diff --git a/cmd/zplgfa/main.go b/cmd/zplgfa/main.go
index 905422c..289a3d2 100644
--- a/cmd/zplgfa/main.go
+++ b/cmd/zplgfa/main.go
@@ -3,10 +3,6 @@ package main
 import (
 	"flag"
 	"fmt"
-	"github.com/anthonynsimon/bild/blur"
-	"github.com/anthonynsimon/bild/effect"
-	"github.com/anthonynsimon/bild/segment"
-	"github.com/nfnt/resize"
 	"image"
 	"image/color"
 	_ "image/gif"
@@ -15,8 +11,14 @@ import (
 	"log"
 	"math"
 	"os"
-	"simonwaldherr.de/go/zplgfa"
 	"strings"
+
+	"github.com/anthonynsimon/bild/blur"
+	"github.com/anthonynsimon/bild/effect"
+	"github.com/anthonynsimon/bild/segment"
+	"github.com/nfnt/resize"
+
+	"simonwaldherr.de/go/zplgfa"
 )
 
 func main() {
@@ -72,19 +74,16 @@ func main() {
 	}
 
 	// apply image manipulation functions
-	if strings.Contains(imageEditFlag, "monochrome") {
+	switch {
+	case strings.Contains(imageEditFlag, "monochrome"):
 		img = editImageMonochrome(img)
-	}
-	if strings.Contains(imageEditFlag, "blur") {
+	case strings.Contains(imageEditFlag, "blur"):
 		img = blur.Gaussian(img, float64(config.Width)/300)
-	}
-	if strings.Contains(imageEditFlag, "edge") {
+	case strings.Contains(imageEditFlag, "edge"):
 		img = effect.Sobel(img)
-	}
-	if strings.Contains(imageEditFlag, "segment") {
+	case strings.Contains(imageEditFlag, "segment"):
 		img = segment.Threshold(img, 128)
-	}
-	if strings.Contains(imageEditFlag, "invert") {
+	case strings.Contains(imageEditFlag, "invert"):
 		img = editImageInvert(img)
 	}
 
diff --git a/example_test.go b/example_test.go
index a925e6c..b5044c4 100644
--- a/example_test.go
+++ b/example_test.go
@@ -1,8 +1,14 @@
 package zplgfa_test
 
 import (
+	"bytes"
+	"encoding/base64"
 	"fmt"
+	"image"
+	_ "image/png"
+	"log"
 	"simonwaldherr.de/go/zplgfa"
+	"strings"
 )
 
 func ExampleCompressASCII() {
@@ -11,3 +17,40 @@ func ExampleCompressASCII() {
 
 	// Output: NFL0
 }
+
+func ExampleConvertToZPL() {
+	// base64 encoded image file (./tests/test6.png)
+	str := `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`
+
+	// decode base64 encoded image
+	data, err := base64.StdEncoding.DecodeString(str)
+	if err != nil {
+		fmt.Println("error:", err)
+		return
+	}
+
+	// load image head information from bytes reader
+	config, format, err := image.DecodeConfig(bytes.NewReader(data))
+	if err != nil {
+		log.Printf("Warning: image not compatible, format: %s, config: %v, error: %s\n", format, config, err)
+		return
+	}
+
+	// load and decode image from bytes reader
+	img, _, err := image.Decode(bytes.NewReader(data))
+	if err != nil {
+		log.Printf("Warning: could not decode the file, %s\n", err)
+		return
+	}
+
+	// convert image to zpl string
+	zplstr := zplgfa.ConvertToZPL(img, zplgfa.CompressedASCII)
+
+	// remove whitespace - only for the test
+	zplstr = strings.Replace(zplstr, " ", "", -1)
+	zplstr = strings.Replace(zplstr, "\n", "", -1)
+
+	fmt.Println(zplstr)
+
+	// Output: ^XA,^FS^FO0,0^GFA,52,51,3,FFFF00::FE3F00::FFFF00FFE300::FFFF00E22300::FFFF00::^FS,^XZ
+}