Golang : Generate EAN barcode



Tags : golang barcode ean-8 ean-13 paste-image

Short tutorial on how to use https://github.com/boombuler/barcode package to generate EAN(European Article Number, but now known as International Article Number) barcode. Code adapted from previous codabar tutorial.

Here you go :

 package main

 import (
 "fmt"
 "github.com/boombuler/barcode"
 "github.com/boombuler/barcode/ean"
 "github.com/disintegration/imaging"
 "github.com/llgcode/draw2d"
 "image"
 "image/color"
 "image/draw"
 "os"
 )

 func main() {

 // 13 digits
 code := "5901234123457"

 fmt.Println("Generating Datamatrix barcode for : ", code)

 // see https://godoc.org/github.com/boombuler/barcode/ean
 bcode, err := ean.Encode(code)

 // uncomment if checksum missmatch
 //fmt.Println(err)

 if err != nil {
 fmt.Printf("String %s cannot be encoded\n", code)
 os.Exit(1)
 }

 // scale to 100x100
 bcode, err = barcode.Scale(bcode, 100, 100)

 if err != nil {
 fmt.Println("EAN scaling error : ", err)
 os.Exit(1)
 }

 // now we want to append the code at the bottom
 // of the EAN

 // Create an new image with text data
 // From https://github.com/llgcode/draw2d.samples/tree/master/helloworld
 // Set the global folder for searching fonts
 draw2d.SetFontFolder(".")

 // Initialize the graphic context on an RGBA image
 img := image.NewRGBA(image.Rect(0, 0, 250, 50))

 // set background to white
 white := color.RGBA{255, 255, 255, 255}
 draw.Draw(img, img.Bounds(), &image.Uniform{white}, image.ZP, draw.Src)

 gc := draw2d.NewGraphicContext(img)

 gc.FillStroke()

 // Set the font Montereymbi.ttf
 gc.SetFontData(draw2d.FontData{"Monterey", draw2d.FontFamilyMono, draw2d.FontStyleBold | draw2d.FontStyleItalic})
 // Set the fill text color to black
 gc.SetFillColor(image.Black)

 gc.SetFontSize(14)
 gc.FillStringAt(code, 50, 20)

 // create a new blank image with white background
 newImg := imaging.New(300, 200, color.NRGBA{255, 255, 255, 255})

 //paste the codabar to new blank image
 newImg = imaging.Paste(newImg, bcode, image.Pt(100, 30))

 //paste the text to the new blank image
 newImg = imaging.Paste(newImg, img, image.Pt(50, 150))

 err = draw2d.SaveToPngFile("./ean.png", newImg)

 if err != nil {
 fmt.Println(err)
 os.Exit(1)
 }

 // everything ok
 fmt.Println("EAN barcode generated and saved to ean.png")

 }

Sample output :

EAN barcode golang

References :

https://godoc.org/github.com/boombuler/barcode/ean

Affiliate :

Hire Golang Developers


  See also : Golang : How to generate Code 39 barcode?



Tags : golang barcode ean-8 ean-13 paste-image

By Adam Ng

IF you gain some knowledge or the information here solved your programming problem. Please consider donating to the less fortunate or some charities that you like. Apart from donation, planting trees, volunteering or reducing your carbon footprint will be great too.


Advertisement