Wirenboard 5の電子インクまたはGoでバーコードを描く

 package main import ( "bytes" "fmt" "image" "log" "os" "image/color" "image/draw" "golang.org/x/image/bmp" "syscall" "github.com/boombuler/barcode" "github.com/boombuler/barcode/ean" "github.com/boombuler/barcode/qr" ) func main() { switch string(os.Args[2]) { case "qr": base64 := os.Args[3] log.Println("Original data:", base64) code1pixel, err := qr.Encode(base64, qr.L, qr.Unicode) if err != nil { log.Fatal(err) } log.Println("Encoded data: ", code1pixel.Content()) if base64 != code1pixel.Content() { log.Fatal("data differs") } log.Println("Encoded data: ", code1pixel.Content()) if base64 != code1pixel.Content() { log.Fatal("data differs") } codeScalled, err := barcode.Scale(code1pixel, 300, 200) if err != nil { log.Fatal(err) } drtest(codeScalled) case "ean": // code, err := ean.Encode("123456789012") code1pixel, err := ean.Encode(os.Args[3]) if err != nil { log.Fatal(err) } log.Println("Encoded data: ", code1pixel.Content()) codeScalled, err := barcode.Scale(code1pixel, 300, 300) if err != nil { log.Fatal(err) } drtest(codeScalled) } } func drtest(imgSrc image.Image) { // create a new Image with the same dimension of image newImg := image.NewGray(image.Rect(0, 0, 600, 800)) // we will use white background to replace background // you can change it to whichever color you want with // a new color.RGBA{} and use image.NewUniform(color.RGBA{<fill in color>}) function draw.Draw(newImg, newImg.Bounds(), &image.Uniform{color.White}, image.Point{}, draw.Src) // paste image OVER to newImage draw.Draw(newImg, newImg.Bounds().Add(image.Point{150, 300}), imgSrc, imgSrc.Bounds().Min, draw.Over) buf := new(bytes.Buffer) err := bmp.Encode(buf, newImg) if err != nil { fmt.Println(err) os.Exit(1) } send_s3 := buf.Bytes() fmt.Println("OK") if os.Args[1] != "false" { devout(send_s3[1078:]) } } func devout(buffer []byte) { // disk := "/dev/sde" disk := os.Args[1] var fd, numread int var err error fd, err = syscall.Open(disk, syscall.O_RDWR, 0777) if err != nil { fmt.Print(err.Error(), "\n") return } //WRITE numread, err = syscall.Write(fd, buffer) if err != nil { fmt.Print(err.Error(), "\n") } fmt.Printf("Numbytes write: %d\n", numread) // fmt.Printf("Buffer: %x\n", buffer[:1000]) err = syscall.Close(fd) if err != nil { fmt.Print(err.Error(), "\n") } }