2019-02-10, 14:55
Dithering Explained
Dithering 8-bits to 6-bits
Dithering is a method of approximating a color from a mixture of other colors when the required color value is not available for the desired bit depth. When converting one data set to another non-matching data set (e.g., larger bit depth converted to a smaller bit depth), quantization (rounding) errors are generated because the digital conversion cannot match the original source value to a unique destination value.
Rather than round all decimals to the same value, creating a simple gradient consisting completely of "96 gray," for instance, dithering spreads out the rounding errors from each calculated RGB value to neighboring pixels. This creates a random yet controlled pattern of mixed colors that better approximates the varied color shades present in the original gradient. What would be harsh edges caused by rounded color values (known as color banding) are replaced by gradients with smooth transitions between color shades. Such a randomized use of colors is a way to create an artificial sense of having an expanded color palette. This dithering pattern adds a little noise to the image. The larger the output bit depth, the lower the visible dithering noise.
Dithering Math Explained
Dithering 8-bits to 6-bits
Dithering is a method of approximating a color from a mixture of other colors when the required color value is not available for the desired bit depth. When converting one data set to another non-matching data set (e.g., larger bit depth converted to a smaller bit depth), quantization (rounding) errors are generated because the digital conversion cannot match the original source value to a unique destination value.
Rather than round all decimals to the same value, creating a simple gradient consisting completely of "96 gray," for instance, dithering spreads out the rounding errors from each calculated RGB value to neighboring pixels. This creates a random yet controlled pattern of mixed colors that better approximates the varied color shades present in the original gradient. What would be harsh edges caused by rounded color values (known as color banding) are replaced by gradients with smooth transitions between color shades. Such a randomized use of colors is a way to create an artificial sense of having an expanded color palette. This dithering pattern adds a little noise to the image. The larger the output bit depth, the lower the visible dithering noise.
Dithering Math Explained