Using the Color package to create new Color from RGB value?

[stapia.g...@gmail.com]

http://stackoverflow.com/questions/22083460/using-the-color-package-to-create-new-color-from-rgb-value

I'm trying to create a new `Color` object using RGB values I have in variables:

http://golang.org/pkg/image/color/

---

    package main

    

    import (

    "fmt"

    "image"

    _ "image/gif"

    _ "image/jpeg"

    _ "image/png"

    "os"

    )

    

    func main() {

    reader, err := os.Open("test-image.jpg")

    if err != nil {

    fmt.Fprintf(os.Stderr, "%v\n", err)

    }

    

    image, _, err := image.Decode(reader)

    if err != nil {

    fmt.Fprintf(os.Stderr, "%s", err)

    }

    

    bounds := image.Bounds()

    

    for i := 0; i <= bounds.Max.X; i++ {

    for j := 0; j <= bounds.Max.Y; j++ {

    pixel := image.At(i, j)

    if i == 0 && j == 0 {

    red, green, blue, _ := pixel.RGBA()

    averaged := (red + green + blue) / 3

                   

                                // This FromRGBA function DOES NOT EXIST!

    grayColor := Color.FromRGBA(averaged, averaged, averaged, 1)

    

    // Then I could do something like:

    grayColor.RGBA() // This would work since it's a type Color.

    

    }

    }

    }

    }

I can't seem to find any package Function that generates a new Color object given rgba values. 

Any recommendations?

[Stephen Gutekanst]

grayColor := color.RGBA{averaged, averaged, averaged, 1}

type RGBA struct {
        R, G, B, A uint8
}

[Matt Harden]

If you want the grayColor to be a variable of type Color, then

grayColor := color.RGBA{averaged, averaged, averaged, 1}.(color.Color)

If you want the gray to be a better visual approximation of the given color, don't use the average of the RGB components. Use GrayModel (or GrayModel16):

grayColor := color.GrayModel.Convert(pixel)

--
You received this message because you are subscribed to the Google Groups "golang-nuts" group.
To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts...@googlegroups.com.
For more options, visit https://groups.google.com/groups/opt_out.