in a greater range - e.g., "redder reds" or "deeper indigos." xvYCC color is something that you can find on some HD camcorders. Using xvYCC color, these camcorders can actually extend the range of colors available about 1.8x over standard RGB color ranges.

Like DeepColor, xvYCC is not available on Blu-ray but it is something you can do yourself for your own home movies, with the proper camcorder, a DVD or Blu-ray burner, and with a Blu-ray player and display device that support xvYCC color.

So, bottom line is that DeepColor with support for color samples over 8 bits and xvYCC color are things that you will not find on Blu-ray Discs, but are useful features to have anyway, on both the player and the display if you're interested in getting the highest quality image.

Hope that helps.

-Chris

[Daylightdon]

WOW!!!
Phew!!!!
I am so GLAD I bought the BD-80 and the V10 50 inch!!!!