smart_canteen/app/utils/qrcode/decodeFile.go

package qrcode

import (
	"image"
	_ "image/jpeg"
	_ "image/png"
	"os"

	"github.com/makiuchi-d/gozxing"
	"github.com/makiuchi-d/gozxing/qrcode"
)

func DecodeFile(fi string) (string, error) {
	file, err := os.Open(fi)
	if err != nil {
		return "", err
	}
	img, _, err := image.Decode(file)
	if err != nil {
		return "", err
	}
	// prepare BinaryBitmap
	bmp, err := gozxing.NewBinaryBitmapFromImage(img)
	if err != nil {
		return "", err
	}
	// decode image
	result, err := qrcode.NewQRCodeReader().Decode(bmp, nil)
	if err != nil {
		return "", err
	}
	return result.String(), nil
}