3 ms·
It is possible to see banding at 8bit with a final product. Imagine a flat gradient across the screen from black to white. 255 levels over say 2000 pixels (clos
by icegreentea 13y ago
It is possible to see banding at 8bit with a final product. Imagine a flat gradient across the screen from black to white. 255 levels over say 2000 pixels (close enough) on a screen like... 6 feet across. Unless the gradient is dithered (either in the TV, or at the source...), you get ~8 pixel wide bands, which works out to 1/4th inch bands, which is definitely visible in certain situations.
Dithering is certainly a solution, but higher bit depths also works, and in a way that's much cleaner.
EDIT: This implies of course that the final display is also capable of high bit-depth display. Obviously, if the display is limited to 8bit, then it's kinda useless. I think the author's point was that HDMI 2.0 -should- be kinda future proof, and -should- anticipate widespread adoption of high bit-depth displays.
- Zardoz84 13y ago> It is possible to see banding at 8bit with a final product. Imagine a flat gradient across the screen from black to white. 255 levels over say 2000 pixels (close enough) on a screen like... 6 feet across. Unless the gradient is dithered (either in the TV, or at the source...), you get ~8 pixel wide bands, which works out to 1/4th inch bands, which is definitely visible in certain situations. If you have a RGB image were each color component uses a byte to represent it, you should have a effective Luma bit depth of 8 bit. Well, this is false for LCD screens because they have a effective Luma bit depth of 7 or 6 bits (or worst), so even using a VGA signal (analog signal) you get banding on these screens, were on a old good CRT screen you never appreciate it.
- lutorm 13y agoYeah, the eye is extremely good at picking up sharp edges, so these gradients might look perfectly flat if there weren't discontinuities in them.