qrcode

go-qrcode

QR code (abbreviated from Quick Response Code) is the trademark for a type of matrix barcode (or two-dimensional barcode) first designed in 1994 for the automotive industry in Japan. A barcode is a machine-readable optical label that contains information about the item to which it is attached. A QR code uses four standardized encoding modes (numeric, alphanumeric, byte/binary, and kanji) to store data efficiently; extensions may also be used

Features

• Normally generate QR code across version 1 to version 40.

• Automatically analyze QR version by source text.

• Specifying cell shape allowably with WithCustomShape, WithCircleShape (default is rectangle)

• Specifying output file's format with WithBuiltinImageEncoder, WithCustomImageEncoder (default is JPEG)

• Not only shape of cell, but also color of QR Code background and foreground color.

• WithLogoImage, WithLogoImageFilePNG, WithLogoImageFileJPEG help you add an icon at the central of QR Code.

• WithBorderWidth allows to specify any width of 4 sides around the qrcode.

Install

go get -u github.com/yeqown/go-qrcode

Usage

link to CODE

package main

import (
	"fmt"

	qrcode "github.com/yeqown/go-qrcode"
)

func main() {
	qrc, err := qrcode.New("https://github.com/yeqown/go-qrcode")
	if err != nil {
		fmt.Printf("could not generate QRCode: %v", err)
	}

	// save file
	if err := qrc.Save("../testdata/repo-qrcode.jpeg"); err != nil {
		fmt.Printf("could not save image: %v", err)
	}
}

Options

now go-qrcode provides some options to customize output QRCode.

// WithBgColor background color
func WithBgColor(c color.Color) ImageOption {}

// WithBgColorRGBHex background color
func WithBgColorRGBHex(hex string) ImageOption {}

// WithFgColor QR color
func WithFgColor(c color.Color) ImageOption {}

// WithFgColorRGBHex Hex string to set QR Color
func WithFgColorRGBHex(hex string) ImageOption {}

// WithLogoImage .
func WithLogoImage(img image.Image) ImageOption {}

// WithLogoImageFilePNG load image from file, PNG is required
func WithLogoImageFilePNG(f string) ImageOption {}

// WithLogoImageFileJPEG load image from file, JPEG is required
func WithLogoImageFileJPEG(f string) ImageOption {}

// WithQRWidth specify width of each qr block
func WithQRWidth(width uint8) ImageOption {}

// WithCircleShape use circle shape as rectangle(default)
func WithCircleShape() ImageOption {}

// WithCustomShape use custom shape as rectangle(default)
func WithCustomShape(shape IShape) ImageOption {}

// WithBuiltinImageEncoder option includes: JPEG_FORMAT as default, PNG_FORMAT.
// This works like WithBuiltinImageEncoder, the different between them is
// formatTyp is enumerated in (JPEG_FORMAT, PNG_FORMAT)
func WithBuiltinImageEncoder(format formatTyp) ImageOption

// WithCustomImageEncoder to use custom image encoder to encode image.Image into
// io.Writer
func WithCustomImageEncoder(encoder ImageEncoder) ImageOption

// WithBorderWidth specify the both 4 sides' border width. Notice that
// WithBorderWidth(a) means all border width use this variable `a`,
// WithBorderWidth(a, b) mean top/bottom equal to `a`, left/right equal to `b`.
// WithBorderWidth(a, b, c, d) mean top, right, bottom, left.
func WithBorderWidth(widths ...int) ImageOption

use options in New and NewWithConfig.

NOTICE: NewWithSpecV is deprecated

import (
	qrcode "github.com/yeqown/go-qrcode"
)

// generating QR Code with source text and output image options.
qrc, _ := qrcode.New("text", WithQRWidth(x)) // x is uint8 (0 - 255)

// OR generating QR Code with specified ErrorCorrection Level and Encode Mode,
// output image options are also available.
qrc, _ := qrcode.NewWithConfig("text", config, WithQRWidth(x))

qrc.Save("path/to/qrcode.png")

following are some shots:

Documention

Jump to go.dev/github/yeqown/go-qrcode

• How to use WithCustomShape

Links

• QR Code tutori
• QRCode Wiki
• 二维码详解（QR Code）
• 数据编码