Datasheet

e-Paper ESP8266 Driver Board User Manual
DITHERING
In case of smooth colored pictures during the Level processing an image looses a lot of thin
details expressed by smooth gradient of colors situated close to each other in the color diagram.
The most of gradients cover large areas of pictures taken by camera, thus it is possible to
express some shades by mixing closest available colors on those areas.
Eyes feel the average color of pixels in a small area. It means there are more seeming
colors, but in other hand the picture seems noisy we well or as if it has low resolution. Good
algorithms of color the mixing can prevent pixilation (creating clearly seen small grain-like areas
in a picture). One of them is the Dithering.
The application uses the Floyd-Steinberg Dithering - most famous 2D error diffusion
formula (was published by Robert Floyd and Louis Steinberg in 1976). It diffuses errors according
the pattern shown in figure 8.
Here X - is an error (scalar/vector difference between original and available
grayscale/colored value of pixel). This error is distributed between right, right-bottom, bottom
and left-bottom pixels, is just added to their values with factors 7/16, 1/16, 5/16 and 3/16
respectively. Thus the average original color stays within this small group of pixels. The algorithm
doesn’t change left, left-top, top and right-top pixels because they are already corrected at