accumimage and accumcolor are packages for the Go programming language that provide the ability to accumulate and average colors. accumcolor.NRGBA is the accumulating analogue of the Go standard library's color.NRGBA (a single pixel of non-alpha-premultiplied red, green, blue, and alpha channels), and accumimage.NRGBA is the accumulating analogue of the Go standard library's image.NRGBA (a 2-D array of NRGBA pixels). Another type, accumcolor.LabA, accumulates color in the CIE L*a*b* + alpha color space, in which colors blend in a more perceptually uniform manner. accumimage.LabA provides a 2-D array of accumcolor.LabA pixels.
In addition to three color channels and an alpha channel, accumcolor.NRGBA and accumcolor.LabA contain a tally of the number of colors that have been added together. The Add method adds another color to the existing one, each weighted by their tally. The NRGBA method divides each channel in an accumcolor.NRGBA by the tally to produce an ordinary color.NRGBA; the Colorful method divides each channel in an accumcolor.LabA by the tally to produce a colorful.Color from the go-colorful package.
accumimage and accumcolor can be useful for blending multiple overlapping images, for mapping a large number of pixels to a smaller number (e.g., when scaling an image), and for distinguishing pixels in an image that are truly empty (e.g., unvisited in an algorithm that visits all pixels) from pixels that have a color, even one that is fully transparent.
Install accumimage and accumcolor with
go get github.com/spakin/accumimage/v2then simply import accumimage and/or accumimage/accumcolor into your Go program:
import (
"github.com/spakin/accumimage/v2"
"github.com/spakin/accumimage/v2/accumcolor"
)See the pkg.go.dev documentation for accumimage and accumcolor.